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Dylan Biggs



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PostSubject: What are the odds?   Thu Apr 21, 2011 7:52 am

Can anyone tell me more about genetic probabilities.

Specifically, genetic probabilities of progeny resembling sire or dam from a phenotypic standpoint, relative to the total number of genetic combinations possible.

For example lots of people use a picture of a Dam with info on a Sire.

What is the statistical probability if any of the progeny resembling the phenotype of the Sires Dam (the paternal granddam).

Or they use a photo of progeny, so like wise what is the probability of half paternal sibs being similar in to each other in phenotype.

How are these probabilities affected as inbreeding coefficients increase?


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MKeeney
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PostSubject: Re: What are the odds?   Thu Apr 21, 2011 10:40 am

Dylan Biggs wrote:
Can anyone tell me more about genetic probabilities.

Specifically, genetic probabilities of progeny resembling sire or dam from a phenotypic standpoint, relative to the total number of genetic combinations possible.

For example lots of people use a picture of a Dam with info on a Sire.

What is the statistical probability if any of the progeny resembling the phenotype of the Sires Dam (the paternal granddam).

Or they use a photo of progeny, so like wise what is the probability of half paternal sibs being similar in to each other in phenotype.

How are these probabilities affected as inbreeding coefficients increase?


just about the time LL thinks there`s nothing more to say; and just about the time I think I have acquired lots, but not enough, of LL`s breeding insights, we are presented with a serious breeding, not marketing, question.....and I have to holler
HELP! Smile
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Hilly



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PostSubject: Re: What are the odds?   Thu Apr 21, 2011 1:27 pm

Good questions Dylan Smile

There my be some theoretical numbers if that is what you are looking for that could be calculated, but they are only as good as the numbers entered Wink

If you are looking for practical experience in cattle the number qualified to answer questions like these would be few indeed and I look forward to their input.

It would be interesting as well to get the view points of breeders with experience in inbred and regressed litters as to the phenotypical variation in the litters… I am not a believer in IBC % as a very accurate way to measure inbreeding…

From my limited observation and information from conversations with people that have some experience in this area (although I have never asked this exact question, and these are only my ill drawn conclusions) if you were looking to reduce the phenotypical variation and increase your odds of replication in that regarded… The type to type breeding with low IBC would be the way to go, the more cows or bulls in the picture pedigree with the same appearance, the better the odds of phenotypical replication. And in my experience these cattle have been very useful in my commercial operation and have reduced my on farm sort, from the days of high priced mongrelized main stream pedigrees with generations of outliers and their picture pedigrees reveal the breed by numbers type variance of matings that occur with that kind of herd mentality breeding program.

But if you are interested in constriction of the size of a gene pool to the point that Mother Nature begins to have concerns over what you are up to (in theory higher IBC’s), she will start to shut you down, and at this point variation in phenotype may well increase as some combinations at this level draw more attention and subsequent regression. And that is where faith (for lack of a better word), in the principals will be required and a belief that it is all worth the effort. And that question, I would think, can only be answered when everything is systematically restored for its preconceived purpose...

You could call me on BS for any of the above thought processes as I have no experience in this regarded, and I realize that I have not answered any of your questions, but that is because I can’t Smile
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MKeeney
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PostSubject: Re: What are the odds?   Fri Apr 22, 2011 6:54 am

pretty much spot on I believe Hilly...I disagree with you and LL on the IBC %...NO, it doesn`t measure true inbreeding level, and it`s just an average, but it`s the best "measure" we have...kinda like epds
I think the kicker in the butt for many "planning to inbreed" talking breeders is that inbreeding won`t create more uniformity in the phenotype of the inbred progeny...that type to type would give more consistent "production stock"...
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Dylan Biggs



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PostSubject: Re: What are the odds?   Fri Apr 22, 2011 9:34 am

MKeeney wrote:
pretty much spot on I believe Hilly...I disagree with you and LL on the IBC %...NO, it doesn`t measure true inbreeding level, and it`s just an average, but it`s the best "measure" we have...kinda like epds
I think the kicker in the butt for many "planning to inbreed" talking breeders is that inbreeding won`t create more uniformity in the phenotype of the inbred progeny...that type to type would give more consistent "production stock"...

