| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
ANIMAL PRODUCTION |
* Department of Animal Science, Oklahoma State University, Stillwater, 74078 and
and
USDA, ARS Grazinglands Research Laboratory, El Reno, OK 73036
4 Correspondence: 208 Animal Science Bldg. (phone: 405-744-6621; fax: 405-744-7390; e-mail: horngw{at}okstate.edu).
Abstract
Two experiments were conducted to examine the effect of previous BW gain during winter grazing on subsequent growth, carcass characteristics, and change in body composition during the feedlot finishing phase. In each experiment, 48 fall-weaned Angus x Angus-Hereford steer calves were assigned randomly to one of three treatments: 1) high rate of BW gain grazing winter wheat (HGW), 2) low rate of BW gain grazing winter wheat (LGW), or 3) grazing dormant tallgrass native range (NR) supplemented with 0.91 kg/d of cottonseed meal. Winter grazing ADG (kg/d) for HGW, LGW, and NR steers were, respectively, 1.31, 0.54, 0.16 (Exp. 1) and 1.10, 0.68, 0.15 (Exp. 2). At the end of winter grazing, four steers were selected randomly from each treatment to measure initial carcass characteristics and chemical composition of carcass, offal, and empty body. All remaining steers were fed a high-concentrate diet to a common backfat end point. Six steers were selected randomly from each treatment for final chemical composition, and carcass characteristics were measured on all steers. Initial fat mass and proportion in carcass, offal, and empty body were greatest (P < 0.001) for HGW, intermediate for LGW, and least for NR steers in both experiments. Live BW ADG and gain efficiency during the finishing phase did not differ (P = 0.24) among treatments, but DMI (% of mean BW) for NR and LGW was greater (P < 0.003) than for HGW steers. Final empty-body composition did not differ (P = 0.25) among treatments in Exp. 1. In Exp. 2, final carcass and empty-body fat proportion (g/kg) was greater (P < 0.03) for LGW and NR than for HGW steers. Accretion of carcass fat-free organic matter was greater (P < 0.004) for LGW than for HGW and NR steers in Exp. 1, but did not differ (P = 0.22) among treatments in Exp. 2. Fat accretion in carcass, offal, and empty body did not differ (P = 0.19) among treatments in Exp. 1, but was greater (P < 0.05) for LGW and NR than for HGW steers in Exp. 2. Heat production by NR steers during finishing was greater (P < 0.02) than by HGW steers in Exp. 1 and 2. Differences in ADG during winter grazing and initial body fat content did not affect rate of live BW gain or gain efficiency during finishing. Feeding steers to a common backfat thickness end point mitigated initial differences in carcass and empty-body fat content. However, maintenance energy requirements during finishing were increased for nutritionally restricted steers that were wintered on dormant native range.
Key Words: Body Composition • Cattle • Feedlot Performance • Winter Grazing
This article has been cited by other articles:
|
|
 |
|
  W. A. Phillips and G. W. Horn Intake and digestion of wheat forage by stocker calves and lambs J Anim Sci, September 1, 2008; 86(9): 2424 - 2429. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. McPhee, J. W. Oltjen, J. G. Fadel, D. Perry, and R. D. Sainz Development and evaluation of empirical equations to interconvert between twelfth-rib fat and kidney, pelvic, and heart fat respective fat weights and to predict initial conditions of fat deposition models for beef cattle J Anim Sci, August 1, 2008; 86(8): 1984 - 1995. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. J. Winterholler, D. L. Lalman, M. D. Hudson, C. E. Ward, C. R. Krehbiel, and G. W. Horn Performance, Carcass Characteristics, and Economic Analysis of Calf-Fed and Wheat Pasture Yearling Systems in the Southern Great Plains Professional Animal Scientist, June 1, 2008; 24(3): 232 - 238. [Abstract] [PDF]
|
|
|
|
|
|
D. A. Chabot, C. D. Chabot, L. K. Conway, and S. A. Soto-Navarro Effect of fat supplementation and wheat pasture maturity on forage intake and digestion characteristics of steers grazing wheat pasture J Anim Sci, May 1, 2008; 86(5): 1263 - 1270. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. K. Duckett, J. P. S. Neel, R. N. Sonon Jr., J. P. Fontenot, W. M. Clapham, and G. Scaglia Effects of winter stocker growth rate and finishing system on: II. Ninth tenth eleventh-rib composition, muscle color, and palatability J Anim Sci, October 1, 2007; 85(10): 2691 - 2698. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. P. S. Neel, J. P. Fontenot, W. M. Clapham, S. K. Duckett, E. E. D. Felton, G. Scaglia, and W. B. Bryan Effects of winter stocker growth rate and finishing system on: I. Animal performance and carcass characteristics J Anim Sci, August 1, 2007; 85(8): 2012 - 2018. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. McPhee, J. W. Oltjen, T. R. Famula, and R. D. Sainz Meta-analysis of factors affecting carcass characteristics of feedlot steers J Anim Sci, November 1, 2006; 84(11): 3143 - 3154. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. W. Ross, T. K. Smith, C. R. Krehbiel, J. R. Malayer, U. DeSilva, J. B. Morgan, F. J. White, M. J. Hersom, G. W. Horn, and R. D. Geisert Effects of grazing program and subsequent finishing on gene expression in different adipose tissue depots in beef steers J Anim Sci, August 1, 2005; 83(8): 1914 - 1923. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Hersom, R. P. Wettemann, C. R. Krehbiel, G. W. Horn, and D. H. Keisler Effect of live weight gain of steers during winter grazing: III. Blood metabolites and hormones during feedlot finishing J Anim Sci, July 1, 2004; 82(7): 2059 - 2068. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Hersom, C. R. Krehbiel, and G. W. Horn Effect of live weight gain of steers during winter grazing: II. Visceral organ mass, cellularity, and oxygen consumption J Anim Sci, January 1, 2004; 82(1): 184 - 197. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
