SUMMARY:The role of cuticle (mucoprotein layer on the egg shell) in preventing spoilage of eggs by microorganisms was studied. Eggs collected from the uterus or eggs treated with 5% EDTA solution to remove cuticle spoiled at a much faster rate than the normally laid eggs. The weight of the egg shell and its membranes did not affect the spoilage of eggs collected from the uterus. The protection provided by the cuticle was found to last at least up to 96 hr after the eggs are laid.