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Article Information Authors: Jan A. van Wyk1 Estelle Mayhew2 Affiliations: 1Department of Veterinary Tropical Diseases, University of Pretoria, South Africa 2Department for Telematic Education Innovation, University of Pretoria, South Africa Correspondence to: Jan van Wyk Postal address: Private Bag X04, Onderstepoort 0110, South Africa Dates: Received: 19 Nov. 2012 Accepted: 20 Dec. 2012 Published: 13 Mar. 2013 How to cite this article: Van Wyk, J.A. & Mayhew, E., 2013, ‘Morphological identification of parasitic nematode infective larvae of small ruminants and cattle: A practical lab guide’, Onderstepoort Journal of Veterinary Research 80(1), Art. #539, 14 pages. http://dx.doi.org/10.4102/ ojvr.v80i1.539 Copyright Notice: © 2013. The Authors. Licensee: AOSIS OpenJournals. This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Morphological identification of parasitic nematode infective larvae of small ruminants and cattle: A practical lab guide In This Original Research... Open Access • Abstract • Introduction • Materials and methods    • Faecal cultures and harvesting of infective larvae    • Larva preservation    • Larva preparation for identification    • Larva identification       • Length of sheath tail extension       • Proportion of sheath tail extension comprising a filament • Differential larval count    • Identification procedure • Ethical considerations • Results and discussion    • Differentiation of larvae    • Salient features of L3 of the common nematode genera and/or species       • Trichostrongylus spp.       • Ostertagia and Teladorsagia spp.       • Haemonchus spp.       • Cooperia spp.       • The hookworms, Bunostomum spp. and Gaigeria pachyscelis       • Oesophagostomum spp. and Chabertia ovina       • Nematodirus spp.       • Strongyloides papillosus       • Dictyocaulus spp.       • Protostrongylid lungworm larvae       • Free-living nematodes • Conclusion • Acknowledgements    • Competing interests    • Authors’ contributions • References Abstract Top ↑ In 2004, a new concept was introduced for simplifying identification of larvae of the common nematodes of cattle, sheep and goats that comprises estimates of the lengths of the sheath tail extensions of infective third-stage larvae (L3) of each genus and/or species to that of Trichostrongylus spp., instead of having to be dependent only on measurements in micrometre. For example, if the mean length of the sheath tail extension (the extension of the sheath caudad, beyond the caudal tip of the larva) of Trichostrongylus colubriformis and Trichostrongylus axei is assumed to be ‘X’, then that of Haemonchus contortus is 2.0–2.7 ‘X’ – a difference that is not difficult to estimate. An additional new approach suggested now, particularly for L3 of species and/or genera difficult to differentiate (such as Chabertia ovina and Oesophagostomum columbianum), is to estimate the proportion of the larval sheath tail extension comprising a terminal thin, whip-like filament. For the experienced person, it is seldom necessary to measure more than one or two sheath tail extensions of L3 in a mixed culture, because the identity of most of the remaining L3 can thereafter be estimated in relation to those measured, without having to take further measurements. The aim of this article was to present the novel approach in the form of a working guide for routine use in the laboratory. To facilitate identification, figures and a separate organogram for each of small ruminants and cattle have been added to illustrate the distinguishing features of the common L3. Introduction Top ↑ Based on a review by Van Wyk, Cabaret and Michael (2004) and helminthological literature over nine decades, the present article is aimed, through a novel approach and illustrations drawn to scale, at facilitating the morphological identification of infective nematode larvae (L3) of the common nematodes of small ruminants and cattle. Diagnosis of parasitic nematode infections of ruminants, both qualitative and quantitative, is largely still dependent on relatively inaccurate methods such as faecal worm egg counts and accompanying larva identification, without which no indication can be obtained of the identities of most of the common worm genera, excepting for those genera with morphologically distinct ova, for example Strongyloides papillosus, Nematodirus spp. and Trichuris spp. In contrast, ova of Ostertagia, Teladorsagia, Trichostrongylus, Oesophagostomum, Chabertia spp. and, to some extent, Cooperia, Bunostomum and Gaigeria spp. are either difficult or impossible to differentiate without measurements and computations that are, as yet, impractical for routine use. Although some progress has been made with computerised identification (Christie & Jackson 1982), this has not been developed for general use. Large differences in the pathogenicity of the common worm genera make it essential to know which nematode genera are responsible for cases of morbidity of animals. At present, the only practical method available for routine laboratory estimation of the proportions of the worm genera present in the living animal, is to identify the larvae that are found in fresh faeces (mostly lungworm larvae) or those that develop in faecal cultures (gastrointestinal nematodes). However, it is often only the experienced person who can identify the larvae with a high degree of accuracy and few such persons remain for training the inexperienced. For many of the nematode genera, distinguishing features such as the shape of the cranial extremity (the head) of the larva are practically indistinguishable to all but the practised eye. Measuring first-stage larvae (L1) of protostrongylids and the L3 of strongyles, or the length of the sheath tail extension (STE) (from the caudal tip of the larva to the tip of the STE – ‘c’ in Figure 1) can aid identification, but, being too time-consuming, it is not practical to measure each larva during routine differential diagnosis. In this article, a simplified, better-structured method is described for differentiating the L1 of various genera of protostrongylids and the L3 of strongyles from one another. Whilst some conventional characteristics are still used for identification, the novel approach principally comprises a comparison of the lengths of the STEs of L3 of the unknown identity to those of Trichostrongylus axei and Trichostrongylus colubriformis and estimating the proportion (if any) which comprises a whip-like filament (‘d’ in Figure 1). Materials and methods Top ↑ Only some methods which are not more or less universal laboratory proceedings are included below. Faecal cultures and harvesting of infective larvae There are numerous different methods for preparing faecal cultures. However, in this laboratory they are prepared as follows by a modification of the technique of Roberts and O’Sullivan (1950), as described by Reinecke (1973) for all but the various lungworm and Nematodirus species. In short, sheep faecal pellets are thoroughly crumbled before being mixed with sufficient vermiculite chips to yield a crumbly mixture which is lightly compacted, using non-porous stampers, to a depth of about 5 cm in wide-mouthed glass jars of approximately 1 L capacity. A hole is left in the centre of the culture by holding a stamper vertically in the centre of the jar whilst the mixture is lightly compacted around it. The culture is moistened sufficiently to ensure that it does not dry out whilst being incubated, but without it becoming water-logged. Thereafter, the jar is incubated in the dark at 26 °C – 28 °C for 5–7 days, during which time it is checked periodically and moistened if necessary. Note that, as discussed by Van Wyk et al. (2004), the length of both the larva and its STE may vary in relation to the amount of moisture in the culture medium (Rossanigo & Gruner 1996), so this needs to be standardised for consistent results. After the 7-day period of incubation of the culture, the inside of the jar is sprayed lightly with water from a wash bottle before being placed in bright light that stimulates the L3 to migrate up the inner surfaces of the vessel’s walls. The culture is harvested repeatedly over several days by holding the jar at a slant with the mouth pointing downwards and then spraying the inner walls with a wash bottle and allowing the larval suspension to drain into suitable containers. As Gaigeria pachyscelis and Bunostomum phlebotomum do not migrate readily up the walls of the culture jars, they are harvested by filling the culture jar with water, allowing it to stand for a few minutes to allow the air to escape from the culture, adding water to the jar until the water meniscus protrudes above the lip of the jar, placing an overturned Petri dish over the mouth of the jar and keeping the Petri dish in position whilst the jar is inverted (Borgsteede & Hendriks 1974; Eckert 1960). Water is then added to the Petri dish and the rim of the jar is lifted slightly from the bottom of the dish on one side by slipping two glass microscope slides under it. The preparation is left for a few hours for L3 to migrate into the water and to settle, before the water in the Petri dish is removed with a pipette for larval identification and counting. Because Nematodirus spp. ova need up to 14 days to hatch, fungal overgrowth commonly makes the above culture method unsuitable for members of this genus. Thus the ova are initially concentrated in relatively little faecal suspension by sieving through a combination of sieves with apertures of different sizes. So-called Visser sieves (a set consisting of three tubular sieves fitting one into the other) (Malan & Visser 1993) are ideal, with sieve openings of about 200 mm in the inner tube, 150 mm in the middle and 38 mm – 60 mm apertures in the outer tube sieve. The latter sieve is capped at the bottom to accumulate the contents in about 20 mL of water, whilst a tap is provided in the cap for drainage. The faecal sample is placed in the inner tube sieve before being thoroughly washed with a rosette of spray using an adjustable garden spray on a hose, with the effluent passing through all three tubes. The inner tube sieve is then removed and the contents of the middle tube washed similarly before it is removed in turn and the process repeated for the outer tube. Nematodirus spp. and Marshallagia marshalli ova are retained in suspension in the inner tube and are cleaned further by progressive removal of the faecal particles through alternate differential sedimentation and flotation, respectively in water and 40% sucrose solution, ending with a watery suspension (Reinecke 1973). For final ‘cleaning’ of the ova, the suspension of ova and faecal particles is poured into a flat-bottomed glass crystallising dish to a depth of about 3 cm and left to stand for about a minute before the contents of the dish are carefully poured at a slow and even pace into a second dish of the same sort. The ova, having a higher relative density than most of the faecal particles, sink relatively rapidly to the bottom and many of them adhere to the dish, whilst the majority of the faecal particles remain in the suspension that is poured off. The ova are harvested by washing into a beaker, with the use of a wash bottle. The process is repeated until few ova, appearing to the naked eye as a whitish, granular layer on the bottom of the dish, are visible after decantation. The cleansed Nematodirus spp. ova are next cultured in water containing a pinch of potassium dichromate (K2Cr2O7) to control fungal growth until the L3 have emerged. Continual aeration of the suspension seems to be beneficial for stimulating hatching. For Nematodirus spathiger, the yield of L3 can be improved considerably by storing the ova at about 4 °C for a week before incubation (Viljoen 1972). In the case of Nematodirus battus, formalin is added weekly to the culture over the 5–6 weeks of incubation to a final concentration of 1%, incubating the ova for an hour and then washing them on a 53 μm sieve before continued incubation (F. Jackson pers. comm., 1998 – Anonymous, ‘Moredun Research Institute Parasitology Division standard operating procedures’). Nematodirus spp. ova can also be ‘hatched’ artificially (F. Jackson pers. comm., 1998 – Moredun SOPs): well cleansed, fully embryonated ova (i.e. on the point of hatching) are concentrated to obtain about 1 mL of solid material (eggs) per 10 mL of water. About 0.25 mL of egg suspension is pipetted in a line on a thick glass base plate measuring 300 mm × 200 mm × 8 mm, covered with a similar ‘crushing’ glass plate and firm pressure is applied on the top plate until the ova are felt to crack. Stereoscopic examination should reveal that almost all the eggs have cracked, with larvae emerging. The larvae emerge fully when the preparation is re-suspended in water. Larva preservation Most L3 that die from natural causes or are killed (e.g. with heat) become granular and less translucent in appearance and tend to curl up, such as when killed with formalin. However, if alive, they can be relaxed and preserved practically unchanged in appearance for training and reference purposes. Formalin is added to a final concentration of about 1% – 2% to the suspension of larvae, which are then killed by heating the suspension to 55 °C – 57 °C for about a minute (note that most of the common infective larvae can survive for even some hours in much higher concentrations of formalin than the amount described above). Larvae killed and preserved in this way do not curl up, largely retain their brightly translucent appearance and their internal structures are more clearly discernable than those of L3 killed by heating alone (Van Wyk et al. 2004). Larva preparation for identification A drop of larval suspension is deposited on a glass microscope slide and the larvae killed with Lugol’s iodine solution that is pre-diluted to a level where it takes a few minutes before the L3 become darkly stained. The reason for this is that it is more difficult to observe internal structures of larvae (such as the shape of the oesophagus that is important in some cases) and also to differentiate free-living nematodes from L3 of Bunostomum and Gaigeria spp. (which rapidly stain almost uniformly brown over their entire length) from the majority of the others, in which the cranial part of the larva initially stains considerably less intensively than the rest. Larva identification Note that, in this article, the tip of the cranial extremity of a larva is referred to as its ‘head’ and the caudal tip as its ‘tail’ (Figure 1) and the free sheath beyond the tail tip as the STE. Morphological identification of L3 of most parasitic nematodes is based principally on examination of the caudal and cranial extremities, although other features such as the length or shape of the oesophagus or cranial refractile spots are important in some genera. Note, however, that once exsheathed, L3 of relatively few genera can be differentiated. Even when a space has formed between the cranial tip and the sheath of an aging larva, the characteristic shape of the head appears distorted and more squared than usual, thus increasing the chances of incorrect identification. Length of sheath tail extension The length of the STE is a very important criterion for identification and, to facilitate its application in larval differentiation, the STE of every larva being evaluated is related to that of Tr. colubriformis and Tr. axei. To this end, the length of the STE (‘c’ in Figure 1) of Tr. colubriformis and Tr. axei (± 33 mm) is represented by ‘X’, to which that of each L3 encountered in a culture is related as follows: Length of STE of L3 being identified (‘c’ in Figure 1) = STE / ‘X’. Proportion of sheath tail extension comprising a filament If the STE ends in a narrow, thin filament (‘d’ in Figure 1), the proportion of the total length of the STE that this comprises is calculated, although with practice it can usually be estimated without the need for measurement. Note, however, that there is no exactly definable point of transition from the sheath filament to the cranial portion of the STE per genus or species; it is invariably a more or less gradual process, with no precise point of inflexion. On the other hand, because of relatively large differences in filament proportion between those species or genera such as Chabertia ovina and Oesophagostomum spp. that are difficult to differentiate (Table 1), this fact does not detract from its usefulness as a criterion for identification. Individual values in Tables 1 and 2 were derived as described by Van Wyk et al. (2004). In some cases, the lengths of the STEs were not listed in the papers reviewed by them, but could be calculated from the tables, estimated from photographs and/or figures drawn to scale, or could be calculated from histograms (Keith 1953). Differential larval count Top ↑ Identification procedure Firstly, a stage micrometer is used to determine, for each microscope objective lens, the number of divisions of the graticule in the ocular lens that span 33 mm; that is, the mean length of the STEs of Tr. axei and Tr. colubriformis, defined as ‘X’ for the purposes of the present system of identification (Table 1). Then the STEs of the L3 encountered in the diagnostic samples are compared, in turn, to the number of divisions (usually four divisions at 100× magnification) recorded for Tr. colubriformis and Tr. axei. Whilst the experienced person will use 10× ocular and objective microscope lenses (i.e. about 100× total magnification) or even somewhat less for the largest part of each differential count, about double this magnification will be necessary for the exceptional larval specimens that are difficult to identify, as well as for routine differentiation by the novice. Conventionally, the first 100–200 L3 encountered per count are identified for estimating the proportion of a given sample which each genus comprises. Whilst L3 can generally be identified only to genus, this is not absolute. Because the L3 of Trichostrongylus spp. of small ruminants are difficult to differentiate from those of Teladorsagia spp., they are commonly grouped during the count. However, when exsheathed, L3 of Nematodirus spp. and intestinal Trichostrongylus spp. can be differentiated from those of Tr. axei and Teladorsagia spp. in having digitate appendages on the tail, whilst the others have none (Figure 2 [McMurtry et al. 2000] and Figure 3). TABLE 1: Measurements of third-stage larvae of small ruminants, including sheath tail extensiona, �X�-values and the proportion of the sheath tail extension comprising a filament. TABLE 2: Measurements of third-stage larvae of cattle, including sheath tail extensiona, �X�-values and the proportion of the sheath tail extension comprising a filament. Whilst exsheathing of intestinal Trichostrongylus spp. aids in their identification, larvae that are exsheathed are often difficult to differentiate, as mentioned above. This impasse of having to differentiate some L3 after they have been exsheathed whilst others must perforce be ensheathed can be overcome to some extent by conducting differential counts in two steps. Initially, ensheathed Trichostrongylus, Teladorsagia species are grouped, whilst the rest are identified to the level of genus or species. Thereafter, as a second step, the L3 are exsheathed and only those with specific digitate terminal caudal appendages (Figure 2, intestinal Trichostrongylus spp.) are differentiated from the rest of the first 100–200 encountered. Subsequently, the proportion of Teladorsagia spp. can be computed as follows: • Step 1: Do differential count of ensheathed L3 and let % Teladorsagia spp. + Trichostrongylus spp. = x. • Step 2: Exsheathe the L3 and repeat differential count. Let % intestinal Trichostrongylus spp. (McMurtry et al. 2000) = y. Then % Teladorsagia spp. + Tr. axei = x - y. Unfortunately, with the above approach it is not possible to differentiate Tr. axei from Teladorsagia spp., but if it is important to do so, the method of Lancaster and Hong (1987) can be employed as follows during the first step for a rough estimate, whilst keeping in mind that Cabaret (pers. comm., 2003) experienced the Lancaster and Hong (1987) technique to have a wide margin of error (see discussion below): • Step 1: Do differential count of ensheathed L3 and let % Teladorsagia spp. (Lancaster & Hong 1987) = x; and let % Trichostrongylus spp. (Lancaster & Hong 1987) = y. • Step 2: Repeat differential count after having exsheathed the L3 and let % intestinal Trichostrongylus spp. (McMurtry et al. 2000) = z. Then % T. axei = y - z. FIGURE 1: Diagram of a nematode infective larva, depicting (a) total length, (b) tip of larva tail, (c) sheath tail extension and (d) filament. FIGURE 2: Identification to species level of Trichostrongylus spp., based on differences in the morphology of the tips of the larva tails: (a, b) Trichostrongylus colubriformis, (c, d) Trichostrongylus vitrinus, (e) Trichostrongylus axei and (f) Teladorsagia circumcincta. Ethical considerations Top ↑ This article is based on research conducted in the 1970s and early 1980s. Whilst it was carried out strictly in accordance with ethical considerations overseen by the management of the Onderstepoort Veterinary Research Institute, at that stage there were no national or international guidelines for work of this nature of which the authors were aware. In 2004, a novel method of larvae evaluation was identified and described from the work of Van Wyk et al. (2004) and the present study illustrates this in terms of the differences between the larvae, whilst, at the same time, accurately drawing the STE filaments (this having been developed only recently, but without the need for further research in animals). Results and discussion Top ↑ Differentiation of larvae Most importantly, as emphasised by Mönnig (1931), is the selection of only those points of comparison between L3 of the various genera and species that will enable swift identification with the minimum number of measurements. It is also necessary to acquaint yourself with the variation in the appearance of the various features under different depths of focus of the microscope. It is exceedingly difficult to photograph larval STEs such that both the tip of the STE and the rest of the caudal extremity of a given larva is in focus simultaneously. Hence the excellent photographs in the papers of Corticelli and Lai (1964) and Henriksen (1972), and to some extent also of Keith (1953), deserve particular mention, as these workers succeeded particularly well, and their photos can be put to very good use when training inexperienced persons to identify L3. On the other hand, some of the modern electronic photomicroscopes are able to integrate a series of photos at different depths of focus into a composite picture with the entire sheath tail in focus and this could be used fruitfully to this end. Tables 1 and 2 contain summaries of the mean measurements and corresponding ‘X’-values of the different common worm genera and/or species (see Van Wyk et al. 2004, Tables 1–7, for details gleaned from the literature). L3 of parasitic nematode genera are illustrated in this article in Figures 2–13. As discussed by Van Wyk et al. (2004), in most cases where drawings were published previously, the shapes of the heads (cranial extremities) of the larvae and the proportional lengths of the filamentous portions of the STEs were not drawn accurately to scale. Many of the differences between worm genera are very small, making it difficult to observe and even more difficult to draw accurately. There are notable exceptions, such as the drawings of Borgsteede and Hendriks (1974), which are relatively accurate regarding the morphology of both the heads and STEs of the L3; yet, identification remained so difficult, especially for the inexperienced, that another morphological feature was sought that could simplify the process. The sheath tail filament presented this possibility. FIGURE 3: Terminal appendages of Nematodirus spp. exsheathed third-stage larvae: (a) Nematodirus spathiger, lateral view, (b) Nematodirus spathiger, dorso-lateral view, (c) Nematodirus filicollis, lateral view, (d) Nematodirus filicollis, ventro-lateral view, (e) Nematodirus battus, lateral view and (f) Nematodirus abnormalis, lateral view. FIGURE 4: Third-stage larvae of common nematodes of small ruminants, measured in micrometres (�m). FIGURE 5: Cranial and caudal extremities of third-stage larvae of common nematodes of small ruminants, measured in micrometres (�m). FIGURE 6: Third-stage larvae of common nematodes of cattle, measured in micrometres (�m). FIGURE 7: Cranial and caudal extremities of third-stage larvae of common nematodes of cattle, measured in micrometres (�m). FIGURE 8: Cranial and caudal extremities of ensheathed third-stage larvae of Nematodirus spp., measured in micrometres (�m). FIGURE 9: Differentiation of third-stage larvae of Trichostrongylus spp. (left) and Ostertagia spp. (right), depicting (a) initial point of inflexion craniad and (b) �shoulder� of Ostertagia spp. FIGURE 10: Exsheathed third-stage larva of Oesophagostomum columbianum with a total of 20 or 21 intestinal cells (larva thawed after having been frozen in liquid nitrogen). The potential of the STE filament for differentiation of L3 was not recognised previously. Most earlier workers either did not take it into consideration as a distinguishing feature, or it was mentioned in general without investigating its potential for identifying L3 to the level of genus or species (Corticelli & Lai 1964; Gibbons et al. 2012). This omission could perhaps be ascribed to the fact that, as mentioned, the transition between the filament and the rest of the STE is not sharp and thus cannot be pinpointed with certainty, especially because it is also affected by the depth of focus of the microscope. With few exceptions, such as some Nematodirus spp. and intestinal Trichostrongylus spp., the infective larvae of the common nematodes of domestic ruminants can be identified