PROPORTIONAL MORBIDITY RATES OF ENTEROPATHOGENS AMONG DIARRHEIC DAIRYCALVES IN CENTRAL SPAIN

Faecal samples from 218 diarrheic dairy calves in 65 dairy herds, sele cted by convenience, were screened for the presence of rotavirus, coro navirus, Cryptosporidium spp., F5(+) Escherichia coli and Salmonella s pp. Animals surveyed were from 1 to 30 days old. Cryptosporidium and r otavirus were the most commonly detected agents (52.3% and 42.7% of th e samples positive, respectively). F5(+) E. coli was detected in the f aeces of 11.9% of the calves and bovine coronavirus was detected in th e faeces of 7.3% of the calves. Salmonella spp. was only found in the faeces of two calves (0.9%). Mixed infections with two or more agents occurred in 28% of the calves. Concurrent infection of rotavirus and C ryptosporidium was found in 21.6% of the calves. Two tests were used f or the detection of rotavirus (a commercial ELISA and PAGE), F5(+) E. coli (ELISA and bacterial culture) and Cryptosporidium (ELISA and micr oscopy). The validity of the commercial ELISA for the detection of rot avirus, F5(+) E. coli and Cryptosporidium in faeces from diarrheic cal ves was evaluated using PAGE, bacterial culture and microscopy as gold standard, respectively. The ELISA showed a very low sensitivity (28.6 %) for the detection of F5(+) E. coli compared to bacterial culture. ( C) 1998 Elsevier Science B.V.