INVESTIGADORES
MIRANDA Leandro Andres
congresos y reuniones científicas
Título:
Endocrine regulation of pejerrey (Odontesthes bonariensis) ovarian maturation throughout natural reproductive cycle
Autor/es:
ELISIO M; CHALDE T; MIRANDA LA
Lugar:
Buenos Aires
Reunión:
Simposio; 7th International Symposium On Fish Endocrinology; 2012
Institución organizadora:
7th International Symposium On Fish Endocrinology
Resumen:
Fish reproduction regulation is a complex process
involving the brain-pituitary-gonad axis and environmental cues. In this work,
it was studied pejerey ovarian maturation in correlation with the expression of
GnRHs, GtHs, GtH-Rs, cyp19a1b, cyp19a1a
genes and E2 plasmatic levels throughout natural reproductive cycle.
Primary growth stages were found when the day-length and water temperature were
maximum (summer) while cortical alveoli and the beginning of vitellogenesis stages
were observed when water temperature and day-length decreased (autumn-winter).
A major number of ovulated females were found when the temperature and day
length increased again (end of winter-spring) with temperature below 21° C.
Above this temperature atretic females were found. Low levels of E2 and
gene expression were associated with previtelogenic and atretic stages. On the
other hand, FSH-R, cyp19a1b, cyp19a1a and E2 levels were increasing during
vitellogenesis, while FSH-β expression remained high in all vitellogenic
stages. GnRH-I, GtHs and LH-R showed a significant increase
during late vitellogenesis and final maturation. These results suggested that pejerrey
vitellogenesis is controlled by FSH, stimulating aromatase and E2
synthesis, while final maturation is related with LH stimulation.