West African Dwarf goat populations of tropical rainforest zone: application of multivariate analysis tools on their...

This research was carried out to characterize the West African Dwarf (WAD) goats using multivariate approach based on their morpho-biometric traits in the tropical rainforest zone of Nigeria. Data on four physical qualitative traits, six morphology indicators, and nine morphological characters were generated from 279 goats. Descriptive statistics, non-parametric analysis and one-way approach of ANOVA with post hoc tests, discriminant analysis (canonical), principal component analysis (categorical), and regression tree analysis were employed to discern the effects of location and sex on the parameters, as well as characterize the goats. The frequencies of the qualitative traits show black coat color predominated (60.2%) over other coat colors, plain color predominated (75.3%) over other color patterns, straight horns (38.1%) predominate over other horn shape, and beard presence (66.7%) predominated over non-beard presence among the goats in terms of locations and sexes. Location and age were significantly affected on the biometric characters (p<0.05 and p<0.001) with goats from Enugu having higher values than other states, while only head length (HL) was affected significantly by sex (p< 0.05). The morphological indicators were not significantly affected by location and sex (p>0.05 and p>0.001), while age was significant. The discriminant analysis revealed a sparse, non-intermingling populations for the physical traits, biometric characters, and body indices implying they are different distinct populations from each other. Generally, the goat populations could be characterized using heart girth (HG), rump height (RH), and body weight (BW) due to the principal components, while the CHAID and Exhaustive CHAID algorithm analysis revealed BW and HL as the genetic classifiers of the WAD goats, both in terms of locations. Basically, the goats from the 3 locations appeared to be more homogeneous in nature, implying that a deployment of specific complimentary genomics work targeted at future selection and breeding programs to improve their productivity in the tropical rainforest of Nigeria is necessary.