White muscle disease in cattle is caused by deficiency of which mineral?

• A. Selenium
• B. Vitamin E
• C. Calcium
• D. Phosphorus

Answer: (A)

Nutritional muscular dystrophy, or white muscle disease, is tied to a deficiency of a trace mineral that plays a key antioxidant role in muscle tissue. Selenium is essential because it is part of the enzyme glutathione peroxidase, which helps protect muscle cells from oxidative damage. When selenium is deficient, muscles—especially the fast-growing skeletal and heart muscles—are damaged, leading to the pale, “white” streaks and weakness characteristic of the condition. That link makes selenium the mineral responsible for this disease.

Calcium and phosphorus deficiencies cause different problems, mainly related to bones and calcium balance, not the oxidative-muscle damage seen in white muscle disease. Vitamin E is involved as an antioxidant and can influence the condition, but it’s a vitamin, not a mineral, which is why the mineral linked to this disease is selenium. In practice, preventing selenium deficiency through appropriate supplementation in at-risk herds is the key strategy.