1. Hannah Research Institute; Ayr KA6 5HL
2. Department of Veterinary Clinical Studies; University of Glasgow; Bearsden Road Glasgow G61 1QH
3. Dairy Health Unit; Scottish Agricultural College Veterinary Services; Auchincruive Ayr KA6 SAE
4. University of Glasgow; Department of Bacteriology, Glasgow Royal Infirmary; Castle Street Glasgow G4 OSF