Profiling of rumen fermentation and microbial population changes in goats fed with napier grass supplemented with whole corn plant silage

Abstract

The effects of different inclusion level of whole corn plant silage to Napier grass were observed in determining rumen fermentation and microbial population in goats. Fifteen male Boer cross goats around six months old of approximately 18.54±1.83 kg of b.wt., were used as experimental animals. The goats were assigned into five groups with three goats per treatment group. The five treatment groups consisted of different proportions of Napier Grass (G) and whole corn plant silage (CS)-G/CS, (T1) 100/0, (T2) 75/25, (T3) 50/50, (T4) 25/75 and (T5) 0/100, respectively. The mean concentrations of rumen NH3-N (mg dL-1) were not significant differences among the treatments, although T4 and T5 were slightly increased compared to other treatments. The total VFA production in the rumen fluid of the goat was not significantly different among the treatments, however; highest molar proportion of propionic acid and lowest proportion of acetic acid was observed in goat fed with T5 diets. Although the total bacteria population of rumen content was not significantly different among the dietary treatments, the population of R. albus, R. flavefaciens and F. succinogen showed significantly (p<0.05) among the treatments. The lowest population of methanogen and protozoa were detected in the rumen of goats fed T5 diet compared with other treatments. Thus, the animals fed with T5 diet showed the highest proportion of propionic acid and the lowest number of methanogen and protozoa population in the rumen.