only to genus level. However, as differences between species of a given genus in characteristics such as pathogenicity and, to some extent, susceptibility to anthelmintics are generally small, this limitation is seldom a serious disadvantage. Morphological differences between some genera (e.g. Trichostrongylus spp. and Teladorsagia spp.) are so small that the ‘X’ system is ineffective for differentiation and the STEs have no filaments. However, these are the exceptions, as the differences are mostly large enough to make it possible after a few measurements (in divisions on the graticule) of L3 in a mixed culture to judge the various ‘X’-values without the necessity for many (if any) further measurements. Experience has shown that even relatively small differences can be recognised without recourse to measurement. For instance, whilst this system was in the early stages of development we became alerted, without having to resort to measurements, to a pure culture of Trichostrongylus falculatus (the sheath tail of which differs from the common Trichostrongylus spp. by only 0.5 ‘X’) when faecal samples were submitted after a field outbreak of deaths in sheep in the Free State Province. On the other hand, variations within species or genera (Tables 1 and 2) must be kept in mind and it remains essential to take note of and to use other morphological features, such as the shape of the head (Figures 5–8, 14 and 15) and the refractile bodies in the heads of Cooperia spp. (below), in addition to the ‘X’ system. It is also advisable to have L3 of at least Tr. colubriformis and/or Tr. axei, but preferably of more genera, in pure culture available in each laboratory where either diagnostic or research differential larval counting is performed. Only small numbers of these L3 are required at a time, with the result that a single batch killed and preserved as described above can suffice for years. Figures 14 and 15 are organograms that can function as illustrated, interactive keys for the stepwise morphological identification of common nematode L3 of small ruminants and cattle, respectively. They were compiled largely for the purpose of training of the inexperienced and are intended for use together with the various figures depicting prominent distinguishing features of the morphology of the L3 concerned. Salient features of L3 of the common nematode genera and/or species Trichostrongylus spp. Whilst very similar, there are some distinguishing features between different Trichostrongylus species of domestic ruminants, for instance in length of STE (e.g. ‘X’ and no filament in Tr. colubriformis and Tr. axei and 1.7 ‘X’ in Tr. falculatus and Trichostrongylus rugatus) (O’Callaghan 2004; Van Wyk et al. 2004) and the presence or absence of digitate appendages on the caudal extremity of the larvae (Figure 2) (McMurtry et al. 2000). Common to all the Trichostrongylus species included in this article is that the STE is without a filament and tapers so sharply that it resembles the point of a sharpened wooden pencil. The very short STE of Tr. colubriformis and Tr. axei is used as the basis of the classification system (Van Wyk et al. 2004). When exsheathed, the L3 of Tr. axei resemble those of Teladorsagia spp. in that the tip of the tail is smooth, in contrast to the irregular protuberances mentioned for intestinal Trichostrongylus spp. However, the differences can be discerned only at high magnification and are usually visible only in larvae that are exsheathed. Hence, as mentioned above, this feature requires a second step in the differential larval count procedure. Ostertagia and Teladorsagia spp. Small ruminants: The STE of the Teladorsagia spp. of small ruminants overlaps considerably in length with that of Trichostrongylus spp. and is very similar in appearance, resembling a sharpened pencil point, and both are without a terminal filament (Table 1). Added to this is that, as mentioned, the tip of the tail of the Teladorsagia spp. L3 is smooth, similar to that of Tr. axei. According to Lancaster and Hong (1987), the head of ovine Teladorsagia species has a slight ‘shoulder’ close to its cranial tip (illustrated in Figure 9), whilst that of Trichostrongylus spp. does not. This is fully described and depicted in Lancaster and Hong (1987) and Van Wyk et al. (2004). Note, however, that J. Cabaret (pers. comm., 2003) reported an average of 30% incorrect identifications with use of this method for differentiating Tr. colubriformis and Teladorsagia circumcincta in mixed culture. Whilst Tr. axei and Te. circumcincta do differ markedly in total length (with respective means of 720 mm and 820 mm), it is time-consuming to do such measurements. Furthermore, the lengths of the L3 of Trichostrongylus spp. and Teladorsagia spp. overlap to a considerable extent (O’Callaghan 2004), thus making it a relatively impractical for accurate discrimination. FIGURE 11: Exsheathed third-stage larva of Chabertia ovina, with a total of 32 intestinal cells (larva thawed after having been frozen in liquid nitrogen). FIGURE 12: Tail morphology of lungworm larvae of five genera: (a) Muellerius capillaris, (b) Protostrongylus rufescens, (c) Cystocaulus ocreatus, (d) Dictyocaulus filaria and (e) Neostrongylus linearis, with (i) and (ii) illustrating the different types of appendices to the larva tails. Cattle: In this host species, in contrast to the situation in small ruminants, there is small chance of confusing the STEs of Ostertagia ostertagi and Trichostrongylus spp. L3. At slightly more than 2 ‘X’, the STE of L3 of Os. ostertagi is twice as long as that of the common Trichostrongylus spp. and the presence of a short filament serves further to differentiate them from the L3 of both Te. circumcincta and Trichostrongylus spp. (Tables 1 and 2). Another useful distinguishing feature is that the STE of Os. ostertagi ends in a blunter tip than that of Haemonchus placei (Borgsteede & Hendriks 1974) (Figures 6 and 7). Haemonchus spp. As discussed by Van Wyk et al. (2004), there has been confusion in the past concerning the validity of H. placei as a separate species from Haemonchus contortus, despite clear morphological and/or biological distinguishing features between the two both in the L3 and adult worms. The confusion was compounded by cross-infectivity of both species to sheep and cattle. The adults of the two species are indeed relatively difficult to differentiate morphologically, but with use of the novel approach to differentiation presented now, this should not apply to the L3. Whilst the infective larva of H. contortus of small ruminants has an STE with a length of 2.2–2.7 ‘X’ and a filament comprising 10% – 15% thereof, the corresponding values of H. placei of cattle are 2.7–4.0 ‘X’ and ± 20% (Figures 4–7 and Tables 1 and 2). On the other hand, Borgsteede and Hendriks (1974) discuss the possibility of confusion between the L3 of H. placei and of Os. ostertagi in cattle and point out the respective bullet-shaped and flatter heads and much finer and blunter STE tips of Os. ostertagi and H. placei (see Figures 6 and 7 in this article, as well as subsection 3.1.3. of Van Wyk et al. 2004 and, particularly, Figure 3 of Borgsteede & Hendriks 1974). Added to this is that the filament comprises a larger proportion of the STE of H. placei than it does in Os. ostertagi (Table 2) (Van Wyk et al. 2004) and, as discussed by Van Wyk et al. (2004), the intestine of Haemonchus spp. is reported to end caudally in two terminal cells, compared to only one in Ostertagia spp. Cooperia spp. Most striking is the presence of two unique refractile bodies in the head of the L3 of Cooperia spp. (Figures 4–7), constituting an important distinguishing feature from those of other genera. On the other hand, the STEs of Cooperia pectinata and Cooperia punctata of cattle somewhat resemble those of Os. ostertagi and H. placei, all having a filament of about 20% (Table 2). However, in addition to the refractile bodies of Cooperia spp., the head of the L3 of Os. ostertagi is considerably more squared than that of Cooperia spp. or H. placei. In contrast, the STE of Cooperia oncophora in cattle is ± 3 ‘X’, more closely resembling the L3 of H. placei than that of Os. ostertagi. Another distinguishing feature of C. oncophora is that the caudal tip of the sheath of C. oncophora is clearly perceptible, whereas that of C. punctata ‘appears to vanish into nothingness’ (Borgsteede & Hendriks 1974), or is ‘refractile in appearance’ (Anonymous 1977). Borgsteede and Hendriks (1974) also describe the head of the L3 of C. oncophora to be somewhat broader than that of C. punctata, although we have found this difference to be difficult to visualise. FIGURE 13: Morphology of the cranial extremities (heads) of free-living nematodes: (a) Tylenchida, (b) Dorylaimida and (c) Rhabditida, depicting, (i) stoma, (ii) stylet, (iii) oesophagus, (iv) valve and (v) nerve ring. FIGURE 14: Organogram for identifying gastrointestinal nematode and lungworm larvae of small ruminants, including a general description of free-living nematodes. FIGURE 15: Organogram for identifying gastrointestinal nematode and lungworm larvae of cattle. Notably, as reviewed by Van Wyk et al. (2004), the mean lengths of the STEs of C. oncophora L3 cultured from sheep differ significantly from those from cattle. The respective lengths are about 73 mm (2.4 ’X‘, Table 1) and 94 mm (3.1 ’X‘, Table 2), with corresponding ranges of 62 mm – 82 mm and 65 mm – 116 mm, hence with little overlapping in the lengths of their STEs, as confirmed by the fact that Hansen and Shivnani (1956) recorded only one measurement of less than 79 mm for C. oncophora from cattle and Dikmans and Andrews (1933) recorded a maximum of 82 mm for this species from sheep. The Cooperia curticei L3 of sheep has an STE more closely resembling that of C. pectinata and C. punctata than that of C. oncophora, but it is important to note that, as mentioned, the STE of the latter is reported to be shorter in small ruminants than in cattle (see above). The hookworms, Bunostomum spp. and Gaigeria pachyscelis Hookworm L3 (B. phlebotomum in cattle, and Bunostomum trigonocephalum and G. pachyscelis in sheep and goats) are characteristically small in size, being almost 100 mm less in total length than those of H. contortus, the second shortest of the common species or genera. They stain uniformly dark with iodine, in contrast to the L3 of other nematodes that stain light brown cranially and dark brown caudally shortly after addition of the iodine. The STEs vary from 2.4 ’X’ for B. phlebotomum L3 to 4.4 ’X‘ for G. pachyscelis, each with a filament comprising about 50% of the STE. The oesophagus has a prominent bulb caudally that is most easily observed in the live, active L3, but difficult to visualise after any but very short periods of staining with dilute iodine solution. The L3 of the following three genera are set apart from the rest by having conspicuously long STEs. Oesophagostomum spp. and Chabertia ovina Helminths of these two genera occur widely disseminated in the world, but Ch. ovina occurs much less commonly than the other. Whilst in small ruminants Oesophagostomum venulosum occurs in Mediterranean-type climate and Oesophagostomum columbianum under warmer subtropical and tropical conditions, in cattle Oesophagostomum radiatum is practically universally disseminated. A characteristic of the infective larvae of both genera is that they have relatively long STEs (Table 1 and 2). However, note that the filament of L3 of Oesophagostomum spp. has been observed occasionally to break off, resulting in a much different appearance (Mönnig 1931; J. Van Wyk pers. obs., 1996). Whilst apparently not as yet reported for other species, presumably this is also a possibility and should be kept in mind for both Ch. ovina and some others, such as L3 of Nematodirus spp. with long STE filaments. The L3 of Oesophagostomum and Chabertia spp. resemble one another so closely that they are described as practically indistinguishable by some authors. However, much of the confusion appears to have resulted from misidentification in the first place, because the numbers and appearance of the intestinal cells, as well as distinguishing features of the STEs present ready methods of differentiation. Number of intestinal cells: Whilst, in some instances, both Oesophagostomum and Chabertia genera are described and/or depicted as having 32 rectangular intestinal cells or as being indistinguishable (Anonymous 1977; Eckert 1960; Gibbons et al. 2012), in others where only Oesophagostomum spp. are described, they are listed as having or perhaps having up to 32 cells (Mönnig 1931). In contrast, Dikmans and Andrews (1933) and Borgsteede and Hendriks (1974) correctly describe Ch. ovina to have about 32 and Oesophagostomum spp. about 20 intestinal cells, although the latter authors were uncertain whether some L3 of Oesophagostomum could have up to 32 cells. Unfortunately it is usually only in the very newly developed infective larvae that the shapes of the intestinal cells are clearly discernable, but even if not, it is sometimes possible to count the cells by examining the granular cell content under relatively high magnification. In addition, a further method has been found to illustrate the number of cells per genus very effectively; when exsheathed L3 of Oe. columbianum and Ch. ovina are frozen in liquid nitrogen and subsequently thawed, a bubble can generally be seen in each intestinal cell, very effectively differentiating the two genera (Figures 10 and 11, re-photographed from Van Wyk 1977). The photographs clearly illustrate the difference in numbers of cells, being 18–22 in Oe. columbianum and 28–32 in Ch. ovina. Intestinal cell shape: The intestinal cells of the L3 of the two genera under discussion also differ dramatically in shape, being triangular in Oesophagostomum spp. and rectangular brick-shaped in Ch. ovina (Figures 4, 10 and 11). However, as discussed, the outlines and thus shapes of the cells are frequently not discernable in any but newly developed larvae. Sheath tail extension filament: It is in the STE that the most consistent means of differentiation of Oe. columbianum and Ch. ovina L3 lies, not in its length, but mainly in the proportion of the length comprising the filament, being about 50% – 60% in the former and 25% in the latter (Table 1). Hence, despite it being difficult to pinpoint the exact point of inflexion between the filament and the cranial, non-filamentous portion of the STE, the margin of error resulting therefrom is small enough to allow accurate discrimination. In summary, Oesophagostomum spp. and Ch. ovina L3 respectively have ± 18–22 and 28–32 triangular intestinal cells, the lengths of the STE are ± 5 ‘X‘ and 4 ‘X’ and the filaments constitute from 40% to 70% of the STE by species in the former and 25% in the latter (Figures 5 and 7; Tables 1 and 2). Nematodirus spp. The commonly encountered species are N. spathiger, Nematodirus filicollis and Nematodirus abnormalis of small ruminants, Nematodirus helvetianus of cattle and N. battus of lambs and also calves. When sheathed, Nematodirus spp. L3 are conspicuously longer than those of other nematode genera. They have only eight large intestinal cells, a considerably longer STE (except for N. battus) and prominent digital appendages on the tails of the larvae (Figure 3). It is seldom necessary to identify L3 of Nematodirus spp. in routine faecal cultures because the ova of the genus require at least two weeks to hatch, whilst faecal cultures are usually harvested after 5–7 days and require pre-exposure to low temperatures to be able to hatch (Viljoen 1972). However, because Nematodirus ova are much larger than, and hence easily distinguished from, those of most other parasitic nematodes, they can be recorded separately in routine faecal egg counts and any Nematodirus L3 which may be encountered in cultures, are ignored and not included in the differential larval counts. It is important to note, however, that Nematodirus ova can be confused in general appearance with those of M. marshalli, the ova of which are similarly considerably larger than those of most of the parasitic gastrointestinal nematodes (Soulsby 1982). Also, whilst the eggs of the other common Nematodirus species are more or less oval in shape, that of N. battus is considerably smaller and much more oblong, resembling ‘oversize’ eggs of the other common gastrointestinal strongyles. Strongyloides papillosus The L3 of this species are exceptionally thin, the oesophagus comprises about 40% of the total length, the tip of the tail is bifid and it has no covering second sheath as do the L3 of the other genera, hence also no STE. At the lower magnifications usually used for routine larva identification, it is not possible to see that the tip of the tail is bifid, but it does have the appearance of an STE, of which the tip of the filament has broken off. Misidentification may occur if only the tail of this larva is examined instead of the entire larva, because the disproportionately long oesophagus will be missed and it sometimes seems – mistakenly so – as if it does have an STE. Dictyocaulus spp. Both Dictyocaulus filaria of small ruminants and Dictyocaulus viviparus of cattle are ovo-viviparous. Hence, their ova hatch in their respective hosts and the L1 are passed in the faeces. For diagnosis, the L1 are recovered by Baermannisation, otherwise a few faecal pellets or a blob of faeces can be placed in water in a Petri dish and the surrounding water observed under a stereo microscope for larvae migrating out of the faeces. Dictyocaulus spp. larvae are small in size and very lethargic, the tail ends caudally in a smoothly rounded tip (‘d’ in Figure 12), no STE is discernable and the intestinal cells are indistinct and usually brown in colour. A striking difference between L1 of D. filaria and D. viviparus is a conspicuous bulbous thickening of the sheath on the head of the former that is absent from D. viviparus. Similar to the infective larvae of Nematodirus spp., larvae of Dictyocaulus spp. are seldom encountered in representative numbers in routine larval cultures, but for a different reason; they migrate poorly out of such cultures unless collected as described for the recovery of hookworm larvae. Striking photos of D. filaria and D. viviparus larvae can be seen on the website of Gibbons et al. (2012). Protostrongylid lungworm larvae Muellerius, Cystocaulus, Neostrongylus and Protostrongylus spp. are commonly present in sheep faeces in Europe (Cabaret 1986), whilst Varestrongylus pneumonicus, which is found in small ruminants in Asia, is recorded only in roe deer in temperate Europe. The L1 of the protostrongylids are recovered from faeces using a Baermann-derived technique (Cabaret, Dakkak & Bahaida 1980; also various textbooks, e.g. Hansen & Perry 1994). The morphology of the tails of some of the larvae is shown in Figure 12, but persons who encounter these L1 more commonly should study the more detailed descriptions in Van Wyk et al. (2004) and Gibbons et al. (2012). Free-living nematodes Cultures of faeces picked up from the ground are often contaminated with free-living nematodes, which then tend to dominate faecal cultures to the extent that it is almost impossible to do a differential parasitic nematode larval count. Thus it is preferable to collect faeces from the rectum for cultures, or from bags hung on the animal, although contamination has also been described despite the use of faecal collecting bags (Van Wyk et al. 2004), in which case it was overcome by shearing and thoroughly washing the buttocks of the animals. It is important to note that, even though they often resemble the L3 of parasitic nematodes, most of the free-living nematodes encountered in faecal cultures are adults and not larvae. In contrast with the majority of the parasitic larvae, the commonly encountered free-living nematodes stain uniformly, extremely dark brown with iodine, are relatively thick and cigar-shaped, have a rhabditiform oesophagus (i.e. with two conspicuous bulbs caudally) and a long tail with no covering sheath. However, the genera differ markedly from one another (as briefly indicated by Van Wyk et al. 2004) and these nematodes differ to such an extent from the parasitic larvae that there should seldom be confusion. Conclusion Top ↑ There are dwindling numbers of persons trained in ‘conventional’ helminthological techniques, such as larva identification, which is relatively difficult to learn even when persons with the required skill are available as mentors to the inexperienced. In addition, whilst the full range of pure cultures (and thus larvae) of the common gastrointestinal nematodes of both sheep and cattle were generally available previously, few laboratories maintain these any longer. Thus, it is essential that every possible aid, such as the newly described use of the proportion of the STE in identification, be available to those who need to learn to differentiate infective larvae obtained by faecal culture. Acknowledgements Top ↑ This work was supported by the EU ‘PARASOL’ (EU-FP6) and ‘RISC-NET’ projects, the latter under the ‘CIDLID’ call for applications, funded by a partnership between the Biotechnology and Biological Sciences Research Council, the Department for International Development and the Scottish Government. Hennie Gerber (now deceased) maintained pure nematode cultures and Lynne Michael and Regina Alves were instrumental in preparations. Jacques Cabaret was the source of information on lungworm larvae, which are described in more detail in Van Wyk et al. (2004). Ian Carmichael went to much trouble to locate original material from trials of Beveridge, Martin and Pullman (1985). Michael O’Callaghan drew the ‘f’ diagram in Figure 3. Hervé Mauleon helped with descriptions of free-living nematodes. Ron Kaminsky, Frank Jackson, Jacques Cabaret, Jacques Cortet, Eric Morgan and Flip van Schalkwyk supplied L3 of a variety of species. Competing interests The authors declare that they have no financial or personal relationships which may have inappropriately influenced them in writing this article. Authors’ contributions J.A.v.W. (University of Pretoria) was responsible for developing the novel approach to morphological identification of infective larvae of the common gastrointestinal nematode genera of small ruminants and cattle and wrote the manuscript. E.M. (University of Pretoria) was responsible for all the art work and finishing of the article. References Top ↑ Anonymous, 1977, ‘Examination and identification of third-stage larvae of nematodes and of the immature stages of trematodes in the snail’, Manual of Veterinary Parasitological Laboratory Techniques, Reference Book 418, 36–39, Ministry of Agriculture, Fisheries and Food, London. Beveridge, I., Martin, R.R. & Pullman, A.L., 1985, ‘Development of the parasitic stages of Nematodirus abnormalis in experimentally infected sheep and associated pathology’, Proceedings of the Helminthological Society of Washington 52, 119–131. Boch, J. & Supperer, R., 1983, Veterinärmedizinische Parasitologie, Paul Parey, Berlin. Boev, S.N., 1984, ‘Protostrongylids’, Fundamentals of Nematology 25, Oxonian Press, New Delhi. Borgsteede, F.H.M. & Hendriks, J., 1974, ‘Identification of infective larvae of gastrointestinal nematodes in cattle’, Tijdschrift Diergeneeskunde 99, 103–113. Cabaret, J., 1986, Répartition géographique des protostrongylidés des ovins. Fréquence et importance de cette parasitose pulmonaire en Europe et en Afrique du Nord [Geographical distribution of protostrongylids. Frequency and importance of this lung parasitosis in Europe and North Africa]. Épidémiologie et Santé Animale 10, 61–72. Cabaret, J., Dakkak, A. & Bahaida, B., 1980, ‘A technique for the evaluation of the number of lungworm first stage larvae in sheep faeces’, British Veterinary Journal 136, 296–298. PMid:7388593 Christie, M. & Jackson, F., 1982, ‘Specific identification of strongyle eggs in small samples of sheep faeces’, Research in Veterinary Science 32, 113–117. PMid:7201151 Corticelli, B. & Lai, M., 1964, La diagnosi di tipo d’infestione nella strongilosi gastro-intestinale del bovino in Sardegna con le larve infestive [Diagnosis of the infestation type in gastro-intestinal strongylosis of cattle in Sardinia by differentiation of the infective larvae]. 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Faecal examination of farm animals for helminth parasites’, viewed 19 October 2012, from http://www.rvc.ac.uk/review/Parasitology/Index/Index.htm Hansen, J. & Perry, B., 1994, The epidemiology, diagnosis and control of helminth parasites of ruminants, pp. 83–90, International Laboratory on Animal Diseases, Nairobi. Hansen, M.F. & Shivnani, G.A., 1956, ‘Comparative morphology of infective nematode larvae of Kansas beef cattle and its use in estimating incidence of nematodiasis in cattle’, Transactions of the American Microscopical Society 75, 91–102. http://dx.doi.org/10.2307/3223659 Henriksen, S.A., 1972, Undersogelser verdrorende lobe-tarmstrongylider hos kvaeg. I. Nogle forelobige erfaringer med L3-analyser [Investigations concerning bovine gastro-intestinal strongyles. I. Preliminary results of L3 analyses]. Nordisk Veterinaer Medicin 24, 49–55. PMid:4666546 Keith, R.K., 1953, ‘The differentiation of the infective larvae of some common nematode parasites of cattle’, Australian Journal of Zoology 1, 223–235. http://dx.doi.org/10.1071/ZO9530223 Lancaster, M.B. & Hong, C., 1987, ‘Differentiation of third stage larvae of “ovine Ostertagia” type and Trichostrongylus species’, The Veterinary Record 120, 503. http://dx.doi.org/10.1136/vr.120.21.503, PMid:3604011 Malan, F.S. & Visser, P.S., 1993, ‘Faecal egg counts by a new method using tube filters’, Proceedings of the 14th International Conference of the World Association for the Advancement of Veterinary Parasitology (WAAVP), Cambridge, UK, 08–13 August 1993, p. 328. 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Veterinary Parasitology  vol: 338  first page: 110529  year: 2025  
doi: 10.1016/j.vetpar.2025.110529