So inbred type to type would not be anymore consistent or uniform in phenotype than type to type alone.
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Grassfarmer



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PostSubject: Re: What are the odds?   Fri Apr 22, 2011 9:49 am

So if as Hilly says "type to type breeding with low IBC would be the way to go, the more cows or bulls in the picture pedigree with the same appearance, the better the odds of phenotypical replication." but that inbreeding with a higher IBC leads to less phenotypical replication wouldn't the way to go be something along the lines of Jim Lents program? Linebreeding not inbreeding using his definitions? My next question would be what do you call high or low IBC in this context? Also how important is phenotypic similarity in a purebred herd? Other than from a marketing perspective does it really matter as long as the next generations of seedless fruit our stock sire are more uniform than the average?
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Dylan Biggs



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PostSubject: Re: What are the odds?   Fri Apr 22, 2011 10:06 am

Hilly wrote:
Good questions Dylan Smile

There my be some theoretical numbers if that is what you are looking for that could be calculated, but they are only as good as the numbers entered Wink

If you are looking for practical experience in cattle the number qualified to answer questions like these would be few indeed and I look forward to their input.

It would be interesting as well to get the view points of breeders with experience in inbred and regressed litters as to the phenotypical variation in the litters… I am not a believer in IBC % as a very accurate way to measure inbreeding…

From my limited observation and information from conversations with people that have some experience in this area (although I have never asked this exact question, and these are only my ill drawn conclusions) if you were looking to reduce the phenotypical variation and increase your odds of replication in that regarded… The type to type breeding with low IBC would be the way to go, the more cows or bulls in the picture pedigree with the same appearance, the better the odds of phenotypical replication. And in my experience these cattle have been very useful in my commercial operation and have reduced my on farm sort, from the days of high priced mongrelized main stream pedigrees with generations of outliers and their picture pedigrees reveal the breed by numbers type variance of matings that occur with that kind of herd mentality breeding program.

But if you are interested in constriction of the size of a gene pool to the point that Mother Nature begins to have concerns over what you are up to (in theory higher IBC’s), she will start to shut you down, and at this point variation in phenotype may well increase as some combinations at this level draw more attention and subsequent regression. And that is where faith (for lack of a better word), in the principals will be required and a belief that it is all worth the effort. And that question, I would think, can only be answered when everything is systematically restored for its preconceived purpose...

You could call me on BS for any of the above thought processes as I have no experience in this regarded, and I realize that I have not answered any of your questions, but that is because I can’t Smile

The more thoughts the better, I don't know enough to call B.S. Curious why you qualify the first sentence in your second last paragraph with (in theory higher IBC's).

So if I understand what Mike and you are saying inbreeding won't improve distribution of phenotype, relative and or compared to non inbred type to type.

The benefit (a belief that it is all worth the effort) of linebreeding is the genotype concentration and the resulting tightened distribution. The benefit of compressing the genotype spring, so to speak then, is when it is released by outcrossing to a Charolais for example, is the amplification of the hybrid effect?

GF, the value to me of more uniformity would be in functional structural traits, like feet, legs, udders, full well developed muzzle, a hooded eye, and in bulls, in addition to feet, testicular shape and symmetry, tight clean sheath, no prolapse of the prepuce, etc, etc.
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MKeeney
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PostSubject: Re: What are the odds?   Fri Apr 22, 2011 12:02 pm

crossing inbred lineages should result in more uniform phenotypic results in the progeny than crossing non-inbred types to types...but inbredx to inbredx will not in what little experience i have to draw from...
traditional "performance selection" of inbred stock is meaningless in my opinion...all evaluation must be on the progeny results when either linecrossed or outcrossed...
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Hilly



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PostSubject: Re: What are the odds?   Fri Apr 22, 2011 12:23 pm

Dylan Biggs wrote:


The more thoughts the better, I don't know enough to call B.S. Curious why you qualify the first sentence in your second last paragraph with (in theory higher IBC's).
So if I understand what Mike and you are saying inbreeding won't improve distribution of phenotype, relative and or compared to non inbred type to type.

