About two weeks ago my family rescued 3 hens from a free range egg farm, after they had just turned 18 months old and were then going to be sent to slaughter. One of the hens recently has had a complete change in her appearance and personality. Her comb is floppy and slightly purplish at the top, and she seems to bury her head in her neck. She isn't drinking or eating unless food is given to her directly and still she only eats little. She seems to be very fatigued and tired, standing by herself in a corner of the garden. Other two chickens are fine and leave her alone. I don't know if this is related but the last egg she laid was very pale and had a blueish tinge to it Does anyone have any suggestions to what her symptoms could be pointing to? This has only been happening since yesterday and she hasnt improved. Should I isolate her?