2.1 Viruses and specimens
All viruses used in this study were either cell culture (CC) or clinical specimen (CS) (swabs, tissues and blood). Multiple CC isolates of the three CaPV members (LSDV, GPV and SPV) and the seven serotypes of FMDV (A, Asia1, C, O, SAT1, SAT2 and SAT3) were used. Other CC viruses include bovine herpes virus (BHV) types 1 and 2, PPRV, bovine viral diarrhea virus (BVDV), vesicular stomatitis virus (VSV) strains New Jersey (VSV-NJ) and Indiana (VSV-IN), and BTV serotypes 1, 6, 9, 13 and 22. All CC viruses were obtained from the biological repository of the Reagents and Vaccine Services Section (RVSS) of the USDA Foreign Animal Disease Diagnostic Laboratory (USDA-FADDL), located at the Plum Island Animal Disease Center (PIADC), Orient Point, New York, USA. The complete list of the viruses and their origins are shown in supplemental table 1. Clinical specimens used in the study were as follows: thirty five CaPV specimens (swabs, skin lesions, skin nodules, scab, EDTA blood) from sheep (n=10), goats (n=15) and cattle (n=10), experimentally infected with SPV-Nigeria, GPV-India and LSDV-Neethling, respectively, obtained from the Canadian Food Inspection Agency (CFIA), Winnipeg, Canada, as previously reported (Das et al. 2017b); thirty-six PaPV specimens (skin and scabs) from naturally infected sheep (n=9), goats (n=15), and cattle (n=12), obtained from the Diagnostic Services Section (DSS) of FADDL (DSS-FADDL) as previously reported (Das et al. 2017a); and thirty-nine FMDV specimens (tissues, EDTA blood and serum) from experimentally infected cattle, obtained from USDA Agricultural Research Services (USDA-ARS), PIADC. The PaPV specimens were collected from infected ruminants (sheep, goats and cattle) from different geographical regions of the United States between 2003 and 2005 that were submitted to DSS-FADDL to rule-out CaPV and FMDV. Negative control specimens (skin) were also used, and they were collected from healthy cattle.