Dietary impact of soybean haulms and/or garlic powder on rumen fermentation and microbial biomass of sheep

The need to assess the fermentation pattern in the rumen is important in evaluating alternative feeding resources that can be used for sustainable feeding regime in ruminants. This research assessed the rumen fermentation and microbial populations as affected by dietary soybean haulms and/or garlic powder in the diets of sheep. A total of fifteen (15) rams from crosses between Yankasa and Uda breeds were used for this experiment. The rams were balanced for weight and randomly divided into three (3) groups of five animals each and assigned three treatment diets in a completely randomised design. The three treatment diets were T1 (Control: no inclusion of soybean haulms), T2 (30% inclusion of soybean haulms in the diet), and T3 (30% inclusion of soybean haulms + 0.5% inclusion of garlic powder). Each animal served as a replicate and the animals were fed experimental diets for 77 days, thereafter, rumen samples were collected from all animals for sampling. Data were collected on rumen pH, volatile fatty acids and its proportions and microbial count were subjected to one-way analysis of variance using SPSS (version 23). Results obtained indicates that the rumen pH and metabolites measured, total counts for bacteria, fungi and protozoa were not affected (p>0.05) by inclusion of soybean haulms and/or garlic powder in the diet of sheep. However, populations of Bacillus spp. reduced (p<0.05) in group of sheep fed soybean haulms only (T2) compared to control (T1). Also, Isotricha spp. decreased (P<0.05) in group of sheep on soybean haulms only (T2) compared to those on soybean haulms and garlic powder T3). Some of the bacteria and protozoa species assessed in this experiment were not affected (p>0.05) by inclusion of soybean haulms in diet of sheep. Also, the addition of garlic to diet with soybean haulms did not further influence the fermentation pattern in the rumen. In conclusion, 30% of soybean haulms in diets of sheep without addition of garlic powder are recommended to maintain healthy fermentation pattern in the rumen.