my 4 or 5 wk old babies are in a rabbit hutch for a brooder. they've been going stir crazy. yesterday i moved their hutch out of the hoop house where they were living & into their own pen separated from the four big girls so they could have to ground time. i had been trying to figure out a way to keep the hutch warm during the chilly nights. we had to replace our central air conditioner the other day (OUCH!). the heavy cardboard box fit over the brooder like a glove. i raised the hutch on bricks & put the heat lamp under the hutch on a metal grate. covered the whole thing w/heavy cloth drop cloths we had. last night it was in the upper 40s. it kept them warm @ 74. i worried & fretted & checked it a dozen times & all went well. the lamp heated the metal floor which helped radiate warmth throughout the shavings in the hutch. two lights was too much. i cut two peek a boo holes (4" x5") in the cardboard box on each side so i could see the babies & the thermometer and to provide ventilation. the last time i checked them was 3a.m. when i went out at 7:30a.m. all was well. tonight will be another run. hope it goes as well.