Plasticity of immunity in response to eating.
Following a meal, an animal can exhibit dramatic shifts in physiology and morphology, as well as a substantial increase in metabolic rate associated with the energetic costs of processing a meal (i.e. specific dynamic action, SDA). However, little is known about the effects of digestion on another important physiological and energetically costly trait: immune function. Thus, we tested two competing hypotheses. (1) Digesting animals up-regulate their immune systems (putatively in response to the increased microbial exposure associated with ingested food). (2) Digesting animals down-regulate their immune systems (presumably to allocate energy to the breakdown of food). We assayed innate immunity (lytic capacity and agglutination) in cornsnakes (Pantherophis guttatus) during and after meal digestion. Lytic capacity was higher in females, and (in support of our first hypothesis) agglutination was higher during absorption. Given its potential energetic cost, immune up-regulation may contribute to SDA.
Department of Biology, Georgia Southern University, Statesboro, GA 30460, USA University of Georgia College of Veterinary Medicine, Athens, GA 30602, USA.
Rachel L
RL
Luoma
Department of Biology, Lafayette College, Easton, PA 18042, USA.
Michael W
MW
Butler
Department of Biology, Georgia Southern University, Statesboro, GA 30460, USA Department of Biological Sciences, University of the Pacific, Stockton, CA 95211, USA zstahlschmidt@pacific.edu.
Zachary R
ZR
Stahlschmidt
D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D017812:Colubridae / Q000276:immunology / Q000502:physiology*; D004063:Digestion; D015536:Down-Regulation; D004435:Eating; D004734:Energy Metabolism; D005260:Female; D007113:Immunity, Innate; D008297:Male; D064307:Microbiota; D015854:Up-Regulation
Cornsnake; Hemoagglutination; Hemolysis; Immune function; Specific dynamic action; Tradeoff