DEL FRESNO PS, COLAUTTI DC, BERASAINGonadal development in pejerrey (Odontesthes bonariensis) during spawning season in relation with sex steroids and temperature variation in Gómez lake (Pampas region, Argentina).

DEL FRESNO PS; COLAUTTI DC; BERASAIN GE; MIRANDA LA

ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS.

ACAD BRASILEIRA DE CIENCIAS

Año: 2021 vol. 93 p. 1 - 13

0001-3765

Gómez lake (34 ° 39 ´S 61 ° 01´ W) is placed in the upper area of ​​theSalado river basin next to several lakes (Mar Chiquita, Carpincho and Rocha)with different degrees of connectivity to this river. The most abundant fish species in this lake is thepejerrey (Odontesthes bonariensis)valued due to the quality of its flesh and its attractiveness as a game fish.The aim of this study was to describethe gonadal stages of pejerrey during three consecutive spawning seasons(August to December) in relation with sexual steroids and temperature in thislake. In general, pejerrey gonadal development, the gonadosomatic indexand the plasma levels of estradiol and testosterone varied inrelation to air temperature. During the sampling period, pejerrey femalesstarted to ovulate in early August (winter), with a peak in October and endingin December with some of them with atretic oocytes. For males, it was possibleto find spermiating animals during the whole spawning season and some arrestedanimals only in December. Our results confirm the strong relationship withpejerrey maturation and temperature.