Poultry Talk Ontario (pto.ca)

I had 8 eggs begin to develop in the incubator (out of 20 set but I believe the 12 non-starters just weren't fertilized)
Of the 8 that began developing 5 quit in very early stages- I'm guessing day 4-5-enough to see a tiny blob on the yolk and a faint blood streak when I cracked them open. The 3 remaining are still going strong at day 13 and I think I will toss them under broody Stella and see what happens. From you more experienced folks what would be the predominate reason for early quitting? I'm going to throw another batch in the bator and see if the same happens.

Are they from outside in the coops? I almost wonder if they got cold or damaged in some way so the weren't viable and quit. I sometimes get a couple do that even later in the season. Parental nutrition is another reason but I doubt it. What eggs were they?

that is likely either cold damage or the eggs being knocked around a lot before collecting. if the hens were very rough with them or they got banged around before collecting....and somehow didn't break.....other things that you can see when candling are hair line cracks in the shell, those will usually quit quite early because of moisture loss near the cracks. the other early quitter fault is genetics....just something plain wrong so the chick doesn't pattern right and fails during the major patterning event (making the spinal cord and head/front vs tail/back) which occurs by day 3-4

Thank-you ladies. KB they were my eggs from the coop. I knew fertility wasn't going to be great but was itching to try anyways. What you both suggest about getting cold makes sense. I tried to only use eggs that I knew hadn't been sitting out there long but I'm sure some snuck in. The only other odd thing was that of the 5 that quit a couple of them had a thick mucousy, clear glob...it just looked like egg white but much thicker. Not sure what that was.

Thats usually bacteria that has gotten into the white and turns it really gooey-or a part of the white that froze (ie sitting on cold concrete-didnt freeze all the way but partly) and it change the structure of the proteins because of the ice crystals forming

Thanks @WLLady !
I'm not sure what I would do without this site.
Stumble through chicken keeping oblivious to what was happening under my nose lol!

well, frozen bits don't usually happen in april in my experience......LOL. but this year i've had totally frozen solid eggs all the way through to fine...i broke one open the other day just to see if it was fertilized and the yolk was thick, creamy and half solid! in april. and it was -10 outside...but. still.
i'm glad the forum is helpful LOL.

I agree with above, probably froze a little.