title: Heterosis for meat quality and fatty acid profiles in crosses among Bos indicus and Bos taurus finished on pasture or grain.
abstract: Physicochemical properties and fatty acid profiles of meat from Bos indicus, Bos taurus and crossbred B. taurus×B. indicus bullocks (n=216), finished on pasture or grain, were used to estimate the effects of heterosis. Meat quality and fatty acid profiles generally benefited with crossbreeding, but the advantages from heterosis differed among finishing systems. The Warner-Bratzler shear-force in fresh and aged meat was reduced due to heterosis in pasture-finishing, but the effect was minor under grain-finishing. With pasture-finishing, heterosis caused an increase of 5% in CLA concentration, but few other changes in fatty acid profiles. In grain-finishing, heterosis caused a reduction in intramuscular fat and cholesterol, increased amounts of PUFA, n-6 fatty acids and PUFA/SFA ratio, and a decline in atherogenic index. The Δ(9) desaturase estimated activity in crossbreds showed a behavior close to B. indicus, suggesting the existence of few loci and a dominance genetic effect on enzymes involved in fatty acid synthesis and metabolism.
authors.affiliation: CIISA, Faculdade de Medicina Veterinária, Universidade Técnica de Lisboa, 1300-477 Lisboa, Portugal. ltgama@fmv.utl.pt
authors.forename: L T
authors.initials: LT
authors.lastname: Gama
authors.forename: M C
authors.initials: MC
authors.lastname: Bressan
authors.forename: E C
authors.initials: EC
authors.lastname: Rodrigues
authors.forename: L V
authors.initials: LV
authors.lastname: Rossato
authors.forename: O C
authors.initials: OC
authors.lastname: Moreira
authors.forename: S P
authors.initials: SP
authors.lastname: Alves
authors.forename: R J B
authors.initials: RJ
authors.lastname: Bessa
mesh_terms: D000821:Animal Feed; D000822:Animal Husbandry / Q000379:methods; D000818:Animals; D050197:Atherosclerosis / Q000139:chemically induced; D001947:Breeding; D002417:Cattle; D002791:Cholesterol, Dietary / Q000378:metabolism; D004032:Diet; D004041:Dietary Fats / Q000378:metabolism*; D002523:Edible Grain; D005227:Fatty Acids / Q000235:genetics* / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000235:genetics / Q000378:metabolism; D056426:Genetic Loci; D006823:Hybrid Vigor; D044243:Linoleic Acids, Conjugated / Q000235:genetics / Q000378:metabolism; D008460:Meat / Q000032:analysis* / Q000592:standards; D018482:Muscle, Skeletal / Q000378:metabolism; D006109:Poaceae; D013045:Species Specificity; D013230:Stearoyl-CoA Desaturase / Q000235:genetics / Q000378:metabolism; D013314:Stress, Mechanical
chemical_list: D002791:Cholesterol, Dietary; D004041:Dietary Fats; D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D044243:Linoleic Acids, Conjugated; D013230:Stearoyl-CoA Desaturase