Line breeding: how do I get started?

[gjensen]

Hum, some folk on BYC don't even get genetic shorthand, . I have studied epigenetics. A fascinating arena of thought.
I have a collie breeder friend who has used it extensively for health in her private life and in her collie breeding program
with astonishing positive results. That said, these were mammals, not avian. It's a whole different thing. Tesio, Bohannon,
and others have addressed epigenetics in mammals when they didn't even know what it was. Even when one is discussing
animals , the subjects of changes in microsatellites and the effects of epigenesis on the major histocompatabiity complex (MHC)
are way beyond anything the average breeder needs to succeed. For most of us, "the art of breeding" plus a dash of
genetics is all we need to succeed. Fun Fact: goldfish use their sense of smell to select spouses who will produce most productive
MHC in their young.
Best Regards,
Karen

Karen, to be frank, epigenetics is irrelevant concerning this discussion. It sounds good, but that is all. If we start with good genetics, make good breeding decisions, and have good management practices, we will move forward. Anything else is a distraction. We try to make it more than what it is. New people have a greater tendency to get caught up in these things than anyone else.

 

[Yoyo with chick]

 
Hum, some folk on BYC don't even get genetic shorthand, . I have studied epigenetics. A fascinating arena of thought.
I have a collie breeder friend who has used it extensively for health  in her private life and in her collie breeding program
with astonishing positive results. That said, these were mammals, not avian. It's a whole different thing. Tesio, Bohannon,
and others have addressed epigenetics in mammals when they didn't even know what it was. Even when one is discussing
animals , the subjects of changes in microsatellites and the effects of epigenesis on the major histocompatabiity complex (MHC)
are way beyond anything the average breeder needs to succeed. For most of us, "the art of breeding" plus a dash of
genetics is all we need to succeed. Fun Fact: goldfish use their sense of smell to select spouses who will produce most productive
 MHC in their young.
Best Regards,
 Karen

 Karen, to be frank, epigenetics is irrelevant concerning this discussion. It sounds good, but that is all. If we start with good genetics, make good breeding decisions, and have good management practices, we will move forward. Anything else is a distraction. We try to make it more than what it is. New people have a greater tendency to get caught up in these things than anyone else.

However I think that once you become more expirienced then you can start learning these other terms...

 

[3riverschick]

Karen, to be frank, epigenetics is irrelevant concerning this discussion. It sounds good, but that is all. If we start with good genetics, make good breeding decisions, and have good management practices, we will move forward. Anything else is a distraction. We try to make it more than what it is. New people have a greater tendency to get caught up in these things than anyone else.

Hi

I'm not disagreeing with you, George. I thought I was agreeing with you. I was trying to make the point
that with epigenetics being so "out there", it really was of no use to other than to the large commercial
breeder like Hy-line.
Best,
Karen

 

[3riverschick]

However I think that once you become more expirienced then you can start learning these other terms...

You could distract yourself with it for curiosities sake if you were bored, however it really has no value to us.
Best,
Karen

 

[tridentk9]

Hum, some folk on BYC don't even get genetic shorthand, .

IME- If you treat people like they can't learn, they won't. Isn't epigenetics behind sex determination in some reptiles, ie alligators. Though the result isn't inherited as the next generation goes through the same on/off switch for sex. Pottinger's cats could be a case of epigenetics, though I've always wondered about the pot more than the food.

Chooks4life said her offspring from youngsters weren't as good as their full siblings when their sire/dam were older. Given the same flock, same caregiver, same diet, etc- yeah, epigenetics could be a reason for the difference. Anecdotal but a theory has to start somewhere.

 

[gjensen]

Hi

I'm not disagreeing with you, George. I thought I was agreeing with you. I was trying to make the point
that with epigenetics being so "out there", it really was of no use to other than to the large commercial
breeder like Hy-line.
Best,
Karen

No, we are on the same page. I doubt it is even a concern of Hy-line. If it is, it is a minor consideration. I believe it's relevance in poultry breeding is being overstated. A faddish philosophy that is more related to a sense of idealism than it is sound breeding practices.
Sound breeding practices are based a few key fundamentals. Good genetics, good decisions, and good management. That is all. It is not anymore complicated than that. I have never heard anyone that had any LONG TERM VERIFIABLE SUCCESS with any breed of poultry concern themselves with these ideas. Not one. I am not referring to a backyard scientist. Walk the aisles of the Nationals, and let me know how many serious conversations that you will be able to maintain. I suspect that you will get some odd looks.
So no, we are in agreement.

