CCT CONICET - PATAGONIA NORTE   21812
CENTRO CIENTIFICO TECNOLOGICO CONICET - PATAGONIA NORTE
Centro Científico Tecnológico - CCT
Rainbow trout adaptation to a warmer Patagonia and its potential to increase temperature tolerance in cultured stocks
BECKER, LEANDRO ANÍBAL; CRICHIGNO, SONIA ALEJANDRA; ORELLANA, MABEL; MIRENNA, GUILLERMO; LARRAZA, RODRIGO; BATTINI, MIGUEL ANGEL; CUSSAC, VÍCTOR ENRIQUE
Año: 2018 vol. 9 p. 82 - 82
The viability of rainbow trout Oncorhynchus mykiss (Walbaum, 1792) culture is being challenged progressivelyby global warming. Previous trials with Australian and Japanese rainbow trout lines suggested that improvementsin thermal performance may be possible. Here, we hypothesized that strain-related differences in physiologicalresponse to temperature exist between a north Patagonian hatchery stock (CENSALBA), a Neotropicalone (Criadero Boca de Río), and a thermal stream (Valcheta) population of wild introduced rainbow trout. Thiswas tested by comparing, at 20 °C, the thermal preference, specific metabolic rate, thermal tolerance, growth,and condition on juveniles of the three strains, and on a Valcheta stream male x CENSALBA female F1 cross.Preferred temperature (PT) and loss of equilibrium temperature (LET, a measure of thermal tolerance) ofValcheta stream and F1 were significantly higher than those of CENSALBA, and the average PTs of Valchetastream and F1 were higher than the 95% confidence interval of available reference data for rainbow trout. Theseresults suggest that the F1, reared under standard hatchery conditions and selected by growth and thermalpreference, presents higher thermal preference and higher thermal tolerance than the current CENSALBAhatchery stock. Introduction of this naturally adapted strain to hatchery stocks would likely result in the improvementof their temperature resistance to warmer waters. Current studies on adults of this F1 generation areunderway.