Performance and carcass characteristics of rabbits fed diets with different starch levels and fiber sources

The objective of the present study was to evaluate performance, quantitative and qualitative characteristics of the carcass in growing rabbits fed diets with different starch levels (22 or 32% on average) by high or low inclusion of corn grain and different fiber sources (alfalfa hay or soybean hulls), in a 2x2 factorial design. The experimental diets were pellets and fed ad libitum for 40 days to 40 rabbits weaned at 35 days, housed individually and assigned to a complete randomized design. No significant effects were observed for the interaction between the fiber sources and the starch levels to the parameters evaluated in this study. Higher feed intake was observed with diets contents alfalfa hay (91.27 g/d), but the weight gain and food conversion were significantly affected by the dietary treatments (overall mean of 30.18 g/d and 2.94, respectively). Carcass yield, protein level, protein and energy efficiency in the carcass showed greater values for the diets with high starch levels (50.20, 62.36, 56.38, and 30.04%, respectively). Diets with high starch level or with soybean hulls resulted in better indexes of food conversion and carcass characteristics, reflex of a better nutrient utilization efficiency.