Within the scope of this study the IgG-status in 87 new born calves was investigated. All the calves were born in eight different dairy farms around southern Bavaria in Germany.
The procedure of the study was to leave the newborn calves with their dam and allow them to suckle. During this retention period the dam was not milked and the calf was not additionally fed by bottle. The duration of this period was set before the calf was born by assigning it to one of three groups: group I was left 12 hours with their dams, group II 24 hours and group III 48 hours. After that time, the calves were separated from their mother, placed in individual pens and fed by bottle. Blood samples were taken 36-48 hours after birth and additionally at their seventh day of life. The serum was analysed by ELISA according to its IgG-concentration.
The mean serum IgG-concentration at 48 hours in group I was 12.37 mg/ml, in group II 9.87 mg/ml and in group III 16.23 mg/ml. 58.6 % of the calves in group I, 54.6 % in group II and 80 % in group III were provided sufficiently with IgG (> 8 mg/ml). 32 calves (36.8 %) did not reach this critical value, the IgG-concetration in the serum stayed under 8 mg/ml (group I: n = 12, group II: n = 15, group III: n = 5). Half of those showed partial failure of passive transfer (pFPT; serum-IgG 4-8 mg/ml) and the other half showed failure of passive transfer (FPT; serum-IgG < 4 mg/ml).
During the first week of life, the IgG-concentration in the serum of all three groups declined. The mean IgG-concentration of group I went down to 11.34 mg/ml, of group II down to 9.37 mg/ml and of group III down to 14.15 mg/ml.
Time of first suckling correlated significantly negative in all three groups with the serum IgG-concentration.
Suckling behaviour and therefore the intake of first colostrum was influenced by several factors. An interrelation between the course of parturition and the time of first suckling could be determined. The more complicated the parturition was, the later the calf suckled initially. For both female and male calves mean time period of first suckling was 3.2 hours p.n.
The number of the dam’s lactation influenced the serum IgG-concentration in the calves positively. Heifers’calves showed a mean IgG-concentration of 7.48 mg/ml in their serum and calves of cows with more than three lactations showed a significant higher mean IgG-concentration of 14.24 mg/ml.
15 calves out of 87 (17,2 %) came down with diarrhoea, having a mean IgG-concentration of 7.73 mg/ml. Four of them even died during their first week. Those four cases of death belonged to group I and II, showing a mean IgG-concentration of 2.97 mg/ml. None of the calves in group III died during the study period. The calves not suffering from diarrhoea showed a significant higher mean IgG-concentration of 13.53 mg/ml.