Effect of sexual dimorphism on phyenotypic traits in two-nigerian indigenous goat breeds at different ages

Abstract This study investigated the effect of breed and sex on linear body morphometric traits of 2-Nigerian indigenous goats. Eighty goats averaging 150 days old were purchased and used for the study at the Goat Production Unit, Livestock Section of the Teaching and Research Farm, Federal University of Technology, Akure, Nigeria over a ten-week period. Two treatments of five replicates at 3 and 5 goats per replicate totalling 15 and 25 West African Dwarf (WAD) and Red Sokoto (RS) goat breeds respectively. The treatment was divided into equal number of bucks to doe ratio at 30 WAD and 50 RS goats. Factorial experiment in completely randomized design arrangement was used for the study. Data on linear body morphometry were collected at different ages to determine the growth performances of the goats. The pulled data were used to analyse the goat breeds for relationship between body weight and linear body morphometric traits using SAS (2008) statistical software. Significant differences (p<0.05) in morphometric traits were observed between the breeds, sexes and interaction. The WAD goats significantly (p<0.05) demonstrated superior body weight (18.13kg) by week 10 than the RS (15.70kg). Red Sokoto goats exhibited significantly (p<0.01) higher height at withers (59.51cm versus 45.66cm) than WAD goats. Does were observed heavier than their buck counterparts. Strong, positive and significant (p<0.01) correlation (r=0.80) existing between body phenotypic traits of goats in this study showed that genes controlling these traits have linkage/pleiotropic effect. Regression analyses showed linear body traits singly or jointly well described the body weight of the goats owing to their significant (p<0.01) coefficient of determination values mostly ≥74%. Heart girth gave the best description of body weight in this study. The model becomes more accurate as more body parameters are included, indicating a better fit and higher accuracy of prediction. It is essential to prioritize the genes of both goat breeds for conservation and improvement through structured dietary, management and breeding programmes. Goat breeders can select heart girth to improve the body weight performance of their stocks.