Growth Characteristics of Six Reciprocal Crosses of Kenyan Indigenous Chicken

A study was carried out at the poultry research unit of the Kenya Agricultural Research Institute, National Animal Husbandry Research Centre, Naivasha in 1993 and 1994, to investigate growth performance of six reciprocal crosses of indigenous chicken originating from the Taita, Nyeri and Kericho districts in Kenya. Six hundred mixed sex day old chicks were used. Feed and water were provided ad libitum and the birds weighed individually on weekly basis up to the age of 30 weeks. Non-linear regression model procedures of the statistical analysis system (SAS) were used in data analysis. The gompertz growth model was used in fitting the body weight data with three parameter estimates, A, B and K. A statistical analysis of residual variations was used to determine differences between fitted curves. There were significant differences in growth pattern among the reciprocal crosses of indigenous chicken and between male and female birds. There was a possible effect of the choice of dam or sire in a given combination. The Nyeri line seemed to perform potentially better as a dam for both male and female offspring. The Taita line on the other hand, seemed to potentially perform better as a sire and so was the Kericho line. Use of growth data beyond 20 weeks resulted in better expression of asymptotic nature of fitted curves. There is some potential for improvement of the performance among indigenous flocks by judicious cross breeding strategies.