0000000000114892
AUTHOR
Jean-philippe Troussard
Limiting immunopathology: Interaction between carotenoids and enzymatic antioxidant defences.
The release of reactive oxygen and nitrogen species (ROS and RNS) during the inflammatory response generates damages to host tissues, referred to as immunopathology, and is an important factor in ecological immunology. The integrated antioxidant system, comprising endogenous antioxidant enzymes (e.g. superoxide dismutase SOD, and catalase CAT) and dietary antioxidants (e.g. carotenoids), helps to cope with immune-mediated oxidative stress. Crustaceans store large amounts of dietary carotenoids for yet unclear reasons. While being immunostimulants and antioxidants, the interaction of these pigments with antioxidant enzymes remains unclear. Here, we tested the interaction between dietary supp…
Spines and behaviour as defences against fish predators in an invasive freshwater amphipod.
7 pages; International audience; Selective predation may be an important proximate cause of the success or failure of invader species. Gammarus roeseli is an invasive amphipod, for which the causes of establishment in rivers where the native species, Gammarus pulex, predominates remain unstudied. Freshwater amphipods are important prey for numerous fish predators, but empirical evidence of lower predation rates on exotic prey is scarce. In laboratory experiments, we compared the susceptibility of G. pulex and G. roeseli to fish predation, determined the mechanisms influencing prey selection, and studied the interaction between behavioural and morphological defences. Fish predators (brown tr…
Invasion de Dikerogammarus villosus (Crustacé, Amphipode) dans les eaux continentales françaises : dynamiques et conséquences
National audience
Differential expression and costs between maternally and paternally derived immune priming for offspring in an insect
1. When parasitized, both vertebrates and invertebrates can enhance the immune defence of their offspring, although this transfer of immunity is achieved by different mechanisms. In some insects, immune-challenged males can also initiate trans-generational immune priming (TGIP), but its expressions appear qualitatively different from the one induced by females similarly challenged. 2. The existence of male TGIP challenges the traditional view of the parental investment theory, which predicts that females should invest more into their progeny than males. However, sexual dimorphism in life-history strategies and the potential costs associated with TGIP may nevertheless lead to dissymmetric in…
Grape variety affects female but also male reproductive success in wild European grapevine moths
7 pages; International audience; 1. For insect herbivores the quality of the larval host plant is a key determinant of their fitness. Only little attention, however, has been given to the effects of plants on mating success of males and its consequence for the reproductive output of their mates. In addition, almost all the studies that have investigated the influence of host plants on herbivore fitness components have been done in the laboratory, and less is known of these effects in natural conditions. 2. Using the phytophagous European grapevine moth ( Lobesia botrana Den. & Schiff., Lepidoptera: Tortricidae), we tested the influence of grape cultivars as larval food on the probability of…