Day 24 of hatching and a review of incubating

It's day 24 of the silver Wyandotte incubation period.  Despite checking three or four times a day, there is no change.  Not that it will make any difference how often I check.

I am starting to think that the remaining two eggs are not going to hatch. It could be a variety of reasons, so i thought it may be useful to write about some of the factors that can affect a hatch in an incubator.

• Time of year - hens will not naturally sit or go broody at the moment, spring is on its way, so hopefully a later attempt in middle of February will be more successful.  There is of course the possibility that the cockerel is not quite firing on all four cylinders, he may of course still be in hibernation mode.
• Quality of eggs - there is no doubt in my mind that quality at this time of year will not be as good.  The shells can be quite porous due to the feed being eaten being used by the hens for heat and new feather growth rather than producing eggs.
• Temperature of incubator and position - I have been told and read that even half a degree can result in late hatching and it could even result in a failed hatching.  It is also important to consider the location of the incubator.  If kept in a drafty position or somewhere that temperatures and humidity can fluctuate it can put strain on the incubator and even though they are designed to keep a constant temperature, it could result in subtle drops in temperate for short periods inside.
• Calibration of the thermometer - this is something I have not checked.  One way of checking you thermometer is working is removing from the incubator, and putting it in a bucket of ice.  This way you can check if it is reading 0 degrees.  If not, you can adjust your setting to reflect this.  The only problem with this method is that my incubator does not have a full thermometer in it so it would not work in my case.  I will just work on the basis it is set correctly.
• Humidity - in the UK it is certainty more critical in the last 3-4 days to get this correct.  I have recently heard of dry incubating, where the eggs are set without the use of water as we have high humidity in the UK.  Water is only used in the last 3-4 days when he increase in humidity is required.  I used water all the way through my incubation.
• Frequency of turning - I have an auto turning incubator, but if you don't and need to manually turn the eggs, its critical to turn at least 3 times a day, most suggest turning 5 times a day.  If you turn manually you need to ensure you mark the eggs so you know they have been turned.

Of course you can avoid all of this by using a broody hen, but who knows when a hen will go broody, and you are limited to 6-8 eggs depending on breed type.
Plus where is the fun and learning experience!

Thanks for reading