21. First report of multiple drug-resistant gastrointestinal nematodes of sheep in Arbat District, Sulaymaniyah, Iraq detected by in vivo and in vitro methods
Hiewa Othman Dyary, Hamasalih Qadir Banaz
Journal of Veterinary Research  vol: 65  issue: 3  first page: 293  year: 2021  
doi: 10.2478/jvetres-2021-0047

22. Influence of the physiological stage of Blackbelly sheep on immunological behaviour against gastrointestinal nematodes
R. González-Garduño, P. Mendoza-de Gives, M.E. López-Arellano, L. Aguilar-Marcelino, G. Torres-Hernández, N.F. Ojeda-Robertos, J.F.J. Torres-Acosta
Experimental Parasitology  vol: 193  first page: 20  year: 2018  
doi: 10.1016/j.exppara.2018.08.003

23. Comparative Evaluation of Two In Vitro Tests for Detection of Ivermectin Resistance in Haemonchus contortus of Small Ruminants in Uttar Pradesh, India
Ekta Singh, Dinesh Chandra, Arvind Prasad, Navneet Kaur
Acta Parasitologica  vol: 66  issue: 4  first page: 1565  year: 2021  
doi: 10.1007/s11686-021-00398-0

24. Investigation of productivity in a south Indian Malabari goat herd shows opportunities for planned animal health management to improve food security
N. D. Sargison, S. A. J. Ivil, J. Abraham, S. P. S. Abubaker, A. M. Hopker, S. Mazeri, I. A. Otter, N. Otter
Veterinary Record  vol: 180  issue: 11  first page: 278  year: 2017  
doi: 10.1136/vr.103801

25. Gastrointestinal nematode parasites of grazing ruminants: a comprehensive literature review of diagnostic methods for quantifying parasitism, larval differentiation and measuring anthelmintic resistance
MC Playford, RB Besier
New Zealand Veterinary Journal  vol: 73  issue: 3  first page: 149  year: 2025  
doi: 10.1080/00480169.2024.2415029

26. Effect of commercial tannins on parasitic infection and immunity of lambs naturally infected with Haemonchus contortus
Jesséa de Fátima França Biz, Sthefany Kamile dos Santos, Jordana Andrioli Salgado, Gervásio Henrique Bechara, Cristina Santos Sotomaior
Veterinary Parasitology: Regional Studies and Reports  vol: 38  first page: 100833  year: 2023  
doi: 10.1016/j.vprsr.2023.100833

27. Explaining variability in first grazing season heifer growth combining individually measured parasitological and clinical indicators with exposure to gastrointestinal nematode infection based on grazing management practice
Aurélie Merlin, Alain Chauvin, Aurélien Madouasse, Sébastien Froger, Nathalie Bareille, Christophe Chartier
Veterinary Parasitology  vol: 225  first page: 61  year: 2016  
doi: 10.1016/j.vetpar.2016.05.006

28. Cross-transmission of resistant gastrointestinal nematodes between wildlife and transhumant sheep
Camille Beaumelle, Carole Toïgo, Rodolphe Papet, Slimania Benabed, Mathieu Beurier, Léa Bordes, Anaïs Brignone, Nadine Curt-Grand-Gaudin, Mathieu Garel, Justine Ginot, Philippe Jacquiet, Christian Miquel, Marie-Thérèse Poirel, Anna Serafino, Eric Vannard, Gilles Bourgoin, Glenn Yannic
Peer Community Journal  vol: 4  year: 2024  
doi: 10.24072/pcjournal.477

29. Hematological changes in anemic dairy calves treated with a hematinic complex
Roberto González-Garduño, Fleider Leiser Peña-Escalona, Rocío Hernández-Díaz, Carlos Luna-Palomera, Ema de Jesús Maldonado-Siman, Ever del Jesus Flores-Santiago, Alfonso J Chay-Canul
Veterinary World  first page: 994  year: 2025  
doi: 10.14202/vetworld.2025.994-1001

30. Gastrointestinal nematode egg counts throughout the reproductive cycle of breeding ewes: Relation to body condition, FAMACHA© and dag scores
Marta González-Warleta, José Antonio Castro-Hermida, Mercedes Mezo
Veterinary Parasitology  vol: 340  first page: 110612  year: 2025  
doi: 10.1016/j.vetpar.2025.110612

31. Anthelmintic resistance and prevalence of gastrointestinal nematodes infecting sheep in Limpopo Province, South Africa
Morutse Mphahlele, Ana M. Tsotetsi-Khambule, Rebone Moerane, Dennis M. Komape, Oriel M. M. Thekisoe
Veterinary World  vol: 14  issue: 2  first page: 302  year: 2021  
doi: 10.14202/vetworld.2021.302-313

32. Nematode control in spring-born suckler beef calves using targeted selective anthelmintic treatments
J. O'Shaughnessy, B. Earley, J.F. Mee, M.L. Doherty, P. Crosson, D. Barrett, M. Macrelli, T. de Waal
Veterinary Parasitology  vol: 205  issue: 1-2  first page: 150  year: 2014  
doi: 10.1016/j.vetpar.2014.07.009

33. Multiple anthelmintic resistance at a goat farm in Slovakia
M. Babják, A. Königová, M. Várady
Helminthologia  vol: 58  issue: 2  first page: 173  year: 2021  
doi: 10.2478/helm-2021-0014

