INTRODUCTION (cont)
Dogs have also been used as models for study of the gastrointestinal system. Much of the classic work on intestinal motility, the role of the liver and pancreas in digestion, and GI surgery used dog models for investigation. Dogs have also been used for research in areas of organ transplantation, hemorrhagic shock, hemophilia and diabetes. The contribution to human health research has been significant.
As medical research has become more sophisticated more canine subjects have been bred specifically for research use. These dogs with uniform genetic composition and known environmental background are essential for some studies.
On the other hand, the genetic heterogeneity and hybrid vigor seen in outbred dogs from municipal shelters is preferred for many investigations since the information acquired from the research will be applied to genetically diverse human patients.