Egg Size Body Traits

[SourRoses]

I wanted to ask about evaluating pullets for potential egg size, and the traits that will lead to larger eggs in subsequent generations.

On scouring the internet, I found a few references to such traits. I simply haven't been able to verify or get more information, so I am hoping for more experienced folks to chime in.

- Thinner Legs are supposed to be indicative of the overall skeletal structure including the pelvis, and a thinner pelvis is supposed to provide a wider opening allowing for larger eggs.
- Overall body size.
- Measurement of the pelvic points on laying hens with a goal of at least two fingers across and four fingers vertically.

What other traits do you know of that are associated with bigger eggs?

It's one of my main breeding goals to have XL eggs from first year hens.
I'd really like to learn more and develop a concrete plan towards that goal which is a little more nuanced than "hatch big eggs".

 

[Amer]

I haven’t heard of the thinner skeleton, but it could be right. I believe that 4 fingers wide between the pelvic points is ideal, along with a deep heart girth and a broad back which allows room for all of the organs. I have narrow fingers but even on some bantams I could fit at least three between the pelvic bones.
They have to be laying before you can judge that kind of thing. Also, the pelvic bones should be prominent. If the bird is fat enough that you can’t feel them easily she might not be allocating her nutrients into egg laying (plus a fat bird has more issues laying.)

 

[Amer]

And of course the larger the bird the larger the eggs will be, but the egg size to body ratio goes down.

 

[DarJones]

There are several factors including the genetics and the size of the chicken. I'm working with Silver Laced Wyandotte genetics crossed to blue egg laying Brown Leghorns. The leghorns bring traits for large eggs into the mix. The Wyandottes bring a large deep body but with lower total egg production. My selection effort is focused on retaining Wyandotte body size which is larger than Brown Leghorn and on total yearly egg count. I've found that a few of the hens consistently lay jumbo eggs.

I have a single hen that lays 70 gram eggs. This is the size range of an average turkey egg. The other hens weigh less down to about 45 grams as the smallest egg produced. You can evaluate body traits until you are blue in the face, but in the end you will have to weigh eggs and save only the largest. Get a really good kitchen scale and look for eggs over 65 grams.

Traits:
1. Jumbo eggs
2. Yearly egg count laid per hen
3. Consistency of laying - where a hen that lays 9 days out of 10 is a very good hen.

 

[FunClucks]

I wanted to ask about evaluating pullets for potential egg size, and the traits that will lead to larger eggs in subsequent generations.

On scouring the internet, I found a few references to such traits. I simply haven't been able to verify or get more information, so I am hoping for more experienced folks to chime in.

- Thinner Legs are supposed to be indicative of the overall skeletal structure including the pelvis, and a thinner pelvis is supposed to provide a wider opening allowing for larger eggs.
- Overall body size.
- Measurement of the pelvic points on laying hens with a goal of at least two fingers across and four fingers vertically.

What other traits do you know of that are associated with bigger eggs?

It's one of my main breeding goals to have XL eggs from first year hens.
I'd really like to learn more and develop a concrete plan towards that goal which is a little more nuanced than "hatch big eggs".

If you feed them higher protein in their commercial chick starter, they will lay larger eggs. I ran across a couple state cooperative extension office publications that mentioned this, and I know of at least one breeder that increased her egg size something like 30% over the parent egg size by feeding more protein than is typically recommended. I think she was feeding 23% (?) protein chick starter. So there is a connection between diet for the first 19-20 weeks and size of eggs produced.

I have some ISA brown that lay large - extra-large eggs, and a few prairie bluebells that lay large eggs. They are drastically different in weight/size - the PBBs are maybe 3-4 lbs and have awesome feed to egg conversion. I think it depends on what they're bred to do as much as the quality of their nutrition. If you want extra-large eggs straight out the gate, get ahold of some commercial production hens, they typically are bred for that size of egg. Breeding lineage matters even then. I'd love to have some commercial hens that lay extra-large every day, but I'm not sure if they're available in the non-commercial market.

 

[nicalandia]

Look at Leghorn's pelvic bone and try to breed for that.