34. Survival of Nematode Larvae after Treatment with Eugenol, Isoeugenol, Thymol, and Carvacrol
Olexandra Boyko, Viktor Brygadyrenko
Frontiers in Bioscience-Elite  vol: 15  issue: 4  year: 2023  
doi: 10.31083/j.fbe1504025

35. In vitro anthelmintic activity of the crude hydroalcoholic extract of Piper cubeba fruits and isolated natural products against gastrointestinal nematodes in sheep
Matheus Souza de Paula Carlis, Aline Féboli, Antonio Carlos de Laurentiz, Rosemeire da Silva Filardi, Anna Helena Prizantelli de Oliveira, Márcio Luis Andrade e Silva, Luciano Alves dos Anjos, Lizandra Guidi Magalhães, Rosangela da Silva de Laurentiz
Veterinary Parasitology  vol: 275  first page: 108932  year: 2019  
doi: 10.1016/j.vetpar.2019.108932

36. Moisture but not temperature manipulations influence abundance of the free-living larvae of a parasitic nematode infecting Svalbard reindeer
T. M. Moerman, R. Wetherbee, M. Renčo, A. Stien, S. J. Coulson, L. E. Loe
Polar Biology  vol: 49  issue: 1  year: 2026  
doi: 10.1007/s00300-026-03451-8

37. Assessment of anthelmintic efficacy against cattle gastrointestinal nematodes in western France and southern Italy
C. Chartier, N. Ravinet, A. Bosco, E. Dufourd, M. Gadanho, A. Chauvin, J. Charlier, M.P. Maurelli, G. Cringoli, L. Rinaldi
Journal of Helminthology  vol: 94  year: 2020  
doi: 10.1017/S0022149X20000085

38. Efecto in vitro de los extractos hidroalcohólico y etanólico de semilla de papaya (Carica papaya) en Haemonchus contortus
María de los Ángeles Marroquín-Tun, Rosa Isabel Higuera-Piedrahita, María Eugenia López-Arellano, Raquel López-Arellano, Héctor Alejandro De la Cruz-Cruz, Rocío Silva-Mendoza, Jorge Alfredo Cuéllar-Ordaz
Ciencia y Agricultura  vol: 15  issue: 1  first page: 53  year: 2018  
doi: 10.19053/01228420.v15.n1.2018.7756

39. Rapid, automated quantification of Haemonchus contortus ova in sheep faecal samples
Jennifer L. Cain, Leonor Sicalo Gianechini, Abigail L. Vetter, Sarah M. Davis, Leah N. Britton, Jennifer L. Myka, Paul Slusarewicz
International Journal for Parasitology  vol: 54  issue: 1  first page: 47  year: 2024  
doi: 10.1016/j.ijpara.2023.07.003

40. Parasitological status of vicuñas (Vicugna vicugna) from southeastern Peru and its relationship with fiber quality
Carmen Arias-Pacheco, Danilo Pezo, Luis Antonio Mathias, José Hairton Tebaldi, Henry Castelo-Oviedo, Estevam G. Lux-Hoppe
Tropical Animal Health and Production  vol: 53  issue: 2  year: 2021  
doi: 10.1007/s11250-021-02650-1

41. Effect of green tea dust as a dietary additive and anthelminthic on performance, digestibility, and fecal egg counts in Priangan ewe lambs infected with Strongyles worms
Diky. Ramdani, Aldyansah Putra. Utama, Ririn Siti. Rahmatillah, Juju. Julaeha, Novi. Mayasari, Ken Ratu Gharizah. Alhuur, Nanik. Hidayatik, Anuraga. Jayanegara
Veterinary and Animal Science  vol: 26  first page: 100395  year: 2024  
doi: 10.1016/j.vas.2024.100395

42. Prevalence and severity of gastro-intestinal parasites in buffalo calves at Sylhet division of Bangladesh
Iffat Ara, Juned Ahmed, Prantho Malakar Dipta, Shampa Deb Nath, Taslima Akter, Mahfuz Rahman Adnan, Bishojit Deb, Shahrul Alam, Q. M. Monzur Kader Chowdhury, Asmaul Husna, Md. Mahfujur Rahman, Md. Masudur Rahman
Journal of Parasitic Diseases  vol: 45  issue: 3  first page: 620  year: 2021  
doi: 10.1007/s12639-020-01339-w

43. Characterisation of ivermectin and multi-drug resistance in two field isolates of Teladorsagia circumcincta from Irish sheep flocks
Jason D. Keegan, Orla M. Keane, Louise Farrell, William Byrne, Theo De Waal, Barbara Good
Veterinary Parasitology: Regional Studies and Reports  vol: 1-2  first page: 3  year: 2015  
doi: 10.1016/j.vprsr.2016.03.005

44. A national survey of the gastrointestinal nematode control practices used by goat producers in the United States
Ryan H. Avery, Natalie J. Urie, Matthew A. Branan, Alyson M. Wiedenheft, Elliott Dennis, Katherine L. Marshall, Joan M. Burke, James E. Miller
Veterinary Parasitology  vol: 334  first page: 110375  year: 2025  
doi: 10.1016/j.vetpar.2024.110375

45. Cattle gastrointestinal nematode egg-spiked faecal samples: high recovery rates using the Mini-FLOTAC technique
Alessandra Amadesi, Antonio Bosco, Laura Rinaldi, Giuseppe Cringoli, Edwin Claerebout, Maria Paola Maurelli
Parasites & Vectors  vol: 13  issue: 1  year: 2020  
doi: 10.1186/s13071-020-04107-0

46. Diagnosis of anthelmintic resistance in cattle in Brazil: A comparison of different methodologies
José Henrique das Neves, Nadino Carvalho, Laura Rinaldi, Giuseppe Cringoli, Alessandro F.T. Amarante
Veterinary Parasitology  vol: 206  issue: 3-4  first page: 216  year: 2014  
doi: 10.1016/j.vetpar.2014.10.015

47. Ivermectin treatment failure on four Irish dairy farms
James O’Shaughnessy, Yvonne Drought, John Lynch, Marian Denny, Christine Hurley, William Byrne, Mícheál Casey, Theo de Waal, Maresa Sheehan
Irish Veterinary Journal  vol: 72  issue: 1  year: 2019  
doi: 10.1186/s13620-019-0142-8

48. Wild ruminants as a potential risk factor for transmission of drug resistance in the abomasal nematode Haemonchus contortus
Štefánia Laca Megyesi, Alžbeta Königová, Michal Babják, Ladislav Molnár, Matúš Rajský, Edina Szestáková, Peter Major, Jaroslav Soroka, Michaela Urda Dolinská, Michaela Komáromyová, Marián Várady
European Journal of Wildlife Research  vol: 66  issue: 1  year: 2020  
doi: 10.1007/s10344-019-1351-x

49. Development of a lateral-flow assay for rapid detection of parasitic nematodes
Christopher Sander, Stephan Neumann
IJID One Health  vol: 5  first page: 100040  year: 2024  
doi: 10.1016/j.ijidoh.2024.100040

50. Molecular survey of trichostrongyle nematodes in a Bison bison herd experiencing clinical parasitism, and effects of avermectin treatment
A.A. Eljaki, Y.M. Al Kappany, D.D. Grosz, A.J. Smart, M.B. Hildreth
Veterinary Parasitology  vol: 227  first page: 48  year: 2016  
doi: 10.1016/j.vetpar.2016.07.022

51. Tree leaves of Salix babylonica extract as a natural anthelmintic for small-ruminant farms in a semiarid region in Mexico
Abdelfattah Z. M. Salem, Mona M. Y. Elghandour, Ahmed E. Kholif, Secundino López, Alberto B. Pliego, Moisés Cipriano-Salazar, Juan Carlos V. Chagoyán, Roberto Montes de Oca Jiménez, María U. Alonso
Agroforestry Systems  vol: 91  issue: 1  first page: 111  year: 2017  
doi: 10.1007/s10457-016-9909-z

52. Comparative growth performance of backgrounded beef heifers treated with an injectable fixed-dose combination (0.2 mg/kg doramectin + 6.0 mg/kg levamisole hydrochloride) or single-active (0.2 mg/kg ivermectin) endectocide
Andrew A. DeRosa, Susan Holzmer, Jase J. Ball, Landon P. Watkins, Mitchell Blanding, Mark Alley, Thomas H. Short, David T. Bechtol, Audie R. Waite, Elizabeth J. Rigoni, Jezaniah K. Tena
Veterinary Parasitology  vol: 323  first page: 110054  year: 2023  
doi: 10.1016/j.vetpar.2023.110054

53. Multi-infection parasitic nematodes in deer at Waru Farm Land, Ciampea, Bogor Regency
Ridi Arif, Trianita Damayanti, Sri Kusmiati
ARSHI Veterinary Letters  vol: 8  issue: 1  first page: 5  year: 2024  
doi: 10.29244/avl.8.1.5-6

54. Haemonchus contortus Parasitism in Intensively Managed Cross-Limousin Beef Calves: Effects on Feed Conversion and Carcass Characteristics and Potential Associations with Climatic Conditions
Konstantinos V. Arsenopoulos, Eleni I. Katsarou, Jairo A. Mendoza Roldan, George C. Fthenakis, Elias Papadopoulos
Pathogens  vol: 11  issue: 9  first page: 955  year: 2022  
doi: 10.3390/pathogens11090955

55. Emerging alternatives to traditional anthelmintics: the in vitro antiparasitic activity of silver and selenium nanoparticles, and pomegranate (Punica granatum) peel extract against Haemonchus contortus
Ahmed M. Kaiaty, Fayez A. Salib, Sohila M. El-Gameel, Emil S. Abdel Massieh, Ahmed M. Hussien, Mohamed S. Kamel
Tropical Animal Health and Production  vol: 55  issue: 5  year: 2023  
doi: 10.1007/s11250-023-03722-0

56. Copper chloride and copper sulphate in combination with nitroxynil against gastrointestinal nematodes of ruminants: A possible hitchhiking synergic effect at low concentrations
Carla Juliana Ribeiro Dolenga, Alan dos Anjos, Eduardo José Arruda, Marcelo Beltrão Molento
International Journal for Parasitology  vol: 53  issue: 3  first page: 177  year: 2023  
doi: 10.1016/j.ijpara.2022.12.003

57. Changes in biochemical analytes in calves infected by nematode parasites in field conditions
Marcela C. de Cezaro, Asta Tvarijonaviciute, Fernando Tecles, José J. Céron, David P. Eckersall, João C.P. Ferreira, Elizabeth M.S. Schmidt
Veterinary Parasitology  vol: 219  first page: 1  year: 2016  
doi: 10.1016/j.vetpar.2016.01.018

58. Multi-technology parasite detection: The intersection of tradition and innovation
ChenYu Wang, RuoFeng Xu, YuXiang Zeng, RuiNing He, Bo Zhang, YongKang Huang, ShuCheng Ma, YuXuan Zuo, YuJun Deng, YanYu Wang, Tao Xiong
Acta Tropica  vol: 267  first page: 107652  year: 2025  
doi: 10.1016/j.actatropica.2025.107652

59. Broad spectrum anthelmintic resistance of Haemonchus contortus in Northern NSW of Australia
Jane Lamb, Tim Elliott, Michael Chambers, Bruce Chick
Veterinary Parasitology  vol: 241  first page: 48  year: 2017  
doi: 10.1016/j.vetpar.2017.05.008

60. Parasitic infections in the organic beef cattle herds of southern Poland during the grazing season, with the first record of Calicophoron daubneyi (Dinnik, 1962) in the country
Paweł Nosal, Jerzy Kowal, Marta Basiaga, Andrzej Węglarz
Journal of Veterinary Research  vol: 69  issue: 1  first page: 59  year: 2025  
doi: 10.2478/jvetres-2025-0012

61. Anthelmintic activity of pomegranate peel extract (Punica granatum) and synthetic anthelmintics against gastrointestinal nematodes in cattle, sheep, goats, and buffalos: in vivo study
Ahmed M. Kaiaty, Fayez A. Salib, Sohila M. El-Gameel, Ahmed M. Hussien, Mohamed S. Kamel
Parasitology Research  vol: 120  issue: 11  first page: 3883  year: 2021  
doi: 10.1007/s00436-021-07311-8

62. Artificial Haemonchus contortus infection as a strategy to induce protective immune response to natural infection in Pelibuey lambs
A. Cruz-Tamayo, R. González-Garduño, G. Torres-Hernández, C. Becerril-Pérez, O. Hernández-Mendo, E. Ramírez-Bribiesca, M.E. López-Arellano, J. Vargas-Magaña, E. Hernández-Rueda
Journal of Helminthology  vol: 94  year: 2020  
doi: 10.1017/S0022149X20000656

63. High frequency of benzimidazole resistance alleles in trichostrongyloids from Austrian sheep flocks in an alpine transhumance management system
Barbara Hinney, Julia Schoiswohl, Lynsey Melville, Vahel J. Ameen, Walpurga Wille-Piazzai, Karl Bauer, Anja Joachim, Jürgen Krücken, Philip J. Skuce, Reinhild Krametter-Frötscher
BMC Veterinary Research  vol: 16  issue: 1  year: 2020  
doi: 10.1186/s12917-020-02353-z

64. Influence of sustained deworming pressure on the anthelmintic resistance status in strongyles of sheep under field conditions
M. K. Vijayasarathi, C. Sreekumar, R. Venkataramanan, M. Raman
Tropical Animal Health and Production  vol: 48  issue: 7  first page: 1455  year: 2016  
doi: 10.1007/s11250-016-1117-3

65. Hematological changes during pregnancy and lactation in Pelibuey ewes infected with gastrointestinal nematodes
Claudia Virginia Zaragoza-Vera, Roberto González-Garduño, Ever del Jesus Flores-Santiago, Alfonso Juventino Chay-Canul, Maritza Zaragoza-Vera, Guadalupe Arjona-Jiménez, Oswaldo Margarito Torres-Chablé
Comparative Clinical Pathology  vol: 31  issue: 5  first page: 827  year: 2022  
doi: 10.1007/s00580-022-03386-6

66. Study on Gastrointestinal Parasitism of Wild Animals in Captivity at the Zoological Garden of Haramaya University, Ethiopia
Dakalo Dashe, Amare Berhanu
Open Journal of Veterinary Medicine  vol: 10  issue: 09  first page: 173  year: 2020  
doi: 10.4236/ojvm.2020.109015

67. First report of anthelmintic resistance among sheep in six farms from three governorates in Jordan
Rami M. Mukbel, Abdelqader A. Kreishan, Haifa B. Hammad, Mohammad N.S. Al-Sabi
Veterinary Parasitology: Regional Studies and Reports  vol: 57  first page: 101171  year: 2025  
doi: 10.1016/j.vprsr.2024.101171

68. Inhibitory effect of dimethyl sulfoxide on the development of gastrointestinal nematode larvae in the larval development test
Marcin Mickiewicz, Zofia Nowek, Michał Czopowicz, Agata Moroz-Fik, Adrian-Valentin Potărniche, Kinga Biernacka, Olga Szaluś-Jordanow, Paweł Górski, Alistair Antonopoulos, Iwona Markowska-Daniel, Marián Várady, Jarosław Kaba
Journal of Veterinary Research  vol: 69  issue: 1  first page: 83  year: 2025  
doi: 10.2478/jvetres-2025-0016

69. Carvacryl acetate nanoencapsulated with chitosan/chichá gum exhibits reduced toxicity in mice and decreases the fecal egg count of sheep infected with gastrointestinal nematodes
Weibson P. P. André, José R. P. Junior, Géssica S. Cavalcante, Wesley L. C. Ribeiro, José V. Araújo-Filho, Selene M. Morais, Lorena M. B. Oliveira, Flávia O. M. S. Abreu, Claudia M. L. Bevilaqua
Parasitology  vol: 148  issue: 13  first page: 1560  year: 2021  
doi: 10.1017/S0031182021001220

70. Identification of third stage larval types of cyathostomins of equids: An improved perspective
Daisy Woellner Santos, Luis Manuel Madeira de Carvalho, Marcelo Beltrão Molento
Veterinary Parasitology  vol: 260  first page: 49  year: 2018  
doi: 10.1016/j.vetpar.2018.08.007

71. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.): Third edition of the guideline for evaluating efficacy of anthelmintics in ruminants (bovine, ovine, caprine)
D.J. Burden, D.J. Bartley, R.B. Besier, E. Claerebout, T.P. Elliott, J. Höglund, S. Rehbein, J.F.J. Torres-Acosta, J.A. Van Wyk, T. Yazwinski
Veterinary Parasitology  vol: 329  first page: 110187  year: 2024  
doi: 10.1016/j.vetpar.2024.110187

72. Haemonchosis: dealing with the increasing threat of the barber's pole worm
James Patrick Crilly, Mike Evans, Katrin Tähepõld, Neil Sargison
Livestock  vol: 25  issue: 5  first page: 237  year: 2020  
doi: 10.12968/live.2020.25.5.237

