Nutrient digestibility, nitrogen balance and rumen metabolites profile of growing Yankasa rams fed Brachiaria ruziziensis with concentrate mixture ratios in a total mixed ration

Abstract

A Digestibility trial which lasted for (21) days was carried out at the metabolic pen of the Small Ruminant Research Programme of the national animal production Research Institute (NAPRI), Ahmdu Bello University, Shika-Zaria to determine the nutrient digestibility, nitrogen balance and rumen metabolites concentration of growing Yankasa rams fed different ratios of Brachiaria ruziziensis and concentrate in a total mixed ration in Northern Guinea Savanna of Nigeria. Twelve healthy Growing Yankasa rams with an average live weight of 21.75kg±1kg were randomly allocated to four treatments with three replicates in a Complete Randomized Design (CRD). The treatment diets were ratio of Brachiaria ruziziensis to concentrate: (90:10), (80:20), (70:30) and (60:40) mixtures. The DM, OM, CP, CF, EE NFE and ADF digestibility showed significant variation (P<0.05) across the treatments. The Crude protein digestibility (CPD) was significantly (P<0.05) higher (84.25%) in (60:40) ratio B.ruziziensis to concentrate mixture while the least value of 76.12% was recorded in rams fed B.ruziziensis to concentrate mixture (90:10) ratio. Nitrogen intake, nitrogen absorbed, nitrogen retained and absorbed as percentage of intake (61.28%, 59.16%, 57.58%, 93.75% and 96.48%) respectively was significantly higher (P<0.05) in animals fed (60:40) mixture ratio. Rumen pH (6.80), Total volatile fatty acid (TVFA) (44.87), Rumen Ammonia nitrogen (NH₄-N) (16.18) significantly (P<0.05) differed across treatments with animal fed (60:40) ratio of B.ruziziensis to concentrate mixture recorded the highest value. Therefore, it could be concluded from this study that feeding Yankasa rams with 60:40 ratio B.ruziziensis to concentrate mixture ratio in a total mixed ration improved nutrient digestibility, nitrogen retention and rumen metabolites concentration in yankasa rams. Feeding of B.ruziziensis to concentrate at a ratio of 60:40 in a total mixed ration is hereby recommended for livestock farmers for better utilization in the Northern Guinea Savanna of Nigeria.