Evaluation of Qazaq Aqbas bulls' feed efficiency traits for breeding goals: A case study

The Qazaq Aqbas beef breed is the most important in Kazakhstan. The breed is very well adapted to the harsh conditions in Central Asia. Other more productive breeds need additional costs to ensure their survival and productivity. However, their production levels are lower than other beef breeds globally. It may be possible to improve this by selecting bulls that have greater feed efficiency. This case study reports analyses of feed intakes and weight gains by this breed on farms in Kazakhstan. Twenty-nine bulls were selected, and fed using the GrowSafe system that measures and records intakes and weights. The ranking by Residual feed intakes (RFI) identified those bulls that were most efficient regarding weight gains compared to their feed intakes. While there was a positive correlation between ADG and DMI (P = 0.011), there was no correlation between RFI and ADG. Relying simply on weight gains for breeding decisions is therefore not supported by this evidence. The daily feed intakes of the breed recorded (11.03 kg/d) were similar to those of non-native popular beef breeds, while the weight gains (0.95 kg/d) were smaller. Therefore, the selection for breeding of beef bulls could focus on feed efficiency and not only feed intakes or daily weight gains.