The study characterized the indigenous duck populations in three agro-ecological zones (AEZs) of Ghana using a primary phenotypic characterization approach involving observation and body measurement. Quantitative trait data were randomly collected on 414 matured ducks across three AEZs (138 from each AEZ). A 1:2 male-to-female selection ratio was used in each of the AEZs. Morphometric traits were subjected to analysis of variance with sex and agro-ecological zone as fixed factors using the General Linear Model. A simple and multiple regression analysis was used to estimate the relationship among morphometric traits to predict body weight. The results revealed that all morphometric traits were significantly influenced (p<0.05) by sex. Drakes were significantly superior (p<0.05) to ducks in the measured morphometric traits. A medium to high (0.593-0.945) positive correlation was observed among morphometric traits, with body length (0.894) as the best predictor of body weight. The discriminant analysis accurately classified 61.40% of ducks into their respective populations with cross-validation. The Mahalanobis distance was longer (2.27) between the Semi-deciduous and the Rain forest duck populations. The first principal component (PC1) extracted from factor analysis for the Semi-deciduous forest, Coastal savanna, Rain forest and the pooled principal component for all AEZs, explained the maximum variation among the populations with a corresponding total variance of 80.49%; 81.35, 82.93 and 80.59%. The PC1 had higher loadings on body weight (0.965), suggesting that body weight is the trait with the highest discriminatory power among the morphometric traits. A medium to high communality was observed for all morphometric characters measured, indicating that those traits could be used to explain the overall variability in the body dimensions of ducks.
ducks, morphometric diversity, quantitative trait, discriminant analysis, mahalanobis distance, variability