Congo tetra4/6/2023 ![]() spilotus, and Potamorhina altamazonica, is characterized by lateral development of the flagellum, nuclear rotation, eccentric nuclear fossa formation, and chromatin compacted into thick fibers. Spermiogenesis in the curimatid species, Steindachnerina insculpta, Cyphocharax gillii, C. The results contribute positively to conservation studies of the species. orbignyanus present in the CEPTA / ICMBio intended for the gene bank responded to the reproductive process and presented viable gametes that allow the formation of juveniles. Considering the results we can conclude that specimens of B. This work was developed at the National Centre for Research and Conservation of Fish Continentals - CEPTA - ICMBio. orbignyanus kept in captivity, as grants to the programs in the conservation of the species. This descriptive study aims to evaluate the quality of sperm and artificial reproduction of B. Recently, this species was categorized as endangered of extinction by the “Red Book of Brazilian Fauna Threatened Species” due to overfishing, deforestation, pollution, changes in the hydrobiological regime the rivers, introduction of exotic species and environmental fragmentation. The piracanjuba Brycon orbignyanus is a species of fish at medium size that performs trophic and reproductive migrations and is very sensitive to environmental change. Os resultados contribuem positivamente para estudos de conservação da espécie. orbignyanus destinados ao banco genético responderam ao processo reprodutivo, possuindo gametas viáveis permitindo a produção de juvenis. O trabalho foi desenvolvido no Centro Nacional de Pesquisa e Conservação de Peixes Continentais – CEPTA – ICMBio. orbignyanus mantidos em cativeiro, como forma de aprimoramento da técnica de reprodução artificial com potencial uso em programas de conservação das espécies, que visem o processo de estocagem. Este estudo descritivo tem como objetivo avaliar a qualidade espermática e fertilização artificial da piracanjuba B. Atualmente, está categorizada como em perigo de extinção pelo “Livro Vermelho da Fauna Brasileira Ameaçada de Extinção”, devido principalmente à sobrepesca, desmatamento, poluição, mudança no regime hidrobiológico, introdução de espécies exóticas e fragmentação ambiental pela construção de barragens hidroelétricas, as quais interrompem rotas migratórias. The main advantages and drawbacks of fisheries and aquaculture are discussed.Ī piracanjuba Brycon orbignyanus é uma espécie de peixe de médio porte, realiza migrações tróficas e reprodutivas e é muito sensível às mudanças ambientais, como por exemplo, aquelas causadas pelo homem. Is based either entirely or partly on the capture of wild-caught specimens. Of marine fish species (n = 50) ranged from 0 to 3, implying that the production of all marine aquarium fish species (selective breeding programmes are used focusing on specific goals) and only three species at the level 0 (captureįisheries) and 1 (first trials of acclimatization to the culture environment). Of freshwater aquarium fish species (n = 50) ranged from 0 to 5, with 20 species classified at the level 5 Level to the hundred most popular aquarium fish species in Europe and North America. The main goal of the present study is to apply the concept of domestication ![]() Then, an increasing number of fish species Historically, all aquarium fish traded were wild-caught. ![]() The flagellar axoneme has a typical pattern (9 x 2 + 2) and the flagellum contains membranous compartments in the portion immediately posterior to the termination of the cytoplasmic canal.Īquarium fish trade has strongly increased in the past decades to become one of the most popular hobbies globally. The cytoplasmic collar surrounds the initial part of the flagellum, running in the cytoplasmic canal. In the short midpiece, several mitochondria and vesicles are unevenly distributed in the cytoplasm forming the cytoplasmic collar at the base of the nucleus. The nuclear fossa contain centrioles in perpendicular arrangement, surrounded by osmiophilic fibrous material. The head consists of a spherical nucleus with highly condensed chromatin and a centrally located electron lucent area connected to a moderate-sized nuclear fossa. The spermatozoon is of primitive type and exhibits characters typical for Type I aquasperm. Chromatin compaction proceeds during spermatid transformation within the spermatocysts as well as after spermiation within the lumen of the efferent ducts. Ultrastructural studies of spermiogenesis in Phenacogrammus interruptus using transmission electron microscopy revealed that the process is characterized by flagellum development, formation of a cytoplasmic canal, nuclear rotation, and nuclear fossa formation.
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