title: Effects of parasitism on host reproductive investment in a rodent-flea system: host litter size matters.
abstract: Parents may alter offspring phenotype depending on the type of environment they encounter. Parasitism is a common stressor; therefore, maternal reproductive investment could change in response to parasitic infection. However, few experiments have investigated the relationship between parasitism and maternal investment, whereas earlier field studies provided contradictory evidence. We investigated number, sex ratio, and growth of offspring in two rodent species, solitary altricial Meriones crassus and social precocial Acomys cahirinus, exposed to parasitism by fleas Xenopsylla ramesis and Parapulex chephrenis. No effect of treatment on litter size or sex ratio of a litter was found in either rodent species. Flea parasitism was found to affect pre-weaning body mass gain in M. crassus, but not in A. cahirinus pups. Furthermore, it appeared that female M. crassus invested resources into their offspring differently in dependence of litter size. In small litters (1-3 offspring), pups from infested females gained more body mass before weaning than pups from uninfested mothers. However, this trend was reversed in females with large litters indicating that parasitized females have a finite amount of resources with which to provision their young. Thus, M. crassus mothers parasitized by fleas seemed to receive some sort of external cues (e.g., stress caused by infestation) that prompted them to alter offspring provisioning, depending on species-specific possibilities and constraints. Therefore, parasites could be a mediator of environmentally induced maternal effects and offspring provisioning may have adaptive value against parasitism.
authors.affiliation: Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 8499000, Midreshet Ben-Gurion, Israel. warburte@post.bgu.ac.il.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Warburton
authors.affiliation: Wyler Department of Dryland Agriculture, French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 8499000, Midreshet Ben-Guriron, Israel.
authors.forename: Irina S
authors.initials: IS
authors.lastname: Khokhlova
authors.affiliation: Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 8499000, Midreshet Ben-Gurion, Israel.|Department of Plant Sciences, University of Tennessee, Knoxville, TN, 37996, USA.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Dlugosz
authors.affiliation: Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 8499000, Midreshet Ben-Gurion, Israel.|Wyler Department of Dryland Agriculture, French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 8499000, Midreshet Ben-Guriron, Israel.
authors.forename: Luther Van
authors.initials: LV
authors.lastname: Der Mescht
authors.affiliation: Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 8499000, Midreshet Ben-Gurion, Israel.
authors.forename: Boris R
authors.initials: BR
authors.lastname: Krasnov
mesh_terms: D000818:Animals; D004777:Environment; D005260:Female; D058267:Flea Infestations / Q000469:parasitology; D005849:Gerbillinae / Q000469:parasitology*; D006790:Host-Parasite Interactions; D008098:Litter Size; D008297:Male; D051189:Murinae / Q000469:parasitology*; D012098:Reproduction / Q000502:physiology*; D005423:Siphonaptera / Q000502:physiology*; D013045:Species Specificity; D013559:Symbiosis; D058260:Xenopsylla / Q000502:physiology*
keywords: Acomys cahirinus; Fleas; Meriones crassus; Offspring growth; Parapulex chephrenis; Parental effects; Rodents; Xenopsylla ramesis