The incidence of Salmonella bacteria in wild-living animals from Denmark and in imported animals.

In a 6 year examination (1975-80) of 3036 game mammals and 3004 game birds from Denmark, and of 684 warm-blooded animals of foreign origin, Salmonella was found in 0.2% of Danish mammals, 0.8% of danish game birds, and 0.1% of the animals of foreign origin. Furthermore, Salmonella was isolated from 16% of 605 mute swans which died from starvation during the winter 1978-79, and from 2.4% of 296 faeces samples from hooded crows. Even though the occurrence of Salmonella among Danish cattle has been increasing during recent years, this does not seem to be the case among game, mallards excepted. Mallards raised in breeding units are often treated with antibiotics as a routine; in this way the mortality due to Salmonella is reduced, but some birds will still carry Salmonella bacteria when released. The high salmonella frequency among the mute swans that died during the winter of 1978-79 was probably a result of large numbers of birds gathering in harbours or in small stretches of open water near sew outlets.