My Grandpa is my Dad

[John]

My Grandpa is my Dad
(Despite all the jokes living in the south) Farmers don’t believe in letting fathers breed with their daughters (we are talking animals here). Now granted this is primarily cattle farmers (cows) and a very small amount of sheep farmers (Shepherds). Now if you ask a cow farmer why not, you will get one of two answers, it has always been that way around here or doing that could cause birthing problems. With sheep, everything I read says to raise your own ewes for culling. When I have asked the Shepherds why not breed the daughters, they normally don’t have answer expect it is not a good idea. Granted I have never question the ones that do breed the daughters. Am I misunderstanding or missing something here. Does this come down if you are breeding purebreds as breeding stock or if you are just meat producing machine, perhaps opens up a canned of worms to having a Closed Flock (if I understand that definition correctly). Wow, inbreeding, closed flock, line breeding, and line cross.

What do some of you do with your breed practices and what do you believe? I know that this is not new to many of you.

Bill, does this take me back to my first day here when you explained what a mule was?

Thank You
John

[Bill Fosher]

Hi John,

One of the biggest problems you're going to run into is that all the terms you've mentioned in your post are very important to understand, and they almost all mean different things to different people.

Take for instance "closed flock." I've heard people claim to have a closed flock who lease out their rams or have ewes in from outside for breeding service. They consider they're flock closed because they aren't buying in any ewes. So genetically, it's a closed flock, but from a biosecurity standpoint it is anything but.

Nearly everyone who has a closed flock means that that they don't import outside ewes, but they almost always import rams from outside at least occasionally. I think that Bill Duffield is one of the few shepherds I've communicated with who only brings in outside rams via AI -- correct me if I'm wrong.

Inbreeding, technically, means the breeding of any closed population. So any purebred sheep is inbred to some extent (except for show sheep, but don't get me going on that). Linebreeding is a form of inbreeding where closely related ewes and rams are bred in an attempt to fix or concentrate certain traits. The challenges of line breeding are 1.) that you lose all traces of hybrid vigor in the lambs, so you will see generalized production losses as you work to concentrate the traits you are working on; and 2.) you will concentrate and fix some traits that you wish you hadn't. So when you're embarking on a linebreeding program, you have to be ready and willing to accept a lot of clunkers to get a few real gems.

Father-daughter crosses are generally considered a little too close by most purebreeders, but grandfather to granddaughter is a very common way to fix the traits of an exceptional ram. The other problem with line breeding is that some people do it because they think they have an exceptional ram who perhaps really isn't so exceptional.

At some point, you could devleop several line within the same flock of purebred sheep, and start crossing those lines with one another, or bringing in outside rams from different lines to see if you could devleop other lines that were worth breeding closely.

As to why father-daughter breeding is too close, I think that at least a good part of it is the "yucko" factor -- that is applying human taboos to animal husbandry. But realistically, the closer two animals are related, the greater the downside risk of concentrating more bad than good.

Not having to deal with all these considerations is one of the greatest reasons for buying replacement animals. Of course, biosecurity is compromised. Like every other management decision, it's a tradeoff.

[WayneG]

So if I did not want to buy any more rams or ewes, and not AI (because of the expense- not because it won't work- how many individual units would I have to maintain on a small scale to make this work? Could I do it with 3 rams each with say 7 ewes or would it be better to have 4 rams with 10 to 12 ewes. I know that is a high ram density- but If I want to have a truely closed flock, this is an option. I know that managment would be considerable- along with the space requirements. Rams A,B,C and D and ewe groups 1,2,3 and 4. I could always bred A to 1, B to 2 and so on. Replacement ewe lambs would go from group 1 to be replacements in 2, 2 to 3 and so on. But I would not be sure on how to rotate the replacement ram lambs. I assume I would get 3 or 4 breeding seasons out of a ram. I know this is where the AI would be handy, and maybe in 3 or 4 years I could afford to do that. A closed flock to ewes is easy- throwing in the rams makes it a little harder. Or am I just asking for a lot of work and I will never see a payout.

