[Diet type, grinding size and anatomo-functional characteristics of the proximal digestive tract in the rabbit]

Two diets containing either dehydrated lucerne (40%) or dehydrated beet pulp (50%) both being coarsely (4 mm) of finely (1 mm) ground before pelleting, were fed to 120 rabbits after weaning. Feed intake and weight gain were estimated. After 79 days, 11 rabbits in each group were slaughtered between 14.00 and 17.00 h. The parameters measured were stomach and ileal weights, dry matter, fibre and nitrogen contents, volatile fatty acid concentrations. Gastric emptying and intestinal transit time were estimated in each group. Rabbits fed the beet pulp diet had a better feed conversion ratio associated with a higher solid matter gastric retention and also a longer jejuno-ileal transit time. Finely ground diet further increased the transit time, particularly in the ileum, which was also associated with a higher concentration of fermentation by-products.