Michele Velasco1, Jhonata Eduard2, José Ledamir Sindeaux Neto3, Lilian de Nazaré Santos Dias4, Edilson Matos5, Evonnildo Costa Gonçalves6. 1. Universidade Federal Rural da Amazônia - UFRA, Campus Belém, Av. Presidente Tancredo Neves, 2501, Belém, PA, 66.077-901, Brazil. michele.velasco@ufra.edu.br. 2. Programa de Pós Graduação em Aquicultura em Recursos Aquáticos Tropicais, Universidade Federal Rural da Amazônia, Belém, PA, Brazil. 3. Universidade Federal Rural da Amazônia, Campus Belém, Belém, PA, Brazil. 4. Universidade Federal Rural da Amazônia, Campus Paragominas, Paragominas, PA, Brazil. 5. Laboratório de Pesquisa Carlos Azevedo, Universidade Federal Rural da Amazônia, Belém, PA, Brazil. 6. Laboratório de Tecnologia Biomolecular, Universidade Federal do Pará, Belém, PA, Brazil.
Abstract
PURPOSE: Members of the genus Kudoa Meglitsch, 1947 are known to infect the muscles of commercially important fishes worldwide, including those in the order Siluriformes. This paper describes the occurrence of a new species of Kudoa in the catfish Brachyplatystoma rousseauxii based on morphological study and molecular analysis of the ribosomal RNA gene (SSU rDNA). METHODS: Fifteen specimens of Brachyplatystoma rousseauxii were purchased from fishing zones near Mosqueiro Island, Belém, Pará, Brazil. After necropsy, tissue samples and cysts were analyzed using a stereomicroscope, and fresh slides were viewed under a light microscope to confirm parasitic infection. The tissue fragments were removed and processed for molecular and histological analyses. RESULTS: Microscopic pseudocysts were found in the epaxial region of skeletal muscle fibers in 80% of the analyzed specimens. The myxospores were quadrangular with four shell valves (SV), pyriform polar capsules (PC), and internal symmetry. Phylogenetic analyses indicated that the new species formed a cluster with the species previously described in the Amazon, being close to two freshwater species. CONCLUSIONS: Morphological differences and molecular data of SSU rDNA support that Kudoa rousseauxii n. sp. is a new species that infects B. rousseauxii, a freshwater fish with intense migratory cycles that is widely captured and consumed in the Amazon.
PURPOSE: Members of the genus Kudoa Meglitsch, 1947 are known to infect the muscles of commercially important fishes worldwide, including those in the order Siluriformes. This paper describes the occurrence of a new species of Kudoa in the catfish Brachyplatystoma rousseauxii based on morphological study and molecular analysis of the ribosomal RNA gene (SSU rDNA). METHODS: Fifteen specimens of Brachyplatystoma rousseauxii were purchased from fishing zones near Mosqueiro Island, Belém, Pará, Brazil. After necropsy, tissue samples and cysts were analyzed using a stereomicroscope, and fresh slides were viewed under a light microscope to confirm parasitic infection. The tissue fragments were removed and processed for molecular and histological analyses. RESULTS: Microscopic pseudocysts were found in the epaxial region of skeletal muscle fibers in 80% of the analyzed specimens. The myxospores were quadrangular with four shell valves (SV), pyriform polar capsules (PC), and internal symmetry. Phylogenetic analyses indicated that the new species formed a cluster with the species previously described in the Amazon, being close to two freshwater species. CONCLUSIONS: Morphological differences and molecular data of SSU rDNA support that Kudoa rousseauxii n. sp. is a new species that infects B. rousseauxii, a freshwater fish with intense migratory cycles that is widely captured and consumed in the Amazon.
Authors: R Reimschuessel; C M Gieseker; C Driscoll; A Baya; A S Kane; V S Blazer; J J Evans; M L Kent; J D W Moran; S L Poynton Journal: Dis Aquat Organ Date: 2003-02-13 Impact factor: 1.802