Serum and pituitary growth hormone (GH) concentrations were measured by radioimmunoassay in 69 Duroc and 70 Yorkshire swine genetically selected for at least 14 generations for either high backfat (high line) or low backfat (low line). For both breeds, the high line pigs had lower serum GH at weaning (P<.05) and lower serum and pitui tary GH at slaughter (P<.01) than the unselected control line...

last rib backfat thickness, broken vertebrae, or scores for stomach ulcers (P > 0.21). Also, deletions of VTM premixes did not affect these same measurements (P > 0.22). However, RAC decreased (P < 0.01) backfat thickness by 8% and tended to decrease scores for stomach ulcers (P < 0.06). In conclusion, there were no interactions to suggest that the effects of RAC on growth performance and carca...

A total of 144 barrows and gilts (initial BW = 44 kg) were used in an 82-d experiment to evaluate the effects of dietary fat source and duration of feeding fat on growth performance, carcass characteristics, and carcass fat quality. Dietary treatments were a corn-soybean meal control diet with no added fat and a 2 × 4 factorial arrangement of treatments with 5% choice white grease (CWG) or soyb...

Records on 361,300 Yorkshire, 154,833 Duroc, 99,311 Hampshire, and 71,097 Landrace pigs collected between 1985 and 1999 in herds on the National Swine Registry STAGES program were used to estimate additive genetic (animal), common environmental (litter) and residual variances and covariances for lean growth rate, days to 113 kg, backfat, and loineye area. Analysis was by the REMLf90 program of ...

PIT1, a member of the POU-domain family of genes, is a positive regulatory factor of growth hormone, prolactin, and thyrotroph-stimulating hormone /3 in several mammals. Therefore, PITl was chosen as a candidate gene to investigate its association with growth and carcass traits in pigs. The five Iowa State University referencehesource threegeneration families consisting of crosses of Meishan x ...

Two hundred and ninety-four pigs were used to assess the effect of two ingredients (Lupinus albus (albus lupins) or a combination of calcium chloride and sodium tri-polyphosphate (mineral salts)) on growth performance, body composition and objective meat quality of pigs immunized against gonadotrophin releasing factor (immunocastrates) and entire male pigs in the late finishing phase. Pigs fed ...

Records on 65,536 Landrace pigs collected between 1985 and 1999 in herds on the National Swine Registry STAGES program were used to estimate additive genetic (animal), common environmental (litter), and residual variances and covariances for days to 250 lb, backfat, loin eye area, and lean growth rate. Analysis was by the REMLf90 program of I. Misztal using a multiple-trait animal model with fi...

A single nucleotide polymorphism (C/T) in bovine leptin, resulting in an arginine to cysteine amino acid substitution (p.Arg25Cys), has previously been shown to have an impact on carcass characteristics. Given the significant energetic relationship between fat and animal efficiency, further evaluation of this SNP across larger animal populations is warranted. Of the total number of 136 286 geno...

The aim of this study was to provide information on the fatty acid profile of different adipose depots – subcutaneous (upper and inner backfat layers) and intramuscular (m. Longissimus dorsi) in East Balkan pigs. The animals were reared in free-range conditions and slaughtered at an average live weight of 107±1.65kg. The results of the study showed that the various adipose tissues in pigs have ...

Correlated responses in reproductive and carcass traits from a line of Duroc pigs selected for increased 200-d weight along with a randomly selected control line were studied in 189 litters (116 select, 73 control) and 191 pigs (106 select, 85 control), respectively. Reproductive and maternal traits studied included litter sizes born, born alive, and alive at 21 d and litter weight at birth and...