Starting a pure breed flock?

[Lewis77]

I have a question about starting a new pure breed flock. I want to start breeding quality pure breed Jersey Giants. So far I have 12 chicks coming from a great line. My question is should I get some more chicks from another line and cross the two lines to get started? Or just use the one blood line? I am worried about the chicks being to close in relation like brother /sister.

 

[Ridgerunner]

If I were you I’d look up spiral breeding. It’s probably how those were managed. It’s a way to help maintain genetic diversity, at least to a point, without bringing in new blood. One a show quality strain is developed it’s probably the most common method to manage them.

There are several fine points and some variations so I really do suggest you do some study, but the general idea is to establish three flocks. The females always stay in the same flock, the males rotate each generation through the flocks in a specific rotation. They only need to be separated during breeding season. Good record keeping and marking is essential. Some people may rotate females instead of males. It has the same effect.

 

[centrarchid]

The effort will be long-term. Start thinking ahead about keeping backup roosters in a bachlor group and hens in more than one group in addition to reasoning provided above in the event predator management fails. I split each line into two groups. Lines can then be comingled so long as they are properly marked.

I keep most groups in 10 x 10 dog kennels although some hens are kept in their own pens by themselves.

 

[aart]

Hmmm....I've been wondering about this.
When starting, especially with chicks of hatching eggs, wouldn't you want to be sure those birds were of totally different parentage so as to not ever cross siblings?
I would think this would be very difficult. So many folks don't keep them separate, and anyone can say they are a 'breeder' with such and such lines.
Maybe I'm just terminally skeptical.

 

[centrarchid]

Sometimes crossing even full-siblings is OK. Like with products of other matings you must scrutenize them carefully before making those products into breeders. Same can be said when you outcross. Least concern is when you get to the point of line-breeding where you keep breeding back to a quality ancestor and even then..................

 

[Ridgerunner]

Aart, I’m sure you know that every chicken breed was developed by inbreeding. Every championship show chicken was developed by inbreeding. Every championship line is maintained by inbreeding.

Genetic diversity is the issue, of course. For show quality chickens you want to eliminate any genetic diversity in what the judge sees. That’s how you eliminate flaws, get rid of any genetic diversity that creates anything you don’t want the judge to see. But you don’t want to get rid of the genetic diversity that would cause sterility or other problems. It’s kind of tricky.

When you are developing a breed or a line, you usually use line breeding, mating a parent to its offspring. If you cross a superior bird with its offspring you enhance the traits that make the bird superior. If you cross siblings you do not get that specific enhancement, it’s more random. That’s why line breeding instead of sibling breeding is usually preferred.

I had a conversation with one of the top geneticists on this forum about this. There are a few qualifications, there always are with chicken genetics, but the loss of genetic diversity is no different in crossing siblings than it is with crossing parent/offspring. I’ll say it again. The reason line breeding is emphasized instead of sibling breeding is that line breeding better enhances certain traits.

Once you get your line established though you want to maintain as much genetic diversity as you can without losing the traits you have enhanced. There are different techniques you can use. Hatcheries use the pen breeding method. If you put 20 roosters with 200 hens and select your breeders from their offspring you can maintain pretty good genetic diversity. That’s not how you develop or maintain show quality traits though. Breeding is too random. But it works for mass produced hatchery quality stock.

One method show quality breeders use is spiral breeding. If I were Lewis77 I’d divide the chicks that hatch into three sub-flocks, probably by marking with wing or leg bands. Toe punching can work. Let’s use the designation Flock A, B, and C. At breeding season I’d put the best rooster in Flock A over the best hens is Flock A and do the same for B and C. The first year it doesn’t matter. The next year I’d put the best male offspring of A with the best pullets or hens of B, the best male of B with C, and so on. Once you get the cycle established you wind up breeding second cousins.

There are tweaks to this. Some may not breed pullets and cockerels but instead wait a year and breed hens and roosters. If a breeder trusts another breeder they may swap roosters every four or five generations to really boost genetic diversity yet maintain the show qualities they are breeding for. Once Lewis77 gets into showing he’ll have a chance to talk to real experts in this. Some are kind of jealous and don’t want to help the competition but many are so passionate about their chickens they love helping others. I’d suggest that he start going to shows as soon as possible, partly to talk to the experts but mainly to start the learning curve of what qualities he wants to look for in his breeders. Joining the State or National association of Jersey Giant breeders would probably be a good idea too.

There are other methods than this too. I’m just trying to give a general idea of one way I’m aware of.

 

[aart]

My mind is too feeble to grasp the in depth details of genetics....
.....but I do understand that parent to offspring breeding for several or more generations is fine and often beneficial.

It's the sibling crossings that I think would be best to avoid all together,
especially and harder to do with a small number of birds at ones disposal as is often the case with BY 'breeders'.

 

[centrarchid]

With breed development and strain fixing genetic diversity is lost with respect to some traits. That loss is purposeful. The concepts of genetic variation with respect to selective breeding and natural populations are very different. Latter involves closer to random matings that supports greater genetic variation than realized in any selectively bred population. The concept most difficult for most to wrap / warp heads around is "effective population size".

 

[aart]

With breed development and strain fixing genetic diversity is lost with respect to some traits. That loss is purposeful. The concepts of genetic variation with respect to selective breeding and natural populations are very different. Latter involves closer to random matings that supports greater genetic variation than realized in any selectively bred population. The concept most difficult for most to wrap / warp heads around is "effective population size".

I think most backyard breeders don't even think about it....
......they hatch out some eggs or get a batch of chicks(usually all siblings) and start crossing them as soon as they are able.
That locks up diversity right off the bat, and then they sell that offspring (and/or the original batch) as 'breeding' pairs, trios, quads...looking only at gender.

 

[centrarchid]

That is not always that bad as has parallels in how natural populations are founded. Subsequent introduction of new genes in a measured manner can then be used to increase the genetic variation of the newly founded flock.

Just as much real damage can happen in the hands of experienced breeders where less intensive inbreeding occurs over many generations. What can then be even worse is many other breeders found exclusively off a few "high" quality flocks that also removes lots of desirable genetic variation.