Histopathology and risk factors associated with neotrombicula microti infestation in the endangered amargosa vole (Microtus Californicus scirpensis)

Caitlin N. Ott-Conn, Leslie Woods, Deana L. Clifford, Tammy Branston, Janet E Foley

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The Amargosa vole (Microtus californicus scirpensis) is a profoundly endangered rodent found only in the Central Mojave Desert, Inyo County, California, US. In 2010, severe cases of trombiculiasis, caused by larval Neotrombicula microti mites, were discovered among voles and sympatric small mammals. We evaluated Amargosa voles and sympatric rodents for infestation with N. microti December 2011–November 2012 and evaluated histopathology of ear tissue from 13 actively N. microti–infested Amargosa voles and 10 Amargosa voles with no gross evidence of current or past infestation. Rodents with current infestation had mites visible on tissue, typically ear pinnae, whereas mites were not seen on rodents with presumptive past infestation, but some of these animals had gross tissue scarring and loss consistent with healing from infestation. Ears from infested voles had severe granulocytic and necrotizing dermatitis, most associated with stylostome fragments, whereas few lesions were present in grossly uninfested voles. There was no association between body condition and infestation or severity of lesions. Significantly more voles were infested (37%) with N. microti than sympatric rodents (3%), suggesting that sympatric rodents do not serve as an important source of N. microti exposure to voles. Although this chigger infestation was common and induced severe localized pathology, we did not detect a fitness cost to infestation and recommend further evaluation of the disease to discern its significance in this conservation context.

Original languageEnglish (US)
Pages (from-to)680-687
Number of pages8
JournalJournal of Wildlife Diseases
Volume51
Issue number3
DOIs
StatePublished - Jul 10 2015

Fingerprint

Neotrombicula
histopathology
Microtus
risk factor
rodent
risk factors
rodents
mite
lesion
ears
lesions (animal)
mites
body condition
pathology
small mammal
chiggers
Mojave Desert
Microtus californicus
voles
mite infestations

Keywords

  • Amargosa vole
  • Auricular dermatitis
  • Chiggers
  • Microtus californicus scirpensis
  • Neotrombicula microti
  • Trombiculiasis

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology

Cite this

Histopathology and risk factors associated with neotrombicula microti infestation in the endangered amargosa vole (Microtus Californicus scirpensis). / Ott-Conn, Caitlin N.; Woods, Leslie; Clifford, Deana L.; Branston, Tammy; Foley, Janet E.

In: Journal of Wildlife Diseases, Vol. 51, No. 3, 10.07.2015, p. 680-687.

Research output: Contribution to journalArticle

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