Featured Publications:
Kuster CE, Singer RS, Althouse GC Theriogenology 61:691-703 Morphologic assessment of spermatozoa is an integral component in the analysis of semen. Whether a technician rapidly screening semen quality at a commercial stud, a veterinarian performing breeding soundness examinations, a clinician at a reference andrology laboratory providing auditing or diagnostic services, or a researcher evaluating morphology…
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Singer RS, et al The Lancet: Infectious Diseases 3:47-51 Antibiotic-resistant bacteria were first identified in the 1940s, but while new antibiotics were being discovered at a steady rate, the consequences of this phenomenon were slow to be appreciated. Today, the excessive use of antibiotics compounded by the paucity of new agents on the market has…
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Hoar BR, Carpenter TE, Singer RS, Gardner IA American Journal of Veterinary Research 64:520-529 OBJECTIVE: To create a stochastic model to quantify the risk that shipments of cattle from regions within the United States would contain animals seropositive for bluetongue virus and to determine shipment-level accuracy of serologic testing by use of a competitive ELISA…
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Cooke CL, Singer RS, Jang SS, Hirsh DC Journal of the American Veterinary Medical Association 220:190-192 OBJECTIVE: To assess the strain heterogeneity of enrofloxacin-resistant Escherichia coli associated with urinary tract infections in dogs at a veterinary medical teaching hospital (VMTH). In addition, strains from other veterinary hospitals in California were compared with the VMTH strains…
Read MoreLipsitch M, Singer RS, Levin BR Proceedings of the National Academy of Sciences 99:5752-5754
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Jeffrey JS, Nolan LK, Tonooka KH, Wolfe S, Giddings CW, Horne SM, Foley SL, Lynne AM, Ebert JO, Elijah LM, Bjorklund G, Pfaff-McDonough SJ, Singer RS, Doetkott C Avian Diseases 46:48-52 This study was designed to compare virulence factors of cellulitis-derived Escherichia coli to colisepticemic E. coli in order to clarify whether E. coli associated…
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Singer RS, Atwill ER, Carpenter TE, Jeffrey JS, Johnson WO, Hirsh DC Epidemiology and Infection 126:139-145 In epidemiological studies of infectious disease, researchers often rely on specific cues of the host, such as clinical signs, as surrogate indicators of pathogen presence. A selection bias would manifest if the specific visual cues used in sampling for…
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Singer RS, MacLachlan NJ, Carpenter TE Journal of Veterinary Diagnostic Investigation 13:43-49 Central to the development of rational trade policies pertaining to bluetongue virus (BTV) infection is determination of the risk posed by ruminants previously exposed to the virus. Precise determination of the maximal duration of infectious viremia is essential to the development of an…
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Singer RS, Jeffrey JS, Carpenter TE, Cooke CL, Atwill ER, Johnson WO, Hirsh DC Veterinary Microbiology 75:59-71 Avian cellulitis in broiler chickens is primarily caused by Escherichia coli. Previous research found that the E. coli isolates of cellulitis origin were unique to each ranch, suggesting that these E. coli were endemic within the ranch environment.…
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Singer RS, Johnson WO, Jeffrey JS, Chin RP, Carpenter TE, Atwill ER, Hirsh DC Journal of Veterinary Diagnostic Investigation 12:118-126 A general problem for microbiologists is determining the number of phenotypically similar colonies growing on an agar plate that must be analyzed in order to be confident of identifying all of the different strains present…
Read MoreSwift PK, Wehausen JD, Ernest HB, Singer RS, Pauli AM, Kinde H, Rocke TE, Bleich VC Journal of Wildlife Diseases 36:184-189 During a routine telemetry flight of the Mojave Desert (California, USA) in August 1995, mortality signals were detected from two of 12 radio-collared female desert bighorn sheep (Ovis canadensis) in the vicinity of Old…
Read MoreJeffrey JS, Chin RP, Singer RS Avian Diseases 43:491-496 The purpose of this study was to identify Escherichia coli isolates that could be characterized as cellulitis pathogens. Twelve E. coli isolates from diagnostic cases of cellulitis or mixed infections with various serotypes were compared for ability to produce cellulitis and internal lesions indicative of systemic…
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Singer RS, Jeffrey JS, Carpenter TE, Cooke CL, Chin RP, Hirsh DC Avian Diseases 43:756-762 Avian cellulitis in broiler chickens is characterized by subcutaneous lesions that result in economic losses because of the partial or complete condemnation of the carcasses at processing. Escherichia coli is the primary causative agent of this condition. Previous research with…
Read MoreWoolums AR, Anderson ML, Gunther RA, Schelegele ES, LaRochelle DR, Singer RS, Boyle GA, Friebertshauser KE, Gershwin LJ American Journal of Veterinary Research 60:473-480 OBJECTIVE: To develop a model of bovine respiratory syncytial virus (BRSV) infection that induces severe disease similar to that seen in some cattle with naturally acquired BRSV infection. ANIMALS: 25 male…
Read MoreWoolums AR, Singer RS, Boyle GA, Gershwin LJ Vaccine 17:1293-1297 Formalin-inactivated respiratory syncytial virus (FI-RSV) vaccination has been associated with severe disease in humans. Research in mice suggests that FI-RSV may prime for decreased interferon gamma (IFN-gamma) production at subsequent infection. Interferon-gamma production by peripheral blood mononuclear cells (PBMC) was measured following challenge of calves…
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