An Overview on the Use of Urinary Purine Derivatives Excretion as a Method for Estimation of Rumen Microbial Protein Production in Swamp Buffaloes and Zebu Cattle

摘要: Respond models based on urinary excretion of purine derivatives (PD) as an index to predict rumen microbial protein production have been developed for European cattle and sheep. However, there is evidence suggest that those equations may not be applicable directly tropical swamp buffaloes (Bubalus bubalis) zebu Kedah-Kelantan (KK) (Bos indicus). To establish similar the above two species ruminants, three studies were conducted. The first study examined relationship between daily PD (Y, mmol) duodenal bases (PB) (X, mmol). relationships obtained Y = 0.12 X + 12.78 (r 2 =0.45) 0.85 7.15 =0.62) KK cattle, suggesting 12 85% supplied exogenous purines excreted in urine respectively. In second study, 8-[14C]-uric acid was used test hypothesis lower recovery due their higher recycling plasma compared cattle. Averaged non-renal loss [14C]-uric did differ significantly. A third conducted examine whether could absorption small intestine results indicated apparent rate a percentage disappearance segment significantly different from even though larger quantity digesta PB noted last 4 segments buffaloes. equation this published Due extremely low (12%), proposed should with great caution.