title: Detection and characterization of porcine sapoviruses from asymptomatic animals in Irish farms.
abstract: Caliciviruses are an important cause of gastroenteritis in humans and animals. Molecular analysis of the polymerase and capsid genes of porcine caliciviruses, sapoviruses (SaVs) and noroviruses (NoVs), has demonstrated a broad range of genetic diversity but information on their epidemiology and pathogenic role in pigs is limited. In this study, 292 faecal samples were obtained from 4-5 to 8-9 week old asymptomatic pigs from four porcine herds in Ireland during 2005-2007 and were screened by RT-PCR using calicivirus-specific primers. Only seven samples from two porcine herds tested positive for porcine calicivirus. By sequence analysis of the partial RNA-dependent RNA polymerase (RdRp) fragment, six samples from one such herd were closely related to each other (>98% nucleotide identity) and were characterised as genogroup (GG) III (Cowden-like) porcine SaVs. These viruses demonstrated an amino acid (aa) identity of 81.3-98.6% to GGIII SaVs. Conversely, one calicivirus strain, 9/07/Ire (identified from a different herd in 2007), was distantly related to GIII SaVs and displayed 94.6-98.6% aa identity to rare K7-like porcine caliciviruses, representatives of a potential novel SaV genogroup (GGVII), described previously in Japan and the USA. Circulation of SaVs in asymptomatic animals might be a mechanism of virus persistence in porcine populations and should be considered with respect to understanding the epidemiology of these viruses in porcine herds.
authors: Department of Biological Sciences, Cork Institute of Technology, Bishopstown, Cork, Ireland.
authors: P J
authors: PJ
authors: Collins
authors: V
authors: V
authors: Martella
authors: C
authors: C
authors: Buonavoglia
authors: H
authors: H
authors: O'Shea
mesh_terms: D000818:Animals; D017250:Caliciviridae Infections / Q000662:veterinary* / Q000821:virology; D002353:Carrier State / Q000662:veterinary / Q000821:virology; D005243:Feces / Q000821:virology; D007494:Ireland; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D029341:Sapovirus / Q000235:genetics* / Q000502:physiology; D017423:Sequence Analysis, RNA; D013552:Swine / Q000821:virology*; D013553:Swine Diseases / Q000821:virology