Effect of management strategy on growth performance, carcass characteristics, fatty acid composition, and palatability attributes in crossbred steers

Abstract

Crossbred steers (n = 136) were used to evaluate the effect of management strategy on growth performance, carcass characteristics, and fatty acid composition and palatability attributes of beef. Management strategies included: (1) high grain (75% high moisture corn) finishing (HG), or (2) backgrounding with restricted feeding of an alfalfa silage ration for 112 d, followed by HG until slaughter (BKG). Steers were slaughtered at 8–10 mm ultrasound backfat. Backgrounding increased (P < 0.001) days on feed and decreased (P < 0.01) days on grain, average daily gain and longissimus muscle area compared with the HG regime. Slaughter weight, intramuscular fat content, and marbling score were unaffected (P > 0.10) by management strategy. Longissimus muscle palatability attributes and shear force did not differ (P > 0.10) between management strategies, whereas BKG increased (P < 0.03) softness, overall tenderness, chewiness, and rate of breakdown scores, and decreased (P < 0.09) juiciness scores in semitendinosus muscle. Backgrounding increased (P < 0.05) conjugated linoleic acid (CLA), total monounsaturated fatty acids, and 1193 polyunsaturated fatty acid (PUFA), and decreased (P < 0.05) total saturated fatty acids (SFA), and 1196 PUFA content of beef. While the change in quantitative and qualitative fatty acid composition of beef is in line with current dietary recommendations for humans, the magnitude of these changes was minimal. Key words: Beef cattle, diets, carcass composition, fatty acids, longissimus muscle, palatability attributes