73. Essential oils fromOcimum basilicumcultivars: analysis of their composition and determination of the effect of the major compounds onHaemonchus contortuseggs
A.I.P. Sousa, C.R. Silva, H.N. Costa-Júnior, N.C.S. Silva, J.A.O. Pinto, A.F. Blank, A.M.S. Soares, L.M. Costa-Júnior
Journal of Helminthology  vol: 95  year: 2021  
doi: 10.1017/S0022149X21000080

74. Combination of immunostimulants with moxidectin in the treatment of animals experimentally infected with Haemonchus contortus
Luiza Pires Portella, Fagner D'ambroso Fernandes, Luís Antônio Sangioni, Fernanda Ramos, Fernando de Souza Rodrigues, Fernanda Rezer de Menezes, Alfredo Skrebsky Cezar, Tatiane Cargnin Faccin, Glaucia Denise Kommers, Fernanda Silveira Flores Vogel
Semina: Ciências Agrárias  vol: 42  issue: 2  first page: 707  year: 2021  
doi: 10.5433/1679-0359.2021v42n2p707

75. High frequency of benzimidazole resistance polymorphisms and age-class differences in trichostrongyle nematodes of ranched bison from the south-central United States
Kaylee R. Kipp, Elizabeth M. Redman, Joe L. Luksovsky, Dani Claussen, John S. Gilleard, Guilherme G. Verocai
International Journal for Parasitology: Drugs and Drug Resistance  vol: 28  first page: 100594  year: 2025  
doi: 10.1016/j.ijpddr.2025.100594

76. Efficacy of single and double doses of pour-on eprinomectin on small ruminant farms – Is it affected by Haemonchus contortus?
Michal Babják, Alžbeta Königová, Tetiana A. Kuzmina, Marián Várady
Veterinary Parasitology: Regional Studies and Reports  vol: 70  first page: 101471  year: 2026  
doi: 10.1016/j.vprsr.2026.101471

77. Anthelmintic resistance in goat herds—In vivo versus in vitro detection methods
M. Babják, A. Königová, M. Urda Dolinská, J. Vadlejch, M. Várady
Veterinary Parasitology  vol: 254  first page: 10  year: 2018  
doi: 10.1016/j.vetpar.2018.02.036

78. Formulating fungal spores to prevent infection by trichostrongylids in a zoological park: Practical approaches to a persisting problem
Antonio M. Palomero, Cristiana F. Cazapal-Monteiro, Cándido Viña, José Á. Hernández, Mathilde Voinot, María Vilá, María I. Silva, Adolfo Paz-Silva, Rita Sánchez-Andrade, María Sol Arias
Biological Control  vol: 152  first page: 104466  year: 2021  
doi: 10.1016/j.biocontrol.2020.104466

79. Exploring the Gastrointestinal “Nemabiome”: Deep Amplicon Sequencing to Quantify the Species Composition of Parasitic Nematode Communities
Russell W. Avramenko, Elizabeth M. Redman, Roy Lewis, Thomas A. Yazwinski, James D. Wasmuth, John S. Gilleard, Emmanuel Serrano Ferron
PLOS ONE  vol: 10  issue: 12  first page: e0143559  year: 2015  
doi: 10.1371/journal.pone.0143559

80. The use of high resolution melting analysis of ITS-1 for rapid differentiation of parasitic nematodes Haemonchus contortus and Ashworthius sidemi
Lucie Skorpikova, Nikol Reslova, Jan Magdalek, Jaroslav Vadlejch, Martin Kasny
Scientific Reports  vol: 10  issue: 1  year: 2020  
doi: 10.1038/s41598-020-73037-9

81. Epidemiological study of goat’s gastrointestinal nematodes in the North West of Algeria
Mokhtar Saidi, Michael J. Stear, Abdelkader Elouissi, Slimane Mokrani, Lakhder Belabid
Tropical Animal Health and Production  vol: 52  issue: 4  first page: 1787  year: 2020  
doi: 10.1007/s11250-019-02193-6

82. Anthelmintic Drug Resistance of Gastrointestinal Nematodes of Naturally Infected Goats in Haramaya, Ethiopia
Anteneh Wondimu, Yehualashet Bayu, María Eugenia López-Arellano
Journal of Parasitology Research  vol: 2022  first page: 1  year: 2022  
doi: 10.1155/2022/4025902

83. Optimum timing for assessing phenotypic resistance against gastrointestinal nematodes in Pelibuey ewes
C. V. Zaragoza-Vera, R. Gonzalez-Garduño, G. Arjona-Jimenez, M. Zaragoza-Vera, A. J. Aguilar-Caballero, O. M. Torres-Chable
Helminthologia  vol: 60  issue: 4  first page: 348  year: 2023  
doi: 10.2478/helm-2023-0038

84. Detection of anthelmintic resistance on two Irish beef research farms
J. O'Shaughnessy, B. Earley, J. F. Mee, M. L. Doherty, P. Crosson, D. Barrett, R. Prendiville, M. Macrelli, T. de Waal
Veterinary Record  vol: 175  issue: 5  first page: 120  year: 2014  
doi: 10.1136/vr.102556

85. Molecular detection of Cooperia oncophora and Ostertagia ostertagi in cattle: Comparison of sample processing and detection on ddPCR and qPCR platforms
Ian David Woolsey, Tonje Opsal, Lucy Robertson, Sokratis Ptochos, Lisbeth Hektoen
Experimental Parasitology  vol: 268  first page: 108878  year: 2025  
doi: 10.1016/j.exppara.2024.108878

86. Nematodes fauna of the genus Nematodirus (Nematoda) in domestic and semi-free-ranging ruminants of Central Uzbekistan
F. Akramova, U. Shakarbaev, A. Mirzaeva, S. Saidova, F. Uralova, O. Amirov, D. Azimov
Biosystems Diversity  vol: 33  issue: 4  first page: e2552  year: 2025  
doi: 10.15421/012552

87. Evaluation of a combination of Citrus aurantium var. Dulcis essential oil and albendazole for the treatment of sheep gastrointestinal nematodes
Dauana Mesquita-Sousa, Nagilla R.C.L. Campos, Juliana R.F. Pereira, Matheus N. Gomes, Carolina R. Silva, Jose A.A. Cutrim-Júnior, Danilo R.B. Brito, Romildo M. Sampaio, Neil D. Sargison, Adrian Lifschitz, Livio M. Costa-Junior
Veterinary Parasitology  vol: 318  first page: 109929  year: 2023  
doi: 10.1016/j.vetpar.2023.109929

88. Amostragem de prevalência de verminoses gastrointestinais em caprinos e ovinos na região central de Rondônia
Luan Felhipe dos Santos, Mateus Aparecido Clemente
Research, Society and Development  vol: 14  issue: 11  first page: e180141150145  year: 2025  
doi: 10.33448/rsd-v14i11.50145

89. Epidemiology and risk factors for endoparasite infection in subtropical feral cattle in Hong Kong
Tania A. Perroux, Samantha S.Y. Lie, Alan G. McElligott, Danchen A. Yang, Fraser I. Hill, George M.W. Hodgson, Wing S. Wong, Kate J. Flay
International Journal for Parasitology: Parasites and Wildlife  vol: 27  first page: 101082  year: 2025  
doi: 10.1016/j.ijppaw.2025.101082

90. Increase in anthelmintic resistance in sheep flocks in Ireland
Kyra M. Hamilton, Padraig O’Boyle, Amanda McEvoy, Dave M. Leathwick, Theo de Waal, Francis Campion, Orla M. Keane
Irish Veterinary Journal  vol: 79  issue: 1  year: 2026  
doi: 10.1186/s13620-025-00317-z

91. Seasonal dynamics of endoparasitic infections at an organic goat farm and the impact of detected infections on milk production
Iveta A. Kyriánová, Jaroslav Vadlejch, Oldřich Kopecký, Iva Langrová
Parasitology Research  vol: 116  issue: 11  first page: 3211  year: 2017  
doi: 10.1007/s00436-017-5643-3

92. Linalyl acetate against larvae of Haemonchus spp. and Trichostrongylus spp. that affects ruminants: considerations about the hormetic effect
V.P. Garbin, U.Y. Yoshitani, M.B. Molento
Journal of Helminthology  vol: 98  year: 2024  
doi: 10.1017/S0022149X24000488

93. Repurposing Ebselen for a potential blending-based therapeutic strategy against gastrointestinal nematodes of small ruminants
Irineu Romero-Neto, Júlia Dall'Anese, Taynara Gabriele Ribeiro Piano, Verônica Wosniaki Ferreira, Alda Lúcia Gomes Monteiro, Leandro Piovan, Marcelo Beltrão Molento
Research in Veterinary Science  vol: 198  first page: 105980  year: 2026  
doi: 10.1016/j.rvsc.2025.105980

94. Prevalence and risk factors associated with gastrointestinal nematode infection in goats raised in Baybay city, Leyte, Philippines
Ariel Paul M. Rupa, Harvie P. Portugaliza
Veterinary World  vol: 9  issue: 7  first page: 728  year: 2016  
doi: 10.14202/vetworld.2016.728-734

95. In vitro and in vivo anthelmintic properties of Caesalpinia coriaria fruits against Haemonchus contortus
César García-Hernández, Rolando Rojo-Rubio, Pedro Mendoza-de Gives, Manasés González-Cortazar, Alejandro Zamilpa, Jaime Mondragón-Ancelmo, Abel Villa-Mancera, Jaime Olivares-Pérez, Daniel Tapia-Maruri, Agustín Olmedo-Juárez
Experimental Parasitology  vol: 242  first page: 108401  year: 2022  
doi: 10.1016/j.exppara.2022.108401

96. Using Duddingtonia flagrans in calves under an organic milk farm production system in the Mexican tropics
Diego Otoniel Ortiz Pérez, Bernardo Sánchez Muñoz, José Nahed Toral, Miguel Ángel Orantes Zebadúa, José Luis Cruz López, María Eréndira Reyes García, Pedro Mendoza de Gives
Experimental Parasitology  vol: 175  first page: 74  year: 2017  
doi: 10.1016/j.exppara.2017.02.009

97. Nemabiome metabarcoding reveals differences between gastrointestinal nematode species infecting co-grazed sheep and goats
Livio M. Costa-Junior, Umer N. Chaudhry, Carolina R. Silva, Dauana M. Sousa, Naylene C. Silva, Jose A.A. Cutrim-Júnior, Danilo R.B. Brito, Neil D. Sargison
Veterinary Parasitology  vol: 289  first page: 109339  year: 2021  
doi: 10.1016/j.vetpar.2020.109339

98. Adaptations and phenotypic plasticity in developmental traits of Marshallagia marshalli
O. Alejandro Aleuy, Eric P. Hoberg, Chelsey Paquette, Kathreen E. Ruckstuhl, Susan Kutz
International Journal for Parasitology  vol: 49  issue: 10  first page: 789  year: 2019  
doi: 10.1016/j.ijpara.2019.05.007

99. Practical guide to the diagnostics of ruminant gastrointestinal nematodes, liver fluke and lungworm infection: interpretation and usability of results
Gustavo Adolfo Sabatini, Fernando de Almeida Borges, Edwin Claerebout, Leonor Sicalo Gianechini, Johan Höglund, Ray Matthew Kaplan, Welber Daniel Zanetti Lopes, Sian Mitchell, Laura Rinaldi, Georg von Samson-Himmelstjerna, Pedro Steffan, Robert Woodgate
Parasites & Vectors  vol: 16  issue: 1  year: 2023  
doi: 10.1186/s13071-023-05680-w

100. Cytokine responses to various larval stages of equine strongyles and modulatory effects of the adjuvant G3 in vitro
Stina Hellman, Eva Tydén, Bernt Hjertner, Frida Nilsfors, Kefei Hu, Bror Morein, Caroline Fossum
Parasite Immunology  vol: 43  issue: 1  year: 2021  
doi: 10.1111/pim.12794

101. Ostertagia ostertagi antibodies in bulk tank milk from dairy cattle in Italy: A nation-wide survey
Antonio Bosco, Alessandra Amadesi, Nicola Morandi, Paola Pepe, Maria Paola Maurelli, Giuseppe Cringoli, Laura Rinaldi
Veterinary Parasitology: Regional Studies and Reports  vol: 13  first page: 166  year: 2018  
doi: 10.1016/j.vprsr.2018.06.002

102. The threat of reduced efficacy of anthelmintics against gastrointestinal nematodes in sheep from an area considered anthelmintic resistance-free
Antonio Bosco, Jan Kießler, Alessandra Amadesi, Marian Varady, Barbara Hinney, Davide Ianniello, Maria Paola Maurelli, Giuseppe Cringoli, Laura Rinaldi
Parasites & Vectors  vol: 13  issue: 1  year: 2020  
doi: 10.1186/s13071-020-04329-2

103. Nematicidal activity of essential oils of medicinal plants
Olexandra Boyko, Viktor Brygadyrenko
Folia Oecologica  vol: 48  issue: 1  first page: 42  year: 2021  
doi: 10.2478/foecol-2021-0005

104. Broad-Spectrum Inhibitors for Conserved Unique Phosphoethanolamine Methyltransferases in Parasitic Nematodes Possess Anthelmintic Efficacy
Xuejin Zhang, Leonor Sicalo Gianechini, Kun Li, Ray M. Kaplan, William H. Witola
Antimicrobial Agents and Chemotherapy  vol: 67  issue: 6  year: 2023  
doi: 10.1128/aac.00008-23

105. Factors affecting the prevalence of endoparasites in pre-weaning calves in a warm humid climate of Mexico
C. Y. León-González, R. González-Garduño, J. M. Hernández-Domínguez, F. L. Peña-Escalona, A. Villa-Mancera, L. Aguilar-Marcelino
Helminthologia  vol: 62  issue: 1  first page: 30  year: 2025  
doi: 10.2478/helm-2025-0003

106. Preliminary observations on the value of using effective anthelmintic drugs to control nematode parasitism in lambs in the face of a high level of infective larval challenge
V. Busin, N.D. Sargison
Small Ruminant Research  vol: 119  issue: 1-3  first page: 172  year: 2014  
doi: 10.1016/j.smallrumres.2014.02.001

107. Comparative genomics and phylogenomics of Trichostrongyloidea mitochondria reveal insights for molecular diagnosis and evolutionary biology of nematode worms
Livia Loiola dos Santos, Francisco Prosdocimi, Nicholas Costa Barroso Lima, Igor Rodrigues da Costa, Danielle Cunha Cardoso, Marcela Gonçalves Drummond, Bruno dos Santos Alves Figueiredo Brasil, Eduardo Bastianetto, Denise Aparecida Andrade de Oliveira
Gene Reports  vol: 9  first page: 65  year: 2017  
doi: 10.1016/j.genrep.2017.09.002

108. Validation of targeted selective treatment (TST) methodology for gastrointestinal parasites of adult sheep in different physiological states
Matheus Borges de Carvalho, Diógenes Adriano Duarte Santana, Caroline Ramos dos Santos, Saulo Henrique Weber, Deborah Ribeiro Carvalho, Cristina Santos Sotomaior
Veterinary Parasitology  vol: 323  first page: 110022  year: 2023  
doi: 10.1016/j.vetpar.2023.110022

109. Relationships among body condition score, FAMACHA© score and haematological parameters in Pelibuey ewes
Oswaldo Margarito Torres-Chable, Ricardo Alfonso García-Herrera, Roberto González-Garduño, Nadia Florencia Ojeda-Robertos, Jorge Alonso Peralta-Torres, Alfonso Juventino Chay-Canul
Tropical Animal Health and Production  vol: 52  issue: 6  first page: 3403  year: 2020  
doi: 10.1007/s11250-020-02373-9

110. Evaluation of new formulations of nematophagous fungi Duddingtonia flagrans to control gastrointestinal nematodes in post-weaning lambs in Colombia Andean region
Jaime Andrés Cubides-Cárdenas, Jimmy Jolman Vargas Duarte, Henry Grajales Lombana, Elizabeth Céspedes-Gutiérrez, Martha Isabel Gómez-Álvarez, Diego Francisco Cortés-Rojas
Small Ruminant Research  vol: 223  first page: 106980  year: 2023  
doi: 10.1016/j.smallrumres.2023.106980

111. Gastrointestinal nematode infections do not hinder the development of Simmental X Nellore crossbred calves raised with a nutritionally enhanced diet
José Henrique das Neves, Nadino Carvalho, Alessandro Francisco Talamini do Amarante
Revista Brasileira de Parasitologia Veterinária  vol: 29  issue: 1  year: 2020  
doi: 10.1590/s1984-29612020006

