I was awake most of last night worrying about this. I noticed a couple of times this white stuff that was mentioned. I feed the buns veg and hay everyday but I think I was going wrong with the hay, it is ordinary field hay. Timothy west is virtually non excistant in the UK, but a site called

www.bunnybazaar.co.uk

has some but like you Daisylover find it is extremely expensive. 1kg costs £8.50 approx which is around $12.00 I think. My old hay only cost 90p per bag, $1.40, so as you can see there is a great price difference. I also have 4 buns as well. But I have ordered some from the site as no shops here sell it unfortunately. Thanks to you both Meg(bunnicula) and Daisylover, thanks for the info on the subject. I only feed the rabbits a small amount of pellets anyway, so I am hoping changing there hay will make a difference.