Our son has a few egg layers that have been laying all season.He is now getting an egg from 1 of the hens that is very poor quality.The shell is thin,the yolk Breaks when egg is cracked into a pan and the white is runny. Does anyone know if this is a sign of disease or of poor nutritional values?I suggested Oyster shell For thin egg shell But I'm not familiar with What could be causing the other 2 things.Any help is appreciated