Changes in organ growth pattern associated with long-term selection for high growth rate in quail.

Data are presented on the pattern of organ growth in embryos from a line of Japanese quail selected for high growth rate and compared with those from a non-selected control line. The data reveal that the increased growth rate post hatching is accompanied by a more rapid early development of the digestive organs. It appears from these results that the "genes for" growth rate are the "genes for" early growth of the digestive organs.