A Comparative Study of the Gastro-Intestinal Helminth Parasites Infection of Fresh and Brackish Water Fishes from Warri River, Southern Nigeria

A comparative study of the gastro-intestinal helminth parasites infection of fresh and brackish water fishes from Warri river, Southern Nigeria, was undertaken. Eight hundred (800) fishes examined during the investigation belong to 30 families, 45 genera and 56 species. The study revealed a highly significant relationship (P < 0.001) between water type and gastro- intestinal helminth parasites infection of fish. Fresh water fishes recorded a higher infection rate of 38.11% than their brackish water counterparts with 17.85% rate of infection, suggesting a strong limiting influence of water type on gastro-intestinal helminth parasites infection of fish. However, in some other selected criteria, there were similarities in the pattern of infection of fish. On feeding habits, omnivorous fishes had the highest prevalence of helminth infection (49.55%) compared to predators, planktivores, herbivores and mud/silt feeders, in that descending order. Although euryhaline fishes were more susceptible to intestinal helminth infection than stenohaline fishes, the difference was not significant (P > 0.05). A seasonal pattern of helminth infection of fish was observed, with a high infection rate of 70.1% recorded during the dry season months of November to February and at low infection rate of 29.9% in the rainy season months of March to October.