Use of a polymerase chain reaction assay to detect bovine herpesvirus type 2 DNA in skin lesions from cattle suspected to have pseudo-lumpy skin disease

Beef cattle from a herd in north Alabama were examined because of an outbreak of nonfatal skin disease characterized by discrete circumscribed areas of inflammation that developed on the skin from the neck to the hips. Areas of inflammation, which tended to be superficial, underwent necrosis and scabbed over. The scabs eventually dropped off leaving discrete, round, whitish, hairless lesions that were 1.2 to 2.5 cm diameter. Because clinical signs were consistent with those expected with pseudo-lumpy skin disease (PLSD) caused by bovine herpesvirus type 2 (BHV-2), samples from 16 representative animals were submitted for BHV-2 testing. All 16 animals were seropositive for BHV-2, but the virus could not be isolated from skin biopsy specimens or buffy coat samples. Results of a polymerase chain reaction assay incorporating primers designed to amplify 2 DNA sequences from BHV-2 were positive for 3 of the 10 cattle, suggesting that skin lesions in these cattle were a result of PLSD. Our findings suggest that PLSD may be more common and widespread in the United States than suggested by the frequency with which BHV-2 has been isolated from cattle with PLSD-like skin lesions.

Seroprevalence of Borrelia burgdorferi in dogs in Alabama, USA

A random sample of private small-animal practices in Alabama submitted sera from dogs with known tick contact. A total of 579 samples from the three geographic regions of the state were collected (58% of the targeted sample size). Sera were screened for antibodies to Borrelia burgdorferi using an indirect fluorescent antibody (IFA) test which had a sensitivity and specificity of greater than 90%. Anti-B burgdorferi titers of > or = 1:64 were considered to be positive, based on results from B. burgdorferi-inoculated dogs. Ten of the 579 samples (1.7%) were positive, and titers ranged from 1:64 to 1:512. Seropositive dogs were found throughbout the state, and there was no significant difference in seroprevalence by region (Mantel-Haenszel chi 2, P = 0.85). These results indicate that the seroprevalence for canine Lyme disease in Alabama is low and that use of the canine Lyme disease vaccine is not justified.

Severe idiopathic thymic hemorrhage in two littermate dogs

Two 6-month-old littermate Shetland Sheepdogs were found to have severe thymic hemorrhage unassociated with trauma or poisoning. One dog survived the insult with supportive care, and the other died and was necropsied. Antemortem laboratory data and radiographic findings for both dogs were consistent with acute blood loss into the mediastinum. Hemorrhage was restricted to the thymus and mediastinum in both dogs.

Interpreting the pathologist's report

It is imperative that the clinician/practitioner and diagnostic pathologist communicate. Both individuals practice their profession with innate professional biases based on training and experience. Like clinical medicine, pathology is a professional art and is subject to interpretative variance. When the clinician receives a pathological report that does not agree with the clinical presentation, there is an obligation to communicate the concern to the pathologist and request a second opinion or agree on the need for submission of additional biopsy material.

Human effects of veterinary biological products

A 14-year-old male drank two glasses of milk from a gallon inoculated with 21 vials of live virus vaccine intended to immunize 1000 baby chicks against Newcastle Disease. The patient was managed with catharsis and careful observation, and remained completely asymptomatic in the following 28 days. Newcastle Disease virus (NDV) may cause paralytic neurotropic, viscerotropic, or pneumonotropic disease in chickens, but has limited effects on humans. Systemic exposure to this vaccine has not previously been reported in humans, although an aerosol NDV vaccine has caused self-limited conjunctivitis following ocular exposure. The human effects of veterinary biologicals remain poorly defined. The limited literature existing in regards to the human experience with common veterinary vaccines is reviewed.