Shadrach's Ex Battery and Rescued chickens thread.

[NatJ]

Most production breeds have had the broodiness bred out of them. How exactly did they do that. Breeders can't even manage to get the colours right in the majority of breeding programs let alone breed out something as fundemetal to a species survival as reproduction which is what ensures the survival of the species.

How did they do that? Very simple: cull the ones that go broody most often, and incubate as many eggs as possible from the ones that go broody least often. Continue for at least a century.

I think they have done a very good job at selectively breeding chickens that do not go broody in their first year of life under the conditions that are provided to commercial chickens.

Change the conditions (like to a backyard flock) and you get a bit more broodiness, but there still are major differences between how many Leghorns or Sexlinks go broody, and how many Silkies go broody, when they all begin as chicks from a hatchery and they are all raised the same way in the same flock.

(Since commercial chickens are only kept to a certain age, I also assume the selection has less effect on broodiness at older ages.)

Evidence of effectiveness: I have a book on poultry breeding & management from 1925.
The author appears to be mostly working with Leghorns. Every broody is marked with a legband, then put in a broody breaker cage. The author says not to breed from the hens that have 3 or 4 bands by the end of the season. Leghorns? Going broody that often?!

So either something else has drastically changed and that has affected broodiness (maybe housing or feeding?), or there HAS been a major shift in the genetics of domestic chickens, by selecting strongly against broodiness.

 

[Shadrach]

How did they do that? Very simple: cull the ones that go broody most often, and incubate as many eggs as possible from the ones that go broody least often. Continue for at least a century.

I think they have done a very good job at selectively breeding chickens that do not go broody in their first year of life under the conditions that are provided to commercial chickens.

Change the conditions (like to a backyard flock) and you get a bit more broodiness, but there still are major differences between how many Leghorns or Sexlinks go broody, and how many Silkies go broody, when they all begin as chicks from a hatchery and they are all raised the same way in the same flock.

(Since commercial chickens are only kept to a certain age, I also assume the selection has less effect on broodiness at older ages.)

Evidence of effectiveness: I have a book on poultry breeding & management from 1925.
The author appears to be mostly working with Leghorns. Every broody is marked with a legband, then put in a broody breaker cage. The author says not to breed from the hens that have 3 or 4 bands by the end of the season. Leghorns? Going broody that often?!

So either something else has drastically changed and that has affected broodiness (maybe housing or feeding?), or there HAS been a major shift in the genetics of domestic chickens, by selecting strongly against broodiness.

Yeah, I've read other studies.
What if there should be evidence that the reputedly non broody breeds are kept in different conditions to other breeds?
Plenty of broody Leghorns in Italy.
I think you may have at least a partial explanation in your last paragraph.

 

[Windrider]

Once again, coming at this question as a biologist rather than a longtime chicken keeper, I doubt you can truly and completely "breed out" broodiness. That would entail actually eliminating the DNA sequences that are responsible for multiple hormones that induce broodiness and all the other genes that are responsibly for triggering them.

While I haven't researched this, I would bet that the selective breeding for less broodiness is just selecting for inhibitor genes, and all the broodiness genes are still there and can be activated if the conditions are right. The more inhibitor genes, the less likely that would be, but it could still happen. And... the inhibitor genes could be "bred" out" if the chickens went feral, since the original genes would all still be there.

 

[NatJ]

What if there should be evidence that the reputedly non broody breeds are kept in different conditions to other breeds?

I agree that different conditions could account for some of the difference.

But it would not account for the mixed-breed flocks in which some breeds go broody much more often than others, when they are all kept together in the same conditions.

 

[Ribh]

I agree that different conditions could account for some of the difference.

But it would not account for the mixed-breed flocks in which some breeds go broody much more often than others, when they are all kept together in the same conditions.

I'm not a scientist but I do have a very mixed flock of both standards & bantams. The bantams [Frizzled D'Uccles, Wyandottes & Japanese] are driving me crazy. They are constantly broody. These birds have obviously not been bred for egg production & go broody more often & for longer than my BRs, which have been bred for eggs.

 

[Shadrach]

Lets start with the statement certain production breeds are less likely to go broody than non production breeds. We can all argue about what constitutes a production breed later.

Next, I'll add my bit. I believe that the drive to reproduce is so fundamental to a species survival that it is not possible to breed it out. What is possible is to supress it.

My next proposition. Given the right environment the supression can be reversed.

Next. Chickens like I assume every other creature can make investment stratagies regarding producing progeny.

Hens can for example practice a form of contraception. I've watched hens do this. This gem of scientific discovery went down like a ton of bricks with certain ideologies as one can imagine.

https://www.livescience.com/15828-chickens-eject-sperm.html

Not a lot of point in being able to do this if the hen doesn't understand the consequences of mating to a greater or lesser extent and isn't capable of making decisions on which rooster in her mind has the genes she wants to pass on.
It gets more complex the more one learns about chicken behaviour.
For example. If a hen is kept in a single sex flock, contained in a run, has her eggs removed before she can accumulate a clutch. Lives in crowded social conditions with other hens that are not of her choosing etc etc, there may not seem much point in reproducing.
Of course what often happens is peoplle will say don't be silly chickens don't have that level of intelligence or self awareness.
I have a rather different view as do many of the people who have put some serious effort into trying to understand the chicken and carried out some rather interesting experiments and observations.

 

[Shadrach]

Once again, coming at this question as a biologist rather than a longtime chicken keeper, I doubt you can truly and completely "breed out" broodiness. That would entail actually eliminating the DNA sequences that are responsible for multiple hormones that induce broodiness and all the other genes that are responsibly for triggering them.

While I haven't researched this, I would bet that the selective breeding for less broodiness is just selecting for inhibitor genes, and all the broodiness genes are still there and can be activated if the conditions are right. The more inhibitor genes, the less likely that would be, but it could still happen. And... the inhibitor genes could be "bred" out" if the chickens went feral, since the original genes would all still be there.

Eggxactly!

 

[pennyJo1960]

This young hen is generally last to return to the coop. I've almost lost her a couple of times. The slid out ot the allotment run gate once and it was only by chance that I looked in the right direction in time to see her fluffy butt heading towards a thicket.
View attachment 2923600

The picture you posted is blank

 

[Shadrach]

The picture you posted is blank

It's just very dark Penny.

 

[NatJ]

Lets start with the statement certain production breeds are less likely to go broody than non production breeds. We can all argue about what constitutes a production breed later.
...
For example. If a hen is kept in a single sex flock, contained in a run, has her eggs removed before she can accumulate a clutch. Lives in crowded social conditions with other hens that are not of her choosing etc etc, there may not seem much point in reproducing.

So are you saying that all chickens react the same way in that all-female flock in a run, or are you saying that breed differences do exist?

Because if consistent breed differences exist, they are almost certainly based on SOMETHING genetic, no matter what mechanism we may think is involved.