Seventeen Holstein newborn calves were used with the objective of evaluating the influence of milk replacer volume in the pattern of pathogens causing neonatal diarrhea. The animals were divided into two groups, 8 calves in group 1 and 9 calves in group 2. The calves were fed twice daily in the total of 4 liters of milk replacer to group 1 and 6 liters to group 2. From the 1st day of arrival of the calves feces were evaluated daily after the morning feeding for the classification of diarrheal feces or without diarrhea. The first day of diarrhea until the seventh day, feces were collected on alternate days (1st, 3rd, 5th and 7th day) directly from the rectum to evaluate enteropathogens. Were collected blood samples from calves with five days of age for determination of total protein. The average total protein was 6.33 and 6.21g/dL in groups 1 and 2, respectively. The group 2 tended (p<0.1) higher consumption of milk replacer during the study period. The volume of milk replacer did not influenced the incidence of diarrhea and the frequency of positive samples for each etiologic agent between the two groups (p>0.05). Also, there was no difference (p>0.05) on the pattern of the frequency of positive samples for evaluated pathogens. The frequency of pathogens in the samples was 100 and 75% for Cryptosporidium, 28.5 and 43.7% for Salmonella spp., 28.5 and 15.6% for E. coli pathotypes, 3.5 and 6.2% for Rotavirus and 10.7 and 9.4% for Giardia in groups 1 and 2, respectively. Serotypes of Salmonella infantis and muenster were found. The isolated pathotypes of E. coli isolates were classified as Escherichia coli enteropathogenic, enterotoxigenic and Shiga-toxin-producing 1 and 2. Associations between Cryptosporidium spp. and E. coli pathotypes, and between Cryptosporidium spp. and Salmonella spp. were found in 30% of the samples in group 1 and in 45.5% in group 2, respectively. Our results showed that the different volumes of milk replacer did not influence the incidence and etiology of neonatal diahrrea. Longitudinal evaluation of enteropathogens during patency demonstrated that the association between the etiologic agents starts from the first day of disease. This result highlighted the great importance of the infection by Cryptosporidium spp. which was present in every moments and animals evaluated.
Diarrhea; calves; enteropathogens; milkreplacer; feeding strategies
