Comparison of pasture and concentrate finishing of Holstein Friesian, Aberdeen Angus x Holstein Friesian and Belgian Blue x Holstein Friesian steers.

摘要

Crossbreeding Holstein Friesian dairy cows with both early and late maturing beef breed bulls is common in Ireland. This study concerned the comparison of spring-born Holstein Friesian (HF), Aberdeen Angus x Holstein Friesian (AA) and Belgian Blue x Holstein Friesian (BB) steers slaughtered directly off pasture in the autumn or following a period of concentrate finishing indoors. Male calves (18 per breed type) were reared together until August of their second year when they were assigned to a 3 (breed type) x 3 (finishing strategy) factorial experiment. The three finishing strategies were (i) pasture only for 94 days to slaughter (PE), (ii) concentrate ad libitum indoors for 94 days to slaughter (CE), and (iii) pasture only for 94 days followed by concentrate ad libitum indoors for 98 days to slaughter (PC). For HF, AA, and BB, mean carcass weight, carcass conformation score and carcass fat score values were 275, 284 and 301 (s.e. 5.1) kg, 1.75, 2.42 and 2.89 (s.e. 0.11), and 2.48, 2.89 and 2.17 (s.e. 0.11), respectively. Pasture alone supported live-weight and carcass-weight gains of approximately 800 g/day and 400 g/day, respectively. Live-weight and carcass-weight gains on concentrate ad libitum were approximately 1400 and 870 g/day, respectively. For PE, CE and PC, mean carcass weight, carcass conformation score and carcass fat score values were 244, 287 and 329 (s.e. 5.1) kg, 1.81, 2.56 and 2.69 (s.e. 0.11), and 1.83, 2.71 and 3.01 (s.e. 0.11), respectively. It is concluded that none of the breed types reached an acceptable carcass weight on PE and only HF had acceptable carcass finish. All breed types were acceptably finished on both concentrate finishing strategies.