Growth of suckled rabbit kits depending on litter size at birth

Standardization of litter size after birth is a common management practice used on broiler rabbit farms to optimize the growth intensity of kits in the litter. The aim of the present study was to evaluate the effect of the litter size at birth before the standardization performed on the subsequent growth intensity of suckled HYPLUS broiler rabbit kits. A total of 70 litters with a total of 639 newborn kits were selected for evaluation, while assessed litter sizes at birth covered 7 to 12 kits per litter. The assessed levels of litter sizes at kindling did not show significant differences in the average birth weight of the kits. Although the litter size was standardized to 8 kits for primiparous and to 9 kits for multiparous does on the first day after birth, the intrinsic litter size of does at kindling had a highly significant effect on the average live weight (LW) of 19-day old suckled kits (P <0.01). The average LW of kits at this age were higher in females which kindled 7 and 8 kits in litter compared to females in which the number of kits born in the litter was between 9 and 12. The same trend as in the case of LW was found for average daily gain values, while its higher values (P <0.01) were found in litters where does kindled only 7 and 8 kits per litter (19.1 and 17.9 g day-1 , resp.) in contrast to litters in which does kindled 9 to 12 kits per litter (14.0 to 15.4 g day-1). The performed standardization of litter size in the involved farm thus was not a sufficient management practice to reduce the variability of the average LW of suckled kits at 19 days of age.