Effects of breed and dietary energy content within breed on growth performance, carcass and chemical composition and beef quality in Hereford and Simmental steers

Abstract

. 1998. Effects of breed and dietary energy content within breed on growth performance, carcass and chemical composition and beef quality in Hereford and Simmental steers. Can. J. Anim. Sci. 78: 533-541. Forty-eight Hereford and 60 Simmental steers were used to evaluate breed differences as affected by dietary energy content on growth performance, carcass and chemical composition, and beef quality. Diets were based on corn silage, alfalfa haylage, whole corn, and SBM and were formulated to provide 2.52 to 2.81 Mcal kg -1 ME and 11.7 to 12.6% protein in the growing phase and 2.69 to 2.86 Mcal kg -1 ME and 9.7 to 10.4% protein in the finishing phase. Low-and high-energy diets were formulated for each breed with the high-energy diet for Hereford serving as the low-energy diet for Simmental. Steers were slaughtered after attaining 8 to 10 mm backfat determined by ultrasound. Higher energy diets increased (P < 0.09) average daily gain (ADG) and feed efficiency within both breeds. Hereford gained more rapidly (P = 0.074) and were more (P = 0.001) efficient in converting feed to gain than Simmental. High-energy diets decreased (P = 0.001) days on feed for both breeds and increased (P = 0.001) carcass weights for Simmental. Otherwise, carcass and chemical composition were generally unaffected by dietary energy content. Simmental were heavier (P = 0.001) and leaner (P = 0.001) than Hereford while marbling classification and intramuscular fat content were similar (P > 0.10) between breeds. While shear force decreased (P = 0.043) feeding the low-energy diet to Simmental, other shear and palatability attributes were unaffected by dietary energy content or breed. Altering dietary energy content for Hereford and Simmental influenced growth performance without affecting carcass and chemical composition and beef quality. Simmental ont été utilisés pour évaluer les différences raciales quant à l'influence du contenu énergétique de l'aliment sur les performances de croissance, sur la composition de carcasse et la composition chimique et sur la qualité de la viande. Les aliments étaient faits d'ensilage de maïs, d'ensilage de luzerne mi-fané, de maïs-grain entier et de tourteau de soja, formulés de façon à fournir de 2,52 à 2,81 Mcal kg -1 de EM et de 11,7 à 12,6 % de protéines dans la phase de croissance et de 2,69 à 2,86 Mcal kg -1 EM et de 9,7 à 10,4 % de protéine dans la phase de finition. Chaque race était exposée à un régime à haute et un à basse teneur énergétique, le régime à haute teneur utilisé pour les Hereford servant de régime à basse teneur pour les Simmental. Les bouvillons étaient abattus lorsque l'épaisseur du gras de couverture, mesurée aux ultrasons, était de 8 à 10 mm. Dans chaque race, les aliments à fort contenu énergétique donnaient lieu à un accroissement (P < 0,09) du GMQ et de l'efficacité alimentaire. Les Hereford grandissaient plus rapidement (P = 0,74) et valorisaient mieux (P = 0,01) leurs aliments que les Simmental. En outre, la durée de l'engraissement était plus courte (P = 0,001) chez les deux rac...

Effect of breed on growth performance and carcass composition of Aberdeen Angus, Charolais,Herefordand Simmental bulls

“…HE had ) differ significantly (P < 0.05) + not examined due to presence of breed by year interaction 1 evaluated only in year 2 (Scale 1 = S (best) to 6 = P (poorest)) 2 evaluated only in year 2 (Scale 1 (leanest) to 5 (fattest)) *adjusted means (slaughter weight used as a covariate) **LS means (no covariate used) the lowest, SI intermediate, and AA and CH bulls the highest percentage of bones and tendons. Similar to the present study, no significant differences were found between bone yields of SI and HE bulls and steers (Mandell et al, 1997(Mandell et al, , 1998 and SI and Red Angus steers (Laborde et al, 2001). Meat to bones and tendons ratios reflected the relationships between the two components in carcasses from different groups.…”

“…Similarly to our findings, SI and CH steers had higher average daily gains than all the other compared breed groups (including AA and HE) after a constant time on feed (Gregory et al, 1991(Gregory et al, , 1994a. On the contrary, medium framed HE steers gained more than large framed SI steers when fed to a common backfat endpoint presumably due to a shorter time on feed and higher efficiency for maintenance and gain (Mandell et al, 1998). Similarly, Chambaz et al (2001) reported higher gains of AA compared to SI and CH slaughtered at a common target level of intramuscular fat also probably resulting from lower age at slaughter and days of fattening in AA.…”

“…Similarly, carcasses from Continental European (including CH ands SI) sire breeds had heavier weights and percentages of retail product at constant carcass weight than carcasses from British sire breeds (AA and HE) (Wheeler et al, 2005). Higher lean yields were also recorded in carcasses from purebred SI compared to HE steers (Mandell et al, 1998) and from purebred SI compared to Red Angus steers (Laborde et al, 2001). …”

“…Growth performance, carcass composition and beef quality of purebred Hereford and Simmental steers fed two diets with different energy contents and slaughtered at similar backfat thickness were compared by Mandell et al (1998). Hereford gained more rapidly and more efficiently in this study while Simmental had heavier and leaner carcasses.…”

Performance and carcass quality of Czech Fleckvieh, Charolais and Charolais × Czech Fleckvieh bulls fed diets based on different types of silages

“…In agreement with our study, the average live weight gain and feed efficiency were positively affected by a higher dietary energy concentration in Simmental bulls (Sami et al, 2004). Also, increasing the dietary energy content improved daily live weight gains and feed efficiency in Simmental and Hereford steers (Mandell et al, 1998). Replacing grass silage with maize silage improved the growth rate and feed conversion efficiency of Simmental × Holstein steers, as reported by Juniper et al (2005).…”