The inheritance and interassociation of weaning traits of 1142 Afrikaner calves, the progeny of 27 sires, were studied over a period of 25 years. The estimates of heritability of the weaning traits were as follows: 0,184 ± 0.071 for birth mass; 0.189 ± 0,072 for 90 day mass; 0,051 ± 0.045 for weaning mass; 0.087 ± 0,052 for increase in mass to 90’days; -0,049 ± 0,025 for increase in mass to weaning. The genetic, phenotypic and environmental correlations between the traits studied were generally statistically significant.