112. A molecular assessment of Ostertagia leptospicularis and Spiculopteragia asymmetrica among wild fallow deer in Northern Ireland and implications for false detection of livestock-associated species
Maggie Lyons, Tony L. Brown, Angela Lahuerta-Marin, Eric. R. Morgan, Paul M. Airs
Parasites & Vectors  vol: 17  issue: 1  year: 2024  
doi: 10.1186/s13071-024-06147-2

113. History and development of research on wildlife parasites in southern Africa, with emphasis on terrestrial mammals, especially ungulates
Kerstin Junker, Ivan G. Horak, Banie Penzhorn
International Journal for Parasitology: Parasites and Wildlife  vol: 4  issue: 1  first page: 50  year: 2015  
doi: 10.1016/j.ijppaw.2014.12.003

114. The effects of triclabendazole, combined tetramisole with Oxyclozanide, and albendazole against ovine fasciolosis
Tameru Gedefaw, Atsede Solomon Mebratu, Shimels Dagnachew, Melkie Dagnaw Fenta
Scientific Reports  vol: 15  issue: 1  year: 2025  
doi: 10.1038/s41598-025-90015-1

115. Sustainability of pasture ecosystems: The use of plant-based mixtures in the fight against helminths
O. O. Boyko, V. V. Brygadyrenko
Biosystems Diversity  vol: 33  issue: 2  first page: e2532  year: 2025  
doi: 10.15421/012532

116. Nematophagous fungi as biological control agents of parasitic nematodes in soils of wildlife parks
Christopher Sander, Stephan Neumann
International Journal for Parasitology: Parasites and Wildlife  vol: 26  first page: 101033  year: 2025  
doi: 10.1016/j.ijppaw.2024.101033

117. Rapid assessment of faecal egg count and faecal egg count reduction through composite sampling in cattle
Laura Rinaldi, Alessandra Amadesi, Elaudy Dufourd, Antonio Bosco, Marion Gadanho, Anne Lehebel, Maria Paola Maurelli, Alain Chauvin, Johannes Charlier, Giuseppe Cringoli, Nadine Ravinet, Christophe Chartier
Parasites & Vectors  vol: 12  issue: 1  year: 2019  
doi: 10.1186/s13071-019-3601-x

118. Cell grazing and Haemonchus contortus control in sheep: lessons from a two-year study in temperate Western Europe
C. Ruiz-Huidobro, L. Sagot, S. Lugagne, Y. Huang, M. Milhes, L. Bordes, F. Prévot, C. Grisez, D. Gautier, C. Valadier, M. Sautier, P. Jacquiet
Scientific Reports  vol: 9  issue: 1  year: 2019  
doi: 10.1038/s41598-019-49034-y

119. A real-time PCR approach to identify anthelmintic-resistant nematodes in sheep farms
M. Milhes, M. Guillerm, M. Robin, M. Eichstadt, C. Roy, C. Grisez, F. Prévot, E. Liénard, E. Bouhsira, M. Franc, P. Jacquiet
Parasitology Research  vol: 116  issue: 3  first page: 909  year: 2017  
doi: 10.1007/s00436-016-5364-z

120. Ramming the parasites: Evaluation of quarantine procedures against Haemonchus contortus at sheep markets in Sweden
Johan Höglund, Giulio Grandi, Nizar Enweji, Katarina Gustafsson
Veterinary Parasitology: Regional Studies and Reports  vol: 56  first page: 101125  year: 2024  
doi: 10.1016/j.vprsr.2024.101125

121. Gastrointestinal and pulmonary nematodes in calves naturally infected in the cities of Botucatu and Manduri, in the Brazilian state of São Paulo
Marcela C. Cezaro, José H. Neves, José R.L.M. Cury, Felipe M. Dalanezi, Raphaela M. Oliveira, João C.P. Ferreira, Vitoldo A.K. Neto, Elizabeth M.S. Schmidt
Pesquisa Veterinária Brasileira  vol: 38  issue: 7  first page: 1286  year: 2018  
doi: 10.1590/1678-5150-pvb-5225

122. Gastrointestinal Nematode Infections in Antelopes from Morocco: A Coprological Survey
Saidi Aissa, Mimouni Rachida, Hamadi Fatima, Oubrou Widade
Acta Veterinaria  vol: 71  issue: 1  first page: 47  year: 2021  
doi: 10.2478/acve-2021-0004

123. Assessing the individual and combined use of Caesalpinia coriaria (Plantae: Fabaceae) and Duddingtonia flagrans (Fungi: Orbiliaceae) as sustainable alternatives of control of sheep parasitic nematodes
Luzlady Chavarría-Joya, Miguel Ángel Alonso-Díaz, Agustín Olmedo-Juárez, Elke von Son-de Fernex, Pedro Mendoza-de-Gives
Biocontrol Science and Technology  vol: 32  issue: 11  first page: 1260  year: 2022  
doi: 10.1080/09583157.2021.2022600

124. Demonstration of reduced efficacy against cyathostomins without change in species composition after pyrantel embonate treatment in Swedish equine establishments
Ylva Hedberg Alm, Peter Halvarsson, Frida Martin, Eva Osterman-Lind, Vendela Törngren, Eva Tydén
International Journal for Parasitology: Drugs and Drug Resistance  vol: 23  first page: 78  year: 2023  
doi: 10.1016/j.ijpddr.2023.11.003

125. Anti-parasitic activity of pelleted sainfoin (Onobrychis viciifolia) against Ostertagia ostertagi and Cooperia oncophora in calves
Olivier Desrues, Miguel Peña-Espinoza, Tina V. A. Hansen, Heidi L. Enemark, Stig M. Thamsborg
Parasites & Vectors  vol: 9  issue: 1  year: 2016  
doi: 10.1186/s13071-016-1617-z

126. Study of gastrointestinal parasites in water buffalo (Bubalus bubalis) reared under Mexican humid tropical conditions
Nadia Florencia Ojeda-Robertos, Oswaldo Margarito Torres-Chablé, Jorge Alonso Peralta-Torres, Carlos Luna-Palomera, Aguilar Aguilar-Cabrales, Alfonso Juventino Chay-Canul, Roberto González-Garduño, Carlos Machain-Williams, Ramón Cámara-Sarmiento
Tropical Animal Health and Production  vol: 49  issue: 3  first page: 613  year: 2017  
doi: 10.1007/s11250-017-1237-4

127. Gastrointestinal helminth infections of dairy goats in Slovakia
M. Babják, A. Königová, M. Urda-Dolinská, M. Várady
Helminthologia  vol: 54  issue: 3  first page: 211  year: 2017  
doi: 10.1515/helm-2017-0027

128. Widespread resistance to macrocyclic lactones in cattle nematodes in Ecuador
Pamela Vinueza Veloz, Richar Rodriguez-Hidalgo, Maritza Celi-Erazo, Stijn Casaert, Peter Geldhof
Veterinary Parasitology: Regional Studies and Reports  vol: 23  first page: 100517  year: 2021  
doi: 10.1016/j.vprsr.2020.100517

129. Nemabiome metabarcoding shows a high prevalence of Haemonchus contortus and predominance of Camelostrongylus mentulatus in alpaca herds in the northern UK
Osama Zahid, Meghan Butler, Andy Hopker, Emily Freeman, Livio M. Costa Júnior, Umer Chaudhry, Neil Sargison
Parasitology Research  vol: 123  issue: 5  year: 2024  
doi: 10.1007/s00436-024-08226-w

130. High levels of third-stage larvae (L3) overwinter survival for multiple cattle gastrointestinal nematode species on western Canadian pastures as revealed by ITS2 rDNA metabarcoding
Tong Wang, Russell W. Avramenko, Elizabeth M. Redman, Janneke Wit, John S. Gilleard, Douglas D. Colwell
Parasites & Vectors  vol: 13  issue: 1  year: 2020  
doi: 10.1186/s13071-020-04337-2

131. Seasonal epidemiology of gastrointestinal nematodes of cattle in the northern continental climate zone of western Canada as revealed by internal transcribed spacer-2 ribosomal DNA nemabiome barcoding
Tong Wang, Elizabeth M. Redman, Arianna Morosetti, Rebecca Chen, Sarah Kulle, Natasha Morden, Christopher McFarland, Hannah Rose Vineer, Douglas D. Colwell, Eric R. Morgan, John S. Gilleard
Parasites & Vectors  vol: 14  issue: 1  year: 2021  
doi: 10.1186/s13071-021-05101-w

132. Prevalence and associated risk factors of gastrointestinal helminths and coccidian infections in domestic goats, Capra hircus, in Minya, Egypt
Hend Ibrahim Mohamed, Waleed M. Arafa, Khaled Mohamed El-Dakhly
Beni-Suef University Journal of Basic and Applied Sciences  vol: 12  issue: 1  year: 2023  
doi: 10.1186/s43088-023-00369-6

133. Comparison of ITS-2 rDNA nemabiome sequencing with morphological identification to quantify gastrointestinal nematode community species composition in small ruminant feces
Emma A. Borkowski, Elizabeth M. Redman, Rebecca Chant, Jacob Avula, Paula I. Menzies, Niel A. Karrow, Brandon N. Lillie, William Sears, John S. Gilleard, Andrew S. Peregrine
Veterinary Parasitology  vol: 282  first page: 109104  year: 2020  
doi: 10.1016/j.vetpar.2020.109104

134. Soil fungi enable the control of gastrointestinal nematodes in wild bovidae captive in a zoological park: a 4-year trial
A. M. Palomero, C. F. Cazapal-Monteiro, E. Valderrábano, A. Paz-Silva, R. Sánchez-Andrade, M. S. Arias
Parasitology  vol: 147  issue: 7  first page: 791  year: 2020  
doi: 10.1017/S0031182020000414

135. Anthelmintic activity of injectable eprinomectin (eprecis® 20 mg/mL) in naturally infected dairy sheep
Sofia-Afroditi Termatzidou, Konstantinos Arsenopoulos, Nektarios Siachos, Panagiota Kazana, Elias Papadopoulos, Damien Achard, Hamadi Karembe, Georgios Bramis, Georgios Arsenos
Veterinary Parasitology  vol: 266  first page: 7  year: 2019  
doi: 10.1016/j.vetpar.2018.12.014

136. Multidrug resistance in Haemonchus contortus in sheep - can it be overcome?
Michal Babják, Alžbeta Königová, Michaela Komáromyová, Tetiana Kuzmina, Pawel Nosal, Marián Várady
Journal of Veterinary Research  vol: 67  issue: 4  first page: 575  year: 2023  
doi: 10.2478/jvetres-2023-0057

137. A method for single pair mating in an obligate parasitic nematode
Neil D. Sargison, Elizabeth Redman, Alison A. Morrison, David J. Bartley, Frank Jackson, Hardeep Naghra-van Gijzel, Nancy Holroyd, Matthew Berriman, James A. Cotton, John S. Gilleard
International Journal for Parasitology  vol: 48  issue: 2  first page: 159  year: 2018  
doi: 10.1016/j.ijpara.2017.08.010

138. Effect of pomegranate (Punica granatum) anthelmintic treatment on milk production in dairy sheep naturally infected with gastrointestinal nematodes
Fabio Castagna, Roberto Bava, Ernesto Palma, Valeria Morittu, Antonella Spina, Carlotta Ceniti, Carmine Lupia, Giuseppe Cringoli, Laura Rinaldi, Antonio Bosco, Stefano Ruga, Domenico Britti, Vincenzo Musella
Frontiers in Veterinary Science  vol: 11  year: 2024  
doi: 10.3389/fvets.2024.1347151

139. Comparison of internal parasitic fauna in dairy goats at conventional and organic farms in the Czech Republic
I.A. Kyriánová, O. Kopecký, S. Šlosárková, J. Vadlejch
Small Ruminant Research  vol: 175  first page: 126  year: 2019  
doi: 10.1016/j.smallrumres.2019.05.003

140. Development and field evaluation of a species-specific mt-COI targeted SYBR-Green Real Time PCR for detection and quantification of Haemonchus contortus in cattle in Turkey
Onder Duzlu, Alparslan Yildirim, Gamze Yetismis, Zuhal Onder, Emrah Simsek, Arif Ciloglu, Gozde Sahingoz Demirpolat, Abdullah Inci
Veterinary Parasitology  vol: 277  first page: 109020  year: 2020  
doi: 10.1016/j.vetpar.2019.109020

141. Efficacy and persistent activity of moxidectin against natural Muellerius capillaris infection in goats and pathological consequences of muelleriosis
Jaroslav Vadlejch, Pavol Makovický, Zuzana Čadková, Iva Langrová
Veterinary Parasitology  vol: 218  first page: 98  year: 2016  
doi: 10.1016/j.vetpar.2016.01.009

142. Molecular diagnosis of benzimidazole resistance in Haemonchus contortus in sheep from different geographic regions of North India
S. Chandra, A. Prasad, M. Sankar, N. Yadav, S. Dalal
Veterinary World  vol: 7  issue: 5  first page: 337  year: 2014  
doi: 10.14202/vetworld.2014.337-341

143. Conjunctival mucous membrane colour as an indicator for the targeted selective treatment of haemonchosis and of the general health status of peri-urban smallholder goats in southern Malawi
N.D. Sargison, S. Mazeri, L. Gamble, F. Lohr, P. Chikungwa, J. Chulu, K.T. Hunsberger, N. Jourdan, A. Shah, J.L. Burdon Bailey
Preventive Veterinary Medicine  vol: 186  first page: 105225  year: 2021  
doi: 10.1016/j.prevetmed.2020.105225

144. Evaluation of Pelibuey Lambs Born to Mothers Phenotypically Segregated According to Resistance to Gastrointestinal Nematodes in the Humid Tropics of Mexico
Claudia Virginia Zaragoza-Vera, Roberto Gonzalez-Garduño, Maritza Zaragoza-Vera, Guadalupe Arjona-Jimenez, Antonio Ortega-Pacheco, Oswaldo Margarito Torres-Chable
Journal of Parasitology  vol: 109  issue: 1  year: 2023  
doi: 10.1645/22-44

145. Multispecific resistance of sheep trichostrongylids in Austria
Florian Untersweg, Viktoria Ferner, Sandra Wiedermann, Marie Göller, Marion Hörl-Rannegger, Waltraud Kaiser, Anja Joachim, Laura Rinaldi, Jürgen Krücken, Barbara Hinney
Parasite  vol: 28  first page: 50  year: 2021  
doi: 10.1051/parasite/2021048

146. Exploring animal enclosures and parasite interactions in Germany
Christopher Sander, Niko Balkenhol, Stephan Neumann
International Journal for Parasitology: Parasites and Wildlife  vol: 25  first page: 101009  year: 2024  
doi: 10.1016/j.ijppaw.2024.101009

147. Comparison of P-glycoprotein gene expression of two Haemonchus contortus isolates from Yucatan, Mexico, with resistant or susceptible phenotype to ivermectin in relation to a susceptible reference strain
Lisandro Alberto Encalada-Mena, Juan Felipe Torres-Acosta, Carlos Alfredo Sandoval-Castro, David E. Reyes-Guerrero, María Gabriela Mancilla-Montelongo, Raquel López-Arellano, Agustín Olmedo-Juárez, Ma. Eugenia López-Arellano
Veterinary Parasitology: Regional Studies and Reports  vol: 52  first page: 101047  year: 2024  
doi: 10.1016/j.vprsr.2024.101047

148. Multiple-resistance to ivermectin and benzimidazole of a Haemonchus contortus population in a sheep flock from mainland France, first report
T. Cazajous, F. Prevot, A. Kerbiriou, M. Milhes, C. Grisez, A. Tropee, C. Godart, A. Aragon, P. Jacquiet
Veterinary Parasitology: Regional Studies and Reports  vol: 14  first page: 103  year: 2018  
doi: 10.1016/j.vprsr.2018.09.005

149. Abomasal Nematodes of Goat and In Vitro Evaluation of Anthelmintic Resistance in Arba Minch Zuria District, South Ethiopia
Abreham Wondimu, Tamirat Kaba, Yemsrach Wubayehu, María Eugenia López-Arellano
Journal of Parasitology Research  vol: 2025  issue: 1  year: 2025  
doi: 10.1155/japr/9921528

150. Anthelmintic resistance to ivermectin and moxidectin in gastrointestinal nematodes of cattle in Europe
Thomas Geurden, Christophe Chartier, Jane Fanke, Antonio Frangipane di Regalbono, Donato Traversa, Georg von Samson-Himmelstjerna, Janina Demeler, Hima Bindu Vanimisetti, David J. Bartram, Matthew J. Denwood
International Journal for Parasitology: Drugs and Drug Resistance  vol: 5  issue: 3  first page: 163  year: 2015  
doi: 10.1016/j.ijpddr.2015.08.001

151. Portable near-infrared spectroscopy: A rapid and accurate blood test for diagnosis of Haemonchus contortus infection and for targeted selective treatment of sheep
Isabella B. Santos, Avelardo U.C. Ferreira, Márcio D. Rabelo, Luís Adriano Anholeto, Gustavo A. Sousa, Yousmel A. Gaínza, Amanda Figueiredo, Sérgio N. Esteves, Ana Carolina S. Chagas
International Journal for Parasitology  vol: 53  issue: 2  first page: 119  year: 2023  
doi: 10.1016/j.ijpara.2022.12.004

