Transmissible gastroenteritis (TGE) virus is a porcine coronavirus that infects the small intestine and causes vomiting and profuse diarrhea in pigs of all ages. It is an acute infection that spreads rapidly and has an almost 100% mortality rate in piglets under two weeks of age. TGE virus multiplies in the intestine and is shed in large numbers in the feces which is a major source of transmission either directly through the purchased carrier pig or indirectly through mechanical transmission. Diagnostic assays for detecting TGE include ELISA, PCR, immunohistochemistry (IHC), and histopathology.