Selenium review highlights antioxidant role across livestock

A new review in Animals pulls together the evidence on selenium’s role in antioxidant defense across cattle, pigs, and small ruminants, arguing that the trace mineral remains central to herd and flock health during periods of oxidative stress, including transition, reproduction, heat stress, and disease challenge. The paper highlights selenium’s role in selenoproteins such as glutathione peroxidases and thioredoxin reductases, and reviews how selenium form, feed source, and species differences affect absorption, tissue retention, and biologic response. The authors also emphasize the narrow line between deficiency and excess, a practical issue in the U.S., where FDA rules generally cap selenium in complete feed for cattle, sheep, and swine at 0.3 ppm. (law.cornell.edu)

Why it matters: For veterinarians and nutrition advisers, the review is less about a new intervention than a timely reminder that selenium status still shapes immune function, fertility, neonatal vigor, and productivity, especially in selenium-deficient regions or under heat and metabolic stress. Background literature supports that deficiency is linked with conditions such as nutritional myopathies in ruminants and pigs, while newer pig and ruminant studies continue to show selenium’s effects on antioxidant capacity, inflammation, and tissue resilience. A second MDPI paper, in poultry rather than livestock, adds to the broader selenium literature by reporting dose-dependent benefits of selenomethionine for rooster semen quality during short-term liquid storage, reinforcing ongoing interest in organic selenium forms for reproductive performance. (merckvetmanual.com)

What to watch: Expect more focus on source-specific supplementation strategies, biomarker-guided monitoring, and species-specific dosing as researchers try to balance efficacy, regulation, and toxicity risk. (pubmed.ncbi.nlm.nih.gov)