title: Effects of porcine somatotropin on growth and carcass composition of Meishan and Yorkshire barrows.
abstract: Effects of porcine somatotropin (pST) on growth and carcass characteristics of Meishan (Ms) and Yorkshire (Y) barrows given 3 mg of pST or saline daily were determined for two end points. First, 26 Ms and 26 Y barrows were treated from 119 d of age until the Y barrows reached 108 kg. Second, another 18 Ms barrows were treated to 108 kg BW. Age- and weight-matched treatments were analyzed. Results for both groups indicated pST effects (P < .05) for feed conversion (+) and intake (-), dressing percentage (-), percentage of carcass fat (-) and protein and water (+), leaf fat (-), backfat (BF) thickness (-), longissimus muscle area (LMA; +), skin thickness (+), muscle firmness and marbling scores (-), organ weights (+), belly (-), clear plate (-), ham (+), and total boneless cuts (BC; +). Somatotropin effects were also present for loin (-) and boneless Boston butt (BBB; +) in the age-matched group and for ADG (+), carcass weight (-), loin (-), jowl (-), and tenderloin (+) in the weight-matched group. Breed effects (P < .05), in favor of Y barrows, in both treatments existed for ADG (+) and feed intake (+), carcass weight (+), dressing percentage (+), LMA (+), skin thickness (-), muscle color and firmness scores (-), muscling score (+), all wholesale cuts (WC; +) except clear plate (age-matched), all trimmed cuts (TC; +) except picnic shoulder (weight-matched), and all BC (+). Breed effects, in favor of Y barrows, were also determined for carcass length (+), percentage of carcass ash (-), leaf fat (+), average BF thickness (+), and heart (-) and liver (-) weights in age-matched animals and percentage of carcass fat (-), protein (+), water (+), leaf fat (-), 10th rib, average, and P2 BF thicknesses (-), marbling score (-), femur length (-), and liver weights (+) in weight-matched animals. A higher response to pST (P < .05) was determined in Ms barrows than in Y barrows for percentage of carcass protein (+), liver (+), and heart (+) in the age-matched treatment and 10th rib BF thickness (-) and heart weight (+) in the weight-matched treatment. Yorkshire barrows treated with pST had more improved values for color score (+; age-matched) and BBB (+; weight-matched).
authors.affiliation: Department of Animal Sciences, University of Illinois, Urbana 61801.
authors.forename: B R
authors.initials: BR
authors.lastname: White
authors.forename: Y H
authors.initials: YH
authors.lastname: Lan
authors.forename: F K
authors.initials: FK
authors.lastname: McKeith
authors.forename: D G
authors.initials: DG
authors.lastname: McLaren
authors.forename: J
authors.initials: J
authors.lastname: Novakofski
authors.forename: M B
authors.initials: MB
authors.lastname: Wheeler
authors.forename: T R
authors.initials: TR
authors.lastname: Kasser
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects / Q000254:growth & development; D000704:Analysis of Variance; D000818:Animals; D001823:Body Composition / Q000187:drug effects*; D001947:Breeding; D004435:Eating; D013006:Growth Hormone / Q000494:pharmacology*; D008297:Male; D008460:Meat / Q000592:standards*; D024510:Muscle Development; D009132:Muscles / Q000187:drug effects; D011897:Random Allocation; D011994:Recombinant Proteins / Q000494:pharmacology; D013552:Swine / Q000254:growth & development*
chemical_list: D011994:Recombinant Proteins; D013006:Growth Hormone