In animal housing you'll hear them saying that ventilation is good but you should avoid draft. what is the difference between the two?
Draft occurs when air flow comes in direct contact with the animals while with ventilation, the air flow does not come in direct contact with the animals. Draft should be avoided. Draft during cold periods can kill animals.
Some people think that chicks don't need air at all. That's wrong, chicks still need ventilation to help supply fresh oxygen and expel harmful gases like ammonia. What chicks don't need is draft.
Nice discovery. This is one of the little mistakes we make and blame the hatcheries for it.