Beef, chicken, and pork are the cheapest most cost efficient animal proteins to produce. Its more of a matter of yield and fat content (eg. flavor). A single

Beef, chicken, and pork are the cheapest most cost efficient animal proteins to produce. Its more of a matter of yield and fat content (eg. flavor). A single beef steer can produce more than 600lbs of meat. You can't get that much meat from a lamb, goat, and deer combined. Heck you couldn't get that from 2 of each of them. So you feed 1 mouth and get lots of yield. Chickens are the easiest of the poultry to raise and most versatile for cooking. Almost everyone eats chicken, so high demand. Even people who "don't eat red meat" will eat chicken and fish. And then there is the pig. Easy to domesticate, produces delicious meat at a high yield... and Bacon. Lamb, if prepared properly can be very good. But beef, chicken and pork are much more forgiving. *grew up raising beef, chicken, and pork. Hunted deer. Had a pet goat (he was a jerk). Never raised sheep, but wouldn't mind having some lamb in my freezer.