Livestock

Polioencephalomalacia in Cattle: Welfare and Treatment

Welfare guide to polioencephalomalacia in cattle -- a thiamine deficiency causing neurological disease.

Key Facts

Polioencephalomalacia (PEM) is a metabolic brain disease caused by thiamine (Vitamin B1) deficiency
Affected cattle show nervous signs including head pressing, blindness, circling, and recumbency
It affects young growing cattle and can occur in animals on various diets including high-sulphur feeds
High-sulphur forages and water can increase thiamine antagonism -- a risk factor for PEM
Prompt treatment with high-dose thiamine by injection is dramatically effective in early cases
Delayed treatment leads to irreversible brain damage and death -- prognosis worsens rapidly with delay
Welfare deterioration is severe -- affected animals are disoriented, blind, and unable to self-maintain
Prevention includes avoiding high-sulphur feeds and ensuring adequate thiamine in the diet

Welfare Significance

Polioencephalomalacia causes acute severe neurological distress -- affected cattle are blind, disoriented, and often recumbent. The welfare emergency requires immediate veterinary treatment. The response to thiamine is dramatic when treatment is prompt -- cattle can recover from apparent near-death within hours. Delay in recognising and treating PEM condemns animals to preventable brain damage and death.

What You Can Do

Recognise PEM signs immediately -- any cattle showing blindness and nervous signs require emergency veterinary attention
Have injectable thiamine available on farm for emergency treatment while the vet is called
Avoid high-sulphur forages and water as primary risk factor management
Discuss dietary thiamine adequacy with your vet or nutritionist when using any novel or high-sulphur feeds