I have a group of 15 hens in the DFW area of Texas. They are 9 months of age (1 groups) and 18 months (the other group). Starting in April they have all stopped laying. I went form 10 eggs a day to 2. Some days just one egg. I have the, on 20% protein feed and nothing has changed. They do not have worms(i have combed through heir poop). I'm frustrated and worried as what to could be going on.