NO RELATIONSHIP OBSERVED BETWEEN HABITAT TYPE AND RICKETTSIA PRESENCE IN ECTOPARASITES COLLECTED FROM RODENTS IN SOUTHWESTERN TENNESSEE

摘要

Ectoparasites such as fleas and ticks are important vectors of pathogens affecting humans, domesticated animals, and wildlife. Habitat type is a major determinant of abundance of small mammals, abundance of associated ectoparasites, and community composition, but the role habitats have in the association of a pathogen occurring within an ectoparasite is currently unknown. We tested the hypothesis that natural history and habitat type of small mammal hosts shape the probability of their ectoparasites serving as hosts for a pathogen. Ectoparasites were collected from small mammals captured in mature hardwood forests, midrotation, previously thinned loblolly pine plantations, and early successional field habitats. The ectoparasites were screened for Rickettsia using genus-specific polymerase chain reaction. Rodents consisted of 14 Peromyscus leucopus with 28.57 Rickettsia-infected ectoparasites, 25 Sigmodon hispidus with 8.86 infected ectoparasites, and 2 Microtus pinetorum with 0.00 infected ectoparasites. Rickettsia was identified in 13 (12.38) of the 105 ectoparasites screened from 41 (17.01) of the 241 small mammal hosts. No significant association between host traits, habitat type, and Rickettsia-positive ectoparasites was detected. Although habitat type and availability of small mammals may shape the abundance and composition of ectoparasite communities, results of our study suggested these determinants likely do not influence the probability of Rickettsia infection.