Dry Incubation **NOW WITH PHOTOS!** - How Low is Too Low? 10% Humidity**ANSWERED: NO.**

[ChaddiX]

Hello Everyone!

I've got bantam and standard size eggs in a HOVABATOR 1588 Genesis and they've been in for 6 days at 10% humidity. Is that too low if I'm using Worrell's Dry Incubation method? I read the article and it's a little misleading as to what the actual hygrometer reading should be.

Thanks in advance,

CHAD

 

[ChooksChick]

ChooksChick, you might have to update your link...it's coming up as an error...

Welllllllllll CRAP SANDWICHES! I'll fix it.

Here: http://goo.gl/M2EWv

 

[they'reHISchickens]

In my limited experience, under 20% is too low. I get into those danger zones during winter hatches when the inside air is very very dry since we heat with a pellet stove. I had much better results in the 20-30% dry incubation range.

 

[ChooksChick]

ChooksChick,

Thanks so much for this info on dry incubation. I really appreciate your willingness to share your knowledge.

One question - in the beginning of your instructions you say to completely ignore humidity but the last paragraph in Q&A says to not let the humidity drop below 20%. Is this just for the last few days?
I'm asking because my hygrometer - before adding eggs - reads 10%

Kerri in NC

Excellent question- I've revamped my page a bit here and there, and I really don't use any hygrometers at all anymore, BUT I did notice toward the end of using one that my humidity would drop down to 10-15%- during the winter, especially. I stopped being concerned after testing several hatches and finding that even THAT wasn't low enough to cause a problem.

That being said, occasionally you'll have a batch of thin eggs, almost always WHITE, that will lose moisture faster than expected. Only in this case, when you find that the air cell is growing faster than you would normally see, would I be concerned enough to add water during the first 18-19 days.

Also- these instructions won't work so well with quail or other thin-shelled eggs. I do have to add water with those...but still don't own a hygrometer because I'm such a hatchaholic I can just tell...

KIDS, PLEASE- don't start, because once you start, you won't be able to stop.

(insert old 80's commercial with the egg here...only when they crack it open a chick pops out!!!)

 

[DanEP]

Iv'e had good result in my Brinsea eco 20 at about 25% on days 1-18 and then about 60=65% for lockdown(80% hatch rate. 10% might result in air cells that are to large . I 'd try and get it up a little.

 

[quintinp]

For standard chicken eggs. I use 30% humidity the first 18 days. I use 75% the last 3 days. I have had great luck with dry incubation! I got a 100% hatch rate the first "Dry Hatch" I did.

 

[AllenWMiller]

Okay so I’ve read all the posts in this string so now let an old man put his two cents into the mix.

First let’s get some terminologies ironed out. Understand that there is no such thing as “dry method” incubation. It is out and out impossible. If it were, a vulture egg in the driest desert would have no need for the female to tend the egg it would simply hatch from the heat. But it is tended and cooled and heated and humidity is monitored constantly by the female. (Remember humidity is one of the four critical factors for embryonic incubation.)

Second the method being referred to by some folks is referred to as “low declination humidity method” or LDH. And this idea is certainly not new to the poultry world. But in today’s world it has no place.

LDH was a methodology used in the 19th and early 20th century as a means to out gas incubators. Realize that the heat source for early incubators was fuel oil or kerosene. As a result if you ran the humidity too high the noxious gases could accumulate and suffocate the developing embryo whereas the lower the humidity the easier any trapped gas could be expelled via ventilation holes.

This type of incubation was complicated and time consuming and hatch results were terrible even by today’s hobbyist standards (50% or less to be precise). My forefathers used these units and their journals tell the tales of their successes and failures with them.

This lower humidity method ran the units in the 25 to 35% humidity range ramping up to 50% or so at hatch.

Today proper humidity management is as follows:

Room temperature/humidity: 70f plus or minus 2 degrees with relative humidity at 70% plus or minus 5% (this is the room where the incubator will operate)

Incubator values: 99.5f forced air plus or minus .1 degree 100.5 still air plus or minus .1 degree.
1st to 18th day 60% plus or minus 5%
18th to 19th day 65% plus or minus 5% (some will skip this step and go to 70% on the 18th day. I have had good success with this extra step)
19th to 21st day 70% plus or minus 5%

I have had friends and colleagues who use old redwood incubators tell me they have had great success running their humidity at values around 75-80% humidity. Wrong. They had great success because redwood incubators are the best units at absorbing and releasing water much in the same way a tree transpires naturally. In a redwood incubator the wood itself wicks away moisture and releases it back as the air in the incubator becomes dry. A lot like the wood expanding and contracting in our homes during various seasons.

And I have been chided for such hard and fast rules but they work. Can you tweak them? Yes. Can you tweak them to drastic levels? No. And here’s why.

First most of us have experienced drown chicks in the egg from too high humidity and chicks stuck in the egg from too low humidity. But how many actually understand the nature of the humidity in relation to the development of the chick itself?

Do we just assume it’s natural and that’s it? No. Humidity places a key and vital role in the development of the embryo. In fact, I see it as akin to a second womb for the egg. Proper humidity allows the easy exchange of air flow through the shell making it much easier for the developing chick to breath. Look at it this way, when the air is dry in winter doesn’t your skin dry out and your nose dry up when breathing the cold, dry air? Ever notice how much easier you breathe at the beach? (This is another old method of salting the water in an incubator but I will go into that in a later string)

Humidity is vital to the development of a chick much in the same way drinking water is a necessity for any living creature.

 

[[email protected]]

some one should see what the humidity is under a chicken.

 

[lucky123]

Mr.Miller has given the best advice you could ask for. This man has knowledge most of us can only dream of. I have been hatching a few years now, have tried many different ways, and find his advice to be spot on. One of my greatest tools in life has been to pay attention to someone who knows much more than I do!

 

[Alaskaduck]

A few more points on incubation:

Store hatching eggs no longer than 7 days between 40-65f (55-60f is optimal at 75% relative humidity).Remember that cell division in the egg occurs at 67f and above. The first cell division is completed about the time the egg enters the isthmus. Additional cell divisions take place about every 20 minutes; so, by the time of lay, several thousand cells form two layers of cells called a "gastrula." Once the egg is laid it cools and cell division slows or stops until proper environmental conditions are met.

Also remember the day you are setting the eggs in the incubator to allow the eggs to set in the hatching room for 4 to 8 hours to warm up to the relative room temperature of 70f and 70% humidity. This will prevent the cold eggs from sweating in the hot incubator.

One of the biggest failures in a foam hobby incubator is the lack of proper ventilation during the hatching process; particularly with automatic turners. We assume that since the eggs are being turned this is sufficient to tending the eggs. But as the embryo is developing it is taking in oxygen through the pores of the shell and likewise it is expelling carbon dioxide through the shell into the incubator.

If we allow the unit to remain closed for days this is tantamount to asphyxiation and is often the reason for a poor hatch. We must open a foam incubator several times a day albeit it briefly to exchange the air in the unit.

Prior to automatic turners for these small units we naturally opened them twice a day to turn the eggs. One time this rule should be suspended is during a power outage. In this case the unit should remain closed to conserve heat and humidity. The other time this rule is suspended is from the 18th through the 21st days when we stop turning the eggs and close the unit for hatching.

Hello, I'm new to BYC and hope I can jump in this older thread. Do you know when weighing became part of the process? Same time as candling? Before or after? I'm incubating my first eggs, duck eggs and I've been candling but also weighing. If I go off my weights, I'm afraid they haven't lost enough and I'm on day 24.