PHENOTYPIC AND MORPHOLOGICAL CHARACTERIZATION OF INDIGENOUS GHANAIAN RABBIT (ORYCTOLAGUS CUNICULUS) RESOURCES IN NORTHERN GHANA

Abstract

The aim of this study was to characterize phenotypically, indigenous Ghanaian rabbit resources of northern Ghana. When characterization of the indigenous rabbits is complete, selection and breeding for specific objectives can be systematic. Three hundred local rabbits from the three northern regions of Ghana were randomly sampled. Frequencies for colour varieties were computed. The effects of variety, region and sex on body measurements were analyzed and phenotypic correlations between various body measurements were estimated. Regression equations were also fitted for body weight using body measurements. Thirteen colour varieties were identified: White, Red, Black, Brown, Ash, Black White, Brown White, Black Brown, Red Brown, White Red, White Ash, Ash Brown and Black Brown White. The White colour variety had the largest representation (28.0%). The least represented were the Black Brown (0.3 %) and Ash Brown (0.3 %). The overall mean body weights for the top six colour varieties were: Brown (1.80 ± 0.095 kg), White (1.63 t 0.084 kg), Brown white (1.52 ± 0.110 kg), Black white (1.48 ± 0.132 kg), Black (1.43 ± 0.157 kg) and Red (1.43 ± 0.146 kg). Rabbits from the Upper West region had much higher body weights than Rabbits from the Northern and Upper East regions. Cases of genotype environment interaction were observed. The effect of variety was a significant (p<0.05) source of variation for body length, heart girth, shoulder-to-tail drop and tail length. The effect of region was highly significant (p<0.01) source of variation for body weight, body length, heart girth, shoulder-to-tail drop, ear length, tail length and head-to-pubic length. Sex was a significant (p<0.05) source of variation for body length, heart girth, shoulder-to-tail drop and head-to-pubic length. The effect of breed was a highly significant (p < 0.01) source of variation for all ii www.udsspace.uds.edu.gh morphometric traits except tail length. Region * colour variety interaction influenced (p < 0.05) body weight while colour * sex interaction exerted effect on ear length (p < 0.05) and tail length (p < 0.01). None of the morphometric traits was influenced (p > 0.05) by interaction effects of the fixed factors. For carcass characteristics, the effect of variety was not significant (p > 0.05) for all parameters measured. The effect of sex was a highly significant (p<0.01) source of variation for hot carcass dressing percentage and intestine (empty) weight. Cold carcass dressing percentage and liver weight were also influenced (p < 0.05) by sex. The males had higher (p<0.01) hot carcass dressing percentage (50.57± 0.491) than the females (47.431± 0.556) and higher (p<0.01) cold carcass dressing percentage (47.04± 0.641) than the females (44.56± 0.677). Rabbits lost about 3% of their live body weight after bleeding. The edible internal organs (lung, heart, liver and kidneys) constituted 4.92 % of the live body weight of the rabbit. Heart girth had the highest correlation coefficient with body weight (0.663; p<0.01). There was positive moderate to high correlation between the various body measurements. The highest correlation was between head to pubic length and shoulder to tail drop (0.839; p < 0.01). The best weight prediction equation was given by heart girth, followed by shoulder-to-tail drop/body length, head-to-pubic length and thigh length, with the poorest being leg length, tail length and ear length. Average of 3 kindles per doe was recorded over 9 months. Litter size ranged between 1 to 5 kits in the first kindle (parity) in all the regions. It however increased to between 1 to 8 kits in the second and third parity (kindle). Region had significant effect (p < 0.05) on birth weight during the first kindle, both weaning weight and birth weight in the second and third kindles, but had no significant effect (p > 0.05) on