Reptile & Amphibian Forums

I've had this problem a reptile eggs in general. I get what looks to be a good clutch which goes full term only to collapse a few days after the expected hatching date. When the eggs are cut open nothing but yolk - infertile. Mostly this has occured with bearded dragon eggs and a few select turtles, but this is the first time I've had it happen with snake eggs. Normally when I have infertile snake eggs they collapse within a week of being laid. I had my emory lay a clutch this year... out of the 6 eggs 2 appeared perfect (the others were obvious slugs). These two eggs were incubated and blood vessels were noted on the one egg when candled a couple weeks after being laid. All through the waiting the 2 eggs expanded and kept a healthy look to them. Actually the eggs expanded to a size that could have easily held 2 or 3 babies each. At day 61, the smaller of the two large eggs suddenly deflated and molded. At day 74, the other egg collapsed. Both eggs when cut open contained no snakes....just a chunk of yolk and fluid.

Does anyone know what causes infertile eggs to go full term like this and then at hatching time decide to let me know they aren't actually good ? I look forward to a hatching day and hate it when I find I didn't have anything at all to be looking forward to.
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PHWyvern

It's actually a really common time for the fetus to die. It still could be husbandry issues I can't comment on 'cause I've never seen your setup or what you do with your eggs, but the two most common times for death are right after hatching (or conception) as the zygote tries to turn into an embryo and it's just so malfunctional (chromosomal abnormalities, etc) that it can't survive. That's why most women actually concieve something like 2 pregnancies before before bringing the third to term
The second most common time for fetal death is right before hatching/birth, because up until that point it had been supported by a yolk sac (or placenta, in some cases) and had not really had to rely on itself being metabolically competent. With the onset of changes to help with hatching, the embryo has to become dependent on its own organs and often, they're not great. There's a suprising number of really bad mutations that can make is surprisingly far, and they're not always mutations you can see (massively malfunctioning livers, kidneys, etc). In this case, there's not really much you can do... we don't have much data for snakes with genetic disease, and in chickens if you're getting poor hatch rates you start slaughtering breeders

I think you misunderstand. I totally understand eggs going bad (infertile or malfunction) and even babies dying for one reason or another prior to hatching or shortly after hatching. That's normal stuff to expect.

What I am trying to figure out is this... It's normal for infertile eggs to go bad shortly after being laid - it's not normal for an infertile egg to go bad around the time when the eggs should theoretically be hatching.

I had eggs that for all intents and purposes appeared to be perfect in every respect, that went full term only to collapse at hatching time. There was NO animal inside those eggs - just yolk and fluid. The eggs were infertile the entire time but never gave any signs of it. What would make an infertile egg behave as if it were fertile, go the full length of incubation all the while still behaving like a fertile egg and then at the time when hatching would normally commence, finally go bad and collapse?

It's frustrating to get these types of eggs only to find out once they collapsed and were cut open that there was never any animal at all inside. I've had this happen with some eggs from a couple of turtle clutches and bearded dragon clutches, but it's the first time it's happened with snake eggs. I had high hopes for these emory eggs. They had tripled in size after being laid and when candled I could actually see blood vessels. Everything led me to believe these eggs were fertile, but in fact were not.
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PHWyvern

I don't see how that necessarily makes me wrong - the vasculature etc could all form with early embryogenesis, and then the embryo dies but the egg continues to function until it should hatch, at which point it collapses. You do see pregnancies like that in people - they basically keep the placenta, go through all the signs of pregnancy, but there's no fetus in the womb 'cause it died at some point after implantation.
The extreme increase in size makes me wonder if the humidity wasn't really high. Increasing 3x is way more than my rats have ever done.

I would think if they tripled in size there'd be something wrong with them. I think I've had eggs go full term with only yolk inside along with good ones. I think they are just infertile. As to what causes it, I'd review my husbandry technique. Maybe males haven't been cooled enough (just a guess).

Terry Cox

PS: I wanted to upgrade my photo gallery and have written twice to KS, because the form won't accept my username/password, and haven't heard anything back. Can you help?

Thanks.

>>Does anyone know what causes infertile eggs to go full term like this and then at hatching time decide to let me know they aren't actually good ? I look forward to a hatching day and hate it when I find I didn't have anything at all to be looking forward to.
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>>PHWyvern

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Ratsnake Haven...researching ratsnakes since 1988

Ratsnake Haven Group...an information providing list site.

>>I would think if they tripled in size there'd be something wrong with them. I think I've had eggs go full term with only yolk inside along with good ones. I think they are just infertile. As to what causes it, I'd review my husbandry technique. Maybe males haven't been cooled enough (just a guess).
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A couple of people have mentioned husbandry.
I think you might be missing the question.
It's obvious improper husbandry can lead to problems but it is also true that conditions which have proven successfull over time can also yeild a few "bad eggs"
It's not uncommon to have slugs, early egg collapses and babies that go "full term" but just don't have enough strength to hatch.
This is nature's way. They can't all make it. Anyone that tells you they have always had a 100% success rate would be extremely questionable to say the least.
I could see husbandry maybe if all the babies came out kinked or all the eggs died or all the babies made it to hatch time but died before they could exit the egg but not when you just have a couple of these weird ones.
I don't see how husbandry can cause eggs to appear viable up until hatch time, when they aren't.
The question, which none of us seem able to answer, is why these eggs that are obviously never viable and have nothing growing inside stay the same color, stay full bodied and appear seemingly viable up until "hatch" time.
Not what can cause them to go bad but what causes them to look healthy for 50, 55 even 60 days?

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Corn snakes and rat snakes..No one can have just one.
"resistance is futile"
Jimmy (draybar)

Draybars Snakes

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