[Microbiological study results (bacteriology and electron microscopy) of diarrhea in dog whelps]

Bacteriological examinations of 159 faeces and intestinal contents of dogs with diarrhoea revealed E. coli in 157 specimens. 73 of these samples contained non haemolytic strains, 18 haemolytic isolates, and 66 haemolytic, as well as non haemolytic strains. Klebsiella sp. and Staphylococcus aureus were found in 9 cases, and Salmonella sp. (group B) was isolated once only. By electron microscopy parvovirus could be detected in 19 samples. Ten were positive for coronavirus and one for rotavirus. Morphologically not finally identified coronavirus like and picornavirus like particles were found in 3 cases, respectively. A significant relationship between the occurrence of virus infections and the isolation of certain bacteria species was not found. In 45 E. coli strains virulence factors, such as the heat labile enterotoxin (LT) and the verotoxin (VT), could not be detected, but 31 of these isolates showed different haemagglutination patterns which were still present by 14 of them in the presence of mannose (mannose resistant haemagglutination, MR-HA). These MR-HA inducing E. coli isolates were present more often in parvovirus positive samples (in 6 of 10) than they could be detected in parvovirus negative ones (in 8 of 35), implicating a potential pathogenic role of these E. coli strains for the parvovirus enteritis of dogs.