title: Age at weaning, immunocompetence and ectoparasite performance in a precocial desert rodent.
abstract: We studied the effects of early weaning on immunocompetence and parasite resistance in a precocial rodent Acomys cahirinus. We hypothesized that if parasite resistance is energetically expensive and nutritional and immunological support from mothers are necessary for the long-term health of offspring, then early weaned animals would be immunologically weaker and less able to defend themselves against parasites than later weaned animals. We weaned pups at 14, 21 or 28 days after birth and assessed their immunocompetence and resistance against fleas Parapulex chephrenis when they attained adulthood. Immunocompetence was assessed using leukocyte concentration (LC) and a phytohaemagglutinin injection assay (PHA test). To estimate resistance against fleas, we measured performance of fleas via the number of produced eggs and duration of development and resistance to starvation of the flea offspring. We found a significant positive effect of weaning age on the PHA response but not on LC. The effect of age at weaning on flea egg production was manifested in male but not female hosts, with egg production being higher if a host was weaned at 14 than at 28 days. Weaning age of the host did not affect either duration of development or resistance to starvation of fleas produced by mothers fed on these hosts. We conclude that even in relatively precocial mammals, weaning age is an important indicator of future immunological responses and the ability of an animal to resist parasite infestations. Hosts weaned at an earlier age make easier, less-resistant targets for parasite infestations than hosts weaned later in life.
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: Elizabeth M
authors.initials: EM
authors.lastname: Dlugosz
authors.affiliation: Institute of Vertebrate Biology, Research Facility Studenec, Academy of Sciences of the Czech Republic, Květná 8, 603 65 Brno, Czech Republic Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerpen, Belgium.
authors.forename: Joelle Goüy
authors.initials: JG
authors.lastname: de Bellocq
authors.affiliation: Desert Animal Adaptations and Husbandry, 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-Gurion, Israel.
authors.forename: Irina S
authors.initials: IS
authors.lastname: Khokhlova
authors.affiliation: Desert Animal Adaptations and Husbandry, 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-Gurion, Israel.
authors.forename: A Allan
authors.initials: AA
authors.lastname: Degen
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: Berry
authors.initials: B
authors.lastname: Pinshow
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 krasnov@bgu.ac.il.
authors.forename: Boris R
authors.initials: BR
authors.lastname: Krasnov
mesh_terms: D000818:Animals; D005260:Female; D058267:Flea Infestations / Q000276:immunology*; D006790:Host-Parasite Interactions / Q000276:immunology*; D007121:Immunocompetence / Q000502:physiology*; D007962:Leukocytes / Q000276:immunology; D008297:Male; D051189:Murinae / Q000254:growth & development* / Q000276:immunology* / Q000469:parasitology*; D010058:Oviposition / Q000502:physiology; D010835:Phytohemagglutinins / Q000276:immunology; D012737:Sex Factors; D005423:Siphonaptera / Q000502:physiology*; D013217:Starvation; D014886:Weaning
chemical_list: D010835:Phytohemagglutinins
keywords: Fleas; PHA response; Spiny mouse; Weaning