Breeding for size

[hawsecav19d]

I have always like large chickens and am wondering if you can breed for exceptional size or is it pretty much random? I had a Buff Opt that at 3 years old topped scales at 22lb when I was in FFA in the 8 years I had him only 1 of his sons out of more than 50 ever came close to his size and he topped out at just smidge over 19lb but most where in the 12-14lb range. 15 years later I am starting chickens again and went with Light Brahma and at 10 months I have 2 roosters ones at 12 and others at 14lb I expect them to grow for anouther year so waiting to see which I keep as full time breeder. I have several larger than standard hens same age as the roosters.
Is there any health reason to not breed for size if its at a slow pace? I understand that most breed for standard but is it a health reason or more cause that is what people want? I see pages on here show your biggest rooster cause people like showing off big ones, is it possible to line breed for a larger chicken over a decade so that its more than just random chance?

 

[Sydney Acres]

I have always like large chickens and am wondering if you can breed for exceptional size or is it pretty much random? I had a Buff Opt that at 3 years old topped scales at 22lb when I was in FFA in the 8 years I had him only 1 of his sons out of more than 50 ever came close to his size and he topped out at just smidge over 19lb but most where in the 12-14lb range. 15 years later I am starting chickens again and went with Light Brahma and at 10 months I have 2 roosters ones at 12 and others at 14lb I expect them to grow for anouther year so waiting to see which I keep as full time breeder. I have several larger than standard hens same age as the roosters.
Is there any health reason to not breed for size if its at a slow pace? I understand that most breed for standard but is it a health reason or more cause that is what people want? I see pages on here show your biggest rooster cause people like showing off big ones, is it possible to line breed for a larger chicken over a decade so that its more than just random chance?

Yes, you can definitely line breed for large size. Realistically, you can line breed for almost anything, depending on how patient you are about seeing results. But in breeding for something significantly different from the Standard, you have to be very careful, as unintended consequences often show up. There's the large animals that have an adequate constitution to support that size, and there's the large animals that hopefully do great through young adulthood, but with middle age have significant health problems, poor quality of life, and poor longevity. Growth rate certainly has an effect on that (just look at the Cornish X), but even slowly growing animals can outgrow their structure, compensate with the vigor of youth, but spiral down fast in adulthood. Issues such as joint conformation, ligament and tendon elasticity and strength, leg/pelvis/back conformation, heart strength and capacity, etc are all issues that are highly stressed with increased size. Not saying that it can't be done, but it's important to really watch for quality of life, vigor, general health, and longevity issues, in addition to just final size. Not doing yourself any favors if you end up breeding a bird that takes 1-2 years to mature, but has the health problems of the Cornish X when it's finally grown. And don't forget to select for a good temperament also. The bad boys are bad enough when they're only 8-10 pounds -- it's really annoying to have a 14-18 pound crazy rooster attacking you. If you're really interested in large sized birds, the Brahma and Jersey Giant are fabulous breeds, as are the heritage turkeys, and they are all in need of dedicated breeders that will carefully breed to the Standard, huge size and all. (And there's nothing quite like having a 35 pound tom turkey playfully explore the inside of your coat pockets when you walk out into their yard, not because they're bad, but just because they're tall, and they can.)