Campylobacter in the dog: a clinical and experimental study

Faecal samples from 54 dogs with diarrhoea and 54 control dogs were cultured for Campylobacter, Salmonella and Yersinia species and controlled for enteric viruses. The campylobacter were identified as either C jejuni/coli or C upsaliensis. In the diarrhoeic group 16 dogs (29.6 per cent) were positive for campylobacter, 10 C upsaliensis and six C jejuni/coli. Concomitant infection with parvovirus was evident in six of the dogs with diarrhoea and campylobacter-positive faecal cultures. In the control group 13 dogs (24.1 per cent) were positive for campylobacter; three of the isolates were C upsaliensis and six C jejuni/coli. Four isolates could not be identified. The most prominent clinical findings in naturally occurring cases were an acute onset of vomiting (12 of 16), diarrhoea (16 of 16) which was often haemorrhagic (nine of 16) and a raised rectal temperature. Dogs were infected experimentally with both C jejuni (three dogs) and C upsaliensis (three dogs). The challenge strains could be identified in faecal samples from all the dogs, but clinical signs of diarrhoea were seen in only one dog infected with C jejuni. Soft faeces was passed by one dog infected with C upsaliensis. It is concluded that C jejuni/coli or C upsaliensis are either primary pathogens or, after predisposing factors such as virus infections, act as secondary pathogens. It also seems probable that Campylobacter species are present in the intestinal flora of the normal dog.