Submitted to: Professional Animal Scientist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/29/2012
Publication Date: 9/21/2012
Citation: Gadberry, M.S., Beck, P.A., Gunter, S.A., Barham, B.L., Whitworth, W.A., Apple, J.K. 2012. Effect of corn- and soybean hull-based creep feed and backgrounding diets on lifelong performance and carcass traits of calves from pasture and rangeland conditions. The Professional Animal Scientist. 28:507-518. Interpretive Summary: To determine if creep feeding high-energy supplements for a 90-day period before weaning will improve the quality grade of carcasses after finishing, the Southern Plains Range Research Station and scientist from the University of Arkansas tested this premise in 3 locations with beef cows of English breeding nursing calves. Two creep types were compared to no creep feeding. One creep was corn based (high starch), while the other was soybean hull based (high digestible fiber). Creep feeds were fed at 1 percent of body weight for 90-days before weaning. After weaning, calves were put on pasture or high-fiber diets, and later placed in a feedlot where they were finished on steam-flaked corn-based diets. In the 2 locations with pastures of lower forage quality, creep feeding had similar effects on calf performance and carcass quality. Creep feeding increased average daily gain of calves before weaning, but had no effects on performance during backgrounding or finishing. In the location with pastures of high forage quality, creep did not improve average daily gain of calves before weaning. Because creep-fed calves at locations with lower forage quality were weaned at a heavier body weight, they did have heavier carcass weights after slaughter. However, no differences were noted in the quality of the carcasses regardless of locations. In conclusion, creep feeding improved average daily gain of calves in environments of lower forage quality with the additional body gain carrying over into the feedlot entry and potentially affecting hot carcass weight. Creep feeding and creep feed type at 1 percent of body weight (BW), however, did not enhance marbling, carcass quality grade, or consumer acceptance.
Technical Abstract: Three separate studies were conducted to investigate the life-long effect of creep feeding, creep feeding energy source (soybean hulls, SC, or corn, CC) and interactive effects of creep feed with backgrounding dietary energy source (soybean hulls, SBR, or corn, CBR) on calf growth performance, carcass measurements, and final product compared to no creep feeding (NC). Creep feed studies conducted at Southwest (SWREC) and Southeast (SEREC) Research and Extension Centers were on improved, warm-season and cool-season pastures, respectively; whereas the creep feed study conducted at the Southern Plains Experimental Range (SPER) was on native range. Creep feed intake was targeted at 1 percent body weight (BW), as-fed, beginning 90 day (d) before weaning. Calves at SWREC and SEREC were backgrounded on SBR or CBR, stepping up from 60 to 80 percent concentrate over 45 and 67 d, respectively, before feedlot finishing. Calves at SPER were co-mingled and grazed from late-March to early-July, before feedlot finishing. Creep feeding increased average daily gain (ADG) for SWREC (P = 0.01) and SPER (P < 0.01), but not SEREC (P = 0.18). Source of creep (SC verses CC) did not effect ADG pre-weaning for SWREC (P = 0.46) or SEREC (P = 0.93). The ADG of calves creep-fed SC was greater than CC during backgrounding during the SEREC study (P = 0.04) but not the SWREC study (P = 0.38). Backgrounding diet energy source did not affect ADG for SWREC (P > 0.10) or SEREC (P > 0.10). Creep-fed calves for SWREC and SPER entered the feedlot at a heavier weight than NC calves (P = 0.01 and P = 0.06, respectively). Final body weight before slaughter did not differ among dietary treatments within study; however, hot-carcass weight (HCW) was 17 kg greater due to CC from SPER (P = 0.02). Neither creep feeding, source of creep feed, nor backgrounding energy source had an effect (P = 0.67) on USDA quality grade (SWREC and SEREC) or marbling score (SPER). Treatments did not significantly (P = 0.17) alter Warner-Bratzler shear force, cooking loss, or percentage fat, moisture, protein or collagen of steaks for SWREC and SEREC calves. Steak taste panel scores were similar (P = 0.19) for juiciness, tenderness, flavor, and mouth feel among creep and background treatments imposed during the SWREC and SEREC studies. In conclusion, creep feeding improved ADG of calves in environments of lower forage quality with the additional BW gain carrying over into the feedlot entry and potentially affecting HCW. Creep feeding and creep feed type at 1 percent of BW, however, did not enhance marbling, carcass quality grade, or consumer acceptance.