[Campylobacter as the cause of diarrhea in calves].

The modified Preston medium allows the isolation of C. jejuni, C. coli and C. fetus subsp. fetus from intestinal samples of calves at an incubation temperature of 37 degrees C. In the first series of investigation, Campylobacter excretion in calves (n = 7) was followed up to the age of 4 months. In the first 4 days of life, these bacteria could not be detected in any of the animals. Thereafter first C. coli we found in all calves. In 4 animals, only strains of this species were isolated during the whole investigation period. In 3 animals C. fetus subsp. fetus could be detected repeatedly, however C. coli and sometimes C. jejuni were found, too. In the second series of investigation, isolation of Campylobacter from different parts of the gastrointestinal tract or organs was successful in 19 out of 25 diarrhoeal, moribund calves. 16 out of 19 positive animals harboured large amounts of these gramnegative bacteria in the distal jejunum and ileum. In 10 animals out of these 16, the germ colonized also the proximal jejunum and abomasum. From 6 calves, C. fetus subsp. fetus was isolated, and C. jejuni from 7 calves. C. coli was relatively rare. From the lymph nodes of the proximal and distal jejunum, Campylobacter (exclusively C. jejuni) were isolated from 5 animals. Due to the Campylobacter presence in the small intestine of diarrhoeal calves, a contribution of this bacteria within the pathogenesis of calf diarrhoea is possible. Final evaluation of their pathogenesis importance is only positive by means of virulence tests.