Assessment of phenotypic diversity within Goliath chickens population in Benin.

Goliath chickens are a new strain of poultry that originated in the department of Zou, commune of Agbangnizoun in the Republic of Benin. The characteristics of this chicken strain have not been well studied. The purpose of this study was to characterize the phenotypic diversity of Goliath chickens in departments of Zou and Couffo. A total of 140 birds made up of 92 females and 48 males were sampled using 18 morphological descriptors. The results showed a wide variation in plumage colour within overall population with the most dominant being black (18.57%), white (17.14%) and red (16.43%). Black (21.74%) and white (20.65%) plumage dominated in females and red in males (35.42%). Coloured beaks and shanks were common in both chicken sexes. Yellow eyes were more common in females (63.04%), while red eyes were the most prevalent in males (43.75%). Comb and wattle colours were red in both sexes. Morphometrically, sexual dimorphism is very marked most of the body measurements with male birds being significantly superior. The average body weight was 3.26 kg in males and 2.78 kg in females. The population was clustered in three morphotypes according to the gradient size. Chickens from Bohicon and Agbangnizoun on the one hand, and those from Zagnanado and Toviklin on the other, formed groups 1 and 2, respectively, while group 3 included individuals from Djidja. 77.96% of observed diversity was due to variation between individuals. Molecular characterization is recommended for a thorough knowledge of the Goliath chicken strain of Benin.