title: Modification of mature non-reducible collagen cross-link concentrations in bovine m. gluteus medius and semitendinosus with steer age at slaughter, breed cross and growth promotants.
abstract: Increased meat toughness with animal age has been attributed to mature trivalent collagen cross-link formation. Intramuscular trivalent collagen cross-link content may be decreased by reducing animal age at slaughter and/or inducing muscle re-modeling with growth promotants. This hypothesis was tested in m. gluteus medius (GM) and m. semitendinosus (ST) from 112 beef steers finished at either 12 to 13 (rapid growth) or 18 to 20 (slow growth) months of age. Hereford-Aberdeen Angus (HAA) or Charolais-Red Angus (CRA) steers were randomly assigned to receive implants (IMP), ractopamine (RAC), both IMP and RAC, or none (control). RAC decreased pyridinoline (mol/mol collagen) and IMP increased Ehrlich chromogen (EC) (mol/mol collagen) in the GM. In the ST, RAC increased EC (mol/mol collagen) but decreased EC (nmol/g raw muscle) in slow growing CRA steers. Also, IMP increased ST pyridinoline (nmol/g raw muscle) of slow-growing HAA steers. Results indicated alteration of perimysium collagen cross-links content in muscle in response to growth promotants.
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada.
authors.forename: B C
authors.initials: BC
authors.lastname: Roy
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada.
authors.forename: G
authors.initials: G
authors.lastname: Sedgewick
authors.affiliation: Agriculture and Agri-Food Canada, 6000 C&E Trail, Lacombe, Alberta T4L 1W1, Canada.
authors.forename: J L
authors.initials: JL
authors.lastname: Aalhus
authors.affiliation: Alberta Agriculture and Rural Development, 6000 C&E Trail, Lacombe, Alberta T4L 1W1, Canada.
authors.forename: J A
authors.initials: JA
authors.lastname: Basarab
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada. Electronic address: hbruce@ualberta.ca.
authors.forename: H L
authors.initials: HL
authors.lastname: Bruce
mesh_terms: D000003:Abattoirs; D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000596:Amino Acids / Q000378:metabolism; D000822:Animal Husbandry / Q000379:methods; D000818:Animals; D001947:Breeding; D002417:Cattle; D003094:Collagen / Q000378:metabolism*; D006128:Growth; D013006:Growth Hormone / Q000494:pharmacology*; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism*; D010627:Phenethylamines / Q000494:pharmacology*; D011897:Random Allocation; D000069466:Red Meat / Q000032:analysis*; D013045:Species Specificity; D013314:Stress, Mechanical
chemical_list: D000318:Adrenergic beta-Agonists; D000596:Amino Acids; D010627:Phenethylamines; C060897:ractopamine; C015484:pyridinoline; D013006:Growth Hormone; D003094:Collagen
keywords: Collagen; Ehrlich chromogen; Implants; Meat tenderness; Pyridinoline; Ractopamine