Selenium deficiency causes white muscle disease in lambs and ewes, a painful and often fatal condition that is largely preventable with appropriate supplementation programs.
White muscle disease causes severe suffering — affected lambs cannot stand, struggle to suckle, and often die from heart failure or secondary pneumonia. The condition is particularly distressing because lambs are often found collapsed, unable to receive maternal care. Subclinical deficiency causes chronic poor condition and immune suppression that increases susceptibility to other diseases. Prevention through targeted supplementation of ewes before lambing and lambs at birth dramatically reduces incidence. Accurate soil and blood testing guides appropriate supplementation to avoid both deficiency and toxicity.