Sixty rabbits from the 23rd generation (group S) of a line selected for growth rate were compared to sixty rabbits from the 7th generation of the same line (group C) to study possible relevant changes in carcass composition and meat quality due to the selection and the consequent decrease in degree of maturity at slaughter weight (2000g). The only relevant changes in carcass composition were an...

Although carcass trait selection programs have primarily focused on carcass marbling (quality grade), recent changes in the North American beef industry will very likely increase the economic importance of carcass composition (yield grade). Ultrasound technology is a valuable tool in these efforts. This review summarizes recent research pertaining to the role of ultrasound in improving carcass ...

The aim of this study was to evaluate the relationship between slaughter age and slaughter-carcass characteristics in 2 quail lines. With this aim, a Japanese quail flock subjected to mass selection to increase BW for 4 generations and a control flock that randomly mated for 4 generations were used. Birds of both lines were slaughtered at 4, 5, 6, 7, and 8 wk of age. Weights of carcass, breast,...

________________________________________________________________________________ Abstract The effect of sex and the supplementation of the prebiotic, mannan oligosaccharides (MOS), the acidifier, calcium propionate (CPr) or their combination in the feed of Japanese quail (Coturnix japonica) on their performance and carcass quality was examined in this experimentation. Three hundred, 1-day old J...

Artificial selection in closed populations can fix or differentiate alternative alleles of loci associated with selected traits. Two closed chicken populations, A and B, originating from Jiuwu, a Chinese native breed, were bred for more than 10 generations. We compared progeny from reciprocal crosses (AB and BA) under free range (trial 1) and cage and pen (trial 2) systems. Traits measured incl...

Every 3 mo for a 2-yr period, two weaned Holstein steer calves (94.5 kg) were randomly assigned to each of four slaughter age groups (3, 6, 9, and 12 mo). Urea dilution was performed before slaughter, and urea space (US) was calculated as total volume and as a percentage of body weight (BW) and empty body weight (EBW). The relationships between US (kg, % EBW and % BW), BW, and EBW and carcass s...

To evaluate different methods of estimating bovine carcass composition, seventy yearling bulls of the "Asturiana de los Valles" beef breed were slaughtered and their carcass composition estimated by a commercial dissection of the right half-carcass and by tissular dissection of the 6th and 10th rib of the left half-carcass. Correlation and regression analyses were used to identify the most accu...

and Implications Variance parameters including heritabilities, genetic and residual correlations are required for national cattle evaluation. There are huge amounts of data available for estimating such variance parameters for growth traits, but much less data is available for carcass traits. In this study, heritabilities and genetic correlations were estimated using restricted maximum likeliho...