ENERGY AND PROTEIN REQUIREMENT OF POST-WEANING BALI CATTLE IN EAST TIMOR

Post-weaning cattle require a certain amount of energy and protein in order to grow optimally. Offered a mixture of several feed ingredients aims to maximize effect of the association of nutrient content. Randomized Block Design consisted of four ration treatments with four blocks of liveweight as replicate was used in this study. This study used 16 bulls Bali cattle post-weaning offered rations based on dry matter were: A (100% field grass); B (80% field grass + 20% Corypha elata robx); C (field grass 80% + 20% Leucaena L) and D (grass field 80% + 10% Corypha elata robx + 10% Leucaena L). Variable measured were body composition, energy and protein requirement. Calculation of energy and protein requirements is based on measurements of body composition using the urea space technique. Blood samples were taken through the jugular vein as much as 10 ml, then injected urea physiologically with a concentration of 30% about 0.43 per kg W0.75. After 12 minutes of injection, blood is taken to analyze the levels of urea. Protein requirements for Bali cattle are calculated by summing protein requirement for maintenance and growth. Energy requirement for growth can be calculated by dividing energy retention with corrected weight gain with partial efficiency. Results showed that the treatments caused not significantly different in consumption, weight gain, energy and protein retention. Energy and protein requirement for maintenance of postweaning cattle in East Timor are: 0.64 W0.75 MJ / d and 8.18 g/W0.75 g/d, while the energy and protein requirement for growth are 14.98 ?W MJ/d and 226.14 ?W /d. KEYWORDS: Local feed, energy and protein requirement, post-weaning bulls.