CHARACTERIZATION OF DIFFERENT BIOLOGICAL TYPES OF STEERS (CYCLE-IV) -WHOLESALE, SUBPRIMAL, AND RETAIL PRODUCT YIELDS

Carcass cut-out yields of 888 steers obtained from mating Hereford and Angus cows to Hereford or Angus (HA), Charolais (Ch), Gelbvieh (Gb), Pinzgauer (Pt), Shorthorn (Sh), Galloway (Gw), Longhorn (Lh), Nellore (Ne), Piedmontese (Pm), and Salers (Sa) sires were compared. Data were evaluated at constant age (426 d), carcass weight (324 kg), fat thick ness (1.2 cm), fat trim percentage (23%), and marbling (Small(00)) end points. Piedmontese-sired steers excelled in total retail product and fat trim percentages at all slaughter end points except at the 23% fa t trim end point. At an age end point, percentage of retail product wa s greater in steers sired by Continental European breeds (Gb, Ch, Sa, Pt; 63.3 to 65.5% at 0 cm trim) than in steers sired by British breeds (Sh, HA; 60.1 to 61.0%). Piedmontese-sired steers, which were expecte d to carry one copy of a major gene for muscle hypertrophy, had the hi ghest (P < .05) retail product yields at an age end point (69.7%). At an age end point, although carcass weights were significantly heavier( P < .05) for Charolais-sired steers than for Piedmontese-sired steers, lean growth rate, as reflected by totally trimmed retail product at 4 26 d, was similar (P > .05) for Piedmontese and Charolaissired steers. Differences among sire breeds were small for retail product percentag e at marbling, fat thickness, and fat trim end points. Ranking of sire breeds for age-constant weight of retail product was as follows: Ch, Pm, Gb, Sa, Ne, Pt, HA, Sh, Gw, and Lh. Sire breed differences in whol esale and subprimal cut yields were similar to total retail product di fferences. Piedmontese-sired steers produced the most muscular, leanes t, and highest-yielding carcasses, and HA-and Sh-sired steers produced the fattest, lowest-yielding carcasses.