Hen ONLY lays double yolk eggs

[TundraFang]

One of my hens has been laying for a few weeks and she only lays double yolk eggs. She's never laid a 'normal' egg since she started laying. I thought it was just because she's a new layer but it's been going on for a while now. Is this normal? Will she start to lay regular eggs as she matures?

 

[Birdie2019]

One of my hens has been laying for a few weeks and she only lays double yolk eggs. She's never laid a 'normal' egg since she started laying. I thought it was just because she's a new layer but it's been going on for a while now. Is this normal? Will she start to lay regular eggs as she matures?

I’ve heard it happen a few times before with different hens, so it is possible. But it may or may not continue. Some hens only lay double yolkers.

 

[TundraFang]

I’ve heard it happen a few times before with different hens, so it is possible. But it may or may not continue. Some hens only lay double yolkers.

Do you know if it's genetic? I was hoping to breed her but I wouldn't want to go through the hassle of hatching twins if I'm going to end up with another hen that only lays doubles

 

[aart]

but I wouldn't want to go through the hassle of hatching twins

Don't even bother.
What breed is she?

 

[NatJ]

Do you know if it's genetic? I was hoping to breed her but I wouldn't want to go through the hassle of hatching twins if I'm going to end up with another hen that only lays doubles

Yes, it is probably genetic. I know the tendency to have different numbers of babies at a time can be inherited in mammals (litter size in pigs or dogs or rabbits, singles vs. twins or multiples in sheep, and so forth.)

I would not try to hatch any of the double yolk eggs. I think it would be more bother than it is worth.

If she later switches to laying normal eggs, the normal ones should hatch just fine. But you would want to think about how long she laid double yolkers, and how much it would bother you if her daughters or granddaughters did the same, before you decide for sure about hatching her eggs or not.

 

[TundraFang]

Don't even bother.
What breed is she?

She's a Cornish X

 

[Ridgerunner]

She's a Cornish X

Interesting and surprising. The mothers and grandmothers of Cornish X lay hatchable single-yolked eggs so it's not something bred into Cornish X. I really expected you to say she was one of those commercial hybrid egg layers that are bred for enhanced laying. But each individual hen is unique.

A hen can release two yolks in the same day. She's not supposed to but it happens. There are certain triggers that tell her to release a yolk to start the internal egg making journey through her egg making factory. If two yolks are released at the same time you can get a double yolked egg. If they are separated by a little time she might lay two eggs in the same day. Often one has a very thin shell as she does not have enough shell material for two eggs so it may not be hatchable.

I consider a double yolked egg a deformity. They don't fit in an egg carton. They are too big to be used in baking recipes. The larger size makes them a little more susceptible to egg laying issues. And they are difficult to hatch. There are some threads on here where somebody was able to get one or even two chicks from a double yolked egg but those successes usually take a lot of hands on and still often end sadly. As interesting as they are I'm not thrilled when I see a double yolked egg.

Some hens are more prone to laying double yolked eggs. It's possible it could be genetic, it may be that she was just put together wrong or her instincts that trigger the release of the egg yolks to start the egg making process are just off. That might be genetic or it might just be a glitch, something like a random birth defect. Pullets just starting to lay are more prone to egg laying mishaps of all kinds, including double yolks. Often they straighten out over time and debug their egg laying system. Your CX might or might not. One trigger that can cause them to release extra yolks is they they are eating really well, they have an excess of nutrients. I don't know if you are restricting her diet for health and longevity reasons or not.

I'm not sure what kind of breeding program you plan or what other options you have. If her eggs straighten out you can try to hatch them, single yolked eggs should hatch fine. I don't know how likely it is to be genetic. But if I had other options I personally would not use her.

 

[TundraFang]

Your CX might or might not. One trigger that can cause them to release extra yolks is they they are eating really well, they have an excess of nutrients. I don't know if you are restricting her diet for health and longevity reasons or not.

She's 100% free-range so I'm not sure what she's eating other than the occasion treats I give her. Maybe I'll feed her layer feed for a bit and see if that makes a difference

I'm not sure what kind of breeding program you plan or what other options you have. If her eggs straighten out you can try to hatch them, single yolked eggs should hatch fine. I don't know how likely it is to be genetic. But if I had other options I personally would not use her.

I was hoping to breed her to start raising meat chickens. I originally planned to eat her but I got attached so now she lives with my layer flock. Her sister lays normal eggs so I'll use her to start my breeding line instead

 

[Ridgerunner]

If she is free ranging you are not overfeeding her. You can always try a change of feed, you never now what will help. By free ranging her and letting her find her own food you are limiting her eating which has probably contributed to her and the other one staying alive and healthy this long.

I should have mentioned that the only time a double yolk egg laying chicken is a problem for me is when it is a regular occurrence. As far as I'm concerned any of us, including pullets or hens, are entitled to an occasional oops. It's when it becomes regular that it becomes a problem.

 

[NatJ]

One of my hens has been laying for a few weeks and she only lays double yolk eggs. She's never laid a 'normal' egg since she started laying.

Just to be sure: you have cracked the eggs open and seen two yolks, right?

Because Cornish Cross are rather known for laying big eggs, so if you are judging purely from the size of the egg you might want to check.