Calves are susceptible to infection with the newly emerged porcine deltacoronavirus, but not with the swine enteric alphacoronavirus, porcine epidemic diarrhea virus

Fecal virus shedding, seroconversion and histopathology were evaluated in 3-7-year-old gnotobiotic calves orally inoculated with porcine deltacoronavirus (PDCoV) (9.0-9.6 log(10) genomic equivalents [GE] of OH-FD22-P5; n=4) or porcine epidemic diarrhea virus (PEDV) (10.2-12.5 log(10) GE of PC21A; n=3). In PDCoV-inoculated calves, an acute but persisting fecal viral RNA shedding and PDCoV-specific serum IgG antibody responses were observed, but without lesions or clinical disease. However, no fecal shedding, seroconversion, histological lesions, and clinical disease were detected in PEDV-inoculated calves. Our data indicate that calves are susceptible to infection by the newly emerged PDCoV, but not by the swine coronavirus, PEDV.