Sustainable breeding with small numbers?

[triplepurpose]

I am doing it with American Dominiques and American Games.

My situation closer to yours more than you know. I have Voter strain American Dominiques that are a closed flock. Now eight years into selective effort with them. A parallel effort involves development of Missouri Dominiques that are bred to be more like pre-civil war American Dominiques. To achieve that end I started with Cackle Hatchery American Doms in 2009 and infused American Game into them which greatly increase genetic variation I could work with. A little Voter strain to be used later. With exception of one white-legged game rooster, the Missouri Dominique effort has been closed with no replacements coming from outside in the eight years since project started.

Centrarchid, your breeding work sounds fascinating! Do you have an pics anywhere of your breeders? I'd just be curious to see what you've accomplished with those dom strains...

 

[lazy gardener]

Quote: I had toyed with the idea of moving in that direction. From my understanding, you can produce auto sexing birds in 3 generations by back crossing in a certain way. If you're interested in pursuing that, you can find the needed breeding information by doing some google searches. I've been delighted with the BSL's produced with EE x Dom crosses, and my customers love picking up my older BSL hens. At this point, I'm simply pleased to be producing my own barn yard mixes. Am bringing in some new blood this spring, including Doms, EE, PBR, BE, SLW, Columbian Wyandottes. If they are all good birds, I'll have a very hard time doing my fall cull.

 

[triplepurpose]

I have researched it a little--the auto sexing breed creation that is. I found this site that suggests using any wild-type color pattern breed (with the chipmunk pattern chicks, which they claim provides the best background for color sexing chicks). According to them, one just crosses like so: non-barred male to barred female, barred F1 males back to non-barred females, barred F2 males and females to eachother, after which it seems like it would basically just involve culling anything that isnt what you are after (ie pure barred birds that clearly show sex at hatch). Sounds intriguingly straightforward... and how convenient that the first step just happens to be breeding BSLs!

I've been reading up a lot about chicken genetics recently and its fascinating!

Thats nice to hear youve been happy with your BSLs. I wonder about the eggshell colors, since I dont know if our rooster has only one or both copies of the blue egg gene, and one of his hatchmates lays grayish eggs rather than true blue. Could be fun to find out!

Thanks for the info!

 

[Beekissed]

Quote:
If this is your only goal, why worry so very much about inbreeding? Inbreeding of chickens is not quite the disaster it is with other species of animals and, from what I understand, it can be done for a good long while without any ill effects to the flock. Think of landrace breeds and other flocks/breeds that didn't get any new influx of genetics for generations upon generations and it didn't cause problems...it actually made for a stronger, better flock.

Why not just keep a couple of males, a large group of females and do flock breeding, culling the worst, breeding the best in laying performance and other desired traits each year? I'd venture to say you could go on like that for a long time and still attain the simple goals you have.

 

[lazy gardener]

Quote:

If this is your only goal, why worry so very much about inbreeding? Inbreeding of chickens is not quite the disaster it is with other species of animals and, from what I understand, it can be done for a good long while without any ill effects to the flock. Think of landrace breeds and other flocks/breeds that didn't get any new influx of genetics for generations upon generations and it didn't cause problems...it actually made for a stronger, better flock.

Why not just keep a couple of males, a large group of females and do flock breeding, culling the worst, breeding the best in laying performance and other desired traits each year? I'd venture to say you could go on like that for a long time and still attain the simple goals you have.

And this simplistic approach is exactly what I'm doing, with the exception that I simply can't resist bringing in new chicks now and then. Love the eye candy, and looking forward to seeing how their gene pools mingle with my existing gene pool.

 

[triplepurpose]

If this is your only goal, why worry so very much about inbreeding?  Inbreeding of chickens is not quite the disaster it is with other species of animals and, from what I understand, it can be done for a good long while without any ill effects to the flock.  Think of landrace breeds and other flocks/breeds that didn't get any new influx of genetics for generations upon generations and it didn't cause problems...it actually made for a stronger, better flock. 

Why not just keep a couple of males, a large group of females and do flock breeding, culling the worst, breeding the best in laying performance and other desired traits each year?  I'd venture to say you could go on like that for a long time and still attain the simple goals you have. 

I guess "large" is very subjective, but we dont really want/need/or can afford to feed what I at least would a consider a "large flock of hens"-- unless you consider 12-18 max "large." Doesn't this seem a bit small for such flock breeding to be sustainable? Or...would it actually not be so? After the first generation with only two cocks mating (with one usually dominant and breeding more I would project) at least half of all subsequent matings would be half siblings and because of the small number of chosen breeding hens, many full. Please forgive my skepticism that this just doesnt seem very sustainable---but...by all means please set me straight if my notions are indeed mistaken...?!

