I use hay at the moment but to be honest I wouldnt recommend it. I was adivsed to use hay as I keep my mice outside in a garage and was told hay was good for retaining heat. But I have had some serious respiritory problems which could be related to the hay and also my babies seem to be prone to eye problems although it does clear up after about 6 weeks of age I think this is caused by the hay as well.
My guess is that "Aspergillus" (a genus of mould and mould spores) is building up in the hay. Aspergillus mould spores cling and breed on natural materials such as bark, hay, straw and compost and cause Respiratory Infections in many animals (such as Birds of prey, rodents, cows and sheep). It is not nice at all and "normal" Antibiotics, such as Baytril, generally don't fight the infection as Aspergillus Infections (usually known as "Aspergillious") are very fierce. Symptoms of Aspergillious are watery eyes, sneezing, coughing, excessive "hacking", discharge around the eyes, itchy eyes, loss of appetite and weakness.
I didnt know condesation was bad! :| I've noticed thats been happening with plastic houses I've been getting as they'res 4 mice sleeping all together it gets stuffy but even when I put more then one house in they still choose to sleep together. :roll: Should I just give them the materials to make it themselves instead?
You could try the kind of bedding DomL posted as that will absorb most, if not all, of the humidity/moisture. I use it for my rattie boys and its great, I just replace it every other day and wash the old stuff out, put it on top of the cage in a sheet of paper and its dry for when its needed.
