The Female Reproductive System of Zearaja chilensis (Guichenot, 1848) (Chondrichthyes, Rajidae): Gametogenesis and Microscopic Validation of Maturity Criteria

Abstract

The female reproductive system of Zearaja chilensis (Guichenot, 1848) (Chondrichthyes, Rajidae). Gametogenesis and microscopic validation of maturity criteria. Int. J. Morphol., 33(1):309-317, 2015.SUMMARY: Chondrichthyans are extremely susceptible to overfishing due, among other things, to their reproductive adaptations. Basic knowledge of reproductive parameters is essential, both of ecological and for economic points of view. Zearaja chilensis is a valuable economic resource in South America. This work analyzes the microanatomy of female reproductive system, as well as the size of the onset of vitellogenesis. The material was fixed in Bouin and processed using routine histological techniques. Both ovaries are equally functional. Folliculogenesis depicts the same pattern of other Chondrichthyans. Follicles with different degrees of maturation coexist in mature animals, with the exception of oogonia, which were only found in immature individuals. Likewise, atretic follicles were recorded in all stages of maturation. The size of yolk input, microscopically recorded, is lower than the detected at naked eye. Oviductal glands and uterus show similarity with those reported in other lecitotrophic cartilaginous fish. This work reports, for the first time, the morfofunctional microanatomy of the species, and puts to the test the accuracy of the commonly employed criteria for the determination of sexual maturity, a critical data when determining management policies.

Morphological description of ovary and uterus of the nurse shark (Ginglymostoma cirratum) caught off at the Fortaleza coast, Northeast Brazil

“…The lining of the ovary identified in the nurse shark (Fig.3A) has the same morphological characteristics of the epithelium described for the ovary of the Zearaja chilensis (Wehitt et al 2015) and Sympterygia acuta (Díaz-Andrade et al 2009). Both species are oviparous and have the ciliated epithelium lining the ovary.…”

“…As recorded by Lutton et al (2005), granulosa cells of immature batoid Leucoraja erinacea may vary from simple to cubic form and while follicular genesis and oogenesis take progress the cells develop into a columnar structure. In G. cirratum, the morphology of vitellogenic follicles is similar to that described for S. acanthias (Gračan et al 2013), but different from Z. chilensis (Wehitt et al 2015) and D. bleekeri (Chatchavalvanich & Visuttipat 1997). These discrepancies can be attributed to the existing differences between sharks and rays (Dodd 1983).…”

“…The uterus of G. cirratum agrees with the general pattern described by for elasmobranch species. The morphological constitution of the uterine lining presents variations depending on the reproduction mode of elasmobranchs (Matthews 1950, Storrie et al 2009, Wehitt et al 2015. G. cirratum has secretory cells in the endometrium denoted by Alcian Blue staining (Fig.5B), indicating the production of mucopolysaccharides, even in immature individuals.…”

Morphology and Morphometry of the Ovaries and Uteri of the Amazonian Freshwater Stingrays (Potamotrygonidae: Elasmobranchii)

“…In all of the studied specimens, both ovaries contained the same ovarian components described in other elasmobranchs: germinal epithelium, ovarian stroma, oogonia cells and follicles at different stages of development, atretic follicle and corpus luteum (Hamlett et al, ; Díaz‐Andrade et al, ; Díaz‐Andrade et al, ; Serra‐Pereira et al, ; Galíndez et al, ; Wehitt et al, ; Pedreros‐Sierra et al, ).…”

Skate-ing on thin ice: molecular ecology of longnose skates in the Southeast Pacific Ocean

“…For Z. chilensis the ovaries initiate development of vitellogenic oocytes, indicative of maturity, when females reach 940 -1039 mm LT, whereas males mature at 760 -900 mm LT Oddone et al, 2005;Licandeo et al, 2006;Paesch & Oddone, 2008;Colonello, 2009;Quiroz et al, 2009;Bustamante et al, 2012;Colonello & Cortes, 2014;Wehitt et al, 2015). For D.…”