Optimization of Urea Supplementation to Goats in Cooked Rice Feeding Regimen Followed in Tamil Nadu

Background: Cooked rice had a low crude protein ranging between 9.2 and 12.6% but had a remarkably high nitrogen free extract (NFE above 84%) indicating a very wide gap in the available nitrogen to available soluble carbohydrate. Hence, the study was undertaken to investigate the effects of urea supplementation in cooked rice feeding regimen on nutrient utilization and production performance of goats. Methods: The in vitro dry matter and protein degradability characteristics of cooked rice were determined by using rumen simulation technique (RUSITEC). An animal experiment was conducted in twenty-four non descriptive kids at 90 days of age randomly divided into four treatments (T1 - 0%, T2 - 1.5%, T3 - 2.0% and T4 - 2.5% of urea in the diet as such basis) for 180 days. The average daily gain, daily feed intake and feed conversion ratio were recorded during the trial. The digestibility trial was conducted at the end of the trial for 15 days. Result: Rumen fermentation pattern of cooked rice revealed lower ruminal pH (5.5), effective degradability of DM and N of cooked rice were 52.5% and 33.2% respectively with 0.44% of rumen digestible nitrogen and 1.42% of potential microbial nitrogen production. The scope of urea supplementation was 1.85%. The average daily gain was 53.23, 71.66, 96.75 and 76.91g/day and feed conversion ratio were 9.70, 7.74, 6.61 and 8.52 in groups 0, 1.5, 2.0 and 2.5% respectively was significantly (P less than 0.01) improved in 2.0% urea supplementation over other treatments. Hence, it is advocated the supplementation of urea at 2.0% level as such basis along with cooked rice for enhanced growth performance of goats.