The benefit (a belief that it is all worth the effort) of linebreeding is the genotype concentration and the resulting tightened distribution. The benefit of compressing the genotype spring, so to speak then, is when it is released by outcrossing to a Charolais for example, is the amplification of the hybrid effect?

GF, the value to me of more uniformity would be in functional structural traits, like feet, legs, udders, full well developed muzzle, a hooded eye, and in bulls, in addition to feet, testicular shape and symmetry, tight clean sheath, no prolapse of the prepuce, etc, etc.

Dylan, you had to bring that up pale

As I reread my post that particular qualifier bothered me because I knew it was uncalled for.

For some reason it annoys me when I hear of a high IBC% breeding that somehow was able to trick Mother Nature because they were able to constrict the gene pool to this degree without affecting growth performance... I just don’t believe you can have it both ways.

My thoughts on the IBC% were summed up well by Mike.
"on the IBC %...NO, it doesn`t measure true inbreeding level, and it`s just an average, but it`s the best "measure" we have...kinda like epds"

Some more good questions asked, hope to have more time later to discuss them and add a few more Smile
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Mean Spirit



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PostSubject: Re: What are the odds?   Fri Apr 22, 2011 12:41 pm

I think I'm with you Craig. If a pedigree says an animal is highly inbred, say greater than 10 or 15%, and the animal is not showing some signs of regression in fitness or performance, I'm doubting how inbred that animal is. Selecting the best performing inbreds is probably selecting the least inbred individuals.
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Grassfarmer



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PostSubject: Re: What are the odds?   Fri Apr 22, 2011 1:49 pm

Dylan Biggs wrote:

GF, the value to me of more uniformity would be in functional structural traits, like feet, legs, udders, full well developed muzzle, a hooded eye, and in bulls, in addition to feet, testicular shape and symmetry, tight clean sheath, no prolapse of the prepuce, etc, etc.

Dylan it seems to me you are a visual phenotype perfectionist and that's not meant in any negative way Smile
My goals are maybe a bit lower. I don't really mind what feet, legs or udders look like - as long as they serve their purpose with no negative consequence or intervention from me. I have some cows with udders down at the back, some down of the front (and some perfect too) but as long as the calves suckle unassisted and they milk adequately to rear an average calf they stay. Same with legs we have the odd one with claw shaped feet as they get older but as long as they don't go lame they stay. Certainly the more correct the animals look in every feature the happier I am with them and I don't keep bulls out of cows with obvious faults but there is a limit to how much we can achieve in a lifetime breeding cattle. To my mind the biggest determinent to profitability are fertility and longevity - I want cows that rear 10+ calves and if they do that under commercial they are good enough for my requirements. Maybe I have no place being a purebred breeder with views like these but I don't think I can make enough progress in my lifetime if I start culling for picture perfect feet, teats etc - we would run out of cattle before we ran out of things to cull for.
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Hilly



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PostSubject: Re: What are the odds?   Fri Apr 22, 2011 7:27 pm

I have not read Mr. Lents book yet, but I do receive his newsletter... when I went down to visit him and tour his cows I had not yet met Larry, in hind sight I would have had better questions had the order been the other way around.

The Lents herd, IMBSO was very uniform in appearance, by the looks of the calves and growing stock I would say the herd was near the center of the mating systems chart possibly leaning to the left of center. I never asked at the time but wish I would of... what kind of a sort it took to maintain the uniform appearance?
If I remember right he told me he sells no females for breeding, but I had the impression that maintaining the population numbers was consuming the whole of the female half of the calf crop due to my perceived pressure from his eye.

