Opinions on fresh air and incubation

[Susan Skylark]

What is your experience/opinion on fresh air circulation during incubation, especially during lockdown? I’m only on my third hatch so this is all new to me. I’ve played with 3 different incubators: a foam still air incubator with little plastic plugs you pull out of a couple vent holes (little giant, never used as was running 107F), a nurture right 360 with the little fan shaped adjustable vent, and currently a cheap Amazon incubator with no vent holes at all. I did one auto turner hatch and one hand turning hatch in the 360, the hand turning I hatched 24/28 quail (had some temp issues and turner issues with the first batch but still got 6/8). I read somewhere that hand turning is beneficial partly because it brings in fresh air in every time you open the incubator. I definitely think this ventless incubator benefits from being opened occasionally (humidity has been an issue so need to add water twice daily). What are your thoughts and experience on fresh air, how much is too much or not enough, does it contribute to chick health or increased hatch rate? Thanks!

 

[Ridgerunner]

I'm going partly by what I've read and partly from discussions with a poultry science professor that specialized in reproduction at one of the top rated poultry science universities in the USA. That's the University of Arkansas, Tyson has poured a lot of money into their poultry science department. I'm specifically talking about chicken eggs but I'd think this would generally hold true for all poultry eggs.

During the first several days of incubation the oxygen level does not matter. I've read that fresh air is not best for the first few days but I'm not convinced it actually hurts them. But as the embryo develops it starts taking in oxygen and giving off CO2 through the porous shell. Supposedly at about ten days it starts needing an exchange of fresh air for stale air. As the embryos develop that need grows.

Of course there are a lot of variables. Still air versus forced air, number of eggs developing, where the vents are and how many are open, and conditions in the hatching room. Many incubating troubleshooting guides list lack of ventilation late in hatch and during hatch as a possible problem causing death to fully developed chicks. They can't get enough fresh air to breathe.

Too much ventilation can possibly reduce the temperature in the incubator or make it harder to raise humidity for lockdown. One time when I put the lid back on mine the temperature was maintained but the humidity dropped quite a bit. I finally figured out the electrical cord to the turner was out of the groove it was supposed to be in so the lid was ajar. Once I sorted that out the incubator went back to working normally.

This is basically just my opinion but hopefully a slightly informed opinion. My Hovabator 1588 is a forced air with one vent opening. I leave that vent open from when I start the eggs until hatch is over. Since it is a forced air I'm not that worried about the embryos and chicks getting enough fresh air.

 

[Susan Skylark]

Always love the academic perspective, thanks! There’s a cool video where they take a fertilized egg and let it develop in a cup, if you look at the paper written on the subject the developing late embryos required oxygen supplementation or most of them died, and if you consider how much of a workout hatching must be, I totally agree that some fresh air is definitely desirable.