Original Research

Injectable organic and inorganic selenium in dairy cows – Effects on milk, blood and somatic cell count levels

Gert M. Ferreira, Inge-Marie Petzer
Onderstepoort Journal of Veterinary Research | Vol 86, No 1 | a1664 | DOI: https://doi.org/10.4102/ojvr.v86i1.1664 | © 2019 Gert M. Ferreira, Inge-Marie Petzer | This work is licensed under CC Attribution 4.0
Submitted: 23 June 2018 | Published: 08 October 2019

About the author(s)

Gert M. Ferreira, Morvet Veterinary Practise, Potchefstroom, South Africa
Inge-Marie Petzer, Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa


Mastitis is the most costly disease of dairy cows. A pro-active approach includes insuring adequate levels of selective trace minerals. The aim of this study was to determine the effect of two different commercially available, injectable selenium products, (sodium) Na-selenite (inorganic) and (selenium) Se-methionine (organic), on milk composition and on serum and milk selenium concentrations in high-yielding Holstein cows on total mix ration. Sixty multiparous cows were randomly selected into three groups of 20, one control group and two groups supplemented with injectable trace minerals. Blood and milk samples were collected over a period of 60 days. No specific change was indicated in milk yield, lactose, milk urea nitrogen (MUN) and milk pH levels compared with baseline values. The Se-methionine supplemented group showed a numerical increase in total milk protein percentage. In the group injected with Se-methionine, a negative correlation was present for the initial 72 hours between serum selenium concentration and somatic cell count (SCC) and a highly significant (p < 0.001) increase in milk selenium concentration for the initial 24 hours. Serum selenium concentration of Se-methionine-supplemented cows was however not significantly changed. Injection of Na-selenite led to a 60-day initial increase in serum selenium concentration above baseline levels and a significant milk selenium concentration on day 1 but to a negative correlation between serum selenium concentration and SCC. Differences in serum and milk selenium concentrations followed with the use of organic and inorganic selenium injectables. Injectable Na-selenite, as selenium, can be of important value for cattle farmers if supplemented on strategically physiological periods to improve production, reproduction and immunity.


dairy cows; injectable selenium; Na-selenite; Se-methionine; serum selenium; milk selenium, SCC; somatic cell count


Total abstract views: 3133
Total article views: 3214


Crossref Citations

1. The Association between Selected Dietary Minerals and Mastitis in Dairy Cows—A Review
Kacper Libera, Kacper Konieczny, Katarzyna Witkowska, Katarzyna Żurek, Małgorzata Szumacher-Strabel, Adam Cieslak, Sebastian Smulski
Animals  vol: 11  issue: 8  first page: 2330  year: 2021  
doi: 10.3390/ani11082330