ABSTRACT
This study was carried out in two dairy farms in Beni-Suef governorate on a total of 67 calves from birth till weaning age. The calves in farm [I] isolated from their dams after five days postpartum while in farm [II] the calves kept with their dams. Oral and social behavioural patterns of these calves were recorded. Calf performance as well as average daily gain in body weight, girth, height and length were measured till weaning age. Moreover IgG and IgM were estimated in the sera of newly born calves during pre and post colostrol feeding. These parameters were also estimated in the colostrum. Results revealed an increase in oral behavioural patterns with the advance of age in calves of both farms. The percentage of time in rumination in calves at the age of 6 weeks was significantly higher [20.20%] in farm I than in farm II [14.62%]. Social behaviour under natural rearing system [farm II] was improved to a greater extent than under artifical rearing [farm I]. The obtained results showed an increase in calf birth weight in farm [I] [30.68 Kg] than those in farm [II] [27.70 Kg], while there was no significant difference in the average daily weight gain between the two farms. Moreover, the other calf body measurements showed no significant differences between the two farms. The levels of IgG in farm [I and II] at birth amounted to 1.74 and 1.96 mg/ml respectively. After 24 hours post colostrol feeding these values increased to 35.47 and 39.52 mg/ml. On the other hand, the levels of IgM in farm [I and 11] at birth were 0.18 and 0.14 mg/ml respectively, and increased to 2.69 and 2.73 mg/ml 24 hours after post colostral feeding In the colostrum, the levels of IgG in farm [I] und [II] [21.95 and 21.24 mg/ml] were higher than those of IgM [2.48 and 2.42 mg/ml]. It was concluded that cohabitation of the calves with their dams from birth till weaning favour the calf welfare, improving the social behaviour and immune status which reflects the high performance