, had my heat lamps on for about 5-6 days, they deff do the trick, you can tell because the blankets they sleep on have stayed in one position, so the dogs have just stretched out and not moved in the night . im sure it helps them when they get to old bones aswel TBH I had an old lurcher bitch deerhound x, she wudnt keep any bedding down and lock her in her kennel and she d go bizerk so I used to leave the door on a jar and let her do her own thing coz she'd howl all fuking night otherwise, the fuking thing was a nightmare lol, and it defo took its toll on her she seemed to age a lo