So with that in mind when GF asked what would high and low IBC be in this context... I don’t think you could run higher IBC then Lents and maintain the numbers as well as the breeders preferred phenotype of the herd.
I realize for me to make these generalized statements about a breeders herd from one visit, on a public forum, without him being present in the conversation is unfair but gives some context to my thought process.

Of course for me this is all hypothetical anyway, but I can’t help but feel like talking of constraining gene pools to the point of regression is putting the cart before the horse so to speak... GF situation been somewhat different then what I perceive most of us here are in with the limited knowledge I have of others here.

For me I feel the first step is an understanding of what my cattle look like in the absence of heterosis(not regressed but commonly called that it would seem), it is my understanding this will involve closing down a portion of my herd with selection focused on the average and avoiding inbreeding to the point of compressing the spring so to speak to center on the chart.

Hopefully I will achieve beginners status in the next thirty years, and along with it some much need experience... but I would anticipate the cattle to have slower growth performance (commonly unacceptable) but at maturity, absent of a time frame, they will express my preferred type.
To some degree I see this as getting comfortable in my own skin and becoming independent in hopes to be beneficial in interdependent joint ventures with other independents, with my main goal being succession of the principals.

I do have more questions Smile If I am still around in 30-40 years and decided that I had enough familiarity with my cattle to compress the spring a little farther on a portion of the herd, in an effort to increases predictability even more, with some higher IBC and the majority of resulting offspring never achieve the phonotypical appearance that I had grown to understand, and at the same time the visible variance increased... What happened? Did some genes vanish? How could you tell what you were looking at without an outcross progeny test?

You will get stopped sooner or later anyway... but harnessing the predictability to acquire the title of fix may require more than the eye can see when dealing with regression.

Dylan, in my mind compression of the genotype spring is for the purpose of achieving “fix” status for some trait or traits as well as harnessing the hybrid potential...
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Bob H



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PostSubject: Re: What are the odds?   Sat Apr 23, 2011 1:28 am

Dylan I am a commercial cattleman with a keen interest in cattle we have not bought any thing other than Shoshone trueline bulls for 12 years for maternial side of our program and have breed them back to their mothers, sisters and cousins for that amount of time not by indivdual selection but by mutlitple sire from like kind and genetics and have found that we are fixing a type about 85 % of the time that is the pheno type that we perfer.

It is interesting to show folks these cattle there are about 350 hd that are related and when we tell folks they roll their eyes, but when you drive them thru and show them they agree that if you see one you have seen most of them.

We are gong to ship allot of these pairs to summer grass in the morning. I will try to get some photo's of them. I think that we humans are trying to make it too difficult and we should listen to the cattle and observe

If you don't start with much junk in the bull line that you use you don't end up with much junk just a cowboys thought.

I am 54 and don't beleive that in my lifetime that I will observe enough junk from these cattle to have to throw much away, My partner is 25 and she may have to but that is her decision to make.

In her adult life been around Shoshone trueline in our herd as maternal. She is very observant though and can see that in her terms that most of the rest of the neighboring cattle that they are a skitel package with a few M&M s thrown in and why would you do that . Her most famous quote for the winter is the explaination of what we do to broaden our genetic pool is that we put the boys with the girls and get the little ones and the world goes around and around. ( that seems fairly simple to me ) enough BS for one nite Bob
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Grassfarmer



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PostSubject: Re: What are the odds?   Sat Apr 23, 2011 7:31 pm

