WHY are they dieing at day 19/20

[speckledhen]

I have perfect, clean-as-a-whistle hatches when I keep my last three days' humidity between 65-70%. Before that, I keep it between 45-50%. If you put it up to 80% those last three days, you will drown the chicks. They also need ventilation, as they are breathing creatures. Some make the mistake of covering all the air holes around the bator while trying to get the humidity too high. Make sure your instruments are reading correctly, too.

 

[seriousbill]

Quote:
Me too, Cyn. I just had a pretty-faced little bantam hatch, as a matter of fact and am waiting on 3 more that have pipped. Hygrometer is reading 66%.

 

[ginbart]

OK OK I understand but, I am saying I did better with my humidily up. Sorry.

 

[Three Cedars Silkies]

"Humidity should be balanced with temperature; different temperatures require different relative humidities. Relative humidity should be 60 to 65 percent for the first 18 days of incubation, and 70 percent for the last three days. The water pan in the incubator should be kept full at all times. Use warm water to fill the pan. Humidity adjustments are made as discussed above in the calibration section."

"The relative humidity of the air within an incubator should be about 60 percent. During the last 3 days (the hatching period) the relative humidity should be nearer 65-70 percent."nn[url=http://www.ext.vt.edu/pubs/poultry/factsheets/8.html#L3C]


"For most eggs, a relative humidity of between 55 and 60 percent is adequate during the early period of incubation. During the 3 to 4 days just prior to hatching, humidity should be increased to about 70 percent.


http://extension.oregonstate.edu/catalog/html/pnw/pnw478/#anchor161806


These are some of the links that I was perusing, among others. You are correct about the last 3 days being about 70%. I must have been looking at the wetbulb temp as you said. However, the days 1-18 humidity is recommended higher than what I had read previously. One site recommends leaving the humidity at 55-60% until the first egg pips, then raising it to about 70%.[/URL]

 

[VanSintjan]

I kept my humidity on 75% during the hatch and it never dropped below 70%. The first 18 days I kept between 48 and 55% humidity. I checked the aircell when I candled the eggs. You can increase and lower the humidity during the first 18 days to adjust the size of the aircell. Here is a good link with a picture of how big the aircell should be during the different parts of the hatch: http://www.extension.umn.edu/distribution/livestocksystems/DI0631.html

This is also an interesting article about humidity: http://www.the-coop.org/cgi-bin/UBB/ultimatebb.cgi?ubb=get_topic;f=4;t=001808#000000

Good luck.

 

[seriousbill]

We've just got that

syndrome. You'll have to excuse us. Wishing you luck.

 

[speckledhen]

Different things work, depending on your location. For instance, if you are in the arid southwest it's much different than in the deep southeast where I am. So, there may be a slight difference in what you have to do to achieve the right balance within the bator. Seems some people never even measure humidity, just follow the bator instructions, fill the troughs at the appropriate times and things work out well. They never have a clue what their humidity is. So, like Janet said, we wish you all the good luck in the world!

 

[Three Cedars Silkies]

Speckledhen and Miss Prissy.... do you think a significant contributor to chick death is lack of ventilation?

I agree that it's tempting to close vents when the humidity begins to fall and I think I made that mistake my first hatch which led to 0%. Also, I was having temp swings to far in each direction which I have now fixed.

VanSintjan...I think you have hit on the best solution...checking the aircell and adjusting based on that info.

Who knows for sure? If the "experts" at various universities, extensions, etc. can't agree

...I'm sure we couldn't either!!

 

[poulet]

This could explain things! I have been closing the top vents to get the humidity up, I did open them when there was a chick that had been born but closed them again after I took them out, maybe there wasn't enough air . Have just set 13 more eggs in so we will see what happens this time , I will allways keep one vent open to see if that makes a difference.

 

[coffeemama]

Quote:
In my experience, humidity this high leads to sticky chicks. I have had high humidity a few times (over 80) and I had chicks that zipped part of the way then got glued to the shell with sticky membrane. I'm not saying it doesn't work for some, but if I didn't go in a rip the chicks away from the gluey membrane, they would have died almost fully zipped.