The effects of size of suckled litter on intake behaviour, performance and health status of young and reproducing rabbits

Abstract

We compared feed intake, performance and health status of females and their young reared in litters of 4 (group L4; n= 18) or 10 kits (group L10; n = 20) between 16 and 32 days of age. Between days 16 and 25, the individual milk intake was lower (-15.7%; P = 0.08) and the solid feed intake per kit was higher (+117%; P < 0.01) for the L10 than for the L4 litters. Between days 26 and 32 (weaning), milk and solid feed intake were similar among groups. Live weight of the young was 10% lower in the L10 than in the L4 group at weaning (P < 0.05) but was similar in both groups at 70 days of age. Mortality rate around weaning (16-42 days) was higher in the L10 than in the L4 group (29% vs. 17%; P < 0.05). Thirty-five days after parturition (day of slaughter), females showed a body condition and reproductive performance (conception rate, ovulation rate and litter size) which were similar in both groups, except for the weight of adipose tissues which was 35.8% lower in the L10 females (P < 0.01). These results suggest that the growth and survival of young rabbits are weaker if the rabbits are reared in large-sized litters in spite of an earlier and higher solid food ingestion which only partially compensates for the low milk availability.