Eggs with a flat side and a hole or crack in them

[fluffyc]

Our girls are on chicken food pellets, and have oyster in the grain plus an extra bowl of it. They get fresh veggies and fruits every day. They are about 2 years old. Last year we had no problems. 1 egg per chicken a day on the average. This year they all are not laying daily and one of the brown hens lay eggs with a flat side and sometimes broke. Whats the problem???

 

[Ravynscroft]

I forgot the name that it's called, but it's caused by a 2nd egg entering the 'chute' before the first egg has finished forming... if it's once in a while, no biggie, but if it is often that hen may have a reproductive issue...