Differences in the ectoparasite fauna between micromammals captured in natural and adjacent residential areas are better explained by sex and season than by type of habitat

Abstract

We compared the ectoparasite fauna in 608 micromammals (chiefly 472 wood mice Apodemus sylvaticus, 63 Algerian mice Mus spretus, and 51 greater white-toothed shrews Crocidura russula) captured in natural and adjacent residential areas in spring and autumn during three consecutive years in four areas in periurban Barcelona (NE Spain). We found little support for an association of urbanization with differences in infestation by ectoparasites. Prevalence of Rhipicephalus sp. tick in wood mice and shrews was significantly higher in residential than in natural habitats, and the opposite was found for the flea Ctenophtalmus andorrensis catalanensis in shrews. Marked differences in the prevalence of the flea Leptopsylla taschenbergi amitina in wood mice between seasons were observed in natural but not in residential habitats, probably due to enhanced flea survival probabilities in the latter. However, as a rule, males were more frequently and heavily infested than females, and the prevalence was higher in autumn than in spring. Our results suggest that the ectoparasite fauna of periurban micromammals is shaped more by other factors than by habitat modification. People living in residential areas are at risk of contact with the arthropods borne by non-commensal micromammals and the pathogens transmitted by them.

Drivers of Bartonella infection in micromammals and their fleas in a Mediterranean peri-urban area

“…Infestation by fleas, the most important vectors for Bartonella (Gutiérrez et al, 2015), was prevalent among the analyzed individuals, but we found little support for an effect of urbanization on prevalence of infestation by arthropods (Cevidanes et al, 2016). However, we found that one flea (Leptopsylla taschenbergi) showed marked differences in prevalence between seasons in natural areas, but prevalence was constant in residential areas, suggesting that narrower variations in environmental factors may had enhanced the survival probabilities in these habitats (Cevidanes et al, 2016). However, no such differences were found for other species of flea, which were more influenced of other factors such as season and host sex (Cevidanes et al, 2016).…”

“…However, we found that one flea (Leptopsylla taschenbergi) showed marked differences in prevalence between seasons in natural areas, but prevalence was constant in residential areas, suggesting that narrower variations in environmental factors may had enhanced the survival probabilities in these habitats (Cevidanes et al, 2016). However, no such differences were found for other species of flea, which were more influenced of other factors such as season and host sex (Cevidanes et al, 2016). In consequence, in the present study we aimed to get insight on the factors related to the prevalence of Bartonella in micromammals and their fleas in a Mediterranean peri-urban environment.…”

“…were included in this study. Detailed information on capture success for species and area can be found in (Cevidanes et al, 2016). Animals were transferred without handling to a plastic bag and weighed using a Pesola scale to the nearest 0.5 g and anaesthetized with a combination of ketamine (Domtor©, Esteve, Barcelona, Spain) and medetomidine (Imalgene©, Merial, Barcelona, Spain) (Chirife and Millán, 2014).…”

“…Once identified, fleas were grouped in 218 monospecific pools belonging to the following species: Ctenophtalmus andorrensis catalanensis (144 pools), Leptopsylla taschenbergi amitina (68 pools), Typhloceras poppei poppei (three pools), Nosopsyllus fasciatus (one pool) and Hystrichopsylla talpae (one pool). Detailed information about the prevalence and intensity of the retrieved fleas per species can be found in Cevidanes et al (2016). DNA was isolated from flea pools, host samples and fetuses from six pregnant Bartonella-positive wood mouse females using the High Pure PCR template preparation kit (Roche, Mannheim, Germany) according to the manufacturer's instructions with some modifications from Solano-Gallego et al (2012).…”

Risk factors of Leptospira infection in Mediterranean periurban micromammals

“…Higher Leptospira prevalence has been frequently associated with species occupying urban habitats (Andersen‐Ranberg et al., ), but this refers mostly to species such as Rattus spp., which are underrepresented in our wood mouse‐dominated sample (both in natural and residential areas). We also failed to detect differences between habitats in the ectoparasites infesting and Bartonella infecting these same micromammals (Cevidanes, Proboste, Chirife, & Millán, ; Cevidanes et al., ), suggesting that climatic conditions are relatively similar between residential and natural habitats. Mammal dispersal between natural and residential areas could also explain the lack of differences in Leptospira prevalence.…”