Guinea Fowl eggs typically take 28 days of incubation at 99 degrees F with an ideal humidity level anywhere between 40%-50%. In reality they can hatch anywhere between days 26 and 29. The eggs must be turned at least 3 times a day but 5 is better.
You should never mix Chickens and guinea eggs as they require different temperatures, humidity levels an incubation periods. This is a common reason for failure when incubating Guinea eggs, to high a temperature bringing on an early and staggered hatch.
Temperature should be decreased by 1F on day 25 and humidity increased to 55% and stabilized for hatching. A stable humidity is considerably more important than the final figure achieved.
Lock-down should be on day 25. It is important to keep the vents open for the hatch-lings to be able to breathe during hatching and turn the egg roller off or stop turning the eggs..
We know from studies of 5000 guinea fowl eggs at a time in a commercial hatchery that the best temperature for incubation is 37.2 ± 0.1°C .
During incubating relative humidity in the range 40 to 64% significantly affected the total water loss and hatch-ling mass. Optimal relative humidity was calculated to be 48 to 52%.
The rate of ventilation significantly affected hatch rate. This is especially important when increasing humidity for the hatching phase when the practice is to close the air vents to increase humidity rather than increasing the surface area of the water in the incubator.
The age of the laying flock effects the final outcome. The best eggs are from birds in their second year.
Candling guinea eggs:Guinea fowl eggs are easy to candle. their shells might be thick but they are light in colour. Be sure to do it in total darkness.
Candle before incubation to check there are no faults with the egg like damaged air spaces, missing yolks or hairline cracks.
Candle on day 10 just as you would for chickens and remove any blood rings or clear eggs.
The air cell should always be at the big/fat end of the egg (Guinea eggs have a big round end and a very pointy small end).
Incubation at high altitudes:At high altitude make sure the initial humidity is 45% during incubation. Bring it up to 60% at lock-down. Guinea eggs are pretty forgiving. At higher elevations the temperature can be as low as 36.4C or 97.5F with no ill effects on the keets.
Hatchability:I have found guinea eggs to have a slightly lower hatch rate than hens eggs. It is not uncommon to have a hatch rate of 65% to 75% of set eggs whereas it may be closer to 80 or 85% for chickens eggs.
Hatchability of guinea fowl eggs starts really decreasing after 7 days. Cool eggs keep better but do not try to keep them longer than 10 days before incubating. Eggs for hatching should be turned regularly just as a hens eggs would be.
You don't want to put them in the incubator as soon as you collect them because you'll have a staggered hatch and that will mess with the humidity levels during hatching.
Turning eggs:Be sure to turn them 3 or 5 times a day. Odd number of times is best as this means the egg is on a different side overnight. Mark one side of the egg with a cross or line.
Dealing with rotten eggs:The bubbling liquid dots coming out of an egg is probably a rotten seeping egg that may explode at any time.
Place a bag over your hand like a dog mess bag and pick the egg up really carefully. Enclose and tie as fast as you can. Dispose of quickly. If it bursts it will stink enough to make you retch and will contaminate everything it comes into contact with.
What is lock-down:Lock-down is the last 3 days of incubation when you raise the humidity for hatch. The term lock-down actually means keep the lid closed on the incubator until the hatch is over and not lock the ventilation covers. You want that warm moist air to stay in there so the shells stay softer and the inner membranes stay moist.
Lock-down is also the time to turn the egg roller off or stop turning the eggs.
It is also common practice to add surface area to the water reservoir in the incubator at this time. Keets need the extra moisture to be able to pip, spin in the egg and unzip to hatch, especially in a forced air incubator.
Pipping:Pipping is when the keets that are developed far enough along to be ready to start hatching start pecking the inside of the shell and cracking it. Sometime it's just a crack at first, other times there is an obvious peck mark sticking up on the surface of the shell.
With pipped eggs I would always leave the incubator closed, stop fiddling with it and candling the eggs and just let them hatch.
You do want some fresh air flow coming into the incubator from the vents in the incubator, but the more cool dry air you expose the eggs to by opening the incubator the less of a chance there is of the keets hatching successfully.
Every time cool dry air gets to the eggs you run the risk of the inner membrane shrinking down over the keets, making it difficult or impossible for the keets to hatch, or even suffocating them.
Fertility rates tend to be in the 80% range. If yours are less than 70% I would investigate why.
Low fertility or hatch rates could be caused by:
1. Condition of the parents.
2. Age of the parents.
4. Poor storage of the egg before incubation.
5. Genetic problems.
6. Faulty incubator.
I hope you have found this useful.