Pattern of diarrhoea in newborn beef calves in south-west France

A prospective study was carried out on 94 randomly selected beef herds in t he Midi-Pyrenees region in France. The objective was to describe diarrhoea and mortality in beef calves from birth to 30 days of age. Calves (3080) we re followed from December 1995 to April 1996, and a total of 700 visits all owed records of herd management practices, individual data and environmenta l conditions to be collected. The incidence rate for diarrhoea during the n eonatal period was 14.6 %, and varied markedly between herds. Eighteen herd s did not suffer from diarrhoea, while five herds had an incidence of more than 50 %. Results indicate that 52 % of diarrhoea appears during the first week and only 15 % after the second week of life. The greatest risk of dia rrhoea for a calf was during the first and second weeks of life (7.9 and 6. 5 times, respectively). The month of birth was also significantly associate d with morbidity, the highest incidence was observed in December and March ( 17.6 and 23.6 %, respectively). Escherichia coli was isolated from 20.3 % of faecal samples and appeared earlier during the first days of life. Rota virus was frequently isolated (47.4 %) from samples. Coronavirus was positi ve for only 16.5 % but was significantly associated with diarrhoea. Cryptos poridium was less frequent (15.6 %). The global mortality rate was 3.6 % an d was two-times higher in December than in other months. Forty per cent of herds did not exhibit mortality, and 10 % had mortality rates greater than 10 %. This study confirms previously reported data, and with greater precis ion and details on diarrhoea and mortality incidences among herds, age and month of birth in suckling beef calves. (C) Inra/Elsevier, Paris.