Photo Credit: podchef
The most common breed used for meat is the Cornish White Rock Cross (Cornish X). In fact, it's the chicken that you find in the cellophane package at the grocery story which was popularized by Donald John Tyson in the mid '60s. The breed certainly has some advantages since it rapidly gains weight and is ready for slaughter in 8 weeks at roughly 4-5 lbs. dressed. If you're looking to save a few dollars on feed, this would be the way to go!
However, there are some negatives to the Cornish X. They will literally eat themselves to death if you don't ration feed. Constant feeding causes their bodies to grow so fast their heart can't handle the strain and they'll die of heart failure. In addition, they get so heavy that they'll lay down to eat. And if it's hot, sometimes they won't even get up to drink water and will die from the heat. You should also know that the chick mortality rate is a bit high as well. The breed is easily stressed to say the least! All in all, you should figure on about a 15% flock loss before you ever get to slaughtering.
There is an alternative; heritage breeds which mature at a slower rate. The benefits include healthier birds and better tasting meat, but you are going to pay for more feed since the birds are raised for a longer period. And they will still be somewhat smaller when dressed out. These birds are suited better for pasturing which could be a cost benefit if you have the space.
The American Livestock Breeds Conservancy (ALBC) is working to preserve some of these disappearing birds along with other animals. Their list of breed requirements include: a genetic line that can be traced back several generations (and is recognized by the APA), the ability to mate naturally and remain true to type (Cornish X cannot), the ability to live a long, productive life, and a moderate to slow growth rate.
Slower growth breeds are highly prized by the French who love a good meal! They've developed a whole program called Label Rouge (Red Label) to certify chickens that meet their stringent requirements. This isn't one breed, but rather various breeds raised according to traditional animal husbandry practices. A Cornish X would never make the grade from the beginning because the breed itself does not fit their criteria. However, several other breeds, if raised according to their standards, could qualify. Word has it that these birds are quite tasty, so you might want to give this method a try with the right breed!
For a complete list of Heritage Breeds recognized by the American Livestock Breeds Conservancy you will want to go here. It's a lot of information, but well organized! Also, you can download a list of breeders at the ALBC as a pdf file. And, J.M. Hatchery sells Freedom Rangers which is an excellent option. Dale over at Backyard Farming is raising a batch of Freedom Rangers alongside some Cornish X to compare the two. He even has videos of the process! There are three so far, so be sure to see Videos 1 and 2 as well as Video 3. Should be interesting to watch over the next several weeks!
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