A total of 192 Californian×New Zealand rabbits weaned at 33 d old were used in this experiment. Animals were allocated at weaning to three homogenous treatment groups based on litter size and live weight. Rabbits in control treatment (C) were offered a standard feed (SF) containing Robenidin and Flavomycin. Rabbits in TI treatment were fed SF diet and supplemented between days 33 and 62 with Tiamulin. The third group of rabbits (RK treatment) were fed SF diet and supplemented with Rescue-Kit® (containing B. licheniformis and B. subtilis (1600×109 CFU), betain, vitamins and oligo-elements) in the drinking water from 41 to 50 d of age. Digestibility of the experimental diets was recorded from 47 to 50 d of age, growth performance from weaning to 77 d old and carcass performance at 77 d of age. In the second week after weaning, between days 41 and 50, average daily gain (ADG) and feed intake for the regime including Tiamulin increased by 19 and 7.5% (P≤0.051) compared to those fed C and RK treatments. In this period, animals supplemented with Tiamulin obtained the best feed conversion ratio (FCR) and the highest DM digestibility (P=0.023). Rabbits from RK treatment showed the same DM digestibility than those from the C group, but an intermediate FCR between TI and C rabbits. The retrieval of Tiamulin from the diet after day 62 and until day 77 led to a decrease in ADG of the rabbits, which was lower than for animals receiving RK (P=0.007), while C animals had intermediate growth traits. It resulted that for the whole fattening period, treatments had no effect on ADG, feed intake and FCR (32.1 and 143 g/d and 4.13 g/g, respectively). Overall mortality rates and dressing out percentage were also similar among treatments (26.6 and 59.8%, respectively).
additives; growth performance; rabbits