Why Won't My Eggs Hatch?

[dazz02]

I made an incubator out of an old cupboard. It has 2 light bulbs to heat it up which is adjusted by a dimmer switch, i have trays of water for the humidity which i regularly fill up with distilled water. I also have a thermometer/humidity clock which informs me to the exact point of what the temperature and humidity is.

I have set 3 lots of eggs first time 6 second time 9 and third time 13

i have only had 1 chick hatch and that was from my first batch. In all attempts the chicks have developed but never hatched other than the 1 from my first attempt. The temperature is always between 37.5 degrees Celsius and 39 degrees Celsius which i have read is acceptable. The humidity is around 45%-55% in the first 18 days and i can increase it slightly by spraying water in during the last 3 days which can increase it up to 65%-70% however it may drop back down to the 45%-55% between spraying.

I think the ventilation may be too low as there is 1 slot between the 2 doors which open which is 1 inch wide and around 12 inches long, extra ventilation is added when i open the doors to turn the eggs. I am unsure whether this is enough? My worries are increased as my last 13 which i had in started to go rotten and smelt terrible. Even the ones which had chicks in started to smell so in the end around day 19 i through them all because i couldn't stand the smell.

My eggs which i use are home produced from my Rhode Island Reds and my cockerel which is an Old English Game.

Any help on how to increase the hatching rates would be greatly received before i start my next lot in a few days time.

 

[Lots A Cluckin]

I think you may have it too hot in there...next time try more like 37 degrees celsius

 

[ChickenPeep]

In addition to the above post, I think it's too humid. 55% is probably to high. If it's too high, the eggs won't lose enough moisture and will drown.

I would try 40-50% next time.

 

[Lots A Cluckin]

true...when I incubate...I try to target 40-45 for the first 18 and them about 55-60 at lock down

 

[dazz02]

And why do you think they started to smell do they need better ventilation?

 

[ChickenPeep]

I'm not sure. Did you crack them open? Maybe they weren't fertile at all.

 

[dazz02]

yes most of them were fertile and even those smelt bad, that's why i think the ventilation is bad

 

[satay]

I agree with the temps to high. I have mine at 37.5c and humidity for first 18 days at 45% then change it to 65% for hatch.

 

[dazz02]

what would you say is a maximum temperature for them to hatch? Also would a hen when she sits on them keep the temperature so accurate? i very much doubt it.

 

[satay]

I don't know the temp when a mother hen sits on them. I was just offering you advice on how i do it. From what I have seen over the years everyone is different when it comes to humidity they use depending on where they live but most that hatch successfully stick pretty much to those temps. Perhaps you are right with the ventilation being an issue with them being bad smelling I am not sure. Only time i had had a bad smell in the bator was when one had a crack in it but that one had not developed. Alot of the time with hatching it's trial and error take advice from others and use whatever bits of advice you think are relevant til you get a successful hatch.