The Pathogen index in freshwater drum (Aplodinotus grunniens R.) from the usumacinta river in southeastern mexico (Aplodinotus grunniens R.) from the usumacinta river in southeastern mexico Pathogen index in freshwater drum from the usumacinta river

Abstract

Objective: Determine infestation rates and identify parasites in the fresh-water drum (Aplodinotus grunniens R.) from the Usumacinta River.

Design/methodology/approach: A total of 17 specimens were reviewed during the months of April-May 2022 and dissected in the Aquaculture Health Laboratory of Universidad Juárez Autónoma de Tabasco, Rios Di-vision, for the search and extraction of pathogens under conventional methods and techniques.

Results: Two pathogen groups were recorded and taxonomically classi-fied: Nematodes: larvae of Contracaecum sp. (n = 139) and adult Rhabdochona sp. (n = 9) and Trematodes: metacercaria of Aus-trodiposmotum sp. (n=19) and Clinostomum sp. (n=1). The larvae of Con-tracaecum sp. presented the highest infestation rates with a Prevalence (P) of 41.1%, Mean Intensity (MI) of 19.8, and Abundance (AB) of 8.1. The lowest rates were for the metacercaria of Clinostomum sp. with a P of 5.8%, MI of 1.0, and AB 0.05.

Limitations on study/implications:  From a parasitic zoonosis point of view freshwater drum is a potential disease vector due to the consumption of raw or undercooked fish.

Findings/conclusions: The parasitofauna recorded in freshwater drum from the lower basin of the Usumacinta River includes 4 species of para-sites belonging to two groups: Trematodes and Nematodes.