Anecdotal, about chickens.

My chickens egg laying slowed down to almost nothing this late summer/fall. I only had 3, so a bag of food lasted a while. I always bought the same brand/type of feed for them. They were only 2-1/2 years old. Sadly, I decided to get rid of them rather than see them through another cold northern winter.
Now I find out a bunch of people have experienced the same thing.
One thing I noticed about my girls, their eggs changed before they stopped laying. The color and shape of the eggs started to vary. When you only have a few chickens, each a different breed, you come to recognize their eggs quite easily.
This is very weird. Sorry, girls, I wish I had you back.
I'm interested in anyone else's experience with their chickens/eggs, if anyone would care to comment.