So on the Lents program, which I have read about only - his book and newsletters, it would appear from the claims that the cattle have a high degree of phenotypical similarity yet I gather he still culls a few that don't pass a visual inspection. I would imagine he will have a lot of cattle in the 17-18%IBC range just by the sheer amount of common ancestory. I'm assuming this common ancestory doesn't give him cattle over 25% as I know he does not believe in the "incestous matings" so would never breed a sire to daughter etc which would give him 25% in one generation. So is there a difference between cattle with the same IBC scores achieved a different way? ie does breeding them the way Lents does - slow and steady, generation after generation never closer than the equivilent of half sib matings in each generation of matings produce less regression and more phenotypic similarity than somebody that does a crash course in inbreeding by mating a sire/daughter and other less related matings to achieve the same IBC?
I can't get straight in my head the significance of phenotypical similarity in a close breeding program - does it matter if they look the same or does the comment that the tighter you wind up the screw the more variation you will see in the inbred parent stock negate that? Once the spring gets wound up a bit won't they all have the potential to produce the same "look" when outcrossed? how about when they are not outcrossed but bred to animals within the same genepool but not quite as tightly wound up?
If we accept that Lent's herd is strict linebreeding as opposed to Shoshone which has used varying degrees of inbreeding (using Lent's definitions) what are the differences in use of the resulting progeny? Are there situations where "linebred" cattle would work better than "inbred" cattle and visa versa and if so what are they? Any chance that we could get Mr Lent's to visit KC? I'm sure he would add a lot to the discussion rather like Gavin Falloon did.
I know LL always tells us the principles are simple but a couple of quotes from a grazing course I did seem more applicable to my thoughts on linebreeding/inbreeding "it's not more complicated than we think, it's more complicated than we can think" and "as we reach a new plateau of understanding we encounter a new level of confusion" scratch Smile
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Hilly



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PostSubject: Re: What are the odds?   Sat Apr 23, 2011 8:50 pm

I would like to echo Mike’s comment.... Help!

I should know better but I will throw out a few more unfounded thoughts Embarassed

I would think that if you are going to breed cattle with your eye in a long term closed herd situation you would self regulate the IBC, the longer the program runs the more accurate the calculated IBC would be... 60 years of linebreeding at a certain IBC range would have higher accuracy in the progeny then a onetime breeding of the same calculated IBC.
I would consider this level as being much the same as natural wild populations... there appearance is quite uniform but the depth of the picture pedigree explains why... that and the previously stated fact that nature doesn’t make decisions based on monetary policy.

I do think however that there is a IBC level that can be achieve before Nature shuts you down completely that cannot be bred by the eye that will achieve a level of “fixed” that exceeds the level the eye can consider and therefore can only be evaluated in its intended purpose form.

I should run out of hot air soon... I hope Smile
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MKeeney
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PostSubject: Re: What are the odds?   Sat Apr 23, 2011 9:06 pm

you`re doing great Hilly..carry on..I don`t agree, or disagree...which means, you`re making me think... Smile
I had to laugh today and thought of this thread when I looked across the fence at the purebred hereford calves by the Line one bull from polled Hereford cows...first I saw a couple of red-necked bull calves with red around their eyes....then...oh no...three or four linebacked, mostly whitelegged damn things...and I thought, 70 years of linebreeding, and color markings are not even "fixed"...
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Grassfarmer



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PostSubject: Re: What are the odds?   Sun Apr 24, 2011 12:15 am

Very good Hilly, that gives me a lot to think on. The thing that scares me is this "breeding by eye" even within a closed breeding program. The type of selection that I imagine Jim Lents does to eliminate certain undesirables from the herd. Up until recently I'd only ever bred by eye - I've never bred by numbers, but it seemed I was wrong more often than not - isn't that the point of "form follows function it doesn't predetermine it"? Now I'd rather keep on breeding with no culling on visual appearance and see where I'll end up.
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PatB



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PostSubject: Re: What are the odds?   Sun Apr 24, 2011 7:57 am

Grassfarmer wrote:
Very good Hilly, that gives me a lot to think on. The thing that scares me is this "breeding by eye" even within a closed breeding program. The type of selection that I imagine Jim Lents does to eliminate certain undesirables from the herd. Up until recently I'd only ever bred by eye - I've never bred by numbers, but it seemed I was wrong more often than not - isn't that the point of "form follows function it doesn't predetermine it"? Now I'd rather keep on breeding with no culling on visual appearance and see where I'll end up.

