Systemic mycosis in three dogs from nonendemic regions.

Three dogs were examined for clinical signs ultimately attributed to systemic fungal infections. One dog was evaluated for chronic, ulcerated dermal lesions and lymphadenomegaly; one dog was examined for acute onset of unilateral blepharospasm; and one dog had diarrhea and hematochezia. Two of the dogs were diagnosed with blastomycosis (one with disseminated disease and the other with the disease localized to the left eye). The third dog was diagnosed with disseminated histoplasmosis. None of the dogs originated from, or had traveled to, typical regions endemic for these fungal diseases. All diagnoses were established from histopathology and either polymerase chain reaction (PCR) or cytology and culture. The two dogs diagnosed with blastomycosis were treated with either itraconazole or ketoconazole with apparent resolution of the infections. The dog with ocular involvement had an enucleation prior to beginning therapy. The dog diagnosed with histoplasmosis was euthanized without treatment. In patients with characteristic clinical features, systemic fungal infections should still be considered as differential diagnoses regardless of their travel history.

Development of a bead-based multiplex PCR assay for the simultaneous detection of multiple Mycoplasma species.

We describe the development and analytical validation of a 7-plex polymerase chain reaction assay coupled to a bead-based liquid suspension array for detection of multiple ruminant Mycoplasma spp. The assay employs a combination of newly designed and previously validated primer-probe sets that target genetic loci specific for Mycoplasma bovis, Mycoplasma mycoides cluster, Mycoplasma mycoides subsp. mycoides SC (MmmSC) and Mycoplasma capricolum subspecies capripneumoniae (Mccp). Analytical sensitivity for the targeted Mycoplasma species ranged from 10 fg to 1 pg of purified gDNA extracted from broth cultures (approximately 8-800 MmmSC genome equivalents). In silico comparison of primers and probes, and analytical assessment with a range of near-neighbor Mycoplasma species and multiple bacterial respiratory pathogens demonstrated 100% analytical specificity of the assay. To assess assay performance and diagnostic specificity, 192 bovine respiratory samples were analyzed by incorporating a high throughput DNA extraction platform. The assay correctly classified all samples as negative for MmmSC or Mccp. All 33 field samples confirmed as positive for M. bovis by sequencing the uvrC gene were positive in the assay. The results from this study indicate that the bead-based liquid suspension array will provide a reliable, analytically sensitive and specific platform to simultaneously interrogate ruminant respiratory samples for multiple Mycoplasma species, including M. mycoides cluster organisms that are exotic to the United States. Sequential addition of primer-probe sets to the assay did not significantly impact analytical sensitivity of individual primer-probe combinations, suggesting that expanding the assay to include more Mycoplasma species will not compromise overall performance.

Imaging diagnosis-metastatic adrenal pheochromocytoma in a dog.

A 10-year-old Akita mix became acutely paraplegic. Upon magnetic resonance imaging, multiple, slightly T2-hyperintense, T1-isointense extradural masses, relative to spinal cord were found in the vertebral canal. The retroperitoneal masses had mixed T2-signal intensity. The contrast enhancement pattern for the spinal masses was both homogenous and heterogenous. The diagnosis was metastatic pheochromocytoma. Signal intensity of the tumors in this dog was similar to reports of pheochromocytoma in human beings.

Disseminated Bovine viral diarrhea virus in a persistently infected alpaca (Vicugna pacos) cria.

Bovine viral diarrhea virus (BVDV) is an emerging infectious pathogen of concern to the alpaca industry. A 4-month-old, intact, male alpaca cria was diagnosed as persistently infected with BVDV on the basis of repeated positive antemortem polymerase chain reaction (PCR) and virus isolation (VI) assays and negative serologic titers to BVDV. Immunohistochemistry, real-time reverse transcription PCR, and VI performed on tissues collected at necropsy demonstrated disseminated BVDV-1b infection. Virus was detected in multiple tissues, including parotid salivary gland, testes, prostate, kidneys, skin, and gastrointestinal tract. Demonstration of BVDV in previously unreported tissues suggests additional potential routes of BVDV transmission in alpacas.

Quantification, distribution, and possible source of bacterial biofilm in mouse automated watering systems.

The use of automated watering systems for providing drinking water to rodents has become commonplace in the research setting. Little is known regarding bacterial biofilm growth within the water piping attached to the racks (manifolds). The purposes of this project were to determine whether the mouse oral flora contributed to the aerobic bacterial component of the rack biofilm, quantify bacterial growth in rack manifolds over 6 mo, assess our rack sanitation practices, and quantify bacterial biofilm development within sections of the manifold. By using standard methods of bacterial identification, the aerobic oral flora of 8 strains and stocks of mice were determined on their arrival at our animal facility. Ten rack manifolds were sampled before, during, and after sanitation and monthly for 6 mo. Manifolds were evaluated for aerobic bacterial growth by culture on R2A and trypticase soy agar, in addition to bacterial ATP quantification by bioluminescence. In addition, 6 racks were sampled at 32 accessible sites for evaluation of biofilm distribution within the watering manifold. The identified aerobic bacteria in the oral flora were inconsistent with the bacteria from the manifold, suggesting that the mice do not contribute to the biofilm bacteria. Bacterial growth in manifolds increased while they were in service, with exponential growth of the biofilm from months 3 to 6 and a significant decrease after sanitization. Bacterial biofilm distribution was not significantly different across location quartiles of the rack manifold, but bacterial levels differed between the shelf pipe and connecting elbow pipes.