Prevalence and clinical significance of leptospiral antibodies in pigs in England.

The results of leptospiral serology conducted on porcine sera at the Central Veterinary Laboratory, Weybridge from 1971 to 1978 were collated and analysed. Sera were available from diagnostic submissions (1622) and from pigs intended fro export (5031). A random sample of 792 sera from 34 herds was also examined. The overall prevalence of infection was low. Copenhageni titres were present in 7.9 per cent of diagnostic submissions and a statistical association with jaundice was shown in piglets and adults. The introduction of Australis serogroup antigens in 1978 revealed the serological prevalences to lora and bratislava to be in excess of 20 per cent. However the causative serotype has yet to be identified. Leptospiral infection was not a significant cause of abortion in pigs. The pattern of leptospiral infection in pigs in England is considerably different from that occurring in other countries and it is considered that free-living maintenance host populations constitute the primary sources of infection.