This spring I bought some new chicks because I figured I wouldn't get many more eggs out of my Red Sex Links which are now 3 1/2 years old. Guess I was wrong & glad of it! I'm still getting a 75+% laying rate out of the old girls which wouldn't be all that great except for the fact they lay some of the biggest chicken eggs I've ever seen! Anyone have any idea how much longer a large breed like these Red Sex Links might keep laying or how old they might live to be? Also, any idea how I might put a little more muscle & fat on their body for the winter? They're very tame & like being petted & they feel really boney compared to my newer girls that just started laying. I've tried giving them hotter feed with a little more fat in it but all they do is lay more eggs but not enough more eggs to justify the 25% increase in feed costs. FYI... No signs of worms or parasites & they were wormed this spring just as a precaution. Thanks!