In vitro digestibility of ruminant diet in response to protected feed substitution

Abstract

Abstract Excessive degradation high protein feed in the rumen can reduce nutrient utilization efficiency of feed in post rumen. Protected feed is expected to increase the undegraded proteins that enter and absorbed in the intestine. In vitro study was conducted to determine whether the protected feed can reduce rumen degradability as well as improving post-rumen degradability of feed. The protected feed used in this study was soybean meal and crude palm oil mixture (4: 1), added with 0.3% Agromix. Independent sample t-test was used to compare 2 treatments (T1/control = commercial ration; T2 = commercial ration with 4.4% protected feed substitution). Each dietary treatment was done in 6 replications. Both dietary treatments were tested for their digestibility using a 2-stage in vitro technique. Results showed that pH of rumen did not change. Compared to the T1, T2 showed lower (P<0.05) digestibility of dry matter (DMD), organic matter (OMD), and crude protein (CPD) in the rumen. In the post rumen, T2 showed greater (P<0.05) DMD, OMD and CPD than T1. It concluded that protected feed substitution effectively decreases digestibility in the rumen and increases post-rumen digestibility, imply that protected feed substitution can improve the nutrient utilization in the post rumen.