Infection by leptospires of the Pomona serogroup in cattle and pigs in south west England.

Leptospires belonging to the Pomona serogroup were isolated from calves involved in two outbreaks of acute haemolytic disease which were characterised by jaundice, haemoglobinuria and high death rates. Retrospective case studies in which serological evidence of Pomona serogroup infection was found are also presented. Serovar pomona is the leptospire of the Pomona serogroup most commonly incriminated in clinical disease in domestic species, but the organisms isolated in this study were antigenically different to pomona and may represent a new serovar. The limited information available on the epidemiology of sporadic infection with leptospires of the Pomona serogroup in domestic species in the south west of England supports the contention that a serovar other than pomona is involved.