Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 29, 2001
Publication Date: N/A
Interpretive Summary: The beef industry is under increasing pressure to improve the consistency of beef by reducing fat while improving palatability of beef products. One way to accomplish this is to utilize breeds of cattle that will more closely meet product targets. This project was designed to determine differences among beef breeds for carcass traits and ribeye steak eating quality by evaluating carcasses of steers produced by mating Hereford, Angus, and MARC III cows to Hereford, Angus, Brahman, Boran, Tuli, Piedmontese, or Belgian Blue bulls. Piedmontese and Belgian Blue steers produced the leanest, heaviest muscled carcasses. Hereford and Angus cross carcasses were the fattest and least muscular. Marbling scores were highest for Hereford x Angus and Tuli and lowest for Brahman, Belgian Blue, and Piedmontese cross carcasses. Hereford x Angus, Tuli, and Piedmontese cross steers produced the most tender meat and Brahman and Boran cross steers produced the least tender meat. Because of the large variation within and among breeds for most traits, significant genetic change could result from selection both among and within breeds. Carcasses from Belgian Blue- and Piedmontese-sired steers provided the most desirable combination of yield grade and ribeye steak palatability, but carcasses from Hereford x Angus cross steers provided the most desirable combination of quality grade and ribeye steak palatability. Tuli appear to provide heat tolerance without a detrimental effect on meat tenderness.
Technical Abstract: Carcass and longissimus thoracis palatability traits from 817 F1 steers obtained from mating Hereford, Angus, and MARC III cows to Hereford or Angus (HA), Tuli (Tu), Boran (Bo), Brahman (Br), Piedmontese (Pm), or Belgian Blue (BB) sires were compared. Data were adjusted to constant age (444 d), carcass weight (333 kg), fat thickness (1.0 cm), fat trim percentage (21%), and marbling (Small00) end points. At a constant age of 444 d, carcasses from BB- and HA-sired steers were heaviest (P < .05) and carcasses from Bo- and Tu-sired steers were lightest (P < .05). USDA numerical yield grades were lowest (P < .05) for carcasses from Pm- and BB-sired steers and highest (P < .05) for carcasses from HA- and Br-sired steers. Marbling scores were highest (P < .05) for carcasses from HA- and Tu-sired steers and lowest (P < .05) for carcasses from Br-, BB-, and Pm-sired steers. Longissimus thoracis from carcasses of HA-, Pm-, and Tu-sired steers had the lowest (P < .05) 14 d postmortem Warner-Bratzler shear force values. Carcasses from HA-sired steers had longissimus thoracis with the highest (P < .05) tenderness ratings at 7 d postmortem. Longissimus thoracis from carcasses of Br- and Bo-sired steers had the highest (P < .05) Warner-Bratzler shear forces and the lowest (P < .05) tenderness ratings at 7 d postmortem. Carcasses from BB- and Pm-sired steers provided the most desirable combination of yield grade and longissimus palatability, but carcasses from HA cross steers provided the most desirable combination of quality grade and longissimus palatability. Tuli appears to provide heat tolerance without a detrimental effect on meat tenderness.