The Role of Vitamin E and Selenium in Sheep Health and Productivity

Pashu Sandesh, 02 June 2025

Dushyant Kumar¹, Amit Kulhar¹, Monika Karnani²

¹PG Scholar, Department of Livestock Products Technology

²Assistant Professor, Department of Animal Nutrition

Post Graduate Institute of Veterinary Education and Research, Jaipur

Rajasthan University of Veterinary and Animal Sciences, Jobner, Jaipur

Email: - d.k.jindal721991@gmail.com

Abstract

Vitamin E and Selenium (Se) are essential micronutrients that play synergistic roles in the health and productivity of sheep. While both serve as antioxidants, their combined effect helps prevent various disorders, including White Muscle Disease (WMD), reproductive inefficiency, and compromised immunity. This paper explores their biological roles, dietary sources, deficiency symptoms, and implications on sheep welfare and productivity.

Keywords: Muscular weakness, oxidative damage, selenium deficiency, reproduction, immune response

Introduction

Vitamin E is a fat-soluble antioxidant essential for maintaining cellular integrity in sheep. It protects tissues from oxidative damage and supports immune and reproductive functions. However, sheep often require supplementation due to fluctuations in pasture quality.

Selenium, a trace mineral, works in tandem with Vitamin E by enhancing enzymatic defense systems. The enzyme glutathione peroxidase, dependent on selenium, reduces peroxides and shields cells from oxidative stress. Deficiencies in either or both nutrients can lead to serious health consequences, including WMD and reproductive failures.

Antioxidant Protection and Muscle Health

Vitamin E helps stabilize cell membranes by preventing lipid peroxidation, especially in muscle tissues. A deficiency can lead to WMD, a condition that causes stiffness, muscle degeneration, and in severe cases, sudden death (Radostits et al., 2007).

Selenium deficiency also leads to muscular disorders and accelerates tissue damage. It contributes to oxidative stress by reducing glutathione peroxidase activity. During high metabolic demand—such as rapid growth, lactation, or stress—sheep are particularly vulnerable to deficiencies.

Antioxidants like Vitamin E and Selenium play a preventive role against cellular aging and tissue necrosis. Their use is particularly important in intensive production systems where oxidative challenges are elevated due to environmental and nutritional stress.

Immune System Support

Adequate levels of Vitamin E improve the function of T-lymphocytes and phagocytic cells, enhancing disease resistance. Studies suggest that sheep receiving sufficient Vitamin E show better antibody responses to vaccines and reduced mortality in lambs.

Selenium further boosts immunity by enabling neutrophil function and modulating cytokine production. Deficiency impairs the innate immune response and increases vulnerability to respiratory and gastrointestinal infections, especially in lambs during weaning and transportation.

Supplementation before major stress events, such as lambing or shearing, enhances immune resilience and reduces disease outbreaks in flocks.

Reproductive Performance

Vitamin E influences reproductive success by maintaining gamete viability and supporting embryonic development. Ewes deficient in Vitamin E may experience anestrus, retained placentas, and embryonic loss. In rams, it affects sperm motility and fertility (Abdel-Raheem et al., 2013).

Selenium also plays a vital role in reproductive health. It supports placental integrity, corpus luteum function, and sperm morphology. Supplementation improves conception rates, gestational outcomes, and overall reproductive efficiency.

Strategic supplementation before breeding enhances fertilization, embryo implantation, and fetal development, resulting in higher lambing rates and reduced perinatal losses.

Mechanism of Action on Reproductive Organs and Tissues

Dietary Sources and Supplementation

Green pasture is the richest source of natural Vitamin E and Selenium. However, levels decline in stored feed (e.g., hay and silage). Selenium content in forage depends on soil quality; deficiency is common in many geographic regions with selenium-poor soils.

Supplementation methods include:

• Oral administration: Drenches or mineral blocks
• Injectables: Often a Vitamin E + Selenium combination
• Feed fortification: With organic selenium forms for better absorption

Organic selenium (e.g., selenomethionine) is more bioavailable than inorganic forms. Similarly, natural Vitamin E (d-alpha-tocopherol) is more effective than synthetic dl-alpha-tocopherol.

A well-structured supplementation plan tailored to the production cycle ensures optimal nutrient availability and prevents metabolic disorders.

Signs of Deficiency

Combined or inpidual deficiencies of Vitamin E and Selenium manifest through several clinical and subclinical signs:

• Muscular stiffness or weakness (WMD)
• Poor growth and feed efficiency
• Increased infection rates
• Infertility and reproductive disorders
• Retained placentas
• Reduced wool quality
• Sudden death in lambs

Diagnosis is typically confirmed through blood tests or liver biopsies. Preventive supplementation is more effective and economical than therapeutic treatment after symptoms appear.

Conclusion

Vitamin E and Selenium are indispensable components of sheep nutrition. Their synergistic antioxidant functions protect against oxidative stress, support immune competence, and enhance reproductive efficiency. Seasonal variations, regional soil profiles, and feed storage methods necessitate careful supplementation planning.

Integrating these micronutrients into routine feeding strategies ensures improved flock health, higher productivity, and better economic outcomes for producers. Continuous monitoring and collaboration with veterinary nutritionists are key to avoiding deficiencies and maximizing livestock potential.

References

• Abdel-Raheem, S.M., Abd-Allah, S.M. & Hassanein, K.M.A. (2013). Effects of Vitamin E or Selenium Supplementation on Semen Quality and Antioxidant Markers in Rams. Journal of Animal and Veterinary Advances, 12(5), 597–602.
• McDowell, L.R. (2000). Vitamins in Animal and Human Nutrition (2nd ed.). Iowa State University Press.
• NRC (2007). Nutrient Requirements of Small Ruminants. National Academies Press.
• Radostits, O.M., Gay, C.C., Hinchcliff, K.W., & Constable, P.D. (2007). Veterinary Medicine (10th ed.). Saunders Elsevier.
• Weiss, W.P. (1998). Requirements of fat-soluble vitamins for dairy cows: A review. Journal of Dairy Science, 81(9), 2493–2501.