Biodiversity vs. Classic Animal breeding

[Robert Blosl]

I had a guy call me today and in chickens he is kind of like a partner with another guy. They live about five hundred miles apart. They boat have the same line or strain of Rhode Island Reds my old line that goes back to 1912. No out cross into my line since 1954 and then the first time in 1929.

So my friend her has two family's pen one and pen two and the friend in Georgia has pen three and pen four. Every five years they cross a top female with each other. Just like the two brothers who breed their fathers hogs for 50 years and swap ed a bore or sow every five years for new blood.

To me its a great way to work together to reach common goals for type and color. These are not commerical production reds but a old strain of Original Rhode Island Reds.

I thought of the term today when talking to this guy. I told him and then for got it again. I am going to have to write it down. Never the less the method will work great and save the two guys a lot of money over the next ten years and if one has a dog attach or someone steals their good birds they can go back to each other and get a new start.

Hope someones can drop a name for this method. bob

 

[Robert Blosl]

Biodiversity

Genetic variation

Genetic drift or allelic drift

Genetic divergence

Sub Lines
I was looking at some of my notes I saved on my method of line breeding with a partner today and found these terms.


I wonder if any of you would like to spend some time on these subjects.


This past weekend I became a partner with White Plymouth Rocks with a beginner. He lives a few hundred miles from me and I will help him with his birds each year and I will keep my two breeding pens goning down here for about four or five years. Then we exchage I think Five ckls from our breeding program in five years. We will raise these males up and pick the best one to cross onto our line for more vigor but the original blood line is mine and is 30 years old with out any outside strains only one cross from a breeder ten years ago from Oklahoma who has the same strain as I have.

Look forward to any of your comments. I hope this tread is not dead. Still so much to learn about genetics and breeding. bob

 

[3riverschick]

A subline is any branch of a line tracing back to a common ancestor, so in the above example with hogs, if I understood the description, they were just crossing sublines. There's been some studies on the use of sublines in breeding strategies, including the introduction of genetic diversity through subline divergence and the reduction of inbreeding coefficients when crossing sublines. The results indicate that due to this divergence the breeders won't reach homogeneity as quickly as keeping one line. But, since these studies were focused on lab mice, where genetic diversity isn't desireable, so they decided it wasn't an optimal breeding practice. In situations where its a good thing to maintain both genetic diversity and a "backup population" this is a very solid breeding strategy. Anyway, just my 1/2 cent.

Riddleme, please can you quote biblio on these studies?
Thanks,
Karen

 

[RiddleMe]

Karen, here's a link to one of the articles, I'll try to see if I can find a few more of them... The second link was another article I found interesting wrt sublines and genetic variance.
http://www.journalofanimalscience.org/content/71/10/2631.full.pdf
http://www.genetics.org/content/85/3/529.full.pdf

Edited to add - Both studies are a little older, especially the second one, still interesting discussion.

 

[3riverschick]

Hi,
I don't think that was a false dichotomy. When I wrote earlier I was speaking of the Biodiversity Movement (they). Not biodiversity as a result of genetics (it).
In any conversation a classic animal breeder has with anyone in the Biodiversity Movement, there will come a moment when the Biodiversity advocate will dig in their heels and say, "No more". It is usually when the classic animal breeder starts discussing the importance of "points of a breed" in a breeding program. Since they don't believe in the importance of "points" of the creature, except as it attends structure and vitality needed to work, this is where the Biodiversity Movement and classic animal breeding part ways.
On the other hand, biodiversity as a genetic result can be obtained in many ways regardless of breeding program or political views.
Best,
Karen

 

[3riverschick]

Karen, here's a link to one of the articles, I'll try to see if I can find a few more of them... The second link was another article I found interesting wrt sublines and genetic variance.
http://www.journalofanimalscience.org/content/71/10/2631.full.pdf
http://www.genetics.org/content/85/3/529.full.pdf
Edited to add - Both studies are a little older, especially the second one, still interesting discussion.

Thanks so much RiddleMe!
I will enjoy reading them!
Karen

 

[3riverschick]

Karen, here's a link to one of the articles, I'll try to see if I can find a few more of them... The second link was another article I found interesting wrt sublines and genetic variance.
http://www.journalofanimalscience.org/content/71/10/2631.full.pdfImplications
discussion quote:

"Selection in sublines and crossing yields less
genetic response at the same level of inbreeding than
does selection in a single whole line using all the test
facilities. Even the best subline is also usually inferior
to the whole line. It is concluded that selection
response is greatest when all the test facilities and​

selection are concentrated in a single selection line."

