Disease seen in yearling animals

Signs of yersiniosis in yearling animals are a tucked up appearance and faecal staining around the backside.

Yersiniosis: A disease for yearling calves over the summer

Yersiniosis sp is a bacteria that causes outbreaks of enteritis or diarrhoea in cattle — often single cases although we see outbreaks in weaner calves shifted to grazing in the Western Bay of Plenty.

It is a disease that mainly involves young animals after weaning (deer too) during inclement weather.

Infection is by the faecal-oral route. For the organism to cause disease, contributing factors such as inclement weather, management stress (eg. mustering, transport, calving), feed shortages and concurrent parasitism need to be present.

It sometimes is notable that it can occur on well fed animals on lush green pasture. Some circumstantial evidence suggests active Bovine Viral Diarrhoea Virus (BVDV) infection can allow Yersinia infection to develop. Animals with diarrhoea tend to cause heavy environmental contamination, resulting in rapid exposure to other susceptible animals.

The diarrhoea is a light green, brownish in colour and not malodorous.

Affected animals are commonly depressed and dehydrated. We diagnose the infection by confirming the organism by faecal culture. Note we can culture the organism in about 26 per cent of healthy cows and 84 per cent of farms.

Management of an outbreak is treatment with specific antibiotics that the organism is sensitive to and electrolytes. Spreading the herd out (avoid overcrowding), rising plane of nutrition +/- supplementary feed/calf meal.

Overall control can be achieved by minimising the impact of predisposing factors and stressors. Attention to good transition weaning, nutrition, mineral supplementation, parasite control, transport stress, shelter and BVDV prevention.