Social context and chemical stress: investigating impacts on aging and reproduction in the turquoise killifish Nothobranchius furzeri

Details

Supervisors

Silvestre, Frédéric

Faculty

Faculté des sciences

Degree label

Master [120] en biologie des organismes et écologie, à finalité approfondie

Abstract

Senescence affects the entire biological processes of living beings. It is a difficult concept to study in vivo because it involves a longitudinal analysis across the entire life of organisms. Recently, Nothobranchius furzeri, the turquoise killifish, has been put forward as a model species for the study of aging. Its rapid life cycle adapted to its ephemeral natural environment results in a very short lifespan of four to six months. In this study, we explored the interaction between environmental factors, such as social context and chemical stress, with senescence and reproductive course in Nothobranchius furzeri. First, we investigated effects of the environment on the mortality and survival. Early exposure (0 to 7 days post hatching) to 100 μg/L of the neurotoxicant pesticide permethrin did not affect the survival of individuals. However, living in a community has a negative impact on the long-term survival of fish, which died on average 50 days earlier than individuals isolated from any social contact since their hatching. Second, we investigated the effect of the environment on reproduction. We evidenced that an early exposure to permethrin causes delayed effects on the reproduction of N. furzeri. At their 18th week post hatching, exposed individuals laid on average half as many eggs. Moreover, this experiment showed an effect of age on the reproductive capacities of this species. This study highlights the value of longitudinal measurements in defining multiple and delayed effects of the environment with aging and life history traits in the turquoise killifish, a short-lived fish.