Laurent Boualit

Laurent Boualit
University of Lausanne | UNIL · Institute of Earth Surface Dynamics

PhD Student in Amphibian ecology under anthropogenic chemical pressure

About

11
Publications
3,997
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79
Citations
Introduction
I am a PhD student working on amphibians' ecology under anthropogenic chemical pressure. Trained as an ecologist at the University of Reims, France, I aim at studying the sublethal impacts of pesticides on amphibians' population using a multi-disciplinary approach.
Additional affiliations
November 2018 - present
University of Lausanne
Position
  • PhD Student
April 2018 - present
Université de Fribourg
Position
  • Technician
Description
  • I mainly care flies stocks, order lab's equipments and manage students works.
October 2017 - March 2018
Université de Fribourg
Position
  • Research Assistant
Description
  • Analyses of Capture Marque Recapture data in Tetrao urogallus in the purpose of understandings factors that impacts the population dynamic.
Education
September 2013 - July 2015
September 2010 - June 2013
Université de Reims Champagne-Ardenne
Field of study
  • General biology and science of earth and universe

Publications

Publications (11)
Article
Full-text available
Understanding the mechanisms underlying population decline is a critical challenge for conservation biologists. Both deterministic (e.g. habitat loss, fragmentation, and Allee effect) andstochastic (i.e. demographic and environmental stochasticity) demographic processes are involved in population decline. Simultaneously, a decrease of population si...
Poster
The research topic presented in the poster is about assessing the quality of the habitat of a polluted river in the north-western region of Algeria exposed to intensive agricultural activities and wastewaters discharges. For this purpose, we studied the physiological and biological responses of the snails Lymnaea stagnalis used as a bioindicator.
Poster
Full-text available
In this poster, we present our work on the impact of dejellying eggs prior to test 5 concentrations of Chlorpyrifos pesticide on X. laevis during 192 hours post fertilization. Our results suggest that in the case of Chlorpyrifos, the removal of jellycoat could increase the sensitivity of individuals regarding their size.
Article
Full-text available
Kin selection and dispersal play a critical role in the evolution of cooperative breeding systems. Limited dispersal increases relatedness in spatially structured populations (population viscosity), with the result that neighbours tend to be genealogical relatives. Yet the increase in neighbours’ fitness-related performance through altruistic inter...
Preprint
Full-text available
Understanding the mechanisms underlying biological extinctions is a critical challenge for conservation biologists. Both deterministic (e.g. habitat loss, fragmentation) and stochastic (i.e. demographic stochasticity, Allee effect) demographic processes are involved in population decline. Simultaneously, a decrease of population size has far-reachi...
Article
Full-text available
Dispersal is a central mechanism in ecology and evolution. Dispersal evolution is driven by a trade-off between costs and benefits, which is influenced by interindividual variability and local environmental conditions (context-dependent dispersal). Many studies have investigated how dispersal decisions may be influenced by environmental factors, in...
Preprint
Full-text available
Kin selection and dispersal play a critical role in the evolution of cooperative breeding systems. Limited dispersal dramatically increases relatedness in spatially structured populations (population viscosity), with the result that neighbours tend to be genealogical relatives. Yet the increase in neighbour performance through altruistic interactio...
Preprint
Full-text available
Dispersal is a central mechanism in ecology and evolution. Dispersal evolution is driven by a trade-off between costs and benefits, which is influenced by inter-individual variability and local environmental conditions (context-dependent dispersal). Many studies have investigated how dispersal decisions may be influenced by environmental factors, i...
Article
Full-text available
Dispersal is a central component of life history evolution. An increasing number of studies suggest that spatiotemporally variable environments may promote the evolution of "dispersal syndromes," consisting of covariation patterns between dispersal and morphological, physiological, behavioral, and life history traits. At the interspecifc scale, the...
Article
Full-text available
In the Northern Hemisphere, an increase in both the frequency and magnitude of violent flooding events has been reported due to climate change. According to life history theory, one might postulate that in ‘slow’ species: (i) environmental canalisation may act as a selective force that minimises to some extent adult survival variations caused by ca...

Questions

Questions (10)
Question
Hi everyone,
I am currently working with X. laevis and I would like to collect blood samples. This would happened right before euthanasia on anesthetized individuals. My aim is to measure testosterone level. Does anyone have any document/protocol to share ?
Best wishes,
Laurent
Question
Hello,
I'm looking for recent data on the use of fertilizers and pesticides in EU forestry. Would you know any EU website where I could find it ?
Cheers,
Laurent
Question
Hello,
Amphibians eggs are surrounded of a jelly coat constituted by one to several layers depending on the considered species. The composition of these layers depends on the considered layer and species. The functions of this layers are multiple. Indeed, the jelly coat is for instance known to be involved in fertilization, to avoid polyspermy, to act as a sperm chemoattractant and to play an important role of barrier against UV, infection and contaminants. But, the role of barrier against contaminants is not so clear. Indeed, the complex structure of the jelly coat provides to it an affinity to specific molecules. Therefore, certains molecules are stopped by the layers while others penetrate to the embryos.
In spite of this, most protocole for testing effect of toxicants on amphibians suggest to dejelly the eggs before the exposure. From my point of view, this recommendation lead to a loss of ecological relevance and I'm wondering if dejellying should not be reconsidered.
How about you ? Is there something that I don't see ?
Question
Hello,
I plan to measure AChE esterase on amphibians and I read that Butyrylcholinesterase can interfere in the measurement.
If I measure the transformation of Acetylcholine iodide, what am I measuring? Acetylcholinesterase activity or both acetyl- and butyrylcholinesterase activities ? Should I measure AChE activity with a BChE inhibitor for stating that I'm measuring AChE?
For me, I should but I've read a lot of articles that don't mention any use of the inhibitors, so I'm a bit confused.
Cheers,
Laurent
Question
Hi,
I'm currently doing a PhD in Switzerland. Swiss legislation on the euthanasia of laboratory animals just changed. Now, euthanasia of amphibian's larvae have to be done using liquid nitrogen. My problem is that I have then to measure molecular biomarkers and I don't know if it's possible after such a euthanasia method. Does anyone already tried it, maybe on fish?
Best wishes,
Laurent
Question
Hello,
I'm currently helping at writing a project on amphibians and the ethical commission is asking us how will we measure an emaciation of an individual according to our score-sheet. Weighing all individuals would be really time consuming and would probably stress them.
Does anybody faced this question ?
Question
Hi everybody,
I'm wondering if someone already tried to adapt the OECD Fish Embryo Acute Toxicity Test (FET) to Xenopus laevis embryos. I'd like to test the impact of certain pesticides on X. laevis embryos development and I think it would be a good way to adapt the FET.
Cheers,
Laurent
Question
Hi,
I'm wondering what molecular biomarkers can we get from amphibian saliva ? I'm sure we can get hormones but what else ?
Cheers,
Laurent
Question
Hi,
Do someone knows what primer(s) I could use for barcoding bacteria and protists ?
Question
How to deal with the small amount of plasma for measuring hormones level (testosterone and estrogen) in amphibians' eggs, larvae and post-metamorphs?

Projects

Projects (2)
Project
In this project, we aim at studying the impacts of antropogenic molecules on amphibians through a milti-level approach. Indeed, this taxon is suffering a decline and pollution conjugated to other factors such as habitat loss is known to participate to this decline. One of our main objectives is to link the individual-level effects to population dynamics.