my chicken was fine this morning but after laying an egg she was lying down and cant use her legs,although she can grip with one of the claws, shes eating pooing and drinking fine and is alert but can stand. i took her to the vet who knows a tiny bit about birds,she checked her over,did temperature etc and said shes fine theres no explanation, ive got her in my kitchen in some straw and gave her some vitamin e with selenium. but can anyone advise me please? thankyou!