Abstract: A metabolism trial and a growth-performance trial were conducted to evaluate the influence of level of supplementation (6, 12, 18 and 24%, DM basis) on the replacement feeding value of cane molasses in a steam-flaked corn-based finishing diet. Molasses replaced steam-flaked corn in the diet. Four Holstein steers (317 kg) with cannulas in the rumen and proximal duodenum were used to evaluate treatment effects on digestive function. There were no treatment effects (p>0.20) on ruminal digestion of OM, NDF and feed-N. Ruminal microbial efficiency (g microbial N passing to the small intestine per kg OM fermented) decreased (linear effect, p<0.10) with increasing molasses level. Increasing molasses level did not affect (p>0.20) total tract OM digestion, but decreased total tract digestion of starch (linear effect, p<0.01), N (linear effect, p<0.05) and DE (linear effect, p = 0.06). The DE value of cane molasses was not affected by level of addition, averaging 2.98 Mcal kg-1. Sixty-four medium-frame crossbred heifers (447 kg) were used in a 61-d trial to evaluate treatment effects on growth performance. Increasing dietary molasses level decreased (linear effect, p<0.05) ADG, DMI (linear effect, p<0.05), gain efficiency (linear effect, p<0.01) and dietary NEm and NEg (linear effect, p<0.01). Given that the NEm and NEg values of steam-flaked corn are 2.38 and 1.68 Mcal kg-1 respectively, then the corresponding values for cane molasses were 1.30 and 0.73 Mcal kg-1, respectively. These NE values are considerably less (24 and 32%, respectively) then expected based on tabular values and observed dietary DE value.
M.F. Montano , L.R. Flores , J.F. Calderon , V.M. Gonzalez , J. Salinas and R.A. Zinn , 2009. Influence of Level of Addition on the Feeding Value of Cane Molasses in Growing-Finishing Diets for Feedlot Cattle. Journal of Animal and Veterinary Advances, 8: 190-194.