Análise morfológica dos ovários e testículos de tubarões oceânicos capturados no Atlântico Sul e Equatorial

Detalhes bibliográficos
Ano de defesa: 2010
Autor(a) principal: RÊGO, Mariana Gomes do lattes
Orientador(a): EVÊNCIO NETO, Joaquim
Banca de defesa: EVÊNCIO, Liriane Baratella, OLIVEIRA, Paulo Guilherme Vasconcelos de
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal Rural de Pernambuco
Programa de Pós-Graduação: Programa de Pós-Graduação em Biociência Animal
Departamento: Departamento de Morfologia e Fisiologia Animal
País: Brasil
Palavras-chave em Português:
Área do conhecimento CNPq:
Link de acesso: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/4649
Resumo: This study aimed to evaluate the ovaries morphology and testes from oceanic sharks caught in the South Atlantic and Equatorial. For both samples were collected between January 2008 and March 2010, through the tuna fleet the vessels, captured along the South and Equatorial Atlantic, where they were collected 17 females and 164 males. In the vessels was removed visceral animals tract. After screening, the ovaries and testes were weighed and measured (length and width), identified macroscopically their maturational state. To perform the histological analysis of the material, the ovaries were fixed in 10% formalin sea water for 48 hours and testes in Bouin's fixative for 48 hours too. Then they were passed through the protocol histology. The microscopic analysis of ovaries was found three distinct maturational stages: Stage I (Immature), stage II (maturing) and stage III (mature). The first stage was classified immature ovaries; the second one was in five ovarian maturation and the third was nine ovarian mature. Immature females were found in ovaries with small width between 1.0 and 3.1 centimeters, with internal gelatinous structure or granules in maturing females, the ovaries were slightly higher showing varying width of 5.2 and 6.0 centimeters and mature ovaries had a width varying between 6.5 and 7.8 centimeters, with a rounded shape with large and well developed oocytes. On microscopic examination was observed that the ovaries are covered by epithelial tissue simple plan in the early stages of development, ranging for simple cubic in the final stages of maturation. Below the epithelium is the albuginea composed of dense connective tissue and regions of muscle fibers. In the initial stage of maturation, the ovaries presented epigone organ, they were not different histologically of the ovary. Now in the mature ovaries was shown a simple cubic epithelium, below the epithelium is a layer of dense connective tissue and muscle layer with the presence of vitellogenic oocytes and fat cells. It also showed a thin membrane enclosing the yolk oocytes. It was observed separating the pellucida zone of the oocyte from the follicle wall and a basal lamina between layers and granular teak layer. For the testes, of the 164 individuals collected, 52 were Isurus oxyrinchus, Carcharhinus falciformis 17 and 95 Carcharhinus longimanus. For the three species it was observed that the variation in the three maturation stages proposed had no visible morphological change. To characterize microscopic, cellular development in the three maturation stages, it also showed the same for all three species. The first stage was characterized by the presence of organ epigone that this phase is undifferentiated testis, thus presenting the same histological composition. The second stage there is a decrease in body epigone and differentiation of the testis with the emergence of the first germ cells (spermatogonia). The third stage the national epigone only present as a thin layer lining the testis, this is well developed and large seminiferous and the tubules with large amounts of sperm. In the classification of morphological testis there was a difference, once the species Isurus there was and Radial, for Carcharhinus was named as diametric.