 

[gjensen]

IME- If you treat people like they can't learn, they won't. Isn't epigenetics behind sex determination in some reptiles, ie alligators. Though the result isn't inherited as the next generation goes through the same on/off switch for sex. Pottinger's cats could be a case of epigenetics, though I've always wondered about the pot more than the food.

Chooks4life said her offspring from youngsters weren't as good as their full siblings when their sire/dam were older. Given the same flock, same caregiver, same diet, etc- yeah, epigenetics could be a reason for the difference. Anecdotal but a theory has to start somewhere.

Epigenetics is real, but of no practical use for the poultry breeder. An amateur should first master the art of poultry breeding, and then concern themselves with other fanciful ideas. And I certainly would not take lessons from internet authorities on this subject. This science is in it's infancy, poorly understood, mostly theories, and rarely with any real consensus. These ideas have been bounced around since the 40s, and is only now, gaining any traction.

This was a line breeding thread, in a forum for breeding poultry to a Standard. I am not saying that the topic is of no interest. I am saying it is not relevant to this cause.

What the hobby needs is more talented breeders, and less talented talkers. Of all the new interest in poultry, there are only a few sincerely interested in learning the craft.

 

[chooks4life]

You are correct. Epigenetics is a very complex and poorly understood subject. With that in mind, I would be cautious about attributing anything I see to it.

That field is not understood well enough for layman to feel like they understand it either. Much of it has no real consensus, and it's effects have been long debated. Certainly there is evidence of it's influence, but if the experts do not understand it, I would be cautious about it. Also it is more about cell development, than it is about the actual DNA chain. We are not talking about mutations. Then it is often not heritable, though occasionally it is. In the wild, it is more often seen in plants than it is in animals.

We are a long ways off from understanding it, and much of what we see now is speculation and chatter. What we hold as truth today, may be different tomorrow. I agree that it is an interesting topic, but if the experts are still debating it or do not have a grip on it, I certainly will not go there. I do not like throwing around names and subjects that I do not fully understand. Especially when it is poorly understood by the experts. I do like that it receiving more attention by the experts.

What we do agree on is good health, vigor, feed, water, and environment. To me that is good husbandry, and common sense. I do not need anything to explain it's importance. That is clear and easily understood. We also agree that the bird should be mature enough to produce viable offspring. For a pullet, that is when her eggs have reached a reasonable size and she has laid for a time. At that point, her offspring will be as viable as they ever will be. Her eggs will not be the size they will ultimately reach, and therefore the chicks will nor be as large. Those chicks, all else being equal (and good management), will reach their genetic potential. By the time the feather out, the averages are similar.

I will use the article above as an example that is easy to reference. The writer of that article describes using pullets as part of that breeding plan. The writer of that article has bred ore birds than all of us put together. I assure that if he had experience tat was contrary would be aware, and would not recommend a breeding plan that used pullets.

I realize that I am not going to convince you, and that is fine. It has been a interesting discussion anyways.

I do prefer breeding hens, but it is for a ore complete evaluation. Not because mature pullets cannot produce viable offspring.

Overall I agree on most points there, not all, but it appears that you have misunderstood and thought I was attributing the whole discrepancy to epigenetics... I wasn't. I know they're hugely influential but I'm still not sure why I see the results I do, but it's one of the likeliest potential explanations from my research on the subject and I do believe they are most likely involved in this as well.

At no stage did I claim that I understood epigenetics comprehensively or even thoroughly, so some of the comments in response to that one word I wrote are rather strange...

However I do know that for thousands of years animal breeders and farmers all over the world noted the very same thing as I have seen. Regardless of anyone who in recent years has bred many generations building from the work our ancestors established in domestic breeds, I know what I see among mine and other peoples', and that's poorer quality offspring from underage parents, which incidentally was something the majority of original developers of the breeds held to be an almost universal truth. Not all did, and just because the majority believed it didn't mean it was inherently true of course, but my experiences support that old bit of lore's validity.

I don't put any real stock in the figures of any one individual's breeding program output unless they're measuring much, much more than just 'animals bred' or 'percentage of animals in good health, fertile, bred to S.O.P.' or 'producing X amount of eggs per year' or whatever. This is not to attempt to offend you nor them, nor to dismiss skill, knowledge, or results, just that in my experience there are many breeders out there who are a success in their own estimation and/or the common public's perception (not without good reason in most cases) yet to others their results are not ideal outcomes. Different beliefs of course are what is behind one mans' trash being another mans' treasure. It's the same with animals.

