title: Effects of feeding a single or sequence of beta-adrenergic agonists on cull cow meat quality.
abstract: Sixty cull cows were implanted and assigned to four treatments: C = concentrate ration only; RH = supplemented with ractopmaine-HCl (8.33 mg/kg of feed) for 25 d; ZH = supplemented with zilpaterol-HCl (ZH) (200mg head (-1)d(-1)) for the last 20 d; and RH + ZH = supplemented with RH for 25 d followed by ZH for 20 d. All cows were fed a concentrate ration for 74 d. Infraspinatus steaks from cows supplemented with RH and/or ZH had lower (P<0.05) shear force than steaks from C cows. Longissimus (LM) steaks from the 6-8th rib section of ZH and RH+ZH cows had decreased (P<0.0001) desmin degradation at 10 and 21 d postmortem compared to steaks from C and RH cows. Collagen solubility of the LM was increased (P<0.05) by ZH and RH+ZH compared to C. There were no treatment differences in 12th rib LM tenderness when enhanced with calcium lactate. Color and sensory traits of meat from RH+ZH cows were not different from C but flavor intensity was greater and off-flavor less than for C cows.
authors.affiliation: Department of Animal Sciences and Industry, Kansas State University, Manhattan, KS 66506, United States.
authors.forename: M J
authors.initials: MJ
authors.lastname: Weber
authors.forename: M E
authors.initials: ME
authors.lastname: Dikeman
authors.forename: J R
authors.initials: JR
authors.lastname: Jaeger
authors.forename: J A
authors.initials: JA
authors.lastname: Unruh
authors.forename: L
authors.initials: L
authors.lastname: Murray
authors.forename: T A
authors.initials: TA
authors.lastname: Houser
mesh_terms: D000318:Adrenergic beta-Agonists / Q000008:administration & dosage*; D000821:Animal Feed; D000818:Animals; D002417:Cattle; D003094:Collagen / Q000378:metabolism; D003116:Color; D003296:Cooking; D019587:Dietary Supplements; D005260:Female; D005503:Food Additives / Q000494:pharmacology; D063427:Food Quality; D006801:Humans; D008460:Meat / Q000032:analysis*; D018482:Muscle, Skeletal / Q000737:chemistry / Q000187:drug effects; D011180:Postmortem Changes; D059748:Proteolysis / Q000187:drug effects; D013649:Taste; D014297:Trimethylsilyl Compounds / Q000008:administration & dosage*
chemical_list: D000318:Adrenergic beta-Agonists; D005503:Food Additives; D014297:Trimethylsilyl Compounds; C475840:Zilpaterol; D003094:Collagen