152. Faecal egg counts in Australian pasture-based dairy herds
T. Loughnan, P. Mansell, M. Playford, D. Beggs
Veterinary Parasitology: Regional Studies and Reports  vol: 51  first page: 101028  year: 2024  
doi: 10.1016/j.vprsr.2024.101028

153. Effect of tanniniferous food from Bauhinia pulchella on pasture contamination with gastrointestinal nematodes from goats
Suzana G. Lopes, Lilyan B. G. Barros, Helder Louvandini, Adibe L. Abdalla, Livio M. Costa Junior
Parasites & Vectors  vol: 9  issue: 1  year: 2016  
doi: 10.1186/s13071-016-1370-3

154. Effect of antihelminths with contrasting efficacy against gastrointestinal nematodes on the live-weight gain of young Nellore cattle
José Henrique das Neves, Nadino Carvalho, Nayara Capaldi dos Santos, João Ratti Júnior, Cyntia L. Martins, Alessandro F.T. Amarante
Veterinary Parasitology: Regional Studies and Reports  vol: 25  first page: 100597  year: 2021  
doi: 10.1016/j.vprsr.2021.100597

155. Genotyping of benzimidazole resistance using β-tubulin isotype 1 marker in Haemonchus contortus of sheep and goats in Paraná, Southern Brazil
C. Melchior do Prado, J. Ferreira Vasconcelos Rodrigues, G.A. Frota, D.L. Vieira, J.P. Monteiro, M. Beltrão Molento
Journal of Helminthology  vol: 98  year: 2024  
doi: 10.1017/S0022149X24000555

156. Anthelmintic resistance in gastrointestinal nematodes on communally reared sheep farms of the King Sabata Dalindyebo Municipality, South Africa
Songezo Mavundela, William Diymba Dzemo, Oriel Thekisoe
Parasitology Research  vol: 124  issue: 8  year: 2025  
doi: 10.1007/s00436-025-08532-x

157. Practical guide for microscopic identification of infectious gastrointestinal nematode larvae in sheep from Sardinia, Italy, backed by molecular analysis
Stephane Knoll, Giorgia Dessì, Claudia Tamponi, Luisa Meloni, Lia Cavallo, Naunain Mehmood, Philippe Jacquiet, Antonio Scala, Maria Grazia Cappai, Antonio Varcasia
Parasites & Vectors  vol: 14  issue: 1  year: 2021  
doi: 10.1186/s13071-021-05013-9

158. First Record of Molecular Confirmation, Phylogeny and Haplotype Diversity of Haemonchus contortus from Gaddi (breed) Goats of North India
Aman Dev Moudgil, Ankur Sharma, Pradeep Kumar Dogra
Brazilian Archives of Biology and Technology  vol: 65  year: 2022  
doi: 10.1590/1678-4324-2022210369

159. Implication of the fecal egg count reduction test (FECRT) in sheep for better use of available drugs
Jordana Andrioli Salgado, Letícia Vidal Cruz, Letícia Oliveira da Rocha, Cristina Santos Sotomaior, Tâmara Duarte Borges, Clóvis de Paula Santos
Revista Brasileira de Parasitologia Veterinária  vol: 28  issue: 4  first page: 700  year: 2019  
doi: 10.1590/s1984-29612019093

160. Multiple-species resistance to avermectin anthelmintics on beef cattle farms in Georgia, USA
Leonor Sicalo Gianchini, Kelsey L. Paras, Melissa M. George, Sue B. Howell, Bob Storey, Matthew J. Denwood, Ray M. Kaplan
Veterinary Parasitology  vol: 336  first page: 110435  year: 2025  
doi: 10.1016/j.vetpar.2025.110435

161. Variation in phenotypic resistance to gastrointestinal nematodes in hair sheep in the humid tropics of Mexico
Claudia V. Zaragoza-Vera, Armando J. Aguilar-Caballero, Roberto González-Garduño, Guadalupe Arjona-Jiménez, Maritza Zaragoza-Vera, Juan Felipe J. Torres-Acosta, José U. Medina-Reynés, Alma C. Berumen-Alatorre
Parasitology Research  vol: 118  issue: 2  first page: 567  year: 2019  
doi: 10.1007/s00436-018-06201-w

162. Antibacterial and nematicidal activities of extracts from plants of the Asteraceae family
V. V. Zazharskyi, V. V. Brygadyrenko, N. M. Zazharska, I. V. Borovik, O. O. Boyko, O. М. Kulishenko, P. О. Davydenko
Regulatory Mechanisms in Biosystems  vol: 15  issue: 3  first page: 587  year: 2024  
doi: 10.15421/022482

163. Comparative analysis of anthelmintic treatments: impact on liver biomarkers and clinical recovery in sheep with fasciolosis
Tameru Gedefaw, Atsede Solomon Mebratu, Shimels Dagnachew, Melkie Dagnaw Fenta
Frontiers in Veterinary Science  vol: 12  year: 2025  
doi: 10.3389/fvets.2025.1485568

164. Effect of essential oils on cattle gastrointestinal nematodes assessed by egg hatch, larval migration and mortality testing
S. Saha, S. Lachance
Journal of Helminthology  vol: 94  year: 2020  
doi: 10.1017/S0022149X19001081

165. Salivary, serum, and abomasal mucus IgA as an immune correlate of protection against Haemonchus contortus infection in naturally infected lambs
Jordana Andrioli Salgado, Sthefany Kamile dos Santos, Jesséa de Fátima França Biz, Matheus Borges de Carvalho, Fernanda Rigo, Breno Castello Branco Beirão, Alessandro Francisco Talamini do Amarante, Leandro Batista Costa, Cristina Santos Sotomaior
Research in Veterinary Science  vol: 144  first page: 82  year: 2022  
doi: 10.1016/j.rvsc.2022.01.006

166. Diagnostic Methods for Detecting Internal Parasites of Livestock
Guilherme G. Verocai, Umer N. Chaudhry, Manigandan Lejeune
Veterinary Clinics of North America: Food Animal Practice  vol: 36  issue: 1  first page: 125  year: 2020  
doi: 10.1016/j.cvfa.2019.12.003

167. Gastrointestinal parasitic infections in Indian Gaddi (goat) breed bucks: clinical, hemato-biochemical, parasitological and chemotherapeutic studies
Aman Dev Moudgil, Ankur Sharma, Madan Singh Verma, Ravindra Kumar, Pradeep Kumar Dogra, Pallavi Moudgil
Journal of Parasitic Diseases  vol: 41  issue: 4  first page: 1059  year: 2017  
doi: 10.1007/s12639-017-0934-2

168. Use of perennial plants in the fight against gastrointestinal nematodes of sheep
Antonio Bosco, Antonello Prigioniero, Alessandra Falzarano, Maria Paola Maurelli, Laura Rinaldi, Giuseppe Cringoli, Giovanni Quaranta, Salvatore Claps, Rosaria Sciarrillo, Carmine Guarino, Pierpaolo Scarano
Frontiers in Parasitology  vol: 2  year: 2023  
doi: 10.3389/fpara.2023.1186149

169. The impact of acids approved for use in foods on the vitality of Haemonchus contortus and Strongyloides papillosus (Nematoda) larvae
O. O. Boyko, V. V. Brygadyrenko
Helminthologia  vol: 56  issue: 3  first page: 202  year: 2019  
doi: 10.2478/helm-2019-0017

170. The in vitro exsheathment kinetics of Trichostrongylus colubriformis L3 in ruminal, abomasal, and two-stage incubation protocols
Dilcia Yobed Miranda-Miranda, Cindy Goretti Marin-Tun, Concepción Manuela Capetillo-Leal, María Gabriela Mancilla-Montelongo, Carlos Alfredo Sandoval-Castro, Juan Felipe de Jesús Torres-Acosta
Veterinary Parasitology  vol: 343  first page: 110715  year: 2026  
doi: 10.1016/j.vetpar.2026.110715

171. Effect of humic acid supplementation on lamb gastrointestinal health and performance
Diógenes Adriano Duarte Santana, Francieli Rolinski, Leticia Graziela Trombetta, Rafaela Maria Debastiani Göhringer, Tharini Xavier Accioly Kaled, Caroline Ramos dos Santos, Saulo Henrique Weber, Cristina Santos Sotomaior, Rüdiger Daniel Ollhoff
Tropical Animal Health and Production  vol: 58  issue: 2  year: 2026  
doi: 10.1007/s11250-026-04882-5

172. First report of monepantel Haemonchus contortus resistance on sheep farms in Uruguay
América E Mederos, Zully Ramos, Georgget E Banchero
Parasites & Vectors  vol: 7  issue: 1  year: 2014  
doi: 10.1186/s13071-014-0598-z

173. Anthelmintic activity of nanoencapsulated carvacryl acetate against gastrointestinal nematodes of sheep and its toxicity in rodents
Weibson Paz Pinheiro André, José Ribamar de Paiva Junior, Géssica Soares Cavalcante, Wesley Lyeverton Correia Ribeiro, José Vilemar de Araújo Filho, Jéssica Maria Leite dos Santos, Ana Paula Negreiros Nunes Alves, Jomar Patrício Monteiro, Selene Maia de Morais, Isaac Neto Goes da Silva, Lorena Mayana Beserra de Oliveira, Flávia Oliveira Monteiro da Silva Abreu, Claudia Maria Leal Bevilaqua
Revista Brasileira de Parasitologia Veterinária  vol: 29  issue: 1  year: 2020  
doi: 10.1590/s1984-29612019098

174. Prevalence of anthelmintic resistance of gastrointestinal nematodes in Polish goat herds assessed by the larval development test
Marcin Mickiewicz, Michał Czopowicz, Agata Moroz, Adrian-Valentin Potărniche, Olga Szaluś-Jordanow, Marina Spinu, Paweł Górski, Iwona Markowska-Daniel, Marián Várady, Jarosław Kaba
BMC Veterinary Research  vol: 17  issue: 1  year: 2021  
doi: 10.1186/s12917-020-02721-9

175. Prevalence of gastrointestinal parasites in small ruminants in Grenada, West Indies
Camille-Marie Coomansingh-Springer, Camila de Queiroz, Ray Kaplan, Calum N.L. Macpherson, Kenrith Carter, Paul Fields, John S. Gilleard, Rhonda Pinckney
Veterinary Parasitology: Regional Studies and Reports  vol: 59  first page: 101218  year: 2025  
doi: 10.1016/j.vprsr.2025.101218

176. In vivo efficacy of macrocyclic lactones on goat farms – pour-on vs injectable application
Michal Babják, Alžbeta Königová, Tetiana A. Kuzmina, Marián Várady
Journal of Veterinary Research  vol: 69  issue: 2  first page: 293  year: 2025  
doi: 10.2478/jvetres-2025-0025

177. Effect of injectable eprinomectin on milk quality and yield of dairy ewes naturally infected with gastrointestinal nematodes
Sofia-Afroditi Termatzidou, Nektarios Siachos, Panagiota Kazana, Smaragda Sotiraki, Katerina Saratsi, Damien Achard, Hamadi Karembe, Georgios Bramis, Vasileios Kanoulas, Georgios Arsenos
Veterinary Parasitology  vol: 286  first page: 109245  year: 2020  
doi: 10.1016/j.vetpar.2020.109245

178. Electrochemical enzyme-linked immunosorbent assay (e-ELISA) for parasitic nematode Ostertagia ostertagi (brown stomach worm) infections in dairy cattle
Baljit Singh, Evangelia Flampouri, Eithne Dempsey
The Analyst  vol: 144  issue: 19  first page: 5748  year: 2019  
doi: 10.1039/C9AN00982E

179. Identification of somatic proteins in Haemonchus contortus infective larvae (L3) and adults
M. Zaragoza-Vera, R. González-Garduño, L. Brito-Argáez, A. J. Aguilar-Caballero, C. V. Zaragoza-Vera, G. Arjona-Jiménez, V. M. Loyola-Vargas, V. Aguilar-Hernández, O. M. Torres-Chable
Helminthologia  vol: 59  issue: 2  first page: 143  year: 2022  
doi: 10.2478/helm-2022-0017

180. Systematic review of the prevalence of Gastrointestinal helminths in ruminants in Mexico
Roberto González-Garduño, Rosa Isabel Higuera-Piedrahita, Jorge Alfredo Cuéllar-Ordaz, Abel Villa-Mancera, Pedro Mendoza-de Gives, J. Felipe Torres-Acosta
Veterinary Research Communications  vol: 50  issue: 1  year: 2026  
doi: 10.1007/s11259-025-10968-6

181. Morbidity Parameters Associated with Gastrointestinal Tract Nematodes in Sheep in Dabat District, Northwest Ethiopia
Zewdu Seyoum, Kalkidan Getnet, Mersha Chanie, Samuel Derso, Shumye Fentahun
BioMed Research International  vol: 2018  first page: 1  year: 2018  
doi: 10.1155/2018/9247439

182. Curcumin-PVP improves the in vitro efficacy of ivermectin against resistant and susceptible Haemonchus contortus
Lisandro Alberto Encalada-Mena, Raquel López-Arellano, María Eugenia López-Arellano, María Gabriela Mancilla-Montelongo, Carlos Alfredo Sandoval-Castro, Agustín Olmedo-Juárez, Adrián Lifschitz, Juan Felipe de Jesús Torres-Acosta
Experimental Parasitology  vol: 256  first page: 108670  year: 2024  
doi: 10.1016/j.exppara.2023.108670

183. Anthelmintic resistance against gastrointestinal nematodes: an emerging threat in cattle farms in Bangladesh
Sawda Khatun, Anisuzzaman, Nusrat Nowrin Shohana, Kausar A. Noor, Mohammad Zahangir Alam, Anita Rani Dey
Journal of Parasitic Diseases  vol: 49  issue: 3  first page: 747  year: 2025  
doi: 10.1007/s12639-025-01798-z

184. Field-based and molecular evaluation of anthelmintic resistance in gastrointestinal strongyle nematodes of meat goats in Southern Thailand
Narin Sontigun, Chalutwan Sansamur, Tunwadee Klong-Klaew, Raktham Mektrirat, Morakot Kaewthamasorn, Punpichaya Fungwithaya
Veterinary World  first page: 2467  year: 2025  
doi: 10.14202/vetworld.2025.2467-2478

185. Anthelmintic activity of winter savory (Satureja montana L.) essential oil against gastrointestinal nematodes of sheep
Filip Štrbac, Slobodan Krnjajić, Radomir Ratajac, Laura Rinaldi, Vincenzo Musella, Fabio Castagna, Dragica Stojanović, Nataša Simin, Dejan Orčić, Antonio Bosco
BMC Veterinary Research  vol: 21  issue: 1  year: 2025  
doi: 10.1186/s12917-025-04771-3

186. The identification and semi-quantitative assessment of gastrointestinal nematodes in faecal samples using multiplex real-time PCR assays
Nikol Reslova, Lucie Skorpikova, Iveta Angela Kyrianova, Jaroslav Vadlejch, Johan Höglund, Philip Skuce, Martin Kasny
Parasites & Vectors  vol: 14  issue: 1  year: 2021  
doi: 10.1186/s13071-021-04882-4

187. Significance of anti-CarLA salivary IgA antibody in first grazing season cattle naturally infected with gastrointestinal nematodes
Aurélie Merlin, Richard Shaw, Alain Chauvin, Nathalie Bareille, Christophe Chartier
Veterinary Parasitology  vol: 243  first page: 36  year: 2017  
doi: 10.1016/j.vetpar.2017.06.006

188. Participatory surveillance reveals marsh deer mortality event during an extraordinary flood in Ibera Wetlands, Argentina
M. M. Orozco, E. C. Guillemi, L. Minatel, A. Schapira, K. Caimi, Y. Berra, P. Blanco, D. Di Nucci, M. D. Farber, M. Pilar Fernández, H. D. Argibay
Ecosphere  vol: 16  issue: 2  year: 2025  
doi: 10.1002/ecs2.70186

189. A multiplex PCR-based method to identify strongylid parasite larvae recovered from ovine faecal cultures and/or pasture samples
S.A. Bisset, J.S. Knight, C.L.G. Bouchet
Veterinary Parasitology  vol: 200  issue: 1-2  first page: 117  year: 2014  
doi: 10.1016/j.vetpar.2013.12.002

190. Efficacy of Duddingtonia flagrans spores fed in trace mineral mix to lambs in reducing the development of gastrointestinal nematode larvae in feces
Joan M. Burke, Suman Rohila, Elisa Preston, Cathleen C. Williams, Clare M. Scully, Brooke A. Delcambre, Katherine H. Petersson, Elizabeth Kass, Mohan Acharya, James E. Miller, Adriano F. Vatta
Veterinary Parasitology  vol: 334  first page: 110414  year: 2025  
doi: 10.1016/j.vetpar.2025.110414

