Parasitic Burden and Pathologic Effects of Anisakis Sp. (Nematoda : Anisakinae, Anisakidae) and Contracaecum Sp. Larvae (Nematoda : Anisakinae, Anisakidae) on Mugilids from Senegalese Estuaries

Abstract

Consumption of mugilids is widespread in Senegal, especially in the estuaries, where there production is of economic importance. The prevalence, mean intensity and pathologic effects of Anisakis sp. and Contracaecum sp. larvae which infected mugilids from Senegalese estuaries were investigated. In 2009, individuals of mugilids belonging to 6 and 5 species were trapped from the estuaries of Saloum, Senegal and Casamance rivers respectively. The prevalence and mean intensity of Anisakis sp. and Contracaecum sp. are higher in Senegal and Saloum estuaries respectively. The increase in the load of Contracaecum sp., related to the season in L. falcipinnis, the season, the size, the weight and/or the sex in M. cephalus from the estuaries of Saloum and Senegal and M. curema from Saloum estuary were due to an accumulation of parasites over time. Liver, kidney, body cavity and mesentery and ovaries are the respective sites of infection of Anisakis sp. and Contracaecum sp. larvae. The immune response observed is the formation of a fibrous capsule surrounding the parasites with melanin granules all around the capsule. The implementation of the capsule and the presence of melanin granules suggest the involvement of lymphocytes, monocytes, neutrophils and macrophages. The lesions caused by Anisakis sp. and Contracaecum sp. larval settlement in target organs may cause the death of the host and/or a reduction in fertility.