Fauna parasitológica de Zungaro zungaro Humeboldt e Valenciennes, 1821 provenientes da Amazônia Brasileira

Abstract

Zungaro zungaro is a fish that makes up the group of catfish and has the meat appreciated by consumers in different regions of Brazil. Investigations regarding parasites of fish of economic importance in the country have been prominent in the scientific environment, mainly because there are records of helminths that represent public health problems. Thus, in the present study, twenty-five fish of this species were captured along the Araguaia River from June to October 2015, by fishermen duly licensed to conduct three different surveys. The fish had gastrointestinal viscera, fins, eyes, gills, mucus, liver and spleen removed and stored in individual flasks with 10% formaldehyde to investigate helminths and ectoparasites with calculations of their respective percentages of infection. The parasites were collected with the help of a stereoscopic microscope and kept in Railliet & Henry liquid until identification. Three Hysterothylacium sp. Larvae were observed during the aniseed research. with an infection rate of 8%, mean intensity 1.5, abundance of 0.12 and variation of intensity of 1-2, being the first report of this helminth in Zungaro zungaro with calculations of infection indicators in the Tocantins-Araguaia basin. The larvae of Hysterothylacium sp.represent public health problems, lacking in-depth studies on their characteristics, requiring sanitary measures in post-slaughter management, as well as care in the discarding of viscera and in the preparation of food. During the study of helminths, twenty - three fish presented infection (92%), totaling 135 parasites collected from the stomach, intestine, vesicle, spleen and liver, with nematodes Cucullanus patoi, C. pseudoplatystomae, C. pinnai and Hysterothylacium sp. , Allocreadium sp., Monticellia siluri cestode and Sebekia sp. pentastomid, which presented infection rates of 12%, 24%, 28%, 8%, 76%, 24% and 8%, respectively. The research revealed the first record of the Monticellia siluri cestode in Zungaro zungaro and the trematódeo Allocredium sp. in pimelodida catfish in Brazil. In the course of the research about ectoparasitism, two fish had parasitism by Miracetyma piraya and Argulus sp. which resulted in 19 parasites recovered from Zungaro zungaro gills. The percentage of infection for both ectoparasites was 4% and the intensity 1 and 18 for Miracetyma piraya and Argulus sp.respectively. With the increase of the fishery in the Araguaia river, mainly in relation to the projects of implantation of net tanks, it is necessary to know the helminth species existing in this basin and the monitoring of the evolution of this parasitism in the native species, due to the high density which these species will be submitted.