Although it sounds esoteric, the feed conversion rate is at the heart of raising a sustainable chicken. Also known as the feed to meat ratio, this number is simply the pounds of feed given to a chicken divided by the weight of the cleaned carcass.
The sad truth is that the feed conversion rate for chickens raised by nearly all backyard hobbyists is two, three, or even four times as high as the ratio for industrial chickens. Yes, you do end up with a higher quality chicken that lived a happier life if you raise it yourself, but that
chicken will not only take more money out of your pocket than buying one from the store would, your homegrown chicken will also have a larger environmental footprint. In my mind, that’s unsustainable.
Let’s look at some feed to meat conversion ratios:
- 2 : 1 — what the industry claims they get for factory farmed Cornish Cross.
(Hard to tell if this is true. My other numbers come from extension service websites or my own experience, both of which I trust more.)
- 3.5 : 1 — what you can expect to get from pastured Cornish Cross in optimum weather.
- 5.2 : 1 — Freedom Rangers on pasture, again optimal conditions. (Other “slow” broiler breeds are in the same ball park.)
- 6.2 : 1 — Our Dark Cornish at 12 weeks last year.
You’ll notice that pastured chickens actually eat more feed to reach a certain weight than they would have eaten if they were confined. (Side by side experiments have confirmed this.) Although we think of
pastured chickens as getting a lot of their nutrition from wild food,
chickens can’t digest much grass, so what you’re really counting is how many bugs your birds found. It seems to take broilers more energy to find bugs than they get from eating those bugs, thus the lower feed conversion rate on pasture.
Although these numbers seem very disheartening, I hope they don’t make you turn to supermarket chickens. As I’ll explain in a later post, I think that homesteaders can grow heritage chickens at nearly the same feed conversion rate that you’d get from Cornish Cross on pasture (and maybe even better) if we’re willing to think outside the box.