Augustine Naazie

Genetic diversity of Forest and Savannah chicken populations of Ghana as estimated by microsatellite markers

The characterization of indigenous animal genetic resources is a requisite step in providing needed information for the conservation of useful genotypes against future needs. Thus, in this study, 22 microsatellite markers were used to genotype 114 local chickens from the Forest (n = 59) and Savannah (n = 55) eco-zones of Ghana and the results compared to those of the ancestral red junglefowl (n = 15) and two European commercial chicken populations--a broiler (n = 25) and white leghorn (n = 25). A total of 171 alleles were observed, with an average of 7.8 alleles per locus. The local Ghanaian chickens showed higher diversity in terms of the observed number of alleles per locus (6.6) and observed heterozygosity (0.568) compared with the combined control populations (6.0 and 0.458, respectively). However, Wrights F-statistics revealed negligible genetic differentiation (F(ST)) in local Ghanaian chicken populations. In addition, 65% of the Savannah chickens were inferred to be more likely from the Forest, suggesting a south-north dispersal of chickens from their probable original location in the Forest zone to the Savannah areas. It is concluded that the Forest and Savannah chickens of Ghana are a single, randomly mating unselected population, characterized by high genetic diversity and constitute a valuable resource for conservation and improvement.

Phenotypic and genetic parameters for production traits of local chickens in Ghana

Summary Characterization of indigenous animal genetic resources is a first step in providing much needed information for the conservation and utilization of useful genotypes for future needs. The study was undertaken to estimate heritability of traits of economic importance in local chicken populations from the forest and savannah zones of Ghana. A restricted maximum likelihood animal model was applied to growth data of local chickens from hatch to 40 weeks to estimate heritability, phenotypic and genotypic correlations of body weight and shank length. Heritability, phenotypic and genotypic correlations were also calculated for egg number and egg weight. High genetic and phenotypic correlations were obtained between body weight and shank length. Average heritability estimates were 0.54, 0.42, 0.30 and 0.47 for body weight, shank length, egg number and egg weight, respectively. These moderate-to-high heritability estimates indicate that these traits could be targeted in genetic improvement programmes for local chickens.

Characterization of primary immune response in Ghanaian local, Sasso T-44 and broiler chickens to sheep red blood cell antigens

Animals should have the capacity to adapt to changing environmental pressures to ensure sustainable productivity. The easier an animal can adapt to disease burdens without extra cost to the farmer, the more profitable the enterprise becomes. Effective immune response protects organisms against disease insults and contributes to improved productivity. Primary immune response of Ghanaian local, Sasso T-44 and broiler chickens to sheep red blood cell (SRBC) antigens was measured 5 days post-inoculation. Antibody levels were determined by haemagglutination. Local ecotypes and Sasso T-44 chicken were superior to broilers in terms of their ability to respond to antigens. Female chickens produced more antibodies in response to increased concentration of SRBC antigens while the opposite was true in the male population. Further investigation of the genetic correlation between production performance and immune response of various chicken breeds will help establish the effect of, for example, high growth rate of broilers on their immunological status.