Size Different's in Barred Rock

[grimreaper]

I purchased 2 Barred Rocks in july. the question I have is that 1 of them has grow to be about 6lbs and the other is only about 2.5 lbs. The larger one has started laying eggs which was strange to me because I was sure she was a rooster. so why is there such a size different's in the 2 hen's

 

[GreenMeadows]

I have some screwnie RIR's and some not scrawnie. I guess it depends the breeding??

 

[Fred's Hens]

Difference is size between two birds, roughly the same age, is explained in many ways.

Genetic difference. One is from a large frame genetic background and the other is not. You cannot know the parent stock and on backward for generations.
Pecking order. Sometimes a smaller bird gets shoved down the pecking order and that has consequences as to feed intake.
Failure to thrive. Some birds simply do not thrive and in a professional flock or commercial flock, such runts are often culled.
Rarely, it is simply a matter of one being a late bloomer, although this is somewhat more rare.

These and other reasons explain the difference in one bird being large and another small. A Barred Rock at 2 1/2 pounds, at that age, is really, really small. The SOP for BR hen is likely well over 5 pounds. Personally, I like a BR hen to be near 5 pounds minimum.