Tyzzer’s Disease Threatens Young Foals

Many horse owners have never heard of Tyzzer’s disease, though the illness was first described almost 100 years ago. This malady is a killer of newborn and young foals, striking most frequently in those less than six weeks of age. Affected foals are usually found comatose or dead only hours after appearing completely healthy.

Tyzzer’s disease is caused by a clostridial microbe that affects the liver and lower intestinal tract. Early indications of illness can include diarrhea and recumbency, but because these signs are not uncommon in very young foals, managers may not realize that a serious problem is present.

Foals of any breed and sex can be affected. There is no preventive vaccine, and effective treatments have not been found. The best defense against Tyzzer’s disease and other foal maladies is guaranteeing that the young horse has a high level of antibodies, either from ingesting sufficient colostrum in the first 12 hours after birth or by getting intravenous IgG-rich plasma to supply additional protection.