Abstract

One thousand two hundred and seventeen (1217) traditionally managed sheep comprising 491 West African dwarf (WAD) (154 males and 337 females) and 97 Yankasa (29 males and 68 females)  sampled over the Southwest Nigeria were used to assess allelic frequencies of qualitative trait loci based on defined genetic determinations in sheep. Traits investigated include wattles, ear size and attitude, eumelanin, coat spot, supernumerary nipples, head profile and horns.  Results showed that WAD and Yankasa sheep were similar respectively with regards to erect ear attitude (0, 0%), small ear size (0, 0%), horn (78.5, 84.7%), coat pigment (93.67, 93.45%) and supernumerary nipples (0.00, 0.00%), absence of coat spot (0.00, 0.00%).  Head profile was monomorphic (100%) but different in both breeds: straight in WAD and convex in Yankasa. WAD was standard for wattle, Wa*+, ear attitude EC*+, ear size EL*R and head profile, Te*cx (frequency=99.02). WAD exhibited higher degree of polymorphism than Yankasa especially for eumelanin type, and pigmentary pattern. However, the locus controlling head profile and ear attitude were monotypic; the frequency for a single class was higher than 75%.

Key words: Polymorphism, allelic frequency, genetic determination, WAD and Yankasa sheep.