Regulation of digestive function in domestic livestock: intestinal absorption and exocrine secretions.

The title of this symposium, “Regulation of Digestive Function in Domestic Livestock,” should stimulate some readers to reflect upon events of a few years ago when fresh meat products were luxuries that were enjoyed once a week or on special occasions. What was the availability of fresh meat in the US. 50 years ago? The answer is that the availability of fresh meat was extremely limited. Public cold storage facilities were nonexistent; therefore, freshly drawn poultry, feathers intact, was delivered daily to small meat markets or butcher shops in cities. Beef was delivered daily, and, depending on the size of the butcher shop, usually one side at a time. Fresh pork was available in the winter and salt pork or cured pork was usually available. Fresh fish was only available to those who lived close to the sea or lakes; otherwise, fish was either smoked or soaked in brine. After World War II, large-scale refrigeration became available through home freezers, and rental freezer space (“lockers”) became popular in rural communities. This placed a new demand on the production of meat products of all kinds. Between 1940 and 1955, industrial and university research unraveled the mysteries of some of the water-soluble vitam i n s and growth factors. The baby chick was a favorite animal for bioassay on many of the vitamins, so those early experiments helped to pave the way for the expansion of the poultry industry. Another major contribution to the