Shipping egg hatch rate (yes, another one)

[Tenrec]

Hi there!

I've set quite a few (~70) shipped eggs recently, and it's day 10 for one of the clutches. I typically candle at day 7, mark the ones that look dead/infertile, and then come back at day 10 to re-assess those eggs and toss any that didn't make the cut.

I now have half that clutch still in my incubator, wriggling and healthy, with a good number of the culls simply being infertile.

Now here's my issue when I'm assessing/comparing things like survivorship so far (and hatch rate later). I have seen estimates of anywhere from 30-75%, with 50% being the most common, for hatch rates with shipped eggs. Of course hatching shipped eggs is a crapshoot, and original flock/shipping conditions/distance all play a roll...But I do see the 50% figure tossed around quite a lot, to the point where I'm thinking the sample size is big enough to discount those "all-or-nothing" outliers.

To those of you who have stated these figures, are you counting infertile eggs in your hatch-rate or are you discounting infertile eggs, as we usually do with hatch rate?

In other words, are we including the normal incidence of ~80-90% fertility when we try to assess attrition in your average box of eggs, or are we accounting for it and removing it from our estimates?

Thanks!

 

[Ridgerunner]

I haven’t seen this brought up for a few years, it’s an important point. When commercial hatcheries look at fertility, they look at two different things, hatchability and incubation. Often different people work on providing the eggs than the ones hatching them in commercial operations.

Hatchability looks at the condition of the egg when it goes into the incubator and if it can even be hatched. Some people think this is only fertility but it’s much more. The nutrition and health of the parents, how dirty the eggs might be, how the eggs are handled and stored, blood spots or meat spots or excess porosity when they are candled, all make a difference as to whether or not the egg is even hatchable.

Since the people running the incubators can only control what happens after they receive the eggs, they discount all the eggs that don’t develop before they determine their portion of the hatch rate. That’s why some people think the professionals only consider the developing egg when they talk about hatch rate, the ones that run the incubators do. But the ones that provide the eggs have their own calculation on hatchability and get their bonuses or keep their jobs based on that.

To determine which way people are calculating hatch rate you’ll need to talk to the individuals. Personally I don’t put certain eggs (like dirty, cracked, or weird eggs) in the incubator or under a broody hen or in the incubator to start with. But my hatch rate is based on the number of eggs that go into incubation and how many chicks come out, though I usually distinguish between developing eggs and those that quit when I post about it. I’d guess that most people on this forum use the eggs in – chicks out method, but I know certain people that just use the developing egg method. I’m not sure I agree that your statement “as we usually do with hatch rates” is really accurate for most people on this forum. I think that is too general an assumption for such an inexperienced group that we have on here. For terminology to be consistently used people have to agree on what the terminology means.

I’m not sure your 70 eggs is a statistically significant number. The problem with shipped eggs is often how they are handled. You did not receive 70 different shipments spread out over months of different weather conditions, packed by 70 different people, and handled by 70 different people at the post office and (if they were flown on part of their journey) by airport handlers. Each individual shipment has gone through its own unique set of circumstances. Averages don’t mean anything because the sample size is so small, it’s one for that shipment. I don’t know how many different shipments you received but it wasn’t 70.

 

[Tenrec]

I haven’t seen this brought up for a few years, it’s an important point. When commercial hatcheries look at fertility, they look at two different things, hatchability and incubation. Often different people work on providing the eggs than the ones hatching them in commercial operations.

Hatchability looks at the condition of the egg when it goes into the incubator and if it can even be hatched. Some people think this is only fertility but it’s much more. The nutrition and health of the parents, how dirty the eggs might be, how the eggs are handled and stored, blood spots or meat spots or excess porosity when they are candled, all make a difference as to whether or not the egg is even hatchable.

Since the people running the incubators can only control what happens after they receive the eggs, they discount all the eggs that don’t develop before they determine their portion of the hatch rate. That’s why some people think the professionals only consider the developing egg when they talk about hatch rate, the ones that run the incubators do. But the ones that provide the eggs have their own calculation on hatchability and get their bonuses or keep their jobs based on that.

To determine which way people are calculating hatch rate you’ll need to talk to the individuals. Personally I don’t put certain eggs (like dirty, cracked, or weird eggs) in the incubator or under a broody hen or in the incubator to start with. But my hatch rate is based on the number of eggs that go into incubation and how many chicks come out, though I usually distinguish between developing eggs and those that quit when I post about it. I’d guess that most people on this forum use the eggs in – chicks out method, but I know certain people that just use the developing egg method. I’m not sure I agree that your statement “as we usually do with hatch rates” is really accurate for most people on this forum. I think that is too general an assumption for such an inexperienced group that we have on here. For terminology to be consistently used people have to agree on what the terminology means.

I’m not sure your 70 eggs is a statistically significant number. The problem with shipped eggs is often how they are handled. You did not receive 70 different shipments spread out over months of different weather conditions, packed by 70 different people, and handled by 70 different people at the post office and (if they were flown on part of their journey) by airport handlers. Each individual shipment has gone through its own unique set of circumstances. Averages don’t mean anything because the sample size is so small, it’s one for that shipment. I don’t know how many different shipments you received but it wasn’t 70.

Wow, very informative on the commercial hatcheries! Thank you for that. Have you worked in one before? Ag science always seemed much more intense than people give it credit for.

I've seen quite a few hobby breeders (like you!) who put stock in their hatch rates simply don't place eggs with visible flaws. I suppose, by not setting these eggs, they are discounting eggs that have questionable hatchability in their stats...I generally do see people here, at least, explicitly discounting infertile eggs when they speak of hatch rate.

I don't think my 70 eggs are by any means representative, because, you are right, I only have 3 shipments (and one of those was a huge dang outlier. 12/18 eggs simply didn't develop/were infertile, and many of them were fairly porous! i got six fertile eggs though, which is what i paid for...). But I almost certainly will continue incubating, so I was curious how we all compare.

As for sample size business, sorry I was vague! I meant the sample size being all the reported rates from everyone I've seen talk about shipped eggs. It's by no means a formal study, no, and I didn't actually crunch numbers. : p

It'd be awfully nice if we could actually glean comparable data for a more formal study. We'd certainly have a good /potential/ sample size, barring the issues of coordination and human error.

 

[Kiki]

I have no advice..but I think you might be interested in this thread:
https://www.backyardchickens.com/t/1155066/it-occurred-to-me-crazy-egg-idea/70#post_18349141