Why Grass-Fed, Grain-Free Chicken Doesn't Exist (VIDEO)
If you've watched the video above you might have noticed that I skirt the topic of geese. My whole argument is that chickens are not physiologically suited to a diet of grass alone, that their simple digestive system isn't up to it. I contrast them with cows, which have a complex, four chambered stomach to efficiently break down vegetation. Yet geese have no specialized organs that differentiate them from chickens. So what's the deal?
For one thing, the digestive tract of geese is scaled up. It is longer than a chicken's, and the gizzard of a goose is capable of creating farm more pressure than that of a chicken, which more effectively crushes grass. Geese also have incredibly quick digestion, which allows them to consume a comparatively large volume of forage.
Finally, it's no coincidence that geese like golf courses so much. Because they lack all the tricks that allow ruminants to extract nutrients from tough grasses, geese must find very short, very nutritious plants in order to get enough calories. So you couldn't use a flock of geese to manage pasture the way you can with cows and sheep.
That said, geese are interesting animals. I raised them once, mostly on grass, and I don't plan on doing it again. They're very pushy, they're incredibly difficult to pluck, and at the end of the day I had a bunch of goose to eat.