 

[Ridgerunner]

A very common model used on farms for thousands of years was to keep breeding your own replacement roosters and hens, then bring in a new rooster every four or five generations to bring in new blood. I grew up on one of those farms many decades back. When Dad decided he needed a new rooster with outside blood he’d go to the co-op and bring home a dozen straight run chicks. He’d keep a rooster from to be the new flock master and we’d eat the old one. And he’d keep some of the hens. Dad’s normal winter flock size was one rooster and about 25 hens.

Before there were co-ops and feed stores with chicks, farmers would swap roosters whenever they felt they needed to. It was a very common model. I still do it that way.

 

[triplepurpose]

A very common model used on farms for thousands of years was to keep breeding your own replacement roosters and hens, then bring in a new rooster every four or five generations to bring in new blood. I grew up on one of those farms many decades back. When Dad decided he needed a new rooster with outside blood he’d go to the co-op and bring home a dozen straight run chicks. He’d keep a rooster from to be the new flock master and we’d eat the old one. And he’d keep some of the hens. Dad’s normal winter flock size was one rooster and about 25 hens.

Before there were co-ops and feed stores with chicks, farmers would swap roosters whenever they felt they needed to. It was a very common model. I still do it that way.

That was kind of my understanding of traditional husbandry, and similar to what we've done in the past too. But their are no sources that sell straight run dominique chicks locally (or any SR chicks), no other farmers I know of locally keeping them, and I'm not crazy about the whole mail order hatchery thing (tho obviously we will stoop to buying straight run in the mail when we must).

I have great reverence for and admiration for traditional methods and often prefer them. I guess Im just hoping to find a way to preserve vigour a bit longer than 4 or 5 generations without absolutely NEEDING to bring in new hatchery blood, while balancing convenience and having a productive laying flock (with some room to modestly improve stock if possible).

BTW, anyone know why you don't hear more about clan mating with only two clans? Why should three be the minimum? Two seems like it would be easier to manage, and you could breed one clan per season, mating hens at two years or older (giving you time to asses laying abilities and other traits), but direct inbreeding would be minimal.

I wonder, what might the advantages or disadvantages be with this compared to the "rolling matings" aka "old farmer method" of dividing flock in two and mating young to old/old to young? It seems like the former may guarantee less inbreeding, but the latter perhaps allows for more shuffling and combination of genetics and selections for each generation from a wider pool of (albeit sometimes more closely related) offspring...? Since in the OFM offspring from both groups effectively form their own new clan each season (while the rest are subsumed into the old group or culled)....

But again, if two clan systems could work, why do most sources suggest at least three? I imagine to some degree it comes down to what your selection criteria are as well...

Oy, I have so much still to learn... and sometimes I do tend to overthink things...

 

[Ridgerunner]

When you are breeding to improve the flock, to breed show birds, to create a new breed, or to improve your strain, you are limiting genetic diversity in the traits you want to limit them. If you are trying to breed a flock that lays a certain shade of brown egg, lays a larger egg, or has a specific eye color, you want to limit the genetic diversity of those genes that give you anything other than what you want. That is selective breeding. But you don’t want to limit the genetic diversity responsible for health and vitality. You want to keep that as varied as you can.

By using a three clan rotation instead of two clans, you maintain more of that diversity. A four clan system would work even better, but people have found that three works really well.

You may have played with that color/pattern calculator. When you cross two different color/pattern purebred birds, you can be pretty sure of what you will get because of dominant/recessive genes. But if you then cross the offspring of that first cross, you get a huge variety of possibilities. That shows how diverse those genetics are. But if you take it the next step and cross the offspring of two of those crosses, even if they look a lot differences, the possibility of the appearance of their offspring really drops. By selecting two specific birds to cross, you have limited yourself to the genes they actually carry, not what genes they could potentially carry.

I probably haven’t explained it very well, but playing with that calculator made it real plain to me just how much genetic diversity you lose with each round of inbreeding. But by using a three clan system instead of a two clan, you greatly limit how much you actually lose. Good breeders can keep a flock really doing well for many generations with that spiral breeding system.

 

[triplepurpose]

That makes sense! Thank you.

Just found this article, however, where the author describes how they use "family matings" which is basically two-clan spiral breeding. What do you all think of this approach?

3 clan sounds sweet, Im just doubting now if we would really have the numbers to make it work or how necessary it is... I mean, what is the functional minimum number of pullets/hens a clan can have to still make the system work? And Im reluctant to deal with lots of roosters if I really dont have too--i would like the whole flock to be able to live together except during breeding--requiring a separate rooster pen/tractor in this case is less than ideal, and something to undertake only if we decide its absolutely necessary.

As with most things i guess, its about finding a functional balance that works fir us. Fortunateky, we still have some time to figure things out and do our homework..,