The Maya and Aztec didn't have any large farm animals, such as cows, sheep or pigs. So they reared chickens, dogs, turkeys and guinea pigs and then ate them for their meat.
The only people allowed to hunt for wild ducks, boar and deer, were the nobility.
Like most people around the world at this time, most ordinary Maya and Aztec would have eaten meat only rarely, and their diet would largely have been vegetarian.