The disease may be severe in many domestic animals. Sheep appear to be more susceptible than cattle and goats are the least susceptible. Exotic breeds introduced into an endemic area appear to be more susceptible than breeds adapted to local conditions. Clinical signs in animals vary considerably and disease progression and severity are generally inversely proportional to age. The disease in animals is characterised by a short incubation period. Widespread abortion, infertility, and rapidly fatal neonatal disease are typical of outbreaks among cattle and sheep.