Productive performance, meat quality and fatty acid profile of steers finished in confinement or supplemented at pasture

• Published in: Animal (Cambridge, England) Vol. 9; no. 6; pp. 966 - 972
• Main Authors: Patino, H. O., Medeiros, F. S., Pereira, C. H., Swanson, K. C., McManus, C.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.06.2015; Elsevier Limited; Elsevier
• Subjects: Angus; Animal Feed - analysis; Animals; Avena strigosa; beef quality; Body Weight; Brazil; carcass weight; Cattle - growth & development; Cattle - physiology; CLA; color; Confinement; conjugated linoleic acid; cooking; cooking quality; diet; Diet - veterinary; Dietary Supplements; drip loss; energy; fatty acid composition; Fatty Acids - metabolism; finishing; grazing; growth performance; intramuscular fat; Lolium multiflorum; longissimus muscle; Male; marbling; Meat - analysis; Meat - standards; n-3; Nutrition; omega-3 fatty acids; omega-6 fatty acids; pasture; pastures; Research Article; steers; subcutaneous fat; Subcutaneous Fat - metabolism; Brazil; CLA; Confinement; beef quality; n-3; pasture
• ISSN: 1751-7311; 1751-732X; 1751-732X
• DOI: 10.1017/S1751731115000105

Thirty Aberdeen Angus crossbred steers (281±16 kg) were used to test the effect of finishing feeding system on growth performance, meat quality and fatty acid (FA) profile in intramuscular fat. Steers were fed in confinement (forage:concentrate ratio of 50 : 50; DM basis) or with different levels of energy supplementation (0, 0.4, 0.8 and 1.2% BW) at pasture (Avena strigosa Schreb and Lolium multiflorum L.). There were no differences between treatments for ADG (average=1.60 kg/day), hot carcass weight (HCW) (average=229 kg) and subcutaneous fat depth (average=3 mm). Dressing % (P=0.06; tendency) and carcass ADG (P=0.02) linearly increased with level of supplementation for pasture steers. No differences were observed between treatments for tenderness, marbling, pH, color b*, or cooking loss and drip loss in samples of Longissimus dorsi. However L* increased linearly (P=0.05) with level of supplementation. The concentrations of myristic, palmitic, estearic and linoleic FA did not differ among treatments. The concentration of n-3 FA increased (P<0.001) in steers at pasture compared with confinement, but n-6 FA concentrations did not differ between feeding system. Supplementation up to 0.4% BW increase (P<0.001) conjugated linoleic acid (CLA) and linolenic FA concentrations in intramuscular fat when compared with confinement. The level of supplementation on pasture linearly decreased (P<0.001) n-3 and CLA and linearly increased (P=0.001) the n-6 : n-3 ratio. Finishing of steers grazing winter pasture with energy supplementation or in confinement fed a medium-concentrate diet did not affect meat quality (tenderness, marbling, parameter b* on the CIE L*a*b* scale, cooking and drip losses) except for a* and L*. However, intramuscular fat of animals finished at pasture with moderate level of supplementation compared to animals fed in confinement had greater concentration of CLA, linolenic, and n-3, and lower n-6 : n-3 in intramuscular fat.