A comparison for live weight and carcass production of Charolais, Hereford and Friesian steer progeny from Friesian cows finished on two energy levels and serially slaughtered

Abstract

One hundred and sixty-two spring born steers comprising 54 Charolais × Friesian (CH), 54 Hereford × Friesian (HE) and 54 Friesians (FR) were reared together from shortly after birth until the end of their second grazing season at a mean age of 573 days. The animals were then blocked on weight within genotype, housed in a slatted shed and allocated to either a high (12·6 MJ metabolizable energy (ME) per kg) or a medium (10·4 MJ ME per kg) energy diet offered ad libitum until slaughter at one of three target carcass weights · light (260 kg (HE, FR and CH)), normal (300 kg (HE and FR) and 320 kg (CH)) or heavy (340 kg (HE and FR) and 380 kg (CH)) to give a 3 (breed type) · 2 (energy level) · 3 (slaughter weight) factorial arrangement during the finishing winter. The trial was repeated in 3 years consecutively.CH were significantly heavier than HE at all times up to 18 months of age when they were 43 kg heavier, at which stage they were also 24 kg heavier than FR. CH grew significantly faster at pasture than HE in both seasons and faster than FR in the second season. HE had the best daily gain in the finishing period.Overall slaughter weights per day of age, carcass weights per day of age and carcass weights of CH, HE and FR were 812, 771 and 761 (s.e. 9·2) g, 448, 418 and 405 (s.e. 4·8) g and 318. 299 and 298 (s.e. 2·2) kg, respectively. CH had significantly better killing-out proportions (lOg/kg) than HE which in turn were 10 g/kg better than FR. CH and FR had similar carcass length, carcass depth, leg length and leg widths and both were significantly larger than HE. CH had significantly larger longissimus dorsi areas than either HE or FR (80·9 v. 67·0 and 66·4 cm-); they also had significantly better conformation scores than HE which in turn were significantly better than FR.Increasing the energy level during the finishing period increased daily gain by proportionately 0·52 (1089 v. 684 g/day), reduced slaughter age by 51 days (711 v. 762 days) and significantly increased killing-out proportion (551 v. 534 g/kg) and conformation score (4·86 v. 4·64). Offal as a proportion of empty live weight tended to be higher for FR than for HE or CH, the exception being the hide, which was significantly lower for FR.

Using machine learning procedures to ascertain the influence of beef carcass profiles on carcass conformation scores

“…(Quinlan, 1993). The linear behaviour of conformation grading in standard carcasses is consistent with previous information reporting that the conformation score is expected to increase with age and carcass weight (Kempster et al, 1988;More O'Ferral & Keane, 1990). However, the linearity of the behaviour assessed in the training sets analysed here is more likely to be dependent on the design of a dataset that focused on avoiding most of the sources of heterogeneity of the products to be assessed and of the differences between assessment sessions , in our case different fattening methods and multiple classifiers.…”

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

“…The authors also reported that the carcasses from British sire breeds tended to have lower dressing percentage than Continental Europe sire breeds at common fat thickness and fat trim percent endpoints. The low dressing percentage of HE bulls found in the present study can also be explained by their low average slaughter weight; it was previously established that this trait increased with increasing slaughter weight (Kempster et al, 1988;More O'Ferrall and Keane, 1990).…”

A comparison of the growth and carcass traits between dairy and dairy × beef breed crossbred heifers reared for beef production

“…The higher growth capacity of the dairy × late maturing beef breed crosses compared to the pure dairy breeds has been demonstrated in numerous studies (e.g., Roux et al, 1987;More O'Ferrall and Keane, 1990). For example, Roux et al (1987) observed that the crossbred Friesian × Charolais heifers showed improved growth, resulting in heavier and leaner carcasses at the same age compared to purebred Friesian heifers.…”