The effect of environmental factors on weaning traits of Afrikaner calves
Data from 1142 Afrikaner calves from the herd of stud Afrikaner cattle at the Glen Agricultural Research Institute were used. The calves were the progeny of’ 27 sires and the data collected over a period of 25 years. According to a least square analysis of variance, years, sires, month of birth, sex of calf and mass of dam before calving had statistically significant effects on the weaning traits. Large variations for mass at birth, at 90 days and at weaning and for increase in mass to 90 days and to weaning occurred between years and between sires. Sex of calf was the most significant source of variation studied, bull calves being 8,28% heavier at birth, 8,77% at 90 days and 10,64 % at weaning. There was an increase in weaning traits with increase in mass of dam and although not significant, with the age/parity of the dam. The weaning traits showed an inverse relationship with advancing summer calving season except the birth mass which showed an increase.