Characterization of the morphology of the three strains of oreochromis macrochir (boulenger, 1912) in Zambia

Author: 
Edwin Kikamba, Daniel Sikawa, Wilson Jere and Petros Chigwechokha

The study was conducted at Misamfu Aquaculture Research Station in Zambia to evaluate the morphology of three Oreochromis macrochir populations from Chambeshi, Kafue and Luapula rivers for recommendation to the species genetic improvement programme, as a prerequisite before a genetic improvement programme is undertaken. Body measurements were collected on 20 adult specimens of each population to study morphological differences among the three strains. Principal component analysis (PCA) for the three strains indicated no significant difference (p=0.351), with the first principal component (PC1), which is size, explained 59.7% of the variation while the second PC, which is the shape, explained 18.5 % of the variation. The variables that had high loadings on the second PC were PADC (80.7%), HED (73%) and VED (68.3%). Principal component analysis (PCA) of morphometric measurements between Chambeshi and Luapula indicated 75.2% of the variation was due to the first two components (PC1 [59%] and PC2 [16.2 %]). Analysis of variance on PC scores of PC2, whose shape, showed that there were significant differences (p=0.027) in shape between the two strains. The PCA between Chambeshi and Kafue indicated 82% of the variation was due to the first two components (PC1 [58.7%] and PC2 [23.3 %]). Analysis of variance on PC score of PC2 showed that the two strains were not significantly different (p=0.979) in shape. The PCA between Kafue and Luapula indicated 80.9% of the variation was due to the first two components (PC1 [61.8%] and PC2 [19.1%]). Analysis of variance on PC score of PC2 showed that the two strains were not significantly different (p=0.249) in shape. The study concluded that the Chambeshi with Kafue and, Luapula with Kafue strains were not significantly different in the measured parameters, while Chambeshi and Luapula differed significantly on the horizontal eye diameter, vertical eye diameter and the cheek depth, and therefore the observed differences could be attributed to geographical separation.

Paper No: 
4981