Hetrosis of Early Growth Performance in Three Breeds of Rabbits (Oryctolagus cuniculus)

P. E. Nwakpu; C. C. Ogbu; Ugwu S. O. C.

The study investigated heterosis effects for early growth performance using three popular breeds of rabbits in Nigeria (Chinchilla, New Zealand White and Dutchbreeds). Thirty six (36) sexually mature rabbits belonging to three genetic groups (Twelve per breed at the mating ratio of three males to nine females) were employed for the study. Matings within each breed were carried out to generate purebred progenies. These were reared and monitored for growth performance from birth to 32 weeks of age (age of sexual maturity). At 32 weeks of age, 3 males and 9 females each of the three breeds were randomly selected from their respective groups and used in cross breeding in a ratio of one Buck to two does. F1 crossbred progenies were reared according to crossbred groups to weaning (8 weeks of age). The bioeconomic traits considered in this investigation for the purebreds and F1 crossbred groups were; individual kitten weight at birth and at bi-weekly intervals up to 8 weeks of age; individual kitten weight at weaning; litter size at birth and at weaning sex-ratio, pre-weaning mortality and estimates of heteroses. Data collected were subjected to Analysis of Variance to test for the effect of breeding groups on parameters measured. Comparison between crossbred and purebred groups was done using independent samples (T-Test), while significance of heterosis was performed using one-sample T-Test. All analyses was performed using the Statistical Package for Social Sciences (SPSS) Version 17.0 (2007). Significant means were separated using the Duncans New Multiple Range Test in SPSS. Results showed that the crossbred kits were heavier in weight (g) than the purebred kits from birth to weaning (45.39g from Nzw x Nzw to 48.35g from CH x CH among the purebreds and 38.25g from Nzw x CH to 55.50g from D x CH) for the crossbreds at birth; and rose to 420.14g from D x D and 569.38g from CH x CH) among the purebreds to 670.63g from Nzw x CH and 704.41g from Nzw x D) for the crossbreds. The result of the reproductive performance of the breeds indicated lack of significant (P>0.05) differences except in the preweaning mortality of the purebreds and the litter size at weaning (LSW) among the crossbreds. Litter size at birth (LSB) were (on average) lower for the purebreds than the crossbreds. Estimates of direct heterosis for body weight were all positive and favorable for the crossbred kits except (Nzw x CH) crosbred kits. Positive heterosis for litter size at birth ranged from 14% to 26% and 14% to 50% for litter size at weaning among the crossbred kits. Within litter mortality in Nzw x D and Nzw x CH crosses were negative but increased and were positive among the D x CH crossbred kits. The potential of crossbreeding to tap the non-additive genes for reproductive performance was confirmed in the present study. Crossing (Nzw x CH) and (Nzw x D) resulted in positive heterosis for body weight, while (D x CH) helped to improve preweaning mortality and litter size.

Select Volume / Issue:

• Volume 3,Issue 6, May 2015

Year:

2015

Type of Publication:

Article

Keywords:

Growth Performance; Breeds of Rabbits; Heterosis; Genetic Groups; T-Test

Journal:

IJAIR

Volume:

3

Number:

6

Pages:

1793-1799

Month:

May