Effect of different feed grinding fineness on the performances and digestive efficiency of growing rabbits

Abstract

In this study, two experiments were carried out. In the first experiment, we studied the effect of commercial feeds, differing in the grinding level of their constituents (group C was fed a diet milled with the process used for commercial feeds, group F and group G received the same diet ground more finely or coarsely, respectively), on the growth performances of rabbits and on some characteristics of the caecum and its content. The second experiment, an in vivo digestibility experiment, was carried out to study the influence of the same diets on the digestive efficiency of growing rabbits. The different particle sizes of the feeds did not significantly influence feed intake, weight gain and feed efficiency or slaughtering parameters of growing rabbits. The different grinding levels of the diets did not influence the apparent faecal digestibility of dry matter, organic matter and gross energy. The cell wall polysaccharides digestibility was, however, significantly decreased in the F group rabbits (P $< 0.01$). The different particle sizes had no effects on the caecal content characteristics nor were anatomohistopathological lesions found. Rabbits exhibit a great capacity to adapt to diets with somewhat different particle sizes.