Abstract
Outbreaks of salmonellosis caused by serotypes other than S. dublin and S. typhimurium were investigated on 41 farms in north-west England. Of these, 37 (90 per cent) were in dairy cows. There was strong circumstantial evidence that contaminated dairy cake was the source of infection in at least four herds and probably many more. Twenty-six serotypes were encountered with S. newport, the commonest, causing the most severe disease. Most cattle seemed to rid themselves of infection during the following months whether or not they were at pasture, housed in cubicles or in byres. Some cows excreted salmonellas for up to 11 months after the disease outbreak. Associated human salmonellosis was confirmed on 3/41 (7 per cent) of the farms.