All-Forage Diets for Finishing Beef Cattle

Abstract

One trial, involving 48 heavy weanling calves, was conducted to study the feedlot performance, ruminal characteristics and carcass merit of cattle fed (1) an all-concentrate corn based diet, (2) a pelleted all-forage alfalfa based diet, (3) the all-concentrate diet followed by the all-forage diet and (4) the all-forage diet followed by the all-concentrate diet. Average daily gains (kg) and feed/gain ratio during the study for the four groups, respectively, were: 1.27, 5.71; 1.05, 10.06; 1.09, 7.98; 1.11, 8.14. The steers in group 1 were slaughtered at the end of the 168 days but steers in the other groups were kept on their respective diets until they reached an equivalent weight. Whereas steers fed regime 1 had superior feedlot performance and carcass quality the remaining 3 regimes resulted in similar responses. The steers fed the all-concentrate and all-forage diets had acetate: propionate ratios of 1.2:1 and 4.3:1, respectively. Steers fed only the all-forage diet graded low choice and had approximately half the amount of backfat as cattle finished on only the all-concentrate diet. A second trial, involving 48 heavy weanling calves was conducted to obtain the same criteria on cattle fed four pelleted all-forage diets based on (1) alfalfa hay, (2) 2/3 alfalfa hay: 1/3 timothy hay, (3) 1/3 alfalfa hay: 2/3 timothy hay and (4) timothy hay. Average daily gains (kg) and feed/gain ratio, respectively, were: 0.97, 10.98; 0.94, 11.91; 0.91, 12.63; 0.84, 12.70. Steers in group 1 were slaughtered at the end of 203 days but steers in the other groups were kept on their respective diets until they reached an equivalent weight. Group 1 steers gained faster (P<.05) than steers in group 4. The carcasses from the steers in all groups graded medium to high good.