Coronavirus associated with an enteric syndrome on a quail farm

Abstract

An enteric syndrome was observed in quail (Coturnix coturnix) semi-intensively reared for restocking in Apulia (southern Italy). The birds showed depression, severe diarrhoea, dehydration and reduced growth. Mortality occurred particularly in young birds. At necropsy the prominent lesion was enteritis. A coronavirus was detected by electron microscopy and reverse transcriptase-polymerase chain reaction in the faeces and in the intestinal content of the dead quails. The virus could not be cultivated in chicken embryos. By sequence analyses of a fragment (409 nucleotides) of region 1b of the polymerase gene, the quail coronavirus displayed ≤93% nucleotide identity to avian coronaviruses (group 3 coronaviruses)—whereas by analysis of the S1 portion of the spike protein-encoding gene, the quail coronavirus displayed 16% to 18% amino acid identity with infectious bronchitis virus, and 79% to 81% identity with turkey coronavirus. Altogether, the findings suggest the existence of a novel coronavirus genetically related to turkey coronavirus.