AUSTRALIAN POULTRY FORUM™

Hey all. Greetings from Australia..

I have just been luckily given a lab incubator (water jacketed) it holds the temperature really really well at a stable 37.8 degrees. This is the model I was given http://www.thermoscientific.com/ecomm/s … reId=11152

This is my first ever attempt at hatching eggs using an incubator. (I normally use a broody hen)

My only concern is the humidity within the incubator. The water pan that come with the incubator is designed to run 95% humidity. To combat this I only have a small cup of water in there which i keep to measure the wet bulb temperature. It has dropped but is still a high 75-80%

Should I remove the water pan all together? as I belieive that this incubatior already draws air from outside which already has humidity in it? Has anyone had success with these? In melbourne.. outside humidity is approx 70- 80% I believe.

I dont really want to drill through the glass door to create ventilation ports. I dont think I can even if I wanted too..

Has anyone used these types of incubators to hatch before??

Any advice would be greatly appreciated!

Many thanks


Dave

Dave,

If the incubator has an even temperature and holds it well at 37.8 to 38oC, most poultry eggs will develop fine.

The key points are that you'll need to turn the eggs at least twice a day and that optimum humidity is about 40% for setting and 60% for hatching. Those % numbers are not incredibly critical, just be in that region.

Some air exchange is important too, but you would probably get enough during the setting phase by opening the door to turn the eggs.

During hatch, demand for oxygen goes up & so you may need to think how you can improve ventilation a little more.

Andrew

A couple of things you can try

Reduce the water or even removed it, I would remove it all together
Did you weigh the eggs first? and since?

I had trouble with humidity and found removing the pan was the answer

The usual method of humidity control is by controlling the surface area of water for evaporation.
Reduce the area to reduce humidity and increase the area to increase humidity.
This can be done by using a deeper container with a smaller surface area or a baffle to cover portion of the surface to reduce humidity or a container with larger shallower area or uncover completely to increase humidity.
What you do not want is for the water to run out and humidity drop by only putting a small amount of water in or by removing the water container completely.

I would normally agree but its obviously not evaporating at a high enough rate and I don't think reducing the surface area will help as it didn't work for me but he could try that and see?

To solve the problem , may have to think outside the square.
Might well be a case of trial and error until you find the solution.
Another possibility is to place a sponge in the water tray, humidity would be available when/if needed but by using a sponge in the tray evaporation would be reduced.
Maybe consider removing the water and giving the eggs a light spray with warm water at turning.
If the unit is sealed evaporation will be reduced drastically as to evaporate air flow is also required.
As suggested earlier airflow is & will be vital in the later/end stages of incubation and hatching.
Concentrating on the air flow issue might be the solution all round then adjust the humidity accordingly ??
I tried unsuccessfully to view the unit via the link posted, any chance of a photo to jogg the grey matter on a possible way around your problem.
Look forward to seeing the unit.

You'll need to get a wet/dry bulb or an electronic hygrometer to confirm humidity. Electronics stores or larger hardwares sell electonic ones that give a reasonable reading for about $40. I love the electronic one because it has nice big digits and I can see at a glance what the humidity is without having to read a wet and dry bulb.

Forgive me if I'm telling my grandma how to suck eggs here... if the outside temperature is 15oC and 80% RH, then by the time you heat that air to 38oC the RH will be just over 20%, thats because warm air can hold a lot more water than cool. So you will need some extra water in the incubator to get humidity to a reasonable level. Probably thats only a relatively small surface area of water.

You will need to solve the requirement for some fresh air entry into the incubator somehow.

Hey guys. I've removed the water tray and replaced it with a small saucer. I placed in a wet bulb thermometer and hygrometer to be sure. Humidity has dropped to 55-60 p.c which I'm pleased with. I've candled the eggs and they are progressing nicely. Hatching is due next Friday 7th of October. The unit sucks in air from outside and circulates it via a fan with an air filter over it. As it's my first time my only worry now is what happens once they hatch... Will there be sufficient oxygen for the chicks to breathe? I see a lot of people using fridges converted to incubators. I'm guessing this is a similar set up. Any who further feedback is greatly welcomed!

If its sucks in air from outside there should be no probs with air?

Just to let everyone know.. they hatch a treat.. 18 out of my 20 eggs hatched.