Caracterização morfológica e histopatológica de mixozoários e coccídios parasitos em Pygocentrus nattereri Kner, 1858, oriundos do município de Pracuúba, no Amapá.

Abstract

The Brazilian Amazon has the largest freshwater river basin in the world, and therefore also has a great diversity of fish, with an estimated richness of around 2,406 valid fish species. In this sense, the region has great fishing potential, being one of the main economic activities developed in the north of Brazil, especially in the state of Amapá, favored by its privileged geographical location. Another aspect is the high consumption of fish by riverside communities, which on average ingest 369g/day per person. Therefore, fish are sensitive to environmental changes, which may be caused by human or natural actions, causing ecological imbalance and the proliferation of various parasites, including myxosporidia and coccidia. These cause a series of diseases for fish, whether or not resulting in the death of the host and making them unsuitable for human consumption, with some parasites already described with zoonotic characteristics. The objective of this work was to describe morphological, morphometric aspects and histopathological changes caused by microparasites of Pygocentrus nattereri, captured in the sacaizal lake in the municipality of Pracuúba, in the state of Amapá. The specimens were transported dead to the Morpho-molecular Integration and Technologies Laboratory (LIMT) at the Federal Rural University of the Amazon (UFRA) in Belém, in the State of Pará, where they were necropsied. With the aid of a stereomicroscope, the specimens were examined in search of cysts and/or tissue fragments with signs of parasitism, with their presence confirmed through observation between the slide and coverslip under an optical microscope. Samples were fixed and processed for histology and scanning electron microscopy. According to the analyses, the presence of mature spores of cnidarians belonging to the Myxozoa class with morphology belonging to the genus Henneguya sp. and Myxobolus sp. and parasites of the phylum Apicomplexa Levine, 1970, of the genus Calyptospora sp. These studies contribute to understanding the parasites that affect fish in the Amazon region.