The pyloric canal, also known as the canalis pyloricus, is the opening between the stomach and the small intestine. It can be termed as the exit point of stomach and entry point into duodenum (first part of small intestine).
Chronic Hypertrophic Pyloric Gastropathy or pyloric stenosis is a canine stomach disease in which the muscle at the exit of the dog’s stomach (the pyloric sphincter) become very thick. This results in slowing down or complete blocking of the dog’s digested food from traveling from the stomach to the intestine.
Where the stomach empties into the duodenum, there is a circular, valve-like muscle called the pyloric sphincter. The pyloric sphincter constricts and dilates to regulate the flow of food from the stomach into the small intestine. Occasionally, for unknown reasons, the pyloric sphincter constricts or spasms, causing an abnormal narrowing (stenosis) of the entrance into the small intestine. This abnormal narrowing of the entrance into small intestine is known as Plyloric stenosis or Chronic Hypertrophic Pyloric Gastropathy.
The condition can be congenital (present at birth) or acquired later in life. Some breeds are predisposed to congenital pyloric stenosis such as boxer, Boston terrier, and bulldog. The acquired disease, on the othe hand, is more common in the Lhasa apso, shih tzu, Pekingese, and poodle. Males are also more predisposed to this disease than females.
Signs and symptoms are directly related to severity and extent of pyloric canal's narrowing. Intermittent vomiting (often several hours after eating), loss of appetite, and weight loss are the common symptoms associated with this condition. The vomitus may contain undigested or partially digested food. In addtition, vomiting does not settle with drug administration.