191. Haemonchus contortus Susceptibility and Resistance to Anthelmintics in Naturally Infected Egyptian Sheep
Shawky M. Aboelhadid, Waleed M. Arafa, Saeed El-Ashram, Asmaa Fathy Noaman, Khalid A. Shokier, Ahmed B. Darwish, Morad M. Mahmoud, Sahar M. Gadelhaq
Acta Parasitologica  vol: 66  issue: 2  first page: 329  year: 2021  
doi: 10.1007/s11686-020-00284-1

192. Integrating the control of helminths in dairy cattle: Deworming, rotational grazing and nutritional pellets with parasiticide fungi
Mathilde Voinot, Cristiana Cazapal-Monteiro, José Ángel Hernández, Antonio Miguel Palomero, Fabián Leonardo Arroyo, Jaime Sanchís, José Pedreira, Rita Sánchez-Andrade, Adolfo Paz-Silva, María Sol Arias
Veterinary Parasitology  vol: 278  first page: 109038  year: 2020  
doi: 10.1016/j.vetpar.2020.109038

193. An Artemisia cina n-hexane extract reduces the Haemonchus contortus and Teladorsagia circumcincta fecal egg count in naturally infected periparturient goats
Rosa Isabel Higuera-Piedrahita, Mariana Dolores-Hernández, Héctor Alejandro de la-Cruz-Cruz, Héctor Mario Andrade-Montemayor, Alejandro Zamilpa, Raquel López-Arellano, Roberto González-Garduño, Jorge Alfredo Cuéllar-Ordaz, Pedro Mendoza-de-Gives, Ma. Eugenia López-Arellano
Tropical Animal Health and Production  vol: 54  issue: 2  year: 2022  
doi: 10.1007/s11250-022-03103-z

194. The faecal egg count reduction test: Will identification of larvae to species improve its utility?
Dave Leathwick, Peter Green, Charlotte Bouchet, Alex Chambers, Tania Waghorn, Christian Sauermann
International Journal for Parasitology: Drugs and Drug Resistance  vol: 27  first page: 100589  year: 2025  
doi: 10.1016/j.ijpddr.2025.100589

195. Supplementation with dry Mimosa caesalpiniifolia leaves can reduce the Haemonchus contortus worm burden of goats
D.R.B. Brito, L.M. Costa-Júnior, J.L. Garcia, J.F.J. Torres-Acosta, H. Louvandini, J.A.A. Cutrim-Júnior, J.F.M. Araújo, E.D.S. Soares
Veterinary Parasitology  vol: 252  first page: 47  year: 2018  
doi: 10.1016/j.vetpar.2018.01.014

196. Effects of age, sex, lactation and social dominance on faecal egg count patterns of gastrointestinal nematodes in farmed eland (Taurotragus oryx)
J. Vadlejch, R. Kotrba, Z. Čadková, A. Růžičková, I. Langrová
Preventive Veterinary Medicine  vol: 121  issue: 3-4  first page: 265  year: 2015  
doi: 10.1016/j.prevetmed.2015.07.006

197. Identifying the genotype of parasitic nematodes Teladorsagia circumcincta resistant to benzimidazole anthelmintics
I. A. Pimenov, I. M. Odoevskaya
Russian Journal of Parasitology  vol: 19  issue: 2  first page: 263  year: 2025  
doi: 10.31016/1998-8435-2025-19-2-263-271

198. Gastrointestinal nematode species diversity in Soay sheep kept in a natural environment without active parasite control
Rona Sinclair, Lynsey Melville, Fiona Sargison, Fiona Kenyon, Dan Nussey, Kathryn Watt, Neil Sargison
Veterinary Parasitology  vol: 227  first page: 1  year: 2016  
doi: 10.1016/j.vetpar.2016.07.020

199. Evaluation of the pour-on administration of eprinomectin on milk yield and somatic cell counts in dairy ewes naturally infected with gastrointestinal nematodes
K. Arsenopoulos, A.I. Gelasakis, V. Delistamatis, E. Papadopoulos
Veterinary Parasitology  vol: 276  first page: 100016  year: 2019  
doi: 10.1016/j.vpoa.2019.100016

200. Est-il possible d’élever des génisses de race Gasconne des Pyrénées au pâturage sans aucun traitement strongylicide ?
Philippe Jacquiet, Alix Aldebert, Delphine De Cherade de Monbron, Christelle Grisez, Françoise Prevot, Frédéric Piquemal, Jean-Pierre Gajan, Emeric Jouhet, Julie Petermann
Le Nouveau Praticien Vétérinaire élevages & santé  vol: 17  issue: 61  first page: 32  year: 2025  
doi: 10.1051/npvelsa/2025050

201. Multiple anthelmintic resistance in Southern Brazil sheep flocks
Plínio Aguiar de Oliveira, Beatriz Riet-Correa, Pablo Estima-Silva, Ana Carolina Barreto Coelho, Bianca Lemos dos Santos, Marco André Paldês Costa, Jerônimo Lopes Ruas, Ana Lucia Schild
Revista Brasileira de Parasitologia Veterinária  vol: 26  issue: 4  first page: 427  year: 2017  
doi: 10.1590/s1984-29612017058

202. Possibilities of using nested PCR-RFLP for taxonomic identification of L3 larvae of the family Trichostrongylidae, Leiper, 1912
I. A. Pimenov, I. M. Odoevskaya, A. M. Plieva, A. I. Varlamova
Russian Journal of Parasitology  vol: 18  issue: 3  first page: 264  year: 2024  
doi: 10.31016/1998-8435-2024-18-3-264-273

203. Prevalences and characteristics of Trichuris spp. infection in sheep in pastoral areas of the Tianshan, Xinjiang, China
Lixia Wang, Guowu Zhang, Yuhang Fu, Chengcheng Ning, Zhiyuan Li, Huisheng Wang, Jinsheng Zhang, Yunxia Shang, Yaoqiang Sun, Xiaoxing Huang, Xuepeng Cai, Xianzhu Xia, Qingling Meng, Jun Qiao
Journal of Veterinary Research  vol: 66  issue: 4  first page: 591  year: 2022  
doi: 10.2478/jvetres-2022-0056

204. In vitro and in vivo anthelmintic efficacy of peppermint (Mentha x piperita L.) essential oil against gastrointestinal nematodes of sheep
Filip Štrbac, Slobodan Krnjajić, Dragica Stojanović, Radomir Ratajac, Nataša Simin, Dejan Orčić, Laura Rinaldi, Elena Ciccone, Maria Paola Maurelli, Giuseppe Cringoli, Antonio Bosco
Frontiers in Veterinary Science  vol: 10  year: 2023  
doi: 10.3389/fvets.2023.1232570

205. Molecular method for the semiquantitative identification of gastrointestinal nematodes in domestic ruminants
Lívia L. Santos, Jordana A. Salgado, Marcela G. Drummond, Eduardo Bastianetto, Clóvis P. Santos, Bruno S. A. F. Brasil, Cesar A. Taconeli, Denise A. A. Oliveira
Parasitology Research  vol: 119  issue: 2  first page: 529  year: 2020  
doi: 10.1007/s00436-019-06569-3

206. Can the strategies for endoparasite control affect the productivity of lamb production systems on pastures?
Maria Angela Machado Fernandes, Jordana Andrioli Salgado, Mylena Taborda Piquera Peres, Karla Francisca Duarte Campos, Marcelo Beltrão Molento, Alda Lúcia Gomes Monteiro
Revista Brasileira de Zootecnia  vol: 48  year: 2019  
doi: 10.1590/rbz4820180270

207. In vitro synergy analysis of the combination of Citrus aurantium bergamia (Risso & Poiteau, 1826), ivermectin, and nitroxinil against gastrointestinal nematodes of sheep
Vivien Patricia Garbin, Ursula Yaeko Yoshitani, Taynara Gabriele Ribeiro Piano, Roger Raup Cipriano, Cícero Deschamps, Gustavo Fonseca De Almeida, Marcelo Beltrão Molento
Veterinary Parasitology: Regional Studies and Reports  vol: 66  first page: 101384  year: 2025  
doi: 10.1016/j.vprsr.2025.101384

208. Assessment on bioactive role of Moringa oleifera leaves as anthelmintic agent and improved growth performance in goats
Juan Pedraza-Hernández, Mona M. M. Y. Elghandour, Ameer Khusro, Mohamed Z. M. Salem, Luis M. Camacho-Diaz, Alberto Barbabosa-Pliego, Abdelfattah Z. M. Salem
Tropical Animal Health and Production  vol: 53  issue: 2  year: 2021  
doi: 10.1007/s11250-021-02745-9

209. Epidemiology of caprine gastrointestinal nematodes and associated efficacy of anthelmintic drugs in Punjab districts, India
Amanpreet Kaur, Nirmaljeet Kaur, Karishma Chauhan, Jyoti, Harkirat Singh, Nirbhay Kumar Singh
Scientific Reports  vol: 15  issue: 1  year: 2025  
doi: 10.1038/s41598-025-89784-6

210. Microclimate has a greater influence than macroclimate on the availability of infective Haemonchus contortus larvae on herbage in a warmed temperate environment
Tong Wang, Hannah Rose Vineer, Alison Morrison, Jan A. van Wyk, Muhammad-Bashir Bolajoko, David J. Bartley, Eric R. Morgan
Agriculture, Ecosystems & Environment  vol: 265  first page: 31  year: 2018  
doi: 10.1016/j.agee.2018.05.029

211. A fecal egg count reduction test in grazing beef steers using topical pioneer and generic eprinomectin and fenbendazole oral suspension
Eva Wray, Christopher A. Tucker, Jana L. Reynolds, Ben Shoulders, Kirsten Midkiff, Jeremy G. Powell
Veterinary Parasitology: Regional Studies and Reports  vol: 46  first page: 100937  year: 2023  
doi: 10.1016/j.vprsr.2023.100937

212. Development of a loop-mediated isothermal amplification detection assay for Dictyocaulus viviparus (Bloch, 1782) lungworm: DviLAMP
Sirapat Nak-on, Paul Campbell, Maha Mansour Shalaby, Jennifer McIntyre, Alistair Antonopoulos, Thapana Chontananarth, Roz Laing
Frontiers in Veterinary Science  vol: 11  year: 2024  
doi: 10.3389/fvets.2024.1454065

213. Co-grazing of sheep and goats may not be an issue from a parasitological perspective
I. A. Kyriánová, I. Knížková, M. Ptáček, J. Nápravníková, O. Kopecký, T. Husák, J. Vadlejch
Helminthologia  vol: 62  issue: 3  first page: 175  year: 2025  
doi: 10.2478/helm-2025-0030

214. Status of benzimidazole resistance in Haemonchus contortus of goats from different geographic regions of Uttar Pradesh, India
S. Chandra, A. Prasad, N. Yadav, A. Latchumikanthan, R.L. Rakesh, K. Praveen, V. Khobra, K.V. Subramani, J. Misri, M. Sankar
Veterinary Parasitology  vol: 208  issue: 3-4  first page: 263  year: 2015  
doi: 10.1016/j.vetpar.2015.01.005

215. Resistance of strongylid nematodes to anthelmintic drugs and driving factors at Czech goat farms
Jaroslav Vadlejch, Iveta Angela Kyriánová, Marián Várady, Johannes Charlier
BMC Veterinary Research  vol: 17  issue: 1  year: 2021  
doi: 10.1186/s12917-021-02819-8

216. Evaluación antihelmíntica in vitro de curcumina contra huevos y larvas de aislados de Haemonchus contortus con distinta susceptibilidad a ivermectina
Lisandro Alberto Encalada-Mena, Raquel López-Arellano, Maria Eugenia López-Arellano, Maria Gabriela Mancilla-Montelongo, Carlos Alfredo Alfredo Sandoval-Castro, Agustín Olmedo-Juárez, Juan Felipe de Jesús Torres-Acosta
Revista Mexicana de Ciencias Pecuarias  vol: 15  issue: 4  first page: 811  year: 2024  
doi: 10.22319/rmcp.v15i4.6440

217. Epidemiology and larval morphology of Nematodirus spp. in sheep raised under traditional husbandry system In district Kargil, a Trans-Himalaya region of India
Shabbir Hussain, Aqleemul Islam, Zeenat Islam, Fayaz Ahmad, Kamal Jaiswal, Suman Mishra
Journal of Parasitic Diseases  year: 2025  
doi: 10.1007/s12639-025-01865-5

218. Helminth parasites transmission between species of ruminants in urban and peri-urban areas of Adaa district of Central Ethiopia
Alkadir Gebeyehu, Ayana Dinka, Wakjira Guta, Fatalo Tesfaye
Journal of Veterinary Medicine and Animal Health  vol: 16  issue: 1  first page: 1  year: 2024  
doi: 10.5897/JVMAH2023.1046

219. Alterations in Goat Microbiota Following Panax notoginseng Supplementation: Metagenomic Insights and Potential for Gastrointestinal Nematode Control
Yonathan Tilahun, Adekayode Sonibare, Zaisen Wang
American Journal of Molecular Biology  vol: 15  issue: 04  first page: 277  year: 2025  
doi: 10.4236/ajmb.2025.154019

220. Molecular detection of benzimidazole resistance in Haemonchus contortus: A comparative analysis of field and abattoir larval isolates from sheep and goats
Mohamed A. Helal, Prashant D. Pawar, Lachhman Das Singla
Small Ruminant Research  vol: 250  first page: 107555  year: 2025  
doi: 10.1016/j.smallrumres.2025.107555

221. The effect of pumpkin seed cake and ground cloves (Syzygium aromaticum) supplementation on gastrointestinal nematode egg shedding in sheep
Jožica Ježek, Karmen Mirtič, Nina Rešetič, Jaka Jakob Hodnik, Aleksandra Vergles Rataj
Parasite  vol: 28  first page: 78  year: 2021  
doi: 10.1051/parasite/2021076

222. Gastro-intestinal nematodes in goats in Bangladesh: A large-scale epidemiological study on the prevalence and risk factors
Anita Rani Dey, Nurjahan Begum, Md. Abdul Alim, Subrota Malakar, Md. Taohidul Islam, Mohammad Zahangir Alam
Parasite Epidemiology and Control  vol: 9  first page: e00146  year: 2020  
doi: 10.1016/j.parepi.2020.e00146

223. Anthelmintic effects of forage chicory (Cichorium intybus) against gastrointestinal nematode parasites in experimentally infected cattle
MIGUEL PEÑA-ESPINOZA, STIG M. THAMSBORG, OLIVIER DESRUES, TINA V. A. HANSEN, HEIDI L. ENEMARK
Parasitology  vol: 143  issue: 10  first page: 1279  year: 2016  
doi: 10.1017/S0031182016000706

224. The first report of multidrug resistance in gastrointestinal nematodes in goat population in Poland
Marcin Mickiewicz, Michał Czopowicz, Ewelina Kawecka-Grochocka, Agata Moroz, Olga Szaluś-Jordanow, Marián Várady, Alżbeta Königová, Marina Spinu, Paweł Górski, Emilia Bagnicka, Jarosław Kaba
BMC Veterinary Research  vol: 16  issue: 1  year: 2020  
doi: 10.1186/s12917-020-02501-5

225. In vitro anthelmintic activity of an aqueous extract of Glycyrrhiza glabra and of glycyrrhetinic acid against gastrointestinal nematodes of small ruminants
Michela Maestrini, Marcelo Beltrão Molento, Mario Forzan, Stefania Perrucci
Parasite  vol: 28  first page: 64  year: 2021  
doi: 10.1051/parasite/2021060

226. Helminth infections in alpacas (Vicugna pacos), husbandry and worm control practices in South American Camelids in Italy
Elisa Castaldo, Francesco Buono, Stefano Scarcelli, Alessia Ciaramelli, Michele Capasso, Sara Tonon, Giovanni Sgroi, Rudi Cassini, Walter Basso, Vincenzo Veneziano
The Veterinary Journal  vol: 314  first page: 106445  year: 2025  
doi: 10.1016/j.tvjl.2025.106445

227. Isolation of pure Trichostrongylus colubriformis strains from naturally infected sheep using two methodologies
Alhely Can-Celis, Gabriela Mancilla-Montelongo, Gloria Sarahi Castañeda-Ramírez, José Israel Chan-Pérez, Juan Felipe de Jesús Torres-Acosta
Veterinary Parasitology: Regional Studies and Reports  vol: 22  first page: 100474  year: 2020  
doi: 10.1016/j.vprsr.2020.100474

228. Selection of Genome-Wide SNPs for Pooled Allelotyping Assays Useful for Population Monitoring
Marielle Babineau, Eliza Collis, Angela Ruffell, Rowan Bunch, Jody McNally, Russell E Lyons, Andrew C Kotze, Peter W Hunt, Maria Costantini
Genome Biology and Evolution  vol: 14  issue: 3  year: 2022  
doi: 10.1093/gbe/evac030