Resumen

JORGE, J.R.V. et al. Protected fat and performance, carcass and meat chemical composition in holstein frisian steers. Arch. zootec. [online]. 2009, vol.58, n.223, pp.371-382. ISSN 1885-4494.

The objective of the present work was to evaluate intake, performance, carcass characteristics and chemical meat composition of Holstein steers. Forty eight castrated steers, with an average age of 24 months and an initial average weight of 405 kg, were used; they were distributed into a completely randomized set, with (WFR) or without (WTFR) fat inclusion in the diet and three slaughter weights (450, 510 and 600 kg), with eight repetitions. The inclusion of fat in the diet caused an effect (p<0.05) on the intake of dry matter, being 14.6 kg/day for WTFR and 13.5 kg/ day for WFR. The slaughter weights did not influence (p>0.05) the intake of nutrients. The daily average gain (1.12 kg/day), the feed conversation ratio (12.8 kg/kg gain), dressing percentage (47.8%), back fat thickness (4.82 mm), rib eye area (109.5 cm²) and rib eye area/100 kg of muscle (43.3 cm²/100 kg) were not affected by the fat inclusion or by the slaughter weights. Chilling loss was higher at slaughter at 450 kg as compared with the others (510 and 600 kg). There was no effect (p<0.05) of the fat inclusion on the contents of protein (22.76%), moisture (73.95%), fat (2.50%), and cholesterol (57.58 mg/100 g muscle).

Palabras clave : Cholesterol; Cottonseed; Tenderness; Weight gain.

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