Backyard Poultry Forum

I have been following a thread on the BYP Incubation Facebook page. Bob Peel has been taking us through an Incubation Workshop and the subject of hatching from round eggs came up.
I have a project pen of Marans X ISA X some others - playing with colour, type and egg colour. Most of these girls lay Round Eggs - interesting as although the egg shape is similar, there is a big variation in colour.
Now, round eggs have a habit of not hatching successfully. The suggestion was to lay them on their side for several days pre incubation and to set them air sac up, incubate and hatch upright - so - an empty incubator (or 2) and what else could I do?
So - up to 5 days 'on the bench', candled them and couldn't see an air sac, floated them and made a guess (bubble up) and set them. I'll candle in a week. Hopefully the air sac will be visible and it won't be too late to turn them over if needed

My Indian Game have always laid fairly spherical eggs but it does not seem to have had a noticeable effect on hatchability. Typical hen egg shape is said to be a biological adaption which is particularly useful for ground nesting birds to prevent the egg from rolling out of the cluster. Birds such as parrots which nest in tree hollows have almost perfectly spherical eggs.

I'd forgotten about the rolling thing until you wrote it - thanks

The next step if hatching is successful, is to cull the males from the round eggs and put the f1 hens to a male from a 'normal' egg in an attempt to set non round egg shape into the line while retaining the other traits I have chosen.

when I had my silver laced Wyandottes they produced very rounded eggs, some I even had to candle to work out which is the air sac end.

Made no difference to their hatchability, they did just fine,



Ron

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"To the Core"

Sue, was it the dark Marans egg tint that made it difficult to candle the eggs?
The reason I ask is that the makers of the Offspring sent me a sample egg tester (Candler).
It's the same design as the Lyons one from Bellsouth and very, very bright.
https://eshop.bellsouth.com.au/epages/bellsouth.sf/en_AU/?ObjectPath=/Shops/bellsouth/Products/LYC950-117
I could send it to you and see if it penetrates.

On a different topic.
Notice that I didn't raise disinfecting with 254nm UV in the Workshop, (only my machines have it).
But the fact that visible light crosses the egg when candling confirms that UV will kill pathogens in the egg lattice.

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bobpeel@greatlander.com.au

Thanks for the offer Bob. I think it was more that the air cell just wasn't well enough developed as I couldn't see it even in the lighter coloured eggs (might try putting on my glasses).
Would love to try out the candler, it looks good, but I really don't get enough dark eggs to justify it. I also need to be bit cautious with bright light - it triggers migraines for me.
The dark tint comes from a Marans/ISA cross - now need to get the colour into the right shaped egg - the round shape seems to have come from the Marans.
I don't think the UV needed to be discussed - Good hygiene is more relevant for most people.

Well the round eggs are hatching and it looks like the hatch rate will be good - how I hate the tiny viewing windows on the JN (especially when they have dander and condensation on them) I have separated the 'normal' eggs into a basket to hatch. I will band these and select a male keeper from this lot rather than a 'round' male.
Fuscipes, your comment about egg shape turned on a light in my head. If you roll what appears to be a round egg gently along a smooth flat surface it will pivot around the slightly more pointed end

A run down on the round eggs I set about 3 weeks ago
Tried to identify blunt end after laying on their side for up to 5 days too dark to candle (floating helped)
Set 41 + 8 normal shaped eggs =49 - all upright
Discarded 7 clears. At lockdown - set upright - 'normals in hatching basket.
29 Hatched from round eggs, 1 pipped at wrong end, 4 with airspace at about day 10 (on floating) 7 normals hatched and one which had externally pipped (and thought dead) is now unzipping.
So about 75 % success - with the right management it can be done.
With the dark shells, rolling would have simplified it. I will only breed using the males from the normal shaped eggs.

Thank you Sue for doing this and sharing the results.
I hear and keep feedback from numerous breeders as you might imagine.
A connection is evident with "malposition % + rolling vs rocking + round/elliptical eggs".

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bobpeel@greatlander.com.au