|Roberts, Andrew - Andy|
Submitted to: Professional Animal Scientist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/11/2003
Publication Date: 2/1/2003
Citation: FUNSTON, R.N., PATERSON, J.A., WILLIAMS, K.E., ROBERTS, A.J. EFFECT OF BODY CONDITION, INITIAL WEIGHT, AND IMPLANT ON FEEDLOT AND CARCASS CHARACTERISTICS OF CULL COWS. PROFESSIONAL ANIMAL SCIENTIST. 2003. V. 19. P. 233-238. Interpretive Summary: Sale of cull cows is a significant source of income for ranchers. Properly managing and marketing cull cows may mean the difference between a profit and a loss for a year. Feeding cull cows a feedlot ration for a period of time before selling may improve quality of animals and overall profitability. Often the cost of gain for cows will be higher than the sale price of cows at harvest; however, cow feeding may increase returns if price increases during the feeding period. Thus, it is important to consider seasonality of cull cow prices and price differences between cull cow slaughter grades when considering feeding cull cows. Neither initial weight or body condition affected performance (ADG) of cull cows in the feedlot in this research project. Implanting, however, improved feedlot performance and increased hot carcass weight and ribeye area.
Technical Abstract: Feeding cull cows an energy dense diet can increase amount and quality of marketable product. Furthermore, implanting cull cows with steroid implants may improve gain, feed efficiency, carcass traits, and overall eating quality. Therefore, objectives of this study were to determine effects of implant, initial BW, and body condition score (BCS) at the beginning of the study, on feedlot performance and final live animal and carcass weights, and carcass characteristics of cull cows fed a high concentrate diet for approximately 90 d. One-half (68) of the cows were allotted to implant treatment (Synovex-Plus®) by initial weight and BCS. Cows were fed a warm-up diet (50 to 60% concentrate, DM basis) for 14 d, and then fed a finishing (80 to 85% concentrate, DM basis) diet for the remainder of the study. Variations in initial weight of cows were associated positively (P<0.05) with final weight, hot carcass weight, ribeye area, and yield grade. Initial BCS had a positive affect (P<0.01) on back fat and ribeye area but did not influence (P>0.10) ADG, final weight, or hot carcass weight. Implant influenced (P<0.07) both feedlot and carcass characteristics; implanted cattle had 17 kg heavier final weight, 0.21 kg greater ADG, 18 kg heavier carcass weight, 8.8 cm2 larger ribeye, and 26 units less marbling. Initial weight, BCS, and implanting influence feedlot performance and carcass characteristics of cull cows.