We currently have about 30 Production Reds that are close to 2 years old. We bought them "used" from another farmer who was downsizing, just to give us some eggs until our pullets are laying. Early in the summer they were giving us about 16 a day, they gradually fell to a dismal 4 or so, and are now back up to about 10 a day. Some of these eggs wind up Jumbo+! I have a dozen young roosters from our pullet set that I want to butcher soon, thinking about doing some of the old layers too - if I could pick up the poorer layers among them. When we bought the chickens (for $2 a piece), the woman was picking up and feeling some of the chickens and saying they were good layers (mostly her purebreeds), and kept them for herself. ...I'm not sure what she was feeling for! I am able to feel eggs inside some of the chickens, but I also know that I could be picking up a bird that is soon to lay but might only lay every 4 or 5 days, say. I think I've heard you can also look for moist vents? Any other tricks? (It's not a situation where we could easily mark each chicken and make "trapping" nest boxes, though). Thanks for the advice.
A little food coloring in the vent will give a tinge on the eggs with a few colors you should be able to sort out who is laying and who is not. Spent hens often also tend to loose color around face and if the skin on shanks or beak or toes was yellow depending on breed, it will fade to grey.
The ones with the most space between the pubic bones are usually better layers, as are the ones with the most room in the abdominal area. A good sized, moist opening as you mention is a great indicator of who is currently laying. In the trap nest thread, there is a link to a really old book with this info in it. I can see how you'd have trouble with that many hens in one place with the whole food dye and trap nest solutions. But you might have to split them into smaller flocks if you want to truly determine the best layers. I'll try to find that bookmark and post it here.
I would just keep the hens with big red waxy full combs, wide spaced flexible public bones, and wide wet vents. However, it can still be somewhat a challenge if the hens are laying 2x a week vs 6x a week, as they may still have the aforementioned traits. When I had a production only flock, I just replaced everyone at the end of their 3rd year unless there was probable cause to cull them earlier.
If it is a production oriented flock, replacing after two laying cycles is pretty standard fare. Yes, you might send a fair layer or two to the freezer, but realistically, production bred hens just were not created to be 300+ layers forever. It is quite normal to see production drop off rather sharply at 2.5 years of age or two full laying cycles. More heritage type birds can lay effectively for many years. The trade-off, of course, is that they start slower and lay 240 eggs per year, give or take. I keep both kinds. More heritage types for my enjoyment, but extremely high output production hens for the egg business. The latter get changed out somewhat regularly.
I glove up, insert digit, and actually palpate the next day's egg through the intestinal wall. I mark those who don't have one. The next night, I do it again to all birds and mark the ones who still don't have an egg that is palpable. I cull all birds who do not lay each day or every other day in peak season. I've found this to be the only fool proof and 100% accurate way to identify layers....the other known techniques have resulted in me killing some fine layers by mistake. Not anymore.... I have a flock of 5 yr olds and 2 yr olds and even a few 6 yr olds who pass this criteria each year. None of these birds are production breeds...they usually don't make the cut after 3 years.