I think it's interesting and relevant that historically the "underage parent = poorer grade offspring" belief was held to be a truth and the animals we have now are in large part due to that belief being influential. I'm pretty sure that the animal breeders who originally helped shape raw domestic animal species into definite and refined breeds would have noticed if there was no negative result to breeding underage parents, yet it was considered a fact; not due to superstition, either. More than we modern farmers/breeders, they had incentive to hastily produce all the offspring they safely could. They may have lacked genetic science but they didn't lack a keen eye and despite their lack of formal education equivalent to modern certification standards, there were many breeders par excellence among our ancestors.

Only recently due to modern industrialized agriculture has there been a shift onto breeding females as young as possible, and having emphasis on that capacity, which in fact used to be selected against among some domestic species, so breeding programs have shifted to accommodate the market demand. Most commercial cattle producers in Australia cull all females not pregnant before they're a year old, no matter the reason, and we have the same demands in place on sheep, goats poultry, and so forth. I know it's not too logical to compare an egg to a mammalian fetus, but that kind of thinking led me to breed my chooks young and expect their offspring were about as good as they would ever be. Only years after beginning breeding did I give that up, based on comparison of the results. They were good enough, but later breedings made better.

But people grade their animals very differently, where one sees a defect or weakness many others see total health. We all have different aims too which skews our criteria for 'good' vs 'bad' poultry.

I'm not trying to convince you either, merely providing my reasons for believing what I do in this area. I'm also not trying to insinuate that all your chooks are poor grade, nor make any such inference about any other persons' chooks just because they breed young parents. As I said they can still be good by normal standards, but I see better results in later clutches.

The people who developed domestic animals all over the world for the most part considered it very unwise to breed overly young parents but specifically females, and they preferred to wait until they were in prime age before breeding, especially when breeding for 'keeps' of future breeders. That's across all domestic species and that includes chickens. That historical background, combined with my experiences across many species showing the same results, is more relevant to me than the never-ending arguments of academics on the 'why' or even 'if' behind the results --- I don't doubt you'd occasionally get good offspring from younger parents but I don't bother with it as it is so often a false economy. They only look good until compared to later results, in my experience and many others', but, with that said, it's still possible there are some bloodlines which produce better offspring young, in fact I suspect that's what we're now selecting for in Australian livestock. However I don't believe they're the majority, if they even exist at all. But that's just my opinion.

Hum, some folk on BYC don't even get genetic shorthand, . I have studied epigenetics. A fascinating arena of thought.
I have a collie breeder friend who has used it extensively for health in her private life and in her collie breeding program
with astonishing positive results. That said, these were mammals, not avian. It's a whole different thing. Tesio, Bohannon,
and others have addressed epigenetics in mammals when they didn't even know what it was. Even when one is discussing
animals , the subjects of changes in microsatellites and the effects of epigenesis on the major histocompatabiity complex (MHC)
are way beyond anything the average breeder needs to succeed. For most of us, "the art of breeding" plus a dash of
genetics is all we need to succeed. Fun Fact: goldfish use their sense of smell to select spouses who will produce most productive
MHC in their young.
Best Regards,
Karen

It is more complex by far than what the average breeder needs to succeed, I agree wholeheartedly, I think it's only going to be relevant to those with more of an interest in genetic disease until such a time as it's better understood and the information has been disseminated into the general public in terms everyone can understand and use.

At no point am I claiming any in-depth knowledge of epigenetics but my learning on chickens in general leads me to believe that's the most likely cause of much of what we're seeing.

As for the back and forth on the subject and the lack of general agreement among scientists, that's true for almost all subjects to some extent and when something holds true in your experience you'd have to be a bit daft to dismiss it without question just because one researcher comes out with a study purporting to show it's false; I've read some BS whoppers from experts, doctors, scientists etc which were 'known' to be 'true' before being discovered to be wrong; indeed some are still considered to be true.

You probably know the saying, 'you can find studies proving or disproving anything, from all sorts of reputable sources'.

When I mentioned epigenetics I had in mind some studies I'd read on avians and the differences in their offspring when bred from very young parents, or when the environment or diet has been changed somewhat... The differences aren't able to be simply explained but there are discrepancies observed more often than not when comparing offspring from very young parents against offspring from the same parents when older and the bias is against overly young parents. But the same bias is observed in many species. I've observed it firsthand in my own animals, and in those of people I know.

