Publications by authors named "Stephen Sells"

Forty-one isolates of Bisgaard taxon 6 obtained from guinea pigs, pandas, pigs and muskrat and isolates of taxon 10 from horses and horse bites in humans were subjected phenotypic characterization. Production of acid from (-)-d-mannitol, (-)-d-sorbitol and (+)-d-glycogen separated taxon 10 (positive) from taxon 6 (negative), while from two to 11 phenotypic characteristics separated taxa 6 and 10 from the 32 genera of reported so far. Forty-four strains were genetically characterized.

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This study was undertaken to investigate the bacterial and fungal microflora on the external genitalia of a population of healthy male donkeys in the state of Michigan, USA. The aim was to identify and determine the frequency of occurrence of these microorganisms using seven different isolation media and standard microbiological procedures. The sites (urethral fossa [fossa glandis], dorsal diverticulum of the urethral sinus, distal urethra, and penile surface) in the distal reproductive tract were cultured and each isolated microorganism identified.

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A 7-year-old pregnant Angus cow was found dead in the field. At necropsy, the aortic valve was expanded by moderate fibrous connective tissue and acidophilic coagulum containing multifocal marked bacteria, mineral, neutrophils, and red blood cells. Numerous tiny grayish, opaque bacterial colonies were detected on blood agar plates at 7 days after inoculation with a swab of the heart valve of the cow.

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Nocardioform actinomycetes are significant causes of placentitis and abortions in horses. In the current study, antimicrobial susceptibility patterns of 38 Amycolatopsis spp. and 22 Crossiella equi isolates, the most common nocardioform actinomycetes causing placentitis in horses, were evaluated.

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This study was undertaken to investigate the prevalence of Taylorella asinigenitalis in a subset of the donkey population of Michigan and in other equids on farms on which the organism was identified. Other aims were to further characterize the carrier state in terms of persistence and preferred sites of colonization of T. asinigenitalis in the male donkey as well as determine the genotype of any isolates of the organism.

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A 25-year-old pregnant American Quarter Horse mare presented with a 1-week history of progressively worsening vaginal discharge. Transrectal ultrasound revealed increased thickness of the combined uterus and placenta with evidence of chorioallantoic edema but no placental separation. A thickened amnion was visible on transabdominal ultrasound.

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A single-nucleotide polymorphism (A(2254) or G(2254)) in open reading frame 30 (ORF30) has been linked to the neuropathogenic phenotype of equine herpesvirus-1 (EHV-1). Identification of this polymorphism led to the development of a real-time PCR (rPCR) assay using allelic discrimination (E(2)) to distinguish between potentially neuropathogenic and nonneuropathogenic EHV-1 strains (G. P.

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Nocardioform placentitis associated with gram positive branching actinomycetes caused a record number of abortions in mares diagnosed by the University of Kentucky Veterinary Diagnostic Laboratory (UKVDL) affecting the 2011 foal crop (2011 foal crop: the cohort of foals conceived during the 2010 breeding season). The goal of the present study is to make a comprehensive analysis of this outbreak in terms of frequencies of the bacteria causing nocardioform placentitis mediated abortions and to investigate the ages of fetuses, abortion months and breeding times. In the present study, characteristic slow-growing, pungent/soil odor gram positive branching actinomycetes were recovered in high numbers in placental specimens in 76 abortion cases diagnosed as nocardioform placentitis by pathologists.

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This study showed that under specifically defined conditions with respect to nucleic acid extraction method and testing reagents, a previously described real-time reverse transcription-PCR (rRT-PCR) assay (T1 assay) provides sensitivity equal to or higher than that of virus isolation for the detection of equine arteritis virus in semen.

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The objective of the current study was to determine the capability of 3 recently described one-step TaqMan real-time reverse transcription polymerase chain reaction (real-time RT-PCR) assays targeting the nucleoprotein (NP), matrix (M), and hemagglutinin (HA) genes of H3N8 Equine influenza virus (EIV NP, EIV M, and EIV HA3 assays, respectively) to detect Canine influenza virus (CIV). The assays were initially evaluated with nucleic acid extracted from tissue culture fluid (TCF) containing the A/canine/FL/43/04 strain of Influenza A virus associated with the 2004 canine influenza outbreak in Florida. The EIV NP, EIV M, and EIV HA3 assays could detect CIV nucleic acid at threshold cycle (Ct) values of 16.

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The objective of this study was to develop and evaluate new TaqMan real-time reverse transcription-PCR (rRT-PCR) assays by the use of the minor groove binding probe to detect a wide range of equine influenza virus (EIV) strains comprising both subtypes of the virus (H3N8 and H7N7). A total of eight rRT-PCR assays were developed, targeting the nucleoprotein (NP), matrix (M), and hemagglutinin (HA) genes of the two EIV subtypes. None of the eight assays cross-reacted with any of the other known equine respiratory viruses.

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Objective: To identify Actinobacillus spp isolates recovered from fetuses and pericardial fluid from horses affected with mare reproductive loss syndrome (MRLS) and determine whether these bacterial species are the same as those isolated from clinically normal horses.

Sample Population: Isolates of actinobacilli recovered from 18 horses with pericarditis and 109 fetuses aborted by mares affected by MRLS. Procedures-Actinobacillus spp isolates were identified to the level of species or subspecies by use of conventional phenotypic tests and biochemical and enzyme test kits.

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Case Description: A 4-year-old Thoroughbred mare was evaluated because of placental abnormalities and a retained placental remnant.

Clinical Findings: Microbial culture of the placenta yielded pure growth of Amycolatopsis spp. Histologic examination of the placenta revealed a focally expanding chorionitis with intralesional gram-positive filamentous bacilli and multifocal allantoic adenomatous hyperplasia on the apposing allantoic surface.

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