Rice bran as a supplement to elephant grass for cattle and buffalo in Indonesia: 1. Feed intake, utilization and growth rates

Abstract

SUMMARYIndonesian Ongole and swamp buffalo bulls were fed ad libitum a diet of elephant grass (Pennisetum purpureum) with five levels of rice bran (0, 1·2, 2·4, 3·6 and 4·8 kg/head/ day) in a study lasting 161 days. Measurements were made of the digestibility of the diet, the balances of nitrogen, phosphorus, calcium and water and the metabolizability of the gross energy. Using multiple regressions, the daily intakes of metabolizable energy were partitioned between maintenance and growth.Feeding rice bran stimulated appetite, initially improved feed conversion efficiency and increased growth rates. Each additional kilogram of rice bran fed depressed grass dry-matter intake by 0·8 kg in the buffaloes and 0·6 kg in Ongoles. Rice bran had little effect on digestibility of dry matter, organic matter and energy. Metabolizable energy contents of rice bran and elephant grass were calculated to be, respectively, 9·5 and 8·2 MJ/kg dry matter. Nitrogen and phosphorus status was improved in the supplemented animals but the balance of calcium was adversely affected. Voluntary feed intake was always higher in the buffaloes but the differences were reduced with increasing rice-bran supplementation.Metabolizable energy requirements for maintenance and growth did not differ significantly between Ongole and buffaloes and were similar to values calculated for British animals.