[BK-Ohio]

Bill,
With all due respect, I disagree with your assessment of linebreeding and its dynamics, at least from the experience I have had in a program that is 31 years going, with only one or two exceptions, a closed ewe flock.

My experience has been that linebreeding enhances predictability in the lambcrop. This is why I prefer to use only rams that were born here for the vast majority of the lamb crop. Do I sometimes go out of the flock to get a ram? Yes, but generally I go to another flock who is in my genetic line, therefore further enhancing my predicability and depth in the lambcrop. Therefore, there is very little:

" 2.) you will concentrate and fix some traits that you wish you hadn't. So when you're embarking on a linebreeding program, you have to be ready and willing to accept a lot of clunkers to get a few real gems."

Actually, it is the genetic predicability that gives me a barn full of lambs that look similar and very few clunkers. It is of interest that when I have gone out to find traits that I would like to incorporate that I have been most disappointed. Generally, when I am experiencing a total outcross, both within my breed, with a crossbred or even with another breed, it is very hit and miss. One ram I used produced practically every lamb as a clunker. Another outcross line has meshed extremely well and I hope to work with this line further to enhance the traits I am looking for.

Now, it is not all roses. I have had a few issues that have demanded attention. I noticed one female group in my flock was consistently having Ring Womb issues at lambing. It was very evident and I could trace it back through my years of lambing records to isolate it to ewes out of one ram and daughters of those ewes. Easy fix, move them on to the killer and don't let other breeders get them.

Another instance that pertains to the title of this post was the time I was forced to breed a ram back to all of his paternal sisters, or even closer. This was interesting when lambing came. The crop was really uniform, and very small. They just didn't grow. They were all peas in a pod, except the one born with one ear. Well, I won't go that close again.

I prefer to breed 1st or 2nd cousins. They offer the predicability I want without sacrificing the "degration of the gene pool" when you get them too close. More importantly, I look to incorporate the best traits from the "stud ewes" in my flock when selecting a ram to use. "Stud ewe" means that she is free from faults that I want to accentuate in my flock. She also has to milk, mother and be CONSISTENT.

[Bill Fosher]

BK-Ohio,

I was talking about the initial process of starting a linebreeding program. You're seeing the benefits of it after 31 years of fixing the traits you want. I guess I should have been more clear about the upside of linebreeding -- I'm a big fan of it myself.

[BK-Ohio]

Bill,
I understand your point now. Thanks. This brings up another point that I failed to mention earlier. Where do you find the genetic base to start a linebreeding program with? That is the million dollar question and it has to be answered by any breeder wanting to jump into this breeding process. Do lots of homework and visit the farm in question often. Look around and try to take it all in. Am I seeing the overall picture, both good and bad? This game of trying to get them to produce a great product is tough, but it sure is fun.

[John]

This still leaves just question of how does one start cost effectively when you only have a dozen. Honestly, I can not go to a farm and tell you that I am seeing good traits. I am sure that changes with experience. Same holds true if you buy your set stock and sell all you lambs, I cannot tell you if I am bring in something that will potentially kill my existing flock. I can only make educated guess from research but sometimes that does not hold up, much like street smarts verses book smarts. If you find a knowledgeable person to go with, they probably would want you to buy from them. We don’t have any “sheep friendsâ€￾, expect you folks. This by the way is appreciated. I could go to a farm look at paper work, listen to the stats and probably be sold like a 16 year buying a first car (with out the advice of mommy and daddy).

Perhaps what Wayne was saying earlier is the better way to go but I think 4 rams would be a bit extreme. Because of a ram investment proving to have poor traits for your breeding (what ever kind of breeding that would end up being).

I get this feeling all this comes from getting your hands dirty. My fear is if you are with a flock that is poor you will never truly know what a good one is. So keeping an open mind, visit many farms and research the heck out of it pays off in the end. Kind of brings me back to the first question I had on this forum, what breed to start out with (not that is the topic of thread).

