ENERGETIC VALUE OF FORAGES FROM SEMI-ARID REGION AND DIGESTIBILITY OF RATIONS FOR NAKED NECK PULLETS

Abstract

The feeding programs for naked neck chickens in semi-intensive production system from brazilian equatorial semi-arid environment, must consider regional food availability and respective nutritional values. Thus, to evaluate the digestibility and metabolizable energy of alternative forages, it was used 240 naked neck pullets (Isa Label lineage) receiving water and ration ad libitum, pair-housed in cages for total collection of excreta on conventional warehouse. It was used a completely randomized design with factorial arrangement (5x2): one control ration (corn and soy meal) and other four experimental rations with silk flower hay (Calotropis procera), cassava leafs hay (Manihot esculenta), kills pasture hay (Senna obtusifolia) or leucaena leafs hay (Leucaena leucocephala), and all rations were balanced for two growing phases, between 8 and 10 weeks (young pullets) and between 14 and 16 weeks of age (old pullets). The values of apparent digestibility of nutrients for all experimental rations were lower than control ration (P <0.05) and it was observed general means of 72.18% for dry matter, 78.12% for crude protein, 66.90% for ether extract, 28.08% for neutral detergent fiber, 18.51% for the acid detergent fiber, 71.64% for gross energy and availability of 15.61% for mineral matter. The general mean of apparent and corrected metabolizable energy of alternative forages was 1217 kcal/ kg and 1108 kcal/kg, respectively, and the higher value was determined for leucaena hay and the lower value for silk flower hay (P <0.05).