Ovine pulmonary adenocarcinoma (OPA) is a transmissible lung cancer caused by Jaggsiekte sheep retrovirus (JSRV). It is difficult to identify animals infected with JSRV but are clinically healthy. The virus does not induce a specific antibody response and, although proviral DNA sequences of JSRV can be found in mononuclear blood cells, the detection is inconsistent. The aim of this study was to investigate the presence of JSRV in the bone marrow of infected sheep and develop a more consistent screening method. Immunohistochemical examination of bone marrow samples from 8 asymptomatic JSRV-infected sheep revealed the presence of positively labelled cells. However, JSRV could not be detected by a highly sensitive polymerase chain reaction (PCR) in bone marrow aspirates periodically collected from these animals. Results suggest that JSRV-infected cells may be present in the bone marrow of symptomless animals, but the number is below the detectable level for PCR. Therefore, this technique does not seem to be helpful for preclinical diagnosis of OPA.

An antimicrobial susceptibility test was conducted to compare the resistance rates among Campylobacter spp. isolates from dogs (n = 50) raised under diverse conditions and humans (n = 50). More than 60% of Campylobacter (C.) jejuni from dogs and humans showed resistance to nalidixic acid, enrofloxacin and ciprofloxacin. C. jejuni isolates from humans showed higher resistance to tetracycline (83.3%) and ampicillin (91.3%) than those from dogs. None of the C. jejuni or Campylobacter coli isolates from humans or dogs were resistant to erythromycin. Overall, 85% of Campylobacter spp. isolates showed a multidrug resistant phenotype. Nucleotide sequencing analysis of the gryA gene showed that 100% of NA. /CIP. olates from dogs and humans had the Thr-86. h-Ile mutation, which is associated with fluoroquinolone resistance. flaA PCR restriction fragment length polymorphism (RFLP) typing to differentiate the isolates below the species level revealed 12 different clusters out of 73 strains. The human isolates belonged to eight different RFLP clusters, while five clusters contained dog and human isolates.

Objective-To evaluate the effects of various concentrations of l-lysine on in vitro replication of feline herpesvirus 1 (FHV-1). Sample- Cultures of Crandell-Rees feline kidney (CRFK) cells. Procedures- CRFK cells were inoculated with FHV-1 and maintained in media with 20 combinations of l-arginine and l-lysine concentrations. Changes in cell viability were monitored by continuous measurement of electrical impedance of cultured cells and by observation of viral cytopathic effects. Viral load was determined by use of quantitative PCR assay in supernatants obtained from infected cultures at specified time points. Results- Increases in l-lysine concentration had no effect on the kinetics of cell death in FHV-1-infected cultures. There was also no significant effect (r2 < 0.1) on viral DNA load for l-arginine concentrations ≥ 12 μg/mL There was a significant effect of increases in l-lysine concentration on viral DNA load in media supplemented with 6 μg of l-arginine/mL (mean ± SD slope, −4,641 ± 1,626 units; adjusted r2 = 0.45). However, the difference between the lowest (1 × 10(6.28) copies/μL) and highest (1 × 10(6.86) copies/μL) FHV-1 DNA load in these media was < 1 logarithm. Conclusions and Clinical Relevance-The difference in FHV-1 DNA load was unlikely to be biologically important. Various l-lysine concentrations did not inhibit in vitro replication of FHV-1 at l-arginine concentrations sufficient to maintain cell growth. This conclusion was consistent with results of other studies in which investigators have not detected a consistently beneficial effect when l-lysine is administered to FHV-1-infected cats.

The objective of this pilot study was to determine the efficacy of inactivated (1 or 2 dose) and live-attenuated chimeric porcine circovirus (PCV)1-2 vaccines in sows using the PCV2-spiked semen model. Thirty-five sows were randomly divided into 6 groups: negative and positive controls, 1 dose inactivated PCV1-2 vaccine challenged (1-VAC-PCV2), 2 dose inactivated PCV1-2 vaccine challenged (2-VAC-PCV2), 1 dose live-attenuated PCV1-2 vaccine unchallenged (1-LIVE-VAC), and 1 dose live-attenuated PCV1-2 vaccine challenged (1-LIVE-VAC-PCV2). The inactivated PCV1-2 vaccine induced higher levels of PCV2-specific antibodies in dams. All vaccination strategies provided good protection against PCV2 viremia in dams, whereas the majority of the unvaccinated sows were viremic. Four of the 35 dams became pregnant: a negative control, a positive control, a 2-VAC-PCV2 sow, and a 1-LIVE-VAC-PCV2 sow. The PCV2 DNA was detected in 100%, 67%, and 29% of the fetuses obtained from the positive control, inactivated vaccinated, or live-attenuated vaccinated dams, respectively. The PCV2 antigen in hearts was only detectable in the positive control litter (23% of the fetuses). The PCV1-2 DNA was detected in 29% of the fetuses in the litter from the 1-LIVE-VAC-PCV2 dam. Under the conditions of this pilot study, both vaccines protected against PCV2 viremia in breeding age animals; however, vertical transmission was not prevented.