Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Hosts use altered macronutrient intake to circumvent parasite-induced reduction in fecundity
AU - Ponton, Fleur
AU - Lalubin, Fabrice
AU - Fromont, Caroline
AU - Wilson, Kenneth
AU - Behm, Carolyn
AU - Simpson, Stephen J.
PY - 2011/1
Y1 - 2011/1
N2 - Explanations for the evolution of pathogen-induced fecundity reduction usually rely on a common principle: the trade-off between host longevity and reproduction. Recent advances in nutritional research have, however, challenged this assumption and shown that longevity and reproduction are not inextricably linked. In this study, we showed that beetles infected by cysticercoids of the tapeworm Hymenolepis diminuta increased their total food intake and, more particularly, their carbohydrate consumption compared with uninfected insects. This increased intake was only pronounced during the first 12 days p.i., when the parasite grows and develops into a mature metacestode. Despite consuming more nutrients, infected individuals sustained lower levels of body lipid and were less efficient at converting ingested protein to body protein. However they demonstrated a capacity to compose a diet that sustained high levels of reproductive output unless confined to foods that were nutritionally dilute. We did not find any indication that macronutrient intakes had an effect on host pro-phenoloxidase activity; however, phenoloxidase activity was significantly affected by protein intake. Our results showed that when offered nutritionally complementary diets, infected hosts do not systematically suffer a reduction in fecundity. Thus, in our view, the assumption that a reduction in host reproduction represents an adaptive response by the host or the parasite to divert resources away from reproduction toward other traits should be reassessed.
AB - Explanations for the evolution of pathogen-induced fecundity reduction usually rely on a common principle: the trade-off between host longevity and reproduction. Recent advances in nutritional research have, however, challenged this assumption and shown that longevity and reproduction are not inextricably linked. In this study, we showed that beetles infected by cysticercoids of the tapeworm Hymenolepis diminuta increased their total food intake and, more particularly, their carbohydrate consumption compared with uninfected insects. This increased intake was only pronounced during the first 12 days p.i., when the parasite grows and develops into a mature metacestode. Despite consuming more nutrients, infected individuals sustained lower levels of body lipid and were less efficient at converting ingested protein to body protein. However they demonstrated a capacity to compose a diet that sustained high levels of reproductive output unless confined to foods that were nutritionally dilute. We did not find any indication that macronutrient intakes had an effect on host pro-phenoloxidase activity; however, phenoloxidase activity was significantly affected by protein intake. Our results showed that when offered nutritionally complementary diets, infected hosts do not systematically suffer a reduction in fecundity. Thus, in our view, the assumption that a reduction in host reproduction represents an adaptive response by the host or the parasite to divert resources away from reproduction toward other traits should be reassessed.
KW - Geometric Framework
KW - Nutritional ecology
KW - parasite
KW - Macronutrient
U2 - 10.1016/j.ijpara.2010.06.007
DO - 10.1016/j.ijpara.2010.06.007
M3 - Journal article
VL - 41
SP - 43
EP - 50
JO - International Journal for Parasitology
JF - International Journal for Parasitology
SN - 0020-7519
IS - 1
ER -