title: Effects of animal and supplement characteristics on average daily gain of grazing beef cattle.
abstract: Effects of animal gender and age, use of a growth stimulant, and supplementation with grain alone or grain plus other substances on ADG by growing beef cattle grazing bermudagrass paddocks with sod-seeded rye, wheat, and ryegrass were determined. Two grazing experiments (Exp. 1: late winter through mid-spring; Exp. 2: late spring through mid-summer) were conducted. Experiment 1 used 96, 12- to 13-mo-old Simmental-cross calves (heifers, 240 kg; steers, 272 kg), half of which were implanted with zeranol. Within each implant treatment, cattle received no supplement or .5% BW (DM) of ground corn alone or plus a mix of protein meals, zinc sulfate, thiamin-HCl, or salt. Daily gain was higher (P less than .05) with than without supplementation and was similar (P greater than .10) among supplement treatments. In Exp. 2, 96 crossbred beef steers, approximately 7 (230 kg) or 15 mo old (250 kg), were not supplemented (control) or received .5% BW (DM) of ground corn on d 1 to 84 (C-C), corn plus a protein meal mix on d 1 to 84 (CP-CP), corn on d 43 to 84 (O-C), corn plus the protein meal mix on d 43 to 84 (O-CP), or corn on d 1 to 42 and corn plus the protein meal mix on d 43 to 84 (C-CP). Daily gain on d 1 to 84 was affected (P less than .05) by supplement, age, implant, and the supplement x implant interaction (nonimplanted: .37, .56, .68, .40, .49, and .49; implanted: .37, .62, .54, .49, .70, and .71 kg for control, C-C, CP-CP, O-C, O-CP, and C-CP, respectively).
authors.affiliation: Dept. of Anim. and Poult. Sci., University of Arkansas, Fayetteville 72701.
authors.forename: A L
authors.initials: AL
authors.lastname: Goetsch
authors.forename: G E
authors.initials: GE
authors.lastname: Murphy
authors.forename: E W
authors.initials: EW
authors.lastname: Grant
authors.forename: L A
authors.initials: LA
authors.lastname: Forster
authors.forename: D L
authors.initials: DL
authors.lastname: Galloway
authors.forename: C P
authors.initials: CP
authors.lastname: West
authors.forename: Z B
authors.initials: ZB
authors.lastname: Johnson
mesh_terms: D000273:Adipose Tissue / Q000254:growth & development; D000367:Age Factors; D000821:Animal Feed; D000818:Animals; D002417:Cattle / Q000254:growth & development*; D004044:Dietary Proteins / Q000008:administration & dosage; D004343:Drug Implants; D005260:Female; D005527:Food, Fortified; D008297:Male; D012727:Sex Characteristics; D015144:Southeastern United States; D015430:Weight Gain; D015029:Zeranol / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D004044:Dietary Proteins; D004343:Drug Implants; D015029:Zeranol