Ill-thrift in Merino ewe weaners
- Ill-thrift, weakness, diarrhoea and deaths were seen in 4–6-month-old Merino weaners in the Wheatbelt.
- In total, 30 weaners died and 70 weaners were affected from a mob of 700.
- The weaners were grazing canola stubble with ad lib lupins via feeders and were supplemented with hay.
- The weaners were vaccinated for pulpy kidney as lambs and received a booster when losses began.
- Blood samples, small intestinal swabs, fresh and fixed tissue samples and rumen content were all submitted for laboratory examination.
- Testing for annual ryegrass toxicity of rumen content and enterotoxaemia was negative, and intestinal worm egg counts and Salmonella cultures were negative.
- Following laboratory testing and bacterial culture, infection with Vibrio cholerae was diagnosed. The serogroup detected was not one associated with severe human cholera outbreaks.
- V. cholerae is an unusual finding in gastroenteritis cases in sheep in samples tested at AHL.