32 out of 72 eggs hatched... ideas please!

[Orangefish]

Its been a week or two ago now but last month I set 72 eggs for a friend of mine. Come hatch day only 32 hatched, I was suprised because I had other eggs in the bator that came from my own chickens and I had a 90% hatch rate on those and they were all set the same day. I took the unhatched eggs out of the bator after a week and cracked them, ALL were fully developed! What could have happend, she feed Purina for her laying hens and I know Purina fortifies the feed with calcium for stronger shells... could the shells have been to hard for them to pip?? I have no idea, but I was just looking for suggestions because she gave me 72 more to hatch for her and if it was something I could fix then I would!!

I have an redwood bator, eggs are turned 3 times daily manually. Temps stayed right, no spikes or anything. All but 3 of the eggs were fully developed, the 3 that werent were just ones I missed when I candled because they werent developed at all. These chicks are red sexlink, black sexlink crosses.

 

[midget_farms]

That's a tough one.

What is the air flow like in your redwood? I built my own & have found that I have too much ventilation. The humidity & temps are good - but because the air turns over so much it tends to dehydrate my eggs. This is now my third hatch & I just figured this out 2 days before lock down.

In any case - if you have too much air turn over they can dry out even if the H is keep correct.

Just a thought.

 

[rebelcowboysnb]

Did you candle? Id so how did the air sack look compared to your eggs?

 

[Orangefish]

I did candle, I didn't notice unusually small air sacs but im no pro at this! I've only done about 6 or 7 hatches.

 

[steffpeck]

I have had a horrible time hatching sex-link cross chicks. I have tried hatching probably 20 sex-link cross eggs, and I have only had 1 hatch, and I had to help it out, and my luck it turned out to be a roo. The others were fully formed chicks, just never hatched. The other eggs that were hatching with them from different breeds hatched just fine. I wonder if there is a lethal gene somewhere that causes the chicks to die. I finally quit trying to hatch them, because it was so depressing to find perfect chicks that just died for no apparent reason.