Evaluation of wheat or corn dried distillers' grains with solubles on performance and carcass characteristics of feedlot steers

摘要

Walter, L. J., Aalhus, J. L., Robertson, W. M., McAllister, T. A., Gibb, D. J., Dugan, M. E. R. and McKinnon, J. J. 2010. Evaluation of wheat or corn dried distillers' grains with solubles on performance and carcass characteristics of feedlot steers. Can. J. Anim. Sci. 90: 259-269. A study was conducted on crossbred steers (n = 275; 376 +/- 24 kg) to evaluate performance and carcass quality of cattle fed wheat or corn dried distillers' grains with solubles (DDGS). The control ration contained 86.6% rolled barley grain, 5.7% supplement and 7.7% barley silage (DM basis). The four treatments included replacement of barley grain at 20 or 40% of the diet (DM basis) with wheat or corn DDGS. Steers were slaughtered at a common end weight of 645 kg with 100 steers randomly (n = 20 per treatment) selected for determination of the retail yield of sub-primal boneless boxed beef (SPBBB). Data were analyzed as a completely randomized design using pen as the experimental unit. Feeding increasing levels of wheat DDGS led to a quadratic increase in dry matter intake (DMI) (P <0.01), whereas increasing levels of corn DDGS led to a quadratic decrease in DMI (P = 0.01). Average daily gain was not influenced (P = 0.13) by feeding wheat or corn DDGS, but cattle fed corn DDGS exhibited a quadratic increase (P = 0.01) in gain:feed. As a result, a quadratic increase (P <0.01) in calculated NEg of the diet was observed as corn DDGS levels increased. A linear decrease (P =0.04) in days on feed (169, 166 and 154 d) was noted when increasing levels of wheat DDGS (0, 20 and 40%) were fed. Dressing percentage increased in a linear fashion with wheat DDGS (P <0.01) inclusion level and in a quadratic fashion (P = 0.01) as corn DDGS inclusion level increased although other carcass traits were not affected (P >0.10) by treatment. The results indicate that replacement of barley grain with corn or wheat DDGS up to 40% of the diet (DM) can lead to superior performance (improved gain:feed or reduced days on feed, respectively) with no detrimental effect on quality grade or carcass SPBBB yield.