Contrasting alterations in brain chemistry in a crustacean intermediate host of two acanthocephalan parasites

• Parasite-induced behavioral changes may rely on host adaptive behavioral flexibility
• Brain chemistry mediating flexibility may be altered in acanthocephalan-infected host
• Brain total protein is higher in intermediate host infected by two acanthocephalans (Bradford assay on brain extracts)
• Decreased antioxidant capacity and increased dopamine level is parasite species-specific (TEAC measurements on brain extract; UHPLC-ED on brain extracts for dopamine, serotonin and tyramine analysis)
• Species- and season-specific neurochemical changes reflect variable response of the crustacean intermediate host, Gammarus fossarum