Abstract

Traditionally, British breeds have been the main source of beef produced in New Zealand. Recently the use of dairy breeds has increased. This experiment evaluates the growth rate and carcass characteristics of steers (n=64) born to straightbred Angus (AA), Angus-cross-Holstein Friesian (AF), Angus-cross-Jersey (AJ) or Angus-cross-Kiwicross (AK) dams, and sired by Angus (A) or Simmental (S) bulls. This created eight crossbred treatments: A-AA (n=10), A-AF (n=9), A-AJ (n=10), A-AK (n=5), S-AA (n=11), S-AF (n=3), S-AJ (n=11) and S-AK (n=5). Live weight between 329 days of age and slaughter, and ultrasoundderived and slaughter-day carcass characteristics were measured. At 400 and 600 days of age, respectively, Simmental-sired steers were 22 kg and 37 kg heavier than Angus-sired steers (P<0.05). All steers had a similar intramuscular fat percentage (P>0.05). Simmental-sired steers had greater eye-muscle area than Angus-sired steers (P<0.05). Simmental-sired steers had heavier and longer carcasses, and greater dressing-out percentages than Angus-sired steers (P<0.05). Simmental sires produced fast-growing progeny with heavier carcasses than Angus sires for all dam lines. Angus-cross-dairy cows produced steer progeny with similar carcass characteristics to those from Angus cows bred with beef bulls.

KJD, Collier, RE Hickson, NM Schreurs, NP Martin, PR Kenyon, and ST Morris

Proceedings of the New Zealand Society of Animal Production, Volume 75, Dunedin, 15-19, 2015