The condition where the contents of the digestive tract cannot normally pass through the intestines is called intestinal obstruction (intestinal blockage), primarily occurring in the small intestine. Mechanical blockage of the small intestinal lumen or irreversible changes in the normal physiological position of the small intestine (such as intussusception, incarceration, and volvulus) cause severe abdominal pain, vomiting, or shock in dogs. This disease develops rapidly and progresses quickly; if not treated promptly, the mortality rate is very high.　　　　1. Vomiting, abdominal swelling, abdominal pain, and no defecation.　　　　2. Frequent vomiting may lead to obvious dehydration symptoms in dogs.　　　　3. Due to intestinal obstruction causing accumulation of a large amount of gas in the intestines, the dog’s abdomen is visibly enlarged.　　　　4. In severe cases, there is progressive abdominal pain, the dog's body temperature will also rise, weakness, and sometimes shock occurs.