Detection of Ovis aries papillomavirus type 2 DNA sequences in a sarcoid-like mass in the mouth of a pig.

An oral mass was surgically excised from the gingiva of a pig. As the mass had a similar histological appearance to an equine sarcoid, DNA was extracted and consensus PCR primers used to amplify papillomavirus (PV) DNA. DNA sequences from Ovis aries papillomavirus (OaPV) type 2 were amplified both from a section of the entire mass as well as an area deeper within the mass away from the surface of the lesion. No other PV types were detected within the oral lesion. Ovis aries PV2 is a Delta PV that is closely related to the bovine Delta PVs that cause sarcoids in horses and cats. These results suggest that OaPV2 may be able to infect pigs and this virus could have caused the mesenchymal neoplasm in the mouth of this pig. This is the first evidence that a non-bovine PV can infect a non-host species and the first report of a sarcoid-like mass in pigs. These observations add to the range of species in which PV-associated neoplasia has been reported and suggest that cross-species infection by other Delta PV types may be possible.

Feline Leukemia Virus (FeLV) Disease Outcomes in a Domestic Cat Breeding Colony: Relationship to Endogenous FeLV and Other Chronic Viral Infections.

Exogenous feline leukemia virus (FeLV) is a feline gammaretrovirus that results in a variety of disease outcomes. Endogenous FeLV (enFeLV) is a replication-defective provirus found in species belonging to the Felis genus, which includes the domestic cat (Felis catus). There have been few studies examining interaction between enFeLV genotype and FeLV progression. We examined point-in-time enFeLV and FeLV viral loads, as well as occurrence of FeLV/enFeLV recombinants (FeLV-B), to determine factors relating to clinical disease in a closed breeding colony of cats during a natural infection of FeLV. Coinfections with feline foamy virus (FFV), feline gammaherpesvirus 1 (FcaGHV-1), and feline coronavirus (FCoV) were also documented and analyzed for impact on cat health and FeLV disease. Correlation analysis and structural equation modeling techniques were used to measure interactions among disease parameters. Progressive FeLV disease and FeLV-B presence were associated with higher FeLV proviral and plasma viral loads. Female cats were more likely to have progressive disease and FeLV-B. Conversely, enFeLV copy number was higher in male cats and negatively associated with progressive FeLV disease. Males were more likely to have abortive FeLV disease. FFV proviral load was found to correlate positively with higher FeLV proviral and plasma viral load, detection of FeLV-B, and FCoV status. Male cats were much more likely to be infected with FcaGHV-1 than female cats. This analysis provides insights into the interplay between endogenous and exogenous FeLV during naturally occurring disease and reveals striking variation in the infection patterns among four chronic viral infections of domestic cats.IMPORTANCE Endogenous retroviruses are harbored by many animals, and their interactions with exogenous retroviral infections have not been widely studied. Feline leukemia virus (FeLV) is a relevant model system to examine this question, as endogenous and exogenous forms of the virus exist. In this analysis of a large domestic cat breeding colony naturally infected with FeLV, we documented that enFeLV copy number was higher in males and inversely related to FeLV viral load and associated with better FeLV disease outcomes. Females had lower enFeLV copy numbers and were more likely to have progressive FeLV disease and FeLV-B subtypes. FFV viral load was correlated with FeLV progression. FFV, FcaGHV-1, and FeLV displayed markedly different patterns of infection with respect to host demographics. This investigation revealed complex coinfection outcomes and viral ecology of chronic infections in a closed population.