Heterosis and additive genetic effects for body weight in upgrading Burundi ankole cattle with Sahiwal

الملخص EN

Data on 139 bull calves and 174 heifer calves, representing the Ankole and Sahiwal purebred cattle and their crosses, were used to evaluate the effect of grading up Ankole cattle of Burundi with Sahiwal cattle of Pakistan on live body weights of calves at birth, weaning, 1 year, 2 years and 3 years of age.

Two statistical models were used for analyzing the data; the first included the main effects of genetic group, farm (i.e.

station) and sex, and the second was used to estimate total heterosis and additive genetic effects for live body weights.

The effect of genetic group and sex were highly significant for all weights considered, however, effect of farm (i.e.

station) was only significant (P< 0.001) for both weaning weight and live body weight at 12 months of age.

The additive genetic effect was relatively more important than the total heterosis effect for live weights of weaning, 24 and 36 months of age.

The effect of total heterosis was significant for weights at birth, weaning and 24 months of age and not significant (P> 0.05) for weights at 12 and 36 months of age.

The additive genetic effect was not significant (P> 0.05) for both birth weight and weight at 12 months of age in contrary with the other weights.