Studies on the prophylactic effect of feeding probiotics, pathogen-specific colostrum antibodies or egg yolk antibodies in ne newborn calves

The prophylactic efficacy of feeding probiotics, specific egg yolk antibodi es and specific colostrum antibodies on neonatal diarrhoea was investigated in a field trial with calves, grouped (n = 39/40 per group) according to t he following treatments: Group I: feeding no additive; Group II: feeding pr obiotics (5 g powder/day with Bacillus cereus var. toyoi); Group III: feedi ng egg powder (10 g/day with specific egg yolk antibodies against rotavirus , coronavirus and Escherichia coli F5); Group IV: feeding colostrum antibod ies (10 ml/day containing Ig bovine immunoglobulins with specific antibodie s against rotavirus, coronavirus and E. coli antigens); Group V: feeding eg g powder together with probiotics (according to group II and III). The addi tives were given twice daily with the meal from day 2 to day 14 post-natum. The presence of infectious agents was proved in fecal samples of all calve s. Intestinal infections with rotavirus (30.8% of the calves) predominated compared to those with coronavirus (7.1%), E. coli F5 (1.5%) and cryptospor idia (24.2%). In contrast to earlier studies, the manifestation of diarrhoe a did not differ significantly between the five groups. Only the growth rat e of the calves between day 2 and day 14 of life as a measure of their welf are showed treatment-specific differences. The control group (I) showed the lowest body weight gain of about 5.8 kg (SD 5.0), whereas in the treated g roups it averaged 6.3 kg (SD 4.1, p = 0,60; group II), 6.8 kg (SD 4.3, p = 0.36; group III), 6.9 kg (SD 4.7, p = 0.61; group IV) and 7.7 kg (SD 4.9, p = 0.08; group V). Considering only the rotavirus-positive calves the body weight gain of the control group (I) was 3.5 kg (SD 4.8) and of the treated groups was 3.8 kg (SD 3.3, p = 0.65; II), 5.0 kg (SD 3.5, p = 0.54; III), 6.6 kg (SD 4.5, p = 0.05; IV) and 6.1 kg (SD 5.0, p = 0.13; V). Obviously, the feeding of antibodies from colostrum or from egg powder does increase t he mean body weight gain. The feeding of probiotics alone has nearly no eff ect. However, in the combination with specific egg antibodies probiotics se em to have a synergistic effect. In serum from the 198 newborn calves the I gG concentration averaged 4.9 mg/ml serum (SD 3.3). From 93 dams of these c alves a sample of the first colostrum could be obtained showing a mean IgG concentration of 22.0 mg/ml (SD 11.0). IgG levels in the colostrum and in t he serum have been positively correlated (r = 0.37, p < 0.05). Calves with a high intensity of diarrhoea had a significantly (p = 0.01) lower mean IgG serum level (3.7 mg/ml; n = 36; SD 2.5) than calves without diarrhoea (5.6 mg/ml; n = 75; SD 4.0).