The Influence of Sire and Dam Genotype on Pre and Post Weaning Weight of Horro (Zebu) and Their Crosses with Holstein Friesian and Jersey cattle

The influence of sire and dam genotypes on birth weight (BW), weaning weight (WW), pre-weaning average daily gain (DG), post-weaning average daily gain (PDG) and one year weight (YW) in calves of Horro and crosses of these indigenous with Bos Taurus (Holestian Friesian and Jersey) were investigated from data collected from Bako Agricultural Research center during the year 1980-2008. Least squares means were analysed using General Linear Model (GLM) of Statistical Analyses System (SAS). Sire and dam genotype, sex, dam age, parity and Julian birth date were considered in the fixed effects model with addition of age at weight measurement as a covariate. Calves sired by pure Holstein Friesian bulls 3.8kg heavier than the sired by Horro bulls and 1.2 kg heavier the calves sired by Holestian Friesian-Horro at birth. The no difference in BW of calves by the Jersey, Jersey-Horro and Horro bulls. The influence of dam genotypes on the pre and post weaning weight of calves was highly significant (P<0.05). Holestian Friesian-Horro dams produced the heavier (P<0.05) calves at weaning than Horro and Jersey- Horro dams, whereas at one year weight no significant difference between Horro and Holestian Friesian-Horro dams. The result also indicated that pre and post weaning weight of the calves sired by pure Holestian Friesian bulls were superior (P<0.05) to others. Keywords: Dam genotype, Holstein Friesian, Horro, Jersey, sire genotype