Humidity under a hen

[Kullas]

how does a broody hen keep the humidity at 50% during the first 18 days and how does she raise the humidity to 70% the last 3 days. We do this in a incubator but i was just wondering how a hen does it with no humidity gauge

 

[2txmedics]

Where did you read she keeps it at 57%? I read somewhere when I first went searching for info and now don't know where. But I read that a test was done and someone had put a gauge and it read that the first 18 days she keeps it at 38%. I'm curious also as its become questionable with my Ma and DH. She says she use to bate and filled her LG with water and turn it on and % was high from the start and got good hatches. So questioning what I practice and researched.

 

[Sunny Side Up]

It's always a marvel to me how these bird-brained broodies know how to provide just the ideal conditions for their chicks to develop & hatch. They know how close to press themselves onto their eggs & how long of a coffee break they can allow themselves each day, all dependant on the variations of the outside temperatures & relative humidity. They lose or pull the feathers from their breasts to make bare broody patches of bare moist skin to press against the eggs. I've never tried artificially incubating eggs but have heard all the stories of how difficult it is to maintain the ideal conditions. So I'm all the more impressed that my hens can provide those conditions all by their lil' bitty selves out in the back yard.

 

[Kullas]

Our indoor humidity stays around 30 to 40% whith the central heat and air going. so that makes me wonder if i need to add any water to my incubator until the last 3 days.

 

[walkswithdog]

Artificial incubation and broody incubation are two TOTALLY unrelated things.

A hen heats with body heat from the top - and generates a small amount of humidity from skin/feathers. She does NOT raise it at hatch. It is generally a constant.

An incubator heats with air. Air that is robbed of moisture as it is heated.

Air heating is not body heat heating. When you use heated air to hatch you have to add some moisture or the eggs are robbed of the water within them to too great a degree.

Whether anyone has to use additional humidity at hatch is dependent on their own micro-climate. I never push it over 50, and the hatch itself as chicks hatch and dry run it to 55-60.

Under a hen each hatching chick does emit some humidity that probably does assist the others, but in an open environment hens shift and it's lost, it never gets weirdly high.

They're apples and oranges. Enclosed and artificial and open and body heat based. That we can do it at all, by following rules carefully is really pretty nifty.

 

[Katy]

A hen "raises" the humidity the last 3 days of incubation by not leaving the nest. Almost always a broody sticks very tight to her nest the last 2 or 3 days and doesn't leave to eat or drink even.

 

[Kullas]

When a hen gets off the nest for 20 30 min a day the hunidity and temp drops. Would it be closer to natural to take the top off the incubator for 20 30 min a day?

 

[walkswithdog]

Artificial incubation does not correlate well to natural.

Trying to artificially incubate naturally is not going to work well.

Because of the LIMITATIONS imposed by artificial incubation including the hours even days it might take to re-establish consistent temps and humidity in an artificial incubator you would simply ruin the hatch.