Effect of Replacing Corn Silage with Sweet Sorghum Silage on Digestibility and Performance of Dairy Cows

The objective of this experiment was to study the effects of replacing corn silage with sweet sorghum silage on digestibility, productive performance, rumen parameter and feeding behavior of dairy cows. For this purpose, corn silage was substituted by sweet sorghum silage at levels of 0 (control group), 33.3, 66.6 and 100 percent of dry matter. Treatments were randomly assigned to eight Holstein dairy cows with average of 35.5 kg/d milk production in a 4×4 Latin square design (replicated in four periods that were 21 days). In this experiment, intake of DM, CP, NDF and ADF were not significantly different among treatments, but replacing at all levels reduced digestibility of these components. However, milk yield and milk composition were not significantly different. Rumen volatile fatty acids were higher in control treatment, but pH and ammonia nitrogen contents of the rumen were not significantly difference among treatments. Also, replacing corn silage significantly increased rumination time in 100 percent sweet sorghum silage treatment than control treatment. Results of this experiment showed that corn silage could be replaced by sweet sorghum silage without any detrimental effect on DM intake and milk production.