Technical note: Health status and growth performance of rabbits fed diets with different starch level during the post-weaning period.

Abstract

A total of 240 rabbits (Hyplus®), weaned at 35 days of age, were used for growth rate and health status evaluation. Rabbits were divided into two groups (group S14 and group S12), and fed diets S14 (diet Starch 14%) and S12 (diet Starch 12%) formulated according to the most recent recommendations for rabbit feeding. The study was performed on a commercial farm. The diets were similar in the level of crude protein, fibre fractions and fat, but differed in the level of starch (14.4 vs. 11.9% in the S14 and S12 diets, respectively) and consequently digestible energy (10.0 vs. 9.6 MJ/kg), as well as in the digestible protein/digestible energy ratio. Rabbits of the S14 group received diet S14 from weaning to slaughter (77 days of age). Those in the S12 group received diet S12 from weaning to 49 days of age and were then fed with the S14 diet till slaughter. No significant differences were observed in feed intake between groups. For the entire fattening period, the weight gain values observed for the rabbits of the S12 group, were lower than those observed of the S14 group, but non significant differences were recorded (39.9 vs. 41.3 g/d, P=0.10). Rabbit mortality was relatively low and no significant differences were recorded between groups, either during post-weaning or in the finishing period. However, both morbidity (P=0.01) and health risk index (P=0.03) were observed to be significantly higher in rabbits of the S12 group than in those of the S14 group. The highest number of sick rabbits in the S12 group was recorded before the change of diet. Similar morbidity was subsequently observed in both groups. It can be concluded that i) a lower dietary starch level did not prevent digestive troubles in weaned rabbits and ii) a 14% dietary starch level is suitable for both growth and good health status in the post-weaning and finishing period.