Desempenho e mortalidade de láparos da raça Nova Zelândia Branco em ninhadas de diferentes tamanhos

The aim was to evaluate the performance and mortality of New Zealand White rabbits in litters of different sizes. Forty does were used, with an average age of 19 months (± 4.26), distributed in a randomized block design with five treatments (6, 7, 8, 9 and 10 suckling rabbits / litter) and eight replicates per treatment, each cage (doe + litter) constituting an experimental unit. The experimental period was 35 days, from birth to weaning. Every seven days, suckling rabbits were counted and weighed, from birth to weaning. The parameters adopted were: body weight of the doe, average number of suckling rabbits, average weight of the litter, total feed consumption, weight variation of the doe, mortality rate, weaning rate, weaned suckling rabbits / litter, weight gain of the litter and average weight of the weaned rabbit. There was a difference in treatments on the mortality rate (P <0.05), which was similar in litters with 6 to 8 suckling rabbits, reaching 21.67%, and higher for litters with 9 and 10 suckling rabbits, reaching 33.33%. The number of weaned suckling rabbits / litter was higher (P <0.05) for litters that started lactation with 8 or more suckling rabbits, with values ranging between 6.13 and 6.67. Even so, the birth weight of the suckling rabbits was lower (P <0.05) for litters with 9 or 10 animals, calculated values were 54 and 48g, respectively. In litters with 6, 7 and 8 suckling rabbits, birth weights were higher and similar to each other, corresponding to 69, 65 and 61g, respectively. Litters with up to 8 suckling rabbits have the highest birth weight, the best performance indexes during lactation and weaning, the lowest mortality rate and the smallest weight variation for the does.