Growth from two years to three years and carcass yield and composition were evaluated in nine types of steers produced by mating Angus, Boran and Red Poll bulls to Ankole, Boran and local Zebu cows. One hundred and nine steers were slaughtered at the average age of 3 years and 1 month.
At three years of age, steers by Angus and Red Poll sires were 7% heavier than steers by Boran sires, while progeny of Boran and Ankole dams were 14% heavier than progeny of Zebu dams. Significant hybrid vigour effects on weight-for-age were found.
After adjustment for weight and age at slaughter, linear carcass measurements supported the impression that steers by Angus sires were more compact and blocky than steers by Red Poll and Boran sires and that progeny of Ankole dams were longer in the leg and body than progeny of Boran and Zebu dams. Steers by Red Poll sires appeared to have a higher fat content than steers by Angus and Boran sires on the basis of dissection of a tenth rib sample joint. Progeny of Boran dams had a higher dressing percentage than progeny of Ankole and Zebu dams. Hybrid vigour appeared to have little effect on carcass traits.