I've been to some commercial breeders' place and saw the following 2 situations, just wondering which is worse for the roddents?

1. Use cage instead of tubs with no floor and bedding, so the urine and poo go directly to the pan under the cage. So the rats walk on wire!!!!

2. Use tub and bedding, but don't clean regularly enough (maybe due to too many in one tub) so the bedding and urine and poo gets piled up in the tub!!!!!!