The following is an article from Uncle John's Unstoppable Bathroom Reader.
(Image credit: Flickr user Ed Schipul)
What would Porter the Wonder Dog have eaten 200 years ago, before there was Alpo or Dog Chow? Here's the history of the multi-billion-dollar dog food industry.
* More than 2,000 years ago, Roman poet and philosopher Marcus Terentius Varro wrote the first farming manual. In it he advised giving farm dogs barley bread soaked in milk, and bones from dead sheep.
* During the Middle Ages, it was common for European royalty to have kennels for their hounds. Kennel cooks would make huge stews, mostly grains and vegetables with some meat or meat byproducts -the hearts, livers, and lungs of various livestock.
* Dogs in common households had meager diets. They were fed only what their owners could spare. A normal domesticated dog's diet consisted of crusts of bread, bare bones, potatoes, cabbage, or whatever else they could scrounge on their own.
* In the 18th century, farm dogs, which had to be fairly healthy to do their jobs, were regularly fed mixes of grains and lard. In cities, you could make a living by searching the streets for dead horses, cutting them up, and selling the meat to wealthy dog owners.
* There were exceptions: The very wealthy, throughout history, have fed their pet dogs fare that was much better than what most humans ate. In the 1800s Empress Tzu Hsi of China was known to feed her Pekingese shark fins, quail breasts, and antelope milk. European nobility fed their dogs roast duck, cakes, candies, and even liquor.
The in the mid-1800s, the Industrial Revolution created a growing middle class with more luxury and more leisure time, pets began to be regarded as "luxury items" by everyday folk. Result: pet food became more closely scrutinized.