Figure 2: The M gene copy number mean ± SEM of virus shed in nasal passages for mock-inoculated (◯), Ca/WY-inoculated (▲), Ca/WY sentinel (△), Eq/CO-inoculated (◆), and Eq/CO sentinel () dogs. The minimum detection level of the real-time RT-PCR was 1000 M gene copies per reaction corresponding to 103 TCID50 of Ca/CO-1 and is represented by the dashed line.