Why not breed by eye and numbers? Remove those that have too much or too little BW, Frame, milk or whatever that you are manageing for. I have a couple awesome bull calfs that soon will be a set of awesom steers because of BW over 100 lb.
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MKeeney
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PostSubject: Re: What are the odds?   Sun Apr 24, 2011 8:04 am

patb wrote:
Grassfarmer wrote:
Very good Hilly, that gives me a lot to think on. The thing that scares me is this "breeding by eye" even within a closed breeding program. The type of selection that I imagine Jim Lents does to eliminate certain undesirables from the herd. Up until recently I'd only ever bred by eye - I've never bred by numbers, but it seemed I was wrong more often than not - isn't that the point of "form follows function it doesn't predetermine it"? Now I'd rather keep on breeding with no culling on visual appearance and see where I'll end up.

Why not breed by eye and numbers? Remove those that have too much or too little BW, Frame, milk or whatever that you are manageing for. I have a couple awesome bull calfs that soon will be a set of awesom steers because of BW over 100 lb.
if numbers are so good, why do you have over 100 lb birthweights to have to steer Pat?
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PatB



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PostSubject: Re: What are the odds?   Sun Apr 24, 2011 8:28 am

MKeeney wrote:
patb wrote:
Grassfarmer wrote:
Very good Hilly, that gives me a lot to think on. The thing that scares me is this "breeding by eye" even within a closed breeding program. The type of selection that I imagine Jim Lents does to eliminate certain undesirables from the herd. Up until recently I'd only ever bred by eye - I've never bred by numbers, but it seemed I was wrong more often than not - isn't that the point of "form follows function it doesn't predetermine it"? Now I'd rather keep on breeding with no culling on visual appearance and see where I'll end up.

Why not breed by eye and numbers? Remove those that have too much or too little BW, Frame, milk or whatever that you are manageing for. I have a couple awesome bull calfs that soon will be a set of awesom steers because of BW over 100 lb.
if numbers are so good, why do you have over 100 lb birthweights to have to steer Pat?

Both cow families have always had heavy calves regardless of the bull used. The calfs come unassisted and grow excellent but not something I want to have for herd bulls. Most bulls in my area are used to breed heifers and cows so 100 plus pound bw would not be a good thing besides according to your teaching we are suppose to use the bulls from the middle not the outliers. Very Happy
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EddieM



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PostSubject: Re: What are the odds?   Sun Apr 24, 2011 8:49 am

Quote :
Both cow families have always had heavy calves regardless of the bull used. The calfs come unassisted and grow excellent but not something I want to have for herd bulls. Most bulls in my area are used to breed heifers and cows so 100 plus pound bw would not be a good thing besides according to your teaching we are suppose to use the bulls from the middle not the outliers.

Are the EPD's in an acceptable range or are you going strickly on individual BW's? Seem to be using scientific and farm lore as a mix.
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MKeeney
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PostSubject: Re: What are the odds?   Sun Apr 24, 2011 11:42 am

patb wrote:
MKeeney wrote:
patb wrote:
Grassfarmer wrote:
Very good Hilly, that gives me a lot to think on. The thing that scares me is this "breeding by eye" even within a closed breeding program. The type of selection that I imagine Jim Lents does to eliminate certain undesirables from the herd. Up until recently I'd only ever bred by eye - I've never bred by numbers, but it seemed I was wrong more often than not - isn't that the point of "form follows function it doesn't predetermine it"? Now I'd rather keep on breeding with no culling on visual appearance and see where I'll end up.

Why not breed by eye and numbers? Remove those that have too much or too little BW, Frame, milk or whatever that you are manageing for. I have a couple awesome bull calfs that soon will be a set of awesom steers because of BW over 100 lb.
if numbers are so good, why do you have over 100 lb birthweights to have to steer Pat?

Both cow families have always had heavy calves regardless of the bull used. The calfs come unassisted and grow excellent but not something I want to have for herd bulls. Most bulls in my area are used to breed heifers and cows so 100 plus pound bw would not be a good thing besides according to your teaching we are suppose to use the bulls from the middle not the outliers. Very Happy
that`s not quite right....you would select from the middle ONLY if the middle represents optimum performance for your resources resulting in maximum