This study aimed to evaluate the effect of the stage of feed restriction during pregnancy on performance and productivity of young rabbit does. Thirty New Zealand white female rabbits of 20 weeks of age (first kindling) and weighed 2800 ± 100 g were randomly divided into three groups. Group 1 (control group): rabbits were provided daily with 185 g of food increased to 200 g from the 15th day of gestation (daily food intake of pregnant does according to 19). Group 2 (R1, early feed restriction): rabbits were offered daily a restricted amount of food (60 % restriction, 111g) for the first half of pregnancy (the first fifteen days) then offered 200 g of food daily till parturition. Group 3 (R2, late feed restriction): rabbits were provided with 185 g of food daily through the first half of pregnancy then offered daily a restricted amount of food (60% restriction, 120 g) for the second half of pregnancy. Treatments started after natural mating. After parturition, all does and their young were provided ad libitum amount of feed till weaning. Does were weighed individually at the start of the experiment then every two weeks and just after kindling. For each doe, the living pups were weighed to obtain the total litter weight and the mean pup weight at birth. Then pups were weighed at 21 days of age and at the day of weaning (the 30th day). Five days after kindling, two blood samples were taken from each female, one for determination of the hematological parameters and the other for separation of serum for determination of prolactin and serum protein concentration. The results of this study revealed that, feed restriction during the first half of gestation did not affect maternal body weights, litter size, litter weight or mean pup weight at birth as compared to the control group. Whereas feed restriction during the second half of gestation was accompanied with significant reduction in the weights of does at the 4th week of pregnancy and at kindling. This decrease became non significant from the second week after kindling till the end of the experiment. The litter weight at birth and the individual weaning weight of R2 were significantly reduced. The highest mortality was recorded in pups of R2. No significant differences in blood parameters or serum prolactin were observed between the control and feed restricted groups. The total protein was significantly reduced in serum of R2 group. It is concluded that, in order to reduce the excessive fatness of young rabbit does, restricted feeding during the first half (the first two weeks) of gestation is recommended. |
