Effect of Genetic Drift versus Natural Selection on Clutch Traits in Two Populations of the Nigerian Local Chickens

Abstract

The study was carried out at Akpehe poultry farm, Makurdi,on the Tiv and the Fulani Nigerian local chicken ecotypes.The variability on clutch traits were estimated on 540 hens produced from the mating of 40 hens and 4 sires each for the Tiv and the Fulani local chicken ecotypes, randomly selected from rural populations. The hens were housed singly and hand mated. Daily egg production was recorded individually. The data was organized according to clutch size, clutch number, pause number and pause length. SAS procedure was used to analyze the variability on clutch traits within and between the ecotypes.Clutch size has the highest variability within the ecotype. Between the ecotypes, the Tiv ecotype showed higher variability in clutch traits than the Fulani ecotype. The higher variability in the Tiv ecotype was related to the large population of single inter breeding flock which renders genetic drift insignificant. The small reproductive population often left when the Fulani women disposed large numbers of matured birds from their flock when preparing for new settlements thereby accelerating genetic drift. This had driven the population of the Fulani ecotype towards genetic uniformity in clutch traits by reducing genetic variation overtime. The genetic diversity of the Fulani ecotype in clutch traits that could be used for current and future adaptation is been threatened.