Bovine coronavirus infections are associated with three distinct clinical syndromes in cattle: calf diarrhea, winter dysentery (hemorrhagic diarrhea) in adult cattle, and respiratory infections in cattle of various ages, including the bovine respiratory disease complex (shipping fever) in feedlot cattle.

BCoV has several structural proteins which have different functions in the viral cycle. Among them, the S protein, which consists of two subunits, S1 (N-terminal half) and S2 (C-terminal half), has several important functions during virus-host interaction. The S1 subunit is associated with binding to host cell receptors, whereas the S2 subunit is a transmembrane protein that is required to mediate fusion of viral and cellular membranes. Thus, it is important for virus entry and pathogenesis. Another importance of the S protein is its antigenicity. Antibodies induced by the S protein are highly neutralizing and are more stable during the course of an infection than those induced by the hemagglutinin-esterase protein. https://www.creative-diagn...