Detection and Molecular Characterization of Two Gammaherpesviruses from Pantesco Breed Donkeys during an Outbreak of Mild Respiratory Disease

Viruses. 2021 Aug 2;13(8):1527. doi: 10.3390/v13081527.

Abstract

Equid and asinine gammaherpesviruses (GHVs; genus Percavirus) are members of the Herpesviridae family. Though GHVs have been reported in horse populations, less studies are available on gammaherpesviral infections in donkeys. This study reports the co-infection with two GHVs in Pantesco breed donkeys, an endangered Italian donkey breed. Samples (n = 124) were collected on a breeding farm in Southern Italy from 40 donkeys, some of which were healthy or presented erosive tongue lesions and/or mild respiratory signs. Samples were analysed by using a set of nested PCRs targeting the DNA polymerase, glycoprotein B, and DNA-packaging protein genes, and sequence and phylogenetic analyses were performed. Twenty-nine donkeys (72.5%) tested positive, and the presence of Equid gammaherpesvirus 7 and asinine herpesvirus 5 was evidenced. In 11 animals, we found evidence for co-infection with viruses from the two species. Virions with herpesvirus-like morphology were observed by electron microscopic examination, and viruses were successfully isolated in RK-13-KY cell monolayers. The histological evaluation of tongue lesions revealed moderate lympho-granulocytic infiltrates and rare eosinophilic inclusions. The detection of GHVs in this endangered asinine breed suggests the need long-life monitoring within conservation programs and reinforces the need for further investigations of GHV's pathogenetic role in asinine species.

Keywords: Equid gammaherpesvirus 7; Percavirus; asinine herpesvirus; asinine herpesvirus 5; donkey; gammaherpesvirus.

MeSH terms

  • Animals
  • Coinfection / veterinary*
  • Coinfection / virology
  • DNA, Viral / genetics
  • Disease Outbreaks*
  • Equidae / virology*
  • Gammaherpesvirinae / classification
  • Gammaherpesvirinae / genetics*
  • Gammaherpesvirinae / isolation & purification*
  • Herpesviridae Infections / epidemiology
  • Herpesviridae Infections / veterinary*
  • Herpesviridae Infections / virology*
  • Italy / epidemiology
  • Phylogeny
  • Respiratory Tract Diseases / epidemiology
  • Respiratory Tract Diseases / veterinary*
  • Respiratory Tract Diseases / virology

Substances

  • DNA, Viral