Two experiments were conducted to assess the effects of porcine ST (pST) on the responses to a near-ideal blend of AA for pigs from 22 to 60 kg BW. Eighty Hampshire × Yorkshire gilts (40 gilts/experiment) were individually penned and assigned to a 4 × 2 factorial arrangement of treatments, consisting of 4 diets with and without pST injection. A fortified corn-soybean meal basal diet was formula...

To investigate the relationship between chemical composition of meat from the carcass cuts and thewhole carcass, 48 nine-month-old randomly selected ram lambs of Ghezel and Mehraban (24 rams per breed)were used in a trial arranged as a 2 × 2 factorial experiment with two breeds and two feeding levels (high andlow), in a completely randomized design. After 80 days, all animals were slaughtered a...

Estimates of heritabilities and genetic correlations were obtained for weaning weight records of 23,681 crossbred steers and heifers and carcass records from 4,094 crossbred steers using animal models. Carcass traits included hot carcass weight; retail product percentage; fat percentage; bone percentage; ribeye area; adjusted fat thickness; marbling score, Warner-Bratzler shear force and kidney...

Retained heterosis for growth, carcass, and meat traits was estimated in F3 generation castrate male progeny in three composite populations finished on two levels of dietary energy density (2.82 Mcal of ME and 3.07 Mcal of ME and 11.50% CP) and serially slaughtered at four end points at intervals of 20 to 22 d. Breed effects were evaluated in nine parental breeds (Red Poll [R], Hereford [H], An...

Data from 156 Nellore males were used to develop equations for the prediction of retail beef yield and carcass fat content, expressed as kilograms and as a percentage, from live animal and carcass measurements. Longissimus muscle area and backfat and rump fat thickness were measured by ultrasound up to 5 d before slaughter and fasted live weight was determined 1 d before slaughter. The same tra...

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...

An experiment using 81 crossbred swine was conducted to evaluate quantitative and percentage chemical compositional changes of swine from 1.5 kg (birth) to 145 kg body weight. Groups of eight pigs were sacrificed at 1.5, 6.4 and 18 kg, and then at 18 kg increments to 145 kg. Body composit ion was determined by grinding the entire body, minus digesta, partit ioning the carcass from other body co...

Abdominal and subcutaneous fat are regarded as the main sources of waste in the slaughterhouse. Fat stored intramuscularly is regarded a favorite trait related to meat quality. The objective of current study was to estimate genetic parameters for fat deposition in the 3 different parts of body and their relationships with other carcass traits. Traits were recorded for 1,752 females and 1,526 ma...

the effect of ephedrine at 0 (e0c0, n = 10), 8 (e8c0, n = 10) and 10 (e10c0, n = 10) mg per kg metabolic body weight or mixture of ephedrine/caffeine, at doses of 8 mg ephedrine/80 mg caffeine (e8c80, n = 10), or 10 mg ephedrine/100 mg caffeine (e10c100, n = 7), per kg metabolic body weight on body composition of feedlot mehraban ram lambs (8-month-old) was studied. the lambs were fed for 95 da...

Ram lambs, wethers and wethers implanted with Silastic capsules containing crystalline testosterone were placed on test at 14.9 +/- 1.1 kg and evaluated for differences in growth, performance, carcass characteristics and composition. Silastic implants that were able to maintain physiological concentrations of serum testosterone provided appropriate replacement therapy in wethers. Growth rate, e...