I'd be a bit more cautious personally in dismissing anything based on 'avians compared to other species' --- not that I am accusing you of doing that, but this subject tends to come up every now and then, and some very knowledgeable people can't see the forest for the trees because they automatically dismiss any correlations between avians and mammals or whatever.

There are great differences for sure but there are similarities throughout the natural world from plants to birds to mammals and so forth.

Recently I had a bizarre conversation with a well-read member of this forum on nutrition. I mentioned that some artificial fertilizers have been proven, for decades now, to prevent uptake of, or usage of, some vital nutrients by up to 100% when the pastures are grazed by animals after being topdressed too often. (The original discussion was on poultry showing unreasonable malnutrition despite their diet so I ended up mentioning that agricultural issue, because some plants do not contain proper nutrients due to the way the soils' been treated as it then binds nutrients.)

He dismissed that out of hand, saying 'when you compare the digestive system of an avian to a mammal, you've lost me' --- but at no point did I do that, what I stated was that the plants themselves, the soils themselves, were no longer functioning as they naturally do because the nutrients were 'locked'.

Doesn't matter what species' digestive system the plant is going through when the nutrients have not moved from the soil into the plants in the first place!

Random anecdote there but some people too quickly close their minds to similarities no matter how reasonable just because 'avians compared to mammals' --- that seems to crop up somewhat too often and not under the correct context. (I'm not saying you've done that here, it's just something that's been percolating in my mind concerning the too often dismissed similarities or common ground.)

Best wishes.
Quote: Karen, to be frank, epigenetics is irrelevant concerning this discussion. It sounds good, but that is all. If we start with good genetics, make good breeding decisions, and have good management practices, we will move forward. Anything else is a distraction. We try to make it more than what it is. New people have a greater tendency to get caught up in these things than anyone else.

In order to be able to authoritatively state that epigenetics are irrelevant in this discussion you'd need to be quite the expert on the subject, though, wouldn't you?

With all due respect, in answer to your latter statement here, I'd like to re-quote your earlier statement on epigenetics, which I agree with:

Quote:

Such a statement, which does seem spot-on to me, also precludes the validity of any statement outright dismissing epigenetics or their potential involvement in the topic under discussion.

Best wishes to all.

 

[gjensen]

Chickens grow and mature sexually faster than most livestock. Certainly when a pullet first begins to lay it would not be smart to set those eggs. Given some time to fill out, and get the egg size up, she is a good producer. I think in that sense we agree and disagree. We are not discussing a 6 month female dog. Even then, is this epigenetics or whether or not she has matured physically enough to perform the function well? Certainly in this example, this would be bad for the female and her pups. I think what I would call it is irresponsible poor management. To me, it does not need a fancy name.

Your comments on plants, fertilizers, etc. are certainly relevant. Plants certainly "feel the effects", and show the effects of chemical influences. I do not know many that would argue that how that field is treated is directly correlated to how that field performs. How the field performs directly affects the livestock that depend on it.
And this brings me to my stand on the topic. We are discussing DNA, but this discussion involves how an outside influence influences cell development. That is what epigenetics is. How an outside influence affects cell development.

Under the topic heading of line breeding, it is a little out of place. Inheritance (DNA), relationships, breeder management, breeding plan etc.

Most of us need to learn the basics of breeding poultry. When you develop a world class line of such and such, please share how epigenetics helped you get there. I will be the first to take notes. I am eager to learn how to better advance what I am working with.

Again, I agree it is a interesting topic, just an unrelated topic.

 

[tridentk9]

Sigh, management has a lot to do with epigenetics. Diet and environment are key to those on/off switches.

Don't you worry about bottlenecks and a lack of diversity using the posted breeding plan? I realize the plan posted was the quick version but what do you do if your ten best are all siblings? How do you deal with the complete loss of some potentially valuable genes? Lowered MHC? It has to be important in poultry too.

FYI- I have no plans for poultry breeding. Not interested. Plus no roosters, no breeding. Common problem I'm sure. Worked with parrot breeders. Not sure why you can have Cockatoos and Macaws yet not roosters, I think my hearing is permanently affected. Raising chickens is a piece of cake compared to them.

This could have been a discussion about a multitude of species in almost any time in history. It's both funny and sad. I am sorry that some poultry breeders feel an us/them mentality. It only lessens your chances of learning.