INVESTIGADORES
MIRANDA Leandro Andres
congresos y reuniones científicas
Título:
Effects of climate change on pejerrey (Odontesthes bonariensis) reproduction
Autor/es:
MIRANDA LA; ELISIO M; CHALDE T
Lugar:
Buenos Aires
Reunión:
Simposio; 7th International Symposium On Fish Endocrinology; 2012
Institución organizadora:
7th International Symposium On Fish Endocrinology
Resumen:
Analysis of the mean
daily air temperature in Pampas region (Chascomús county) over the last 45 years
indicated an increase of 1.3° C. The aim of this research was to study how high
water temperature impairs the reproductive activity of an emblematic fish from
this region, the pejerrey Odontesthes bonariensis. Fish exposed at high water
temperature fluctuations (over 23 ° C) during few days quit spawning,
presenting clear signs of gonadal regression. At endocrine level, GnRH-I and
FSH-β in both sexes, LH-β and GPH-α in males and FSH-R, LH-R and cyp19a1a in
females decreased significantly in treated fish. Also, a strong reduction in
plasma sex steroid levels was found for both sexes. In vitro assays demonstrated that ovary functions are directly
disrupted by high temperature independent of the brain-pituitary axis, being
the inhibition of aromatase expression and consequently E2 synthesis
a primary effect provoking female reproductive impairment. Temperature increase
as consequence of global warming, coupled with the mechanism of
high-temperature sensitivity shown in this study, may be one of the reasons for
the decline in pejerrey populations observed in this region over recent
decades.