Effects of production system intensity on performance, carcass composition and meat quality of beef cattle

Abstract

The objective was to compare animal performance, carcass composition and meat quality of beef cattle reared in three production systems. Thirty six spring-born Charolais×Friesian male cattle were used in a 3 (production systems)×2 (slaughter weights) factorial experiment. The three production systems were (i) young bulls finished on silage plus concentrates and slaughtered at about 19 months of age (Intensive), (ii) steers finished on silage plus concentrates and slaughtered at about 24 months of age (Conventional), and (iii) steers finished off pasture and slaughtered at about 29 months of age (Extensive). The two slaughter weights were 640 kg (Light) and 720 kg (Heavy). Mean daily gains from the start of the treatments at about 7 months of age to slaughter were 1.18, 0.83 and 0.70 (s.e. 0.012) kg for the Intensive, Conventional and Extensive systems, respectively. The Intensive system animals had a higher ( P<0.001) kill-out proportion (568, 541 and 535, s.e. 4.1 g/kg, respectively) and better ( P<0.001) carcass conformation (3.58, 3.00 and 2.83, s.e. 0.125, respectively) than the Conventional and Extensive systems which did not differ in these traits. Other than carcass fat score, all measures of carcass and muscle fatness were higher ( P<0.05) for the Conventional system than for the other two systems which were similar in composition. There were no differences among the systems in muscle shear force or taste panel traits, but the Extensive system animals had poorer ( P<0.01) muscle colour than the other two systems. With increasing slaughter weight, all measures of carcass and muscle fatness increased ( P<0.05), and the taste panel traits of juiciness and tenderness improved ( P<0.05). Carcass output per ha was two-fold and three-fold higher for the Conventional and Intensive systems respectively, than for the Extensive system, but gross margin per animal and per ha was highest for the Extensive system.