I have 6 hens, 1 Dorking, 1 Austrolorpe, 2 Buffs, 1 Easter Egger, and 1 Cuckoo Maran. they were consistently giving me 5 eggs per day all through the winter, and for the last 3 days, NO EGGS. My first thought was predatory snake. But I have kept them in the chicken house which is snake proof, and still no eggs. I find it odd they would all quit at once. Any ideas? They eat NON-GMO layer feed, and there has been no change in anything!