==============================================

Discussiion quote:

"The method of selection with inbreeding as a means of overcoming a selectionplateau was shown to be effective both in the present experiment, and in that of
FALCON(E1R97 1). AL-MURRANanId ROBERTS(1 974) and BARRIA(1 976), on the
other hand, did not succeed in improving populations of mice plateaued for body
weight and gain by using this method. The failure of the two populations to
respond to selection with inbreeding was attributed to lack of directional dominance.
These observations are in good agreement with the results from a simulation
study by MADALENaAnd HILL (1972), who showed that, with complete
dominance, selection within and between sublines is more effective than selection
from a single population, but the situation is reversed for additive gene action.
It thus may be concluded that selection with inbreeding is an effective method
to overcome selection plateaus for litter size in mice and probably in other species.
The method should also be applicable to other traits controlled by genes with​

directional dominance."

=====================================================
Edited to add - Both studies are a little older, especially the second one, still interesting discussion.

This second one is harder to understand. I am gonna have to get out my genetics glossary, smile.
Thanks,
Karen

 

[3riverschick]

All of this reminds me I have forgotten about the "drag of the breed" in Light Sussex.
I need to go back and note that in regards to both the breed and my birds.
Best,
Karen

 

[Robert Blosl]

Karen, here's a link to one of the articles, I'll try to see if I can find a few more of them... The second link was another article I found interesting wrt sublines and genetic variance.
http://www.journalofanimalscience.org/content/71/10/2631.full.pdf
http://www.genetics.org/content/85/3/529.full.pdf

Edited to add - Both studies are a little older, especially the second one, still interesting discussion.

I got sub lines from this article you posted which could be what I have in my Rhode Island Reds they are 100 year old strain today in the hands of three good breeders. If one of the breeders ships a male to a breeder about 700 hundred miles away to cross into his strain this must be a sub strain of the strain strain???.

Then the Genetic Variance must pop up as he lives in Illinois and the other breeder lives in Alabama with totally different climates which should cause some mutation to growth, feather development ect.

One interesting thing I have seen this year with two breeds of fowl. Master Breeder in one state has a female line. That is his females normally win best of breed and champion English.

Down here its the opposite. The males win Champion English and the females are of the lesser quality than the Indiana strain.

I have noticed this in White Leghorn Bantams. The master breeder in Arkansas had a female line. Down here in my climate I have a great male line opposite of what he could accomplish.

More to try to learn. bob

 

[cgmccary]

Biodiversity

Genetic variation

Genetic drift or allelic drift

Genetic divergence

Sub Lines
I was looking at some of my notes I saved on my method of line breeding with a partner today and found these terms.


I wonder if any of you would like to spend some time on these subjects.


This past weekend I became a partner with White Plymouth Rocks with a beginner. He lives a few hundred miles from me and I will help him with his birds each year and I will keep my two breeding pens goning down here for about four or five years. Then we exchage I think Five ckls from our breeding program in five years. We will raise these males up and pick the best one to cross onto our line for more vigor but the original blood line is mine and is 30 years old with out any outside strains only one cross from a breeder ten years ago from Oklahoma who has the same strain as I have.

Look forward to any of your comments. I hope this tread is not dead. Still so much to learn about genetics and breeding. bob

Genetic drift has been something I have thought about. Genetic drift, as I see it, is the change in a small population due to chance. Simplistic examples: Let's say you have 50 chickens and one rooster is exceptionally large. Dogs get into your flock and the big guy makes it to a large tree and survives. He will sire most of the chicks if the other roos were killed or injured. Next year, his daughters will be larger than their mothers. Over time, your flock gets larger.

Or say instead, that one of your roosters does not have feathered legs and the breed or landrace requires feathering. Some of your roosters get killed by a raccoon and the plain legged rooster survives. He will father more of the chicks and more and more will grow up clean legged.

Perhaps you have damp, very severe cold winter, and the largest birds can keep their body heat better, eventually selected by nature so as to make your flock larger (or vice versus with heat). The change from the original size or feathered legs is called the drift. If one is attempting to preserve scarce stock, drift is not wanted. Drift can change a stock so much it is barely recognizable.

What steps do you take to prevent genetic drift? Would you recognize genetic drift in your flock? Have you noticed genetic drift in your flock?