Re: Unemerged and ?non-viable brood???
"Bald brood" is not uncommon can be caused by rearranging the frames or pushing them closer together during inspections. It's also probably a symptom of other stress - robbing, weak population, dearth, disease. Worker bees that are too few, otherwise occupied, or too weakened to do a steller job. Address any stress that you can think of.
Don't worry about the bald brood it may be viable anyway, but will clear up when conditions improve overall.
5Y-25H-T-Z6b-0 winter losses in '14