Pregnancy toxemia (twin lamb disease) is a metabolic disorder affecting ewes in late gestation that causes severe weakness, recumbency, and death if untreated, and is largely preventable through nutritional management.
Pregnancy toxemia causes profound suffering — ewes in advanced disease experience weakness, confusion, blindness from cerebral oedema, and seizures before death. The condition is almost entirely preventable through good nutritional management, making its continued prevalence a welfare failure rather than an inevitable outcome. Ewes carrying multiple fetuses have dramatically increased energy requirements in the final six weeks of pregnancy, and failure to meet these needs causes a cascade of metabolic derangements. Early recognition of at-risk ewes through body condition scoring and prompt dietary adjustment can prevent most cases. For affected ewes, prompt treatment with energy supplements is critical, as disease that progresses to recumbency carries a poor prognosis and prolonged suffering.