Garlic may not be the first thing that comes to mind when you think of air fresheners, but Clemson University scientists are finding that it works like a charm in poultry houses ... and may lower the cholesterol in eggs, to boot. "We're feeding the chickens about 3 percent of their diet in garlic powder to mask the odor of the waste," said Glenn Birrenkott, Clemson animal and veterinary science professor. "It makes the poultry house smell like a pizzeria instead of manure."