Two of my chickens have had diarrhoea for months and I have literally no idea as to why. The sicker of the two had antibiotics from the vet which didn’t help she sadly she then got killed by a fox. The other chicken has a red comb is active and eating but is doing these spurts of that are almost pure water and she hasn’t laid for several days. I’ve done a worm count it’s didn’t indicate worms but I’m wondering whether I should try treating for worms anyway? I gave pro biotic and tried changing the food neither helped. I am very worried, she is my favourite Hen. Any advice gratefully received.