Generally speaking, the symptoms of canine distemper in dogs will go through three stages: the first stage, which lasts for 5-7 days, will enter the afebrile period, and there will be no obvious symptoms in the apyretic period. After 2-3 days, it will Entering the second fever; in the second stage, the nasal mucus will turn purulent during the second fever, and occasionally the trachea will be blocked, causing difficulty in breathing. The feces will be reduced and yellowish brown. If there is gastrointestinal bleeding, the feces will be loose and black; in the third stage, The body temperature remains the same or drops slightly for the second time, but the symptoms are not relieved, and spasms and twitches can be seen. Symptoms include thickened foot pads, inability to maintain balance when walking, and eventually death from failure.