Infestation of Copepods Parasite in the Gills of Economically Important Mugilidae Species from Lake Nokoue (Republic of Benin) and Lagos Lagoon (Nigeria)

Abstract

Parasitic copepods infect virtually all aquatic animal groups and show a staggering
diversity in body form and life cycle strategies infestation from Caligid copepods are
related to farmed fish populations in temperate zones, due to the economic costs they
represent and their higher incidence at high population densities such as those
occurring in aquaculture. However, only a few research examined copepod infestations
on wild fish populations or assemblages. Although the occurrence
of Lepeophtheirus species has been widely recorded on different fish species, the
characteristics and effects of infestation are poorly known hence this study. This study
aims to detect the infestation of parasitic copepod and analyze its relationships
according to season, sex and maturity on two fish species of Mugilidae (LF: Liza
falcipinnis and MC: Mugil cephalus). A total number of 1139 pieces of LF were
collected from Lake Nokoue and 1135 pieces of MC were collected from Lagos lagoon
between April 2019 and October 2021. They were examined for parasites in both dry
and wet seasons, results were analyzed using Chi-squared or Fisher’s Exact test.
The result obtained shows the highest total percentage of copepod prevalence was
found in Ganvie (86.23%) and the least in Djdje (63.14%). There is a significant
difference (P<0.05) in the rate of infestation of L. falcipinnis at Djdje to the other two
stations, there is a high prevalence of copepod parasites infestation in the Mugilidae
studied in the wet season than the dry season and sex did not impact the degree of LF
and MC infestation by parasites in the Lake Nokoue and Lagos lagoon.