I once went to the yard of a very well known local greyhound trainer, This place was a shit hole and absolutely infested with rats. As for bedding i always used shredded wax paper on raised beds with a board across the front. All went to shit when the dogs were wet though as it stuck to the dogs and then dropped off all over the kennels as they dried, If you didn't keep on top of it, it would block the drains, I never used heating with fit adult dogs and they never suffered without it, But again mine were always kennelled together, so shared body heat,
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