The gastrointestinal (GI) tract is a complex organ that has paradoxical roles of digesting and absorbing food whilst acting as a barrier to pathogens. It is the
largest immune organ in the body and surveys ingested food antigens, reacts to potential pathogens, and interacts with a population of commensal microbes (the
microbiome) that appears critical to the overall health of the animal. It is also crucial to understand that signs of GI dysfunction may not be the result of a
primary GI problem. Diseases in other organ systems may secondarily cause GI signs, so the GI tract could be suffering collateral damage. The aim of the Canine
Gastroenterology textbook is precisely to give space to the explanation of this complexity.

The book is divided into six sections, starting with the diagnostic approach to specific clinical presentations that may or may not be due to GI disease, with each chapter including an algorithmic pathway. A section on diagnostic methods is followed by sections about the management of GI diseases and non-specific and specific drug treatments. The fifth section covers diffuse inflammatory, infectious and neoplastic diseases of the GI tract. Specific diseases of each area of the tract from esophagus to large intestine are found in the final section.