Assessing the Diversity of Metazoan Parasites of Sarotherodon melanotheron (Cichlidae) from Inlands Waters in Southern Benin (West Africa)

Abstract

Aims: This paper presents a snapshot of the metazoan parasite fauna of Sarotherodon melanotheron collected from two stations across lake Nokoué.
 Study Design: Fish samplings were done at the landing stage of Lake Nokoué (sampling site 1) and Tota (sampling site 2) from october 2016 to march 2017. Water physicochemical parameters such as pH, salinity, temperature, and conductivity were measured monthly. 
 Methodology: A total of 246 specimens of Sarotherodon melanotheron comprising 149 males and 97 females were investigated. Size and weight were measured. Then,fish were dissected and parasites were checked in several organs. Collected parasite were identified using adequate keys of identification. The chi square test was used to compare the prevalence of different parasite groups whereas Student T-test was applied to assess difference between parasite mean abundance within the two sampling stations. The pearson correlation coefficient was used to appraise possible influence of water parameters on parasite prevalence.
 Results: The total prevalence was 86.58%. Eight parasite species were collected belonging to Myxosporidia, Monogena, Digena, Cestoda, Acanthocephala and Copepoda. Epidemiological parameters were calculated in order to appreciate the diversity of the parasitofauna according to sampling site, sex, and fish size. Females were significantly more infected than males (χ2 = 10.093; p < .05). Among the parasites, only monogenean prevalence (41.46%) was significantly different (χ2 = 149.645; p < .05). Correlation between physicochemical parameters and the prevalence of parasite groups showed that monogenea and cestoda were the most abundant in rainy season in opposite to the Digena that are mainly recorded in the dry season.