Reptile & Amphibian Forums

Hello everyone.

I have succesfully bred Testudo Graeca over the last 12 years and I still some questions about incubation raise.

The particular problem I wanted to ask you about is those eggs that are overdue and are clearly fertile. I usually notice some little scratches under the surface of the egg before they hatch. As I have already said, every year I have some fertile eggs that don't hatch and after 4 months or so I crack them I find half-rotten embryos.

My question is:

has anybody tried to crack an egg once is due to hatch and there is clear evidence of the movement of the embryo inside the egg, I mean, those little scrathes.

This year I have got 6 eggs in this situation and I don't know what to do. I hace never dared to crack them.

Many thanks,
Marcos

You mean like this.
When needed I do this regular, but you do need a steady hand.

Basic tools required,....shaped pointed knife to score the outer shell, tweezers of differing "ends", good eyesight.
The object is to score the outer shell surrficient to form a scratch at least half way along the longest side (oblong eggs. Then with great care you have to then collapse the shell either side of the line, which should give way along the scratch. Once this is acheived, WITHOUT DAMAGING THE INNER THIN CLEAR SKIN LAYER WHICH CONTAINS THE BLOOD VESSELS you remove the broken shell using the variuos tweezers.
At this point if you can see an egg yolk I would leave the embryo alone but ensure that a regular supply of new/fresh air is allowed to reach the tort. This seems to spur them onto absorb the yolk at a slightly faster speed, usually 3-5 days.
I also "dribble" clean warm water over the skin to ensure it stays moist, other wise it becomes "rubbery".

Easy really, ;o)

graham(UK)

Do you often do this??? do they usually hatch without problems??? Are the hatchlings healthy???

Thanks in advance

I only do it WHEN I'm sure that they are more than 10days overdue or that the "scratch marks on the inner walls" indicate a problem (perhaps too low a humidity)within the incubator.

So far I've "helped" approx 6 eggs out of approx 100 fertile eggs, & I've had 100% success, but I DO HAVE A STEADY HAND.

It is far better to let nature take it's course but like me if you want ever tort to survive you must intervien on occassions.

If you get it wrong there's no one to blame except yourself. I'm not advercating that you should do what I feel confident at doing.

How many days overdue are your eggs?

graham(UK)

Many times an egg will not hatch when we 'expect' it to. But I sure don't recommend opening them.
A couple of weeks back I posted a photograph of a hatchling redfoot that had taken 250 days to hatch. The other eggs from the same clutch had hatched almost two months (!) before it but since the egg still appeared good I did not open it. I had a lot of anxiety for sure, but I misted the egg in question heavily and waited. When the egg finally did pip (WAY later than it should have) the hatchling still had the enormous yolk sac that redfoots always have.
If I had decided a few weeks after the clutch mates had hatched, that this egg should now be opened I could very well have lost the hatchling.
In the above photograph the hatchling inside the egg is CLEARLY NOT READY TO HATCH! There are copious amounts of fluid and veining surrounding the hatchling which makes this fact obvious. When an egg is ready to hatch this material has been absorbed by the hatchling and all that remains is a large yolk sac under it.
The fact that Graham is successful in doing this is a testament to his care after the egg has been opened. But my question is this....why open an obviously fertile egg in the first place? If I have learned anything in almost thirty years of hatching tortoise eggs its this...you can never really predict exactly when they are 'ready' to pop.
If you are losing full term embryos prior to hatching then I would take a look at my incubation techniques.
Are the temps too high? Is the humidity too high? Or low? Do the eggs get jarred?
Be patient.
But if you really feel the need to open an egg, then Graham's method seems like a good one.