we never candled the eggs. They get the eggs in from the breeder farms.. they are washed and disinfected. broken eggs or cracked ones are tossed. Once they go into the incubators that's it until they are moved to the hatchers. Occasionally an inspector may candle a small sample. But since they are in climate controlled rooms they have their system "perfected" if there is a bad hatch it's usually blamed on bacteria count. They used to aim for an 80 to 85% hatch rate. they actually have more than that hatch.. but any chicks that are not fluffed up and completely hatched when the racks are pulled to go to shipping are dumped. Other hatcheries may try to save them.. but in the meat bird industry they get tossed.
No filters on the fans. No dust collectors. We had to clean the tops and behind the hatchers because of the biddy dust. It would be several inches thick on top of the hatchers.. even deeper in the corners of the hatchers. Most would be swept off / out. the rest blown off with air hoses and then hosed off with water. scrubbed and disinfected. In the hatcher rooms EVERYTHING was disinfected. fans, misters, doors, walls, vent pipes...floors.. basically everything inside and outside of the hatchers. The hoses were much like pressure washers.. very high powered and we had to use extremely caustic chemicals. Once cleaned the lab would gather swabs and test for bacteria count. If it wasn't in acceptable ranges they would have to scrub and disinfect again.
There were 20 of the big walk in hatchers to a room.. two rooms of hatchers to be cleaned every day and each hatcher held 6 racks of eggs.
in the incubators everything would have to be scrubbed and disinfected .. and swab tests done again until they came up clear. Some of them would be pretty messy too if there had been any exploded eggs. During early incubation they would also close off the incubator rooms while they fogged with antibiotics and disinfectants. Everything on a timer and no one could go in until the foggers shut off.
