Gonadal development in pejerrey (Odontesthes bonariensis) during spawning season in relation with sex steroids and temperature variation in Gómez lake (Pampas region, Argentina)

DEL FRESNO, P. S.; COLAUTTI, D. C.; BERASAIN, G. E.; MIRANDA, L. A.

ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS.

ACAD BRASILEIRA DE CIENCIAS

Lugar: Rio de Janeiro; Año: 2021 vol. 93

0001-3765

Gómez lake (34 ° 39 ?S 61 ° 01? W) is a typical shallow lake of Pampas regionplaced in the upper area of the Salado river. The most abundant fi sh species in this lakeis the pejerrey (Odontesthes bonariensis) valued due to the quality of its fl esh and itsattractiveness as a game fi sh. The aim of this study was to describe for the fi rst timein this pejerrey wild population the gonadal stages during three consecutive spawningseasons (August to December) in relation with sexual steroids and temperature in thislake. In general, pejerrey gonadal development, the gonadosomatic index and theplasma levels of estradiol and testosterone varied in relation to air t emperature. Duringthe sampling period, pejerrey females started to ovulate in early August (winter), witha peak in October and ending in December with some of them with atretic oocytes. Formales, it was possible to fi nd spermiating animals during the whole spawning seasonand some arrested animals only in December. Our results confi rm the relationship withpejerrey maturation and temperature and can be useful for decision making in themanagement of this natural resource.