Fungal pathogen changes the feeding kinematics of larval anurans.
Pathogens can alter host life-history traits by affecting host feeding activities. In anuran tadpoles, keratinized mouthparts (teeth and jaw sheaths) are essential for feeding. Batrachochytrium dendrobatidis ( Bd ) is a pathogenic fungus of amphibians that can infect these mouthparts and reduce tadpole survival. However, the precise way that Bd-induced changes in tadpole mouthparts impact tadpole feeding is unknown. We use high-speed (500 frames/sec) videography to study how Bd-induced mouthpart deformities affect the feeding kinematics of Fowler's toad (Anaxyrus [= Bufo] fowleri ) and grey tree frog (Hyla chrysoscelis) tadpoles. We tested for species-specific patterns of Bd-induced mouthpart deformities to assess how deformations to specific areas of tadpole mouthparts alter feeding kinematics. The teeth of tadpoles from the Bd-exposed treatment slipped off of surfaces on which tadpoles graze and were in contact with an algal-covered substratum for a shorter duration in each gape cycle compared to teeth of control tadpoles. We also found that the jaw sheaths had significantly more deformations than labial teeth; however, how this relates to feeding kinematics is unclear. Our data show explicitly how Bd infection reduces foraging efficiency of anuran tadpoles by altering feeding kinematics and elucidate a mechanistic link between the pathogen infection and reduced host fitness.
Venesky
Matthew D
MD
Department of Biology, University of Memphis, Memphis, Tennessee 38152, USA. mvenesky@memphis.edu
Wassersug
Richard J
RJ
Parris
Matthew J
MJ
D000704:Analysis of Variance; D000821:Animal Feed; D000818:Animals; D001001:Anura / Q000382:microbiology / Q000502:physiology*; D001696:Biomechanical Phenomena; D008411:Chytridiomycota / Q000472:pathogenicity*; D056890:Eukaryota; D005247:Feeding Behavior / Q000502:physiology*; D007814:Larva / Q000382:microbiology / Q000502:physiology; D009055:Mouth / Q000473:pathology* / Q000503:physiopathology; D009181:Mycoses / Q000503:physiopathology / Q000662:veterinary*