title: Evaluation of diagnostic methods for Myocoptes musculinus according to age and treatment status of mice (Mus musculus).
abstract: Detecting and controlling murine fur mites continues to be challenging. Here we compared the efficacy of fur-pluck, cage PCR, and fur PCR testing of mice naturally infested with Myocoptes musculinus and make recommendations regarding the application of these diagnostic strategies in aged or treated mice. We compared all 3 diagnostic methods in groups of infested and noninfested control mice over time. For fur plucks, we used a scoring system to quantitatively compare mite infestations across ages. Mice that were 4 wk old had higher egg and mite scores than did older mice, with average scores at 4 wk corresponding to 40 to 100 individual fur mites and eggs per sample. Furthermore, 15% and 20% of samples from infested mice at 24 and 28 wk of age, respectively, lacked all fur mites and eggs. Cage PCR results varied as mice grew older. Fur PCR testing was the most sensitive and specific assay in untreated infested mice, particularly when mite densities were low. In addition, we compared fur-pluck and fur PCR tests for evaluating the efficacy of selamectin treatment. Two treatments with selamectin eliminated Myocoptes fur-mite infestations. At 8 wk after treatment, all fur-pluck samples were negative, but one-third of treated infested cages remained positive by fur PCR assay; at 16 wk after treatment, all cages were negative by fur PCR assay. Because offspring of infested mice were invariably heavily infested, breeding of suspected infested mice with subsequent testing of offspring was the definitive testing strategy when fur-pluck and PCR results conflicted.
authors.affiliation: Department of Molecular and Comparative Pathobiology, Johns Hopkins School of Medicine, Baltimore, Maryland, USA; Division of Veterinary Resources, National Institutes of Health, Poolesville, Maryland, USA. kelly.rice@nih.gov.
authors.forename: Kelly A
authors.initials: KA
authors.lastname: Rice
authors.affiliation: Research Animal Resources, Johns Hopkins School of Medicine, Baltimore, Maryland, USA.
authors.forename: Lauren K
authors.initials: LK
authors.lastname: Albacarys
authors.affiliation: Department of Molecular and Comparative Pathobiology, Johns Hopkins School of Medicine, Baltimore, Maryland, USA.
authors.forename: Kelly A
authors.initials: KA
authors.lastname: Metcalf Pate
authors.affiliation: Research Animal Diagnostic Services, Charles River, Wilmington, Massachusetts, USA.
authors.forename: Cheryl
authors.initials: C
authors.lastname: Perkins
authors.affiliation: Research Animal Diagnostic Services, Charles River, Wilmington, Massachusetts, USA.
authors.forename: Kenneth S
authors.initials: KS
authors.lastname: Henderson
authors.affiliation: Department of Molecular and Comparative Pathobiology, Johns Hopkins School of Medicine, Baltimore, Maryland, USA.
authors.forename: Julie
authors.initials: J
authors.lastname: Watson
mesh_terms: D000818:Animals; D000977:Antiparasitic Agents / Q000627:therapeutic use; D005260:Female; D007559:Ivermectin / Q000031:analogs & derivatives / Q000627:therapeutic use; D008297:Male; D051379:Mice; D008924:Mite Infestations / Q000175:diagnosis / Q000662:veterinary*; D008925:Mites; D016133:Polymerase Chain Reaction; D012376:Rodent Diseases / Q000175:diagnosis*; D012680:Sensitivity and Specificity
chemical_list: D000977:Antiparasitic Agents; D007559:Ivermectin; C414354:selamectin