Last update: : Wednesday 28 September 2016, by
Par : Lea Briard, IPHC-DEPE
Date : Jeudi 29 septembre 2016 à 13h
Lieu : Amphithéàtre Marguerite Perey, bâtiment 01
Parasitism is a persistent challenge to the survival and reproduction of the latter, as it affects their health, daily activities, well-being, and nutritional state (Villalba et al. 2014). To combat parasitic infection, animals have developed immune responses that both disrupt parasite establishment and/or development (Coop & Kyriazakis 1999). Because animals have limited resources, it generates trade-offs in energy allocation between costly host responses to parasitism and other functions that are critical to host fitness (e.g., activity, growth, reproduction; Sheldon and Verhulst 1996). Animals have therefore evolved, in addition to physiological responses, behavioural strategies allowing them to suppress or prevent any internal unbalances, a phenomenon called behavioural homeostasis (Villalba et al. 2014). For instance, numerous species minimize the chances of infection by avoiding infested individuals or areas (Curtis 2014). Homeostatic behaviours can also be observed in livestock that respond to nutritional stress by modulating their food intake and selectivity in order to readjust internal balances (Villalba et al. 2014). Therefore, since animals had evolved mechanisms to reduce the chances of infection and can learn to avoid or prefer certain foods that enhance their fitness, they may also learn to ingest other substances in the environment such as natural medicines as they may also affect their fitness. There is growing evidence of self-medicated behaviours in domestic livestock in response to parasite infection (reviewed by Villalba and Landau 2012). Sheep, goats and cattle are the main target for these new investigations since they represent a tremendous proportion of worldwide livestock. Consequently, there is no study that investigates the existence of self-medicate behaviours in horses. As part of a project on parasitism and selective foraging in domestic horses, I did in vitro tests on gastrointestinal parasites to evaluate the toxicity of plants that were eaten by paratized horses during behavioural observations. During my presentation, I will present the results of these in vitro tests.
This project is made in collaboration with Eric Marchioni and Diane Julien-David from the chemistry deparment of the IPHC as well as Pr. Ermanno Candolfi and Julie Brunet (IPPTS, Strasbourg) and Jacques Cabaret (INRA, Nouzilly).