Effect of Undegraded Protein and Energy Level on Rumen Fermentation Parameters and Microbial Protein Synthesis in Cattle

Abstract

An experiment was conducted to determine the effect of undegraded protein and energy level on rumen fermentation parameters and microbial protein synthesis in cattle. The benefit of the research was to inform about optimation of undegraded protein and energy level to increase nutrient utilization in dairy cows.The experiment was conducted in 4 month in Department of Animal Nutrition and Feed Science, Faculty of Animal Science Gadjah Mada University. The experiment used 4 female rumen fistulated Friesian Holstein Crossbred (FHC) of 3.0 – 3.5 years old and 350 – 400 kg body weight. The treatment of this experiment wereT1: undegraded protein 20% and energy 70% of requirement, T2 : undegraded protein 20% and energy 120% of requirement, T3: undegraded protein 30% and energy 70% of requirement and T4 :undegraded protein 30% and energy 120% of requirement with Latin square design. Variables observed were ruminal pH, NH3, volatile fatty acids (VFA) concentration and microbial protein synthesis. Collected data were analyzed statistically by analysis of variances, and this is report among treatments, then they were tested further by orthogonal contrast. The results showed that NH3 concentration for T1, T2, T3 and T4 (25.32; 24.99; 24.31 dan 23.41 mg/100 ml) were not significantly different and optimally after 1 h post feeding. Undegraded protein and energy level did not influence of VFA concentration rumen fluid. Kinetic concentration of VFA of ration with high energy (T2 and T4) disposed higher than restricted of energy (T1 and T3). Kinetic pH of ration with high UDP was lower (P<0.01) than ration with low UDP (3, 4 and 5 hours post feeding). N microbial supply of ration with high energy level was higher (P<0.05) than restricted energy (38, 37 Vs 28, 29 g/animal/day respectively). It was concluded that high level of UDP and energy could increasing rumen parameters fermentation and microbial protein synthesis in dairy cattle. Keywords : Undegraded protein, nitrogen, energy, supplementation