Heterosis for hatch weight and body weight gain in outcrossed native chickens of Nigeria under savanna conditions
The normal feathered (NF), frizzle feathered (FF) and naked neck (Na) native chickens of Nigeria were outcrossed under the savanna ecology. Eggs were collected and artificially incubated in electric type incubator. Chicks were weighed at hatch, identified and raised on a standard compounded ration. Body weight increase was evaluated at 4-20 weeks of age. Heterosis was evaluated for hatch weight and body weight at 20 weeks of age. Results revealed that percent heterosis ranged from -12.11to 1.66 and 1.93 to 12.80 for hatch weight and body weight at 20 weeks of age, respectively. The outcrosses using the NF as males had a higher body weight at 20 weeks of age. Consequently, the environmental limitation on growth impinged more on the NF than on the FF and Na genotypes. It was also noted that there is a greater divergence between the NF and the FF, the NF and Na than between the FF and Na birds. Outcrossing the NF birds with the FF and Na birds in the savanna may therefore improve body weight at 20 weeks of age in the outcrosses than in the respective straight bred genotypes.