There have been several reports on damage to chicken owing to insufficient hatchery hygiene. Chute and Gershman (1978) reported that the microorganisms that were isolated from the air in a hatchery were found in chickens with omphalitis. In addition, Devos et al. (1966) suggested that the Escherichia coli infection of chicks may have been associated with high levels of Enterobacteriaceae in the fluff. Effective sanitation programs should be devised to reduce the bacterial contamination in the hatchery.