Impact of Helminth Parasites on Length-weight Ratio and Condition Factor of Fishes in Ajiwa and Jibia Reservoirs, Katsina State, Nigeria
Helminth parasites, length-weight relationship (LWR) and condition factor (K) of fishes in Ajiwa and Jibia reservoirs, Katsina State, Nigeria were investigated. From August 2016 to January 2017, 269 (136 O. niloticus and 133 C. gariepinus) and 242 (117 O. niloticus and 125 C. gariepinus) fish samples from Ajiwa and Jibia reservoirs respectively were randomly selected from the catches of the local fishermen and were observed for helminth parasites. The parasites were identified using relevant literatures. C. gariepinus recorded the highest prevalence of 34.59 and 43.2% in Ajiwa and Jibia reservoirs respectively compared to 21.3 and 29.91% in O. niloticus in Ajiwa and Jibia reservoirs respectively. Chi-square test revealed significant difference (p<0.05) between the Reservoirs and species examined. Length-weight relationship (LWR) and K factor of all individual fishes were determined. The regression coefficient “b” obtained was <3, thus indicating negative allometric pattern of growth in both species. There was strong positive correlation between the length and weight of the fish species (r>0.8). Condition factor (K) of infected and uninfected fishes indicated that the K factor of infected O. niloticus was slightly higher than the uninfected O. niloticus in Jibia resesrvoir. However, in other groups of fishes, the K factor of uninfected fishes was slightly higher than that of the infected fishes. The result also indicated that the K factor of O. niloticus in the two reservoirs was higher (K>3) than that of C. gariepinus (K<2). This however, indicated that O. niloticus performed better than C. gariepinus in the study areas.