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Structural and ultrastructural characteristics of the yolk syncytial layer in Prochilodus lineatus (Valenciennes, 1836) (Teleostei; Prochilodontidae)
(Zygote, 2007-08-01) [Artigo]
The yolk syncytial layer (YSL) has been regarded as one of the main obstacles for a successful cryopreservation of fish embryos. The purpose of this study was to identify and characterize the YSL in Prochilodus lineatus, ...
Spermiogenesis and spermatozoa ultrastructure in Salminus and Brycon, two primitive genera in Characidae (Teleostei : Ostariophysi : Characiformes)
(Acta Zoologica, 2006-10-01) [Artigo]
In Salminus, spermiogenesis is cystic and gives origin to a type I aquasperm. Spermatid differentiation is characterized by chromatin condensed into thick fibres, nuclear rotation, nuclear fossa formation, cytoplasmic ...