When I lived in Champaign Illinois, the University of Illinois Agriculture Department had the strangest cow that they would bring out during campus open house. For some reaseon they had placed a port hole through the side of this cow so that you could reach your arm into its stomach and pull out partially digested food. The cow did not seem to mind that she had this extra port but the crowd had a mixed reaction, particullary when the cow would belch through the port hole (not a very pleasant experience. When they were done letting all the visitors group the inside of this cows stomach, they would scwer the cap back on the port hole and the cow would go back to its day to day life.