Male hosts are responsible for the transmission of a trophically transmitted parasite, Pterygodermatites peromysci, to the intermediate host in the absence of sex-biased infection

Center for Infectious Disease Dynamics, Department of Biology, 208 Mueller Laboratory, The Pennsylvania State University, University Park, PA 16802, USA.
International journal for parasitology (Impact Factor: 3.87). 05/2009; 39(11):1263-8. DOI: 10.1016/j.ijpara.2009.03.007
Source: PubMed


Field studies have identified that male-biased infection can lead to increased rates of transmission, so we examined the relative importance of host sex on the transmission of a trophically transmitted parasite (Pterygodermatites peromysci) where there is no sex-biased infection. We experimentally reduced infection levels in either male or female white-footed mice (Peromyscus leucopus) on independent trapping grids with an anthelmintic and recorded subsequent infection levels in the intermediate host, the camel cricket (Ceuthophilus pallidipes). We found that anthelmintic treatment significantly reduced the prevalence of infection among crickets in both treatment groups compared with the control, and at a rate proportional to the number of mice de-wormed, indicating prevalence was not affected by the sex of the shedding definitive host. In contrast, parasite abundance in crickets was higher on the grids where females were treated compared with the grids where males were treated. These findings indicate that male hosts contribute disproportionately more infective stages to the environment and may therefore be responsible for the majority of parasite transmission even when there is no discernable sex-biased infection. We also investigated whether variation in nematode length between male and female hosts could account for this male-biased infectivity, but found no evidence to support that hypothesis.


Available from: Lien Luong, Jun 30, 2014
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    • "In fact, reproductive performance of the same parasite species varies among host species (Schmid- Hempel and Schmid-Hempel, 1996; Riquelme et al. 2006; Ghimire and Phillips, 2010; Khokhlova et al. 2012), between host genders (Khokhlova et al. 2009a; Luong et al. 2009), among host age cohorts (Liberman et al. 2013; Veena and Manjunath, 2013), among hosts with different reproductive status (Dlugosz et al. 2014) and even among hosts of different nutritional status (Krasnov et al. 2005; Tschirren et al. 2007). This variation in parasite performance may be manifested not only in offspring quantity (Luong et al. 2009) but also in their quality (e.g. survival or body size; Campbell and Duffey, 1979; Liberman et al. 2013; Veena and Manjunath, 2013; Khokhlova et al. 2014). "
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    Parasitology 02/2014; 141(7):1-11. DOI:10.1017/S0031182014000109 · 2.56 Impact Factor
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    • "The parasite life cycle is completed when a mouse ingests a cricket with infectious cysts: the parasite larvae emerge from the cyst, enter the host intestinal lumen and develop into reproductive adults; the pre-patent period (from infection to production of eggs) is approximately 4–5 weeks (Oswald 1958b; Luong & Hudson 2012). Previous studies have shown that the infection biology in the intermediate host and parasite transmission in the definitive host are marked by strong temporal patterns, with peak levels of infection and egg shedding in early spring and late summer (Luong et al. 2009; Vandegrift & Hudson 2009). "
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    Molecular Ecology 10/2012; 22(1). DOI:10.1111/mec.12095 · 6.49 Impact Factor
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    • "Krasnov et al. (2005) investigated gender differ- ence401w 4 M [istincta Apodemus sylvaticus , in England (Behnke et al. 1999 ), many other studies failed to detect gender-biased parasitism by nematodes in other populations of this species (Fuentes et al. 2004 for Spain, Milazzo et al. 2010 for Italy). Moreover, no gender-biased parasitism was reported for rodents such as the yellow-necked fi eld mouse ( Apodemus fl avicollis ) (Ferrari et al. 2004 ), the white-footed mouse ( Peromyscus leucopus ) (Luong et al. 2009 ) and the bank vole ( Myodes glareolus ) (Ribas et al. 2009 ), while female-biased infestation by nematodes was detected in the Cape ground squirrel, Xerus inauris , in South Africa (Hillegass et al. 2008 ) and in two species of octodontids from Argentina (Rossin et al. 2010 ). "
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