Does anyone know what would cause a chook to be pre-disposed to be a non layer? She's only a year old, and I've taken her to the vet - he said she seems perfectly healthy and happy. She's been wormed and flead, just doesn't lay! When we first got her she laid little weak shells and nothing else, but haven't seen anything in months. She's on a layer diet and has oyster shells in there too so shouldn't be a calcium deficiency. Anyone else in a similar boat? TIA!