title: Effects of ractopamine administration and castration method on muscle fiber characteristics and sensory quality of the longissimus muscle in two Piétrain pig genotypes.
abstract: Single and combined effects of ractopamine supplementation (RAC, 7.5 vs. 0 ppm), castration method (surgical castration: SC vs. immuno-castration: IM) and genotype (genotype A: GA vs. GB containing 25% or 50% Piétrain) were determined on longissimus muscle (LM) fiber traits and quality of pork (n=512). RAC increased fiber IIX cross-sectional area (P=0.009) and decreased glycolytic potential (P=0.02) and pork tenderness (P<0.001). Fiber traits indicated that LM of IM pigs was more oxidative (P<0.05) and meat had slightly higher (P=0.04) off-flavor score and WBSF than SC. LM from GB pigs was paler (P<0.05) and had greater (P<0.05) glycolytic potential, IIX fiber cross sectional area and pork off-flavor than GA. RAC supplementation, castration method and genotype or their combination affected some fiber traits and some quality parameters but differences reported were small indicating these treatments or their combination could be used without major prejudice to meat quality.
authors.affiliation: College of Food Science and Engineering, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China; Agriculture and Agri-Food Canada, Food Research and Development Centre, Saint-Hyacinthe, QC J2S 8E3, Canada; Agriculture and Agri-Food Canada, Dairy and Swine and Development Research Centre, Sherbrooke, QC J1M 0C8, Canada; Institute of Agricultural and Livestock Products, Inner Mongolia Academy of Agricultural & Husbandry Sciences, Hohhot, Inner Mongolia 010031, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Agriculture and Agri-Food Canada, Food Research and Development Centre, Saint-Hyacinthe, QC J2S 8E3, Canada. Electronic address: claude.gariepy@agr.gc.ca.
authors.forename: Claude
authors.initials: C
authors.lastname: Gariépy
authors.affiliation: College of Food Science and Engineering, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Jin
authors.affiliation: IRTA, Finca Camps i Armet, Monells 17121, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Font I Furnols
authors.affiliation: Agriculture and Agri-Food Canada, Food Research and Development Centre, Saint-Hyacinthe, QC J2S 8E3, Canada.
authors.forename: Jacinthe
authors.initials: J
authors.lastname: Fortin
authors.affiliation: Agriculture and Agri-Food Canada, Dairy and Swine and Development Research Centre, Sherbrooke, QC J1M 0C8, Canada; Département des sciences animales, Faculté des sciences de l'agriculture et de l'alimentation, Université Laval, HoustonPavillon Paul-Comtois, Québec City, QC G1V A06, Canada.
authors.forename: Luiene M
authors.initials: LM
authors.lastname: Rocha
authors.affiliation: Agriculture and Agri-Food Canada, Dairy and Swine and Development Research Centre, Sherbrooke, QC J1M 0C8, Canada.
authors.forename: Luigi
authors.initials: L
authors.lastname: Faucitano
mesh_terms: D000318:Adrenergic beta-Agonists / Q000008:administration & dosage*; D000818:Animals; D017849:Animals, Inbred Strains; D055598:Chemical Phenomena; D003269:Contraception, Immunologic / Q000009:adverse effects / Q000662:veterinary; D003433:Crosses, Genetic; D004032:Diet / Q000662:veterinary*; D063427:Food Quality; D006019:Glycolysis; D006133:Growth Substances / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D008460:Meat / Q000032:analysis*; D055595:Mechanical Phenomena; D018485:Muscle Fibers, Skeletal / Q000737:chemistry* / Q000378:metabolism; D009919:Orchiectomy / Q000009:adverse effects / Q000662:veterinary; D010627:Phenethylamines / Q000008:administration & dosage*; D010860:Pigments, Biological / Q000032:analysis / Q000096:biosynthesis; D011792:Quebec; D012677:Sensation; D034421:Sus scrofa; D013649:Taste
chemical_list: D000318:Adrenergic beta-Agonists; D006133:Growth Substances; D010627:Phenethylamines; D010860:Pigments, Biological; C060897:ractopamine
keywords: Castration; Genotype; Muscle fiber; Pork; Ractopamine; Sensory quality