ESTIMATION OF GENETIC DISTANCE USING PHENOTYPIC TRAITS IN DONKEYS

Résumé

Donkey breeds represent a fascinating model of domesticated biodiversity. This study was conducted in the Sahel agro-ecological zone of North Eastern part of Nigeria in Borno and Yobe State. Two hundred matured (200) donkeys were sampled from donkey owners in parts of Borno and Yobe States and were used for the study. The animals were maintained under the traditional system of management. The body measurements evaluated include: Face length (FL), Distance between the ears (DBE), Ear length (EL), Neck length (NL), Height at withers (HW), Body length (BL), Tail length (TL) and Body weight (BW). Body weight and body measurements were measured using a specially designed tape (WE BO MALEBAND®) graduated from 0 meters to 2.26 meters (0 - 226cm). Body weight was estimated by taking readings round the circumference of the chest girth. The estimation of genetic distance using phenotypic data were analyzed using Multivariate analysis (Quadratic discriminants analysis) using MINI TAB statistical package version 16. The percent classification of donkeys investigated that the Grey (Idabari) donkey had the highest categorization rate of 94.4% while the others had lower classification percent. The highest classification percent may have indicated that the Grey breed varied significantly in the study areas while the lower percent classification may have indicated that the populations of donkeys in these groups are more comparable. The donkeys in the study area were categorized into four breeds on the basis of coat colour as Grey (Idabari), Red/rust (Auraki), Black (Duni) and White (Fari) with the grey breed being more significant varies than the other ecotypes as revealed by the genetic distances. The white (Fari) donkey had the shortest genetic distance as compared to the other breeds, suggesting that this breed is more unified.