Data/hora: 06/06/2024 11:57:34

Provedor de dados: | 19
País: | Japan
Título: | The Pattern of Ovarian Development in the Prepubertal Antarctic Minke Whale (Balaenoptera bonaerensis)
Autores: | TETSUKA, Masafumi; ASADA, Masatsugu; MOGOE, Toshihiro; FUKUI, Yutaka; ISHIKAWA, Hajime; OHSUMI, Seiji; 手塚, 雅文; 福井, 豊.
Data: | 2004
Ano: | 2004
Palavras-chave: | Whale; Minke whale; Ovarian development.
Resumo: | This study describes the morphological and morphometrical changes associated with prepubertal ovarian development in the Antarctic minke whale (Balaenoptera bonaerensis). Ovaries were harvested from 94 immature minke whales caught in the Antarctic Ocean during the summer feeding season (December-March). Notable differences in ovarian size and morphology were found among animals. Up to 10 folds difference in ovarian weight was found among prepubertal whales of similar body size. During the prepubertal period, ovaries grew slowly and approximately doubled their weight. The morphologies of right and left ovaries were almost identical while the growth of the ovary appears to occur preferentially on the right side. The most striking morphological feature was numerous small antral follicles less than 5 mm in diameter found in ovaries of younger immature whales. The occurrence of these ovaries was highest in whales less than 6 m long and gradually decreased as body length increased. In larger whales, the occurrence of ovaries with a smaller number of follicles up to 10 mm and thick tunica albuginea increased. Thus, the ovary of the Antarctic minke whale experiences bursts of small follicular development during the early prepubertal period before becoming a more developed ovary with fewer but larger follicles, and thick tunica albuginea.
Idioma: | Inglês
Identificador: | http://ir.obihiro.ac.jp/dspace/handle/10322/3034
Editor: | 日本繁殖生物学会
Formato: | application/pdf
Fonte: | 日本繁殖生物学会