Carcass composition of serially slaughtered Friesian, Hereford × Friesian and Charolais × Friesian steers finished on two dietary energy levels

Abstract

The carcass composition of Hereford x Friesian (HE), Friesian (FR) and Charolais x Friesian (CH) steers finished on diets of high (H) and medium (M) dietary metabolizable energy (ME) concentrations and slaughtered at low (L), normal (N) and heavy (W) carcass weights was examined in a 3 x 2 x 3 (no. = 9 per individual treatment) factorial experiment. A pre-finishing slaughter group of nine animals of each breed type was also included, giving a total 189 animals in 21 experimental groups. ME concentrations of the H and M diets which were offered ad libitum were 12-6 and 10-4 MJ/kg dry matter. Target carcass weights for L, N and W were 260, 300 and 340 kg for HE and FR and 260, 320 and 380 kg for CH.Carcass side weights (before tissue separation) of the HE, FR and CH pre-finishing slaughter groups were 90-8, 970 and 101-0 (s.e.d. 3-9) kg. Corresponding tissue proportions were 188, 199 and 200 (s.e.d. 4-3) g/kg bone, 663, 686 and 690 (s.e.d. 5-3) g/kg muscle and 135, 99 and 96 (s.e.d. 5-7) g/kg fat. Main effect side weights of the finished groups were 152-3, 151-4 and 162-2 (s.e.d. 1-4) kg for HE, FR and CH. 158-5 and 152-2 (s.e.d. 1-1) kg for H and M and 131-2, 155-2 and 179-6 (s.e.d. 1-4) kg for L, N and W, respectively. Tissue proportions in the same order were 146, 160 and 157 (s.e.d. 2-0), 149 and 159 (s.e.d. 1-6) and 163, 154 and 146 (s.e.d. 2-0) g/kg bone, 579, 601 and 635 (s.e.d. 5-5), 600 and 610 (s.e.d. 4-5) and 637, 599 and 574 (s.e.d. 5-5) g/kg muscle and 264, 228 and 195 (s.e.d. 6-4), 240 and 219 (s.e.d. 5-2) and 188, 235 and 264 (s.e.d. 6-4) g/kg fat. CH had more (P < 0-001) of their muscle in the pelvic limb and less (P < 0001) in the thorax than HE and FR. HE had more (P < 0-001) of their carcass fat in the subcutaneous depot and less (P < 0-001) in the intermuscular depot than FR and CH. The allometric regression coefficients for the main joint and tissue weights on side weight were <l-0 for both limbs, loin, bone and muscle. Coefficients were >l-0 for the thorax, ribs, flank and fat. The regression coefficients for the main muscles of the pelvic limb and loin and total thoracic limb muscle on total side muscle were <l-0, while the coefficients for the flank, ribs and thorax muscles were >l-0. Similarly the regression coefficients for the bones of the two limbs on total side bone were <10, while the coefficients for the loin, ribs and thorax bones were > 1 0 . It was calculated (for the H diet) that at a carcass weight of 300 kg, HE, FR and CH would have carcass tissue proportions of 576, 600 and 642 g/kg muscle and 261, 227 and 180 g/kg fat. The three breed types would have similar carcass fat contents at carcass weights of 264, 300 and 376 kg for HE, FR and CH, respectively.

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

“…The lowest percentage of meat from fillet was recorded in HE. In agreement with our results, Keane et al (1990) reported lower proportions of muscle in the pelvic limb of CH crosses in comparison with HE crosses.…”

Live animal measurements, carcass composition and plasma hormone and metabolite concentrations in male progeny of sires differing in genetic merit for beef production

“…bone proportions, all three of which are undesirable. The significant negative relationship between sire EPD DMI with carcass meat proportion is consistent with the findings in dairy and late-maturing beef breed cross comparisons, whereby Holstein/Friesian cattle were shown to have higher intake and lower carcass meat proportion than similarly managed Charolais cattle (Keane et al, 1990;McGee et al, 2005). Furthermore, Schenkel et al (2004) reported a significant genetic correlation of 0.24 between feed intake and ultrasonically measured back fat thickness, which is consistent with the increases in scanned fat depth and carcass fat proportion per unit increase in sire EPD DMI observed in the present study.…”

Carcass and meat quality in Brown fattened young bulls: effect of rearing method and slaughter weight

“…It is well known that management practices, such as rearing method, can alter carcass composition through differences in diet composition (Keane et al, 1990;Fiems et al, 2000). Moreover, in our study, that phenomenon is favoured by the relatively low slaughter weight, which can contribute to the persistence of differences in tissue composition derived from the rearing period.…”