Thank you
John

[BK-Ohio]

My advice would be to visit some farms that have the top to offer in any genre. Be that showing seedstock, production seedstock or whatever you are after. Then buy a set of ewes from a breeder, not a gatherer. What I mean is that there are breeders out there who practice linebreeding and there are those that buy some here, some there, and what you have is a hodge podge that will not breed true. Talk to the breeder about their program and think about how what they are doing will work for you. I think that the uniformity you would get in a set of aged ewes or even ewe lambs would give you a launching point for the program. If you find the right breeder, it really won't cost you much more than just gathering. You would be surprised at what you could get if you just look good and hard at your options.

[Janet McNally]

To answer the question about how many ewes are required to keep a closed flock (and I presume the desire is to minimize inbreeding to some acceptable level)...geneticists tend to recommend minimum populations of 300 females for this purpose. those females need to be developed into lines... I'm foggy as to what number of lines are required, but I'm going to guess at 10 is very minimal, and rams from each line retained and rotated to the next.

Sure linebreeding can be used to fix traits, and when mating the best to the best entails line breeding I will use it too, but there are more negatives to linebreeding than possitives. Too much will depress reproductive efficiency signficantly. As to fixing the good traits one geneticist put it to me this way... its like shooting a rifle into the engine in your car, there is a chance you might hit the right thing and adjust the carborator so it runs better, but the odds you will hit the wrong thing are much much greater. When I asked how much greater he pulled a figure from horse breeding...that for every one breeder who makes it work...29 others failed.

Janet

[BK-Ohio]

Janet,
You may be right on the numbers of successful linebreeders. It isn't easy but I enjoy the mental calesthenics required to get it right. I am thankful for those that have succeeded because they are the movers and shakers in seedstock production. Some of the changes are for the better and some for the worse. Just one of those things that makes America great.

[woolpuller]

First to answer Bill. Yes my flock according to the rules is a truly closed flock. Frozen semen that the ram have been tested before and after collection for 7 health items is the only semen allowed at this farm. Flocks that say they are closed but bring in live rams are, to me, a closed ewe flock.
Hagedorn's book from the early 1800's from Holland titled animal breeding stated that the quickest way to find out if a ram doesn't have any defects is to mate a full sister to a full brother which is just over a year. The normal way of breeding , the ram will die naturally before you discover any defects.
I select my ram lambs using Lambplan & SFIP plus the physical appearance. I mate by random selection of ewes. My inbreeding this way has got to 6% maximum.
I am not concerned about inbreeding.
When using AI I also random select. My son, a large animal vet, contually stated that this would give me a truer result than trying to match the best data to the best data.

[WayneG]

Found this website on the internet- found it to be interesting.
http://www.agf.gov.bc.ca/sheep/publicat ... uction.pdf

[woolpuller]

Wayne:
Re-read article. I read it when Dr W. Howell wrote it. Had a few times with the Doctor and discuused items over a few meals.
You note the heretitary level of loin eye area or now done loin eye depth. The surprise is only a few people take this measurement in North America.

[WayneG]

It sounds like I should be looking for something when I re read it. Is it just the loin eye issue or is it anything else. I assume the 2 ways to read area or depth are actual off carcass or ultrasound. Can the same person that ultrasounds for pregnancy also do loin eye area?

[BK-Ohio]

I learned something interesting a month ago or so. I had always wondered why sheep in the central plains livestock shows always out-cut sheep here in Ohio. They have many that cut over a 4 inch LEA and here in Ohio, we rarely get much over 3 inches. Well, I had a talk with Dr. Henry Zerby from OSU and he runs the carcass show at the Ohio State Fair. He said that a true LEA measurement only considers the one, major muscle in the loin. However, there are really 4 muscles that make up the red meat portion of the loin when viewed as cut. He wondered if the other carcass shows were measuring all 4 muscles instead of just one. I found this interesting and wonder if that is the answer. By the way, the genetics are generally the same in both regions, with winners coming from the same farms and genetic lines.