Palma em substituição ao farelo de trigo na dieta de ovinos

Abstract

he objective of this study was to evaluate the effect of replacement of wheat bran by cactus pear ( 0, 25, 50, 75 and 100% ) in diets based on sugar cane, to evaluate the intake and digestibility of nutrients, nitrogen balance, fiber ruminal dynamics, microbial protein synthesis and ruminal parameters – pH, N-NH3 concentration and production of short chain fatty acid in sheep. Five Santa Ines sheep, canulated in rumen, with average initial live weight 34.02 ± 3.6 kg, designed in a 5 × 5 latin square. The dry matter, organic matter, crude protein, ether extract, total digestible nutrients and fiber fixed neutral detergent intake showed quadratic effect (P<0,05) with replacement of wheat bran by cactus pear. The apparent digestibility of dry matter, organic matter and crude protein showed a linear increase (P<0,05). This trial showed a quadratic effect (P<0,05) for the passage rate of neutral detergent fiber. The intake and nitrogen absorption showed (P<0,05) similar behaviour to dry matter intake. The replacement of wheat bran by cactus pear favoured the linear increased (P<0,05) of values observed for the nitrogen balance. The N-NH3 concentration did not limit the microbial protein synthesis, showed linear increase (P<0,05) for replacement of wheat bran by cactus pear and showed a quadratic effect (P <0,05) for collection schedules, before feeding, two, four and six hours after the food ingestion. There was a quadratic effect (P<0,05) for the production of microbial crude protein and nitrogen, and ruminal microbial production of short chain fatty acids. The ruminal pH was within the optimum range (6,7±0,5) for adequate fermentation in the rumen, increased linearly (P<0.05) with replacement and showed a quadratic effect (P<0.05) for collection schedules. Recommended the development of performance test, to verify the extent to which the cactus pear can replace wheat bran in diets based on sugarcane, without loss to animal production