Comparative Growth Performance of Common Carp (Cyprinus carpio) Cultivated in Different Altitudinal Temperature Gradients in Rwanda

Abstract

A 120-day experiment was conducted to compare growth performance of Common Carp at three agro-ecological zones of different altitude (low, middle and high elevation) in Rwanda. Fish juveniles of average body weight and length of 30.4±2.30 g and 14.4±1.34 cm, respectively were randomly distributed and stocked at 200 fish per 100-m² pond in each experimental site. Total weight gain (TWG), daily weight gain (DWG), relative growth rate (RGR), specific growth rate (SGR), and coefficient of condition (K_m) were calculated during the experimental period. Data were subjected to one-way analysis of variance. Results showed that fish reared at low altitude zone showed significantly higher (p ˂ 0.05) TWG, WG, RGR, and SGR compared to the middle and high-altitude groups. Nevertheless, growth of Common Carp was suitable in all three sampled agro-climatic zones of Rwanda. The DWG ranged from 1.16±0.03 g day^-1, 1.27±0.02 g day^-1, 1.62±0.02 g day^-1 and SGR ranged from 1.43±0.02 % day^-1, 1.50±0.01 % day^-1, 1.66±0.05 % day^-1 respectively for the high, middle and low altitude sites, hence the experimental carp fish had better growth performance records in these environments. The findings of this study demonstrated that Common Carp can could be cultured in all altitudinal gradients of Rwandan territory but
preferably in low elevation agro-ecological zones where better growth performance has been observed.