Influence of Toyocerin (Bacillus cereus var. toyoi) on the breeding performances of primiparous rabbit does

Abstract

[EN] This study was carried out to evaluate the effects of Bacillus cereus var. toyoi (Toyocerin¿ 109) on performance of rabbit does during two reproductive cycles. A total of 102 does were assigned to three treatments: T0 (basal diet), T200 (basal diet + 0.2 g Toyocerin¿/kg feed) and T1000 (basal diet + 1 g Toyocerin¿/ kg feed). The experimental diets contained a coccidiostat and were given ad libitum. No antibiotics were administered with the feed or water along the trial. Artificial insemination (AI) of does was performed 11 days (d) after kindling and kits were weaned at 35 d of age. Does, kits and feed were weighted at the beginning, AI, kindling, 18 d after kindling and weaning. Toyocerin¿ increased feed intake of lactating does, mainly between 18 d after kindling and weaning (P<0.05). When T200 was compared with T0 treatment, feed intake increased 76 g/d in the first cycle and 34 g/d in the second one. These increases allowed higher kit growth from 18th day to weaning and live weight at weaning (P<0.05). The weight of T200 kits was 43 g (4.9%) and 54 g (5.6%) higher than those of T0 kits in the first and second cycles, respectively. In the second cycle, Toyocerin¿ reduced kit mortality during the first 18 days of life from 18.5% with T0 to 11.1% with T200 and 9.9% with T1000 (P<0.05). Feed efficiency was not affected by treatments. No effects of Toyocerin level were observed on any recorded traits. The results of this experiment suggest that Toyocerin¿ can have a positive effect on productivity of rabbit does kept under an intensive system.