US Food and Drug Administration (FDA) allows the use of carbon monoxide as a "preservative;" by attaching to myo-globin's iron atom, turning it bright red and preventing it from interacting with oxygen. This practice is banned in Europe and Japan, because even though it might prevent color changes, it certainly doesn't prevent bacterial growth.
80% of the antibiotics sold in America are fed to animals raised in confined animal feeding operations (CAFOs). The antibiotics and GMP grains radically alter the bacterial balance and composition in the animal's gut. Just as in humans, poor gut health in animals promotes disease.