Comparisons among Two-Breed Cross Cow Groups. II. Feedlot and Carcass Performance of Three-Breed Cross Calves2

Abstract

Feedlot and carcass data were collected over a 7-yr period on 1,506 three-breed cross steers and heifers produced by Hereford × Angus (HA), Angus × Hereford (AH), Simmental × Angus (SA), Simmental × Hereford (SH), Brown Swiss × Angus (BA), Brown Swiss × Hereford (BH), Jersey × Angus (JA) and Jersey × Hereford (JH) cows mated to Charolais, Brahman, Limousin and Gelbvieh bulls. Calves entered the feedlot each year at weaning and were fed to an anticipated low Choice carcass grade. Longissimus muscle marbling and carcass grade did not vary significantly among crossbred-dam groups. Stated differences were significant. Compared with calves from HA and AH cows (averaged 216 kg), initial weights were heavier for calves from S-, B- and J-cross cows by 10, 12 and 6%, respectively. Compared with the average slaughter weight of calves from HA and AH cows (500 kg), calves from S- and B-cross cows were 9 and 6% heavier, respectively, and calves from J-cross cows averaged 4% lighter. For the entire feeding period, average daily gains for calves from HA, AH, S- and B-cross cows (averaged 1,147 g/d) exceeded that of calves from J-cross cows by 8%. Daily gains of calves from S-cross cows exceeded gains of calves from HA cows by 4%. Calves from S-cross, BH and HA cows were on feed an average of 261 d, followed by calves from BA, AH and JH (averaged 248 d) and JA (237 d). Feed intake was measured on a pen basis (calves were penned by crossbred-cow group, sire breed and sex) for the last 5 yr of the study. Feed conversion favored calves from HA and AH cows (7.43 kg feed/kg gain) over calves from SA, BA and JH cows by an average of 5% and calves from JA cows by 7%. Compared with carcass weights for calves from HA and AH cows (averaged 319 kg), carcasses of calves from S-, B- and J-cross cows, respectively, averaged 9% heavier, 6% heavier and 5% lighter. Carcass weight per day of age was similar for calves from S- and B-crosses (averaged 738 g/d) and exceeded the average of calves from HA and AH cows by 6%. External fat thickness of calves from HA and AH cows (averaged 1.51 cm) was .24 cm greater than for calves from S-cross and JA cows and .34 cm greater than for calves from BH and JH cows. The average longissimus muscle area of calves from HA and AH cows (81.8 cm2) was 4.8 cm2 smaller than that of calves from S-cross cows, but 3.7 cm2 larger than that of calves from JA cows. Dressing percentage was greater for calves from AH, SH and BH cows (64.3%) than for calves from HA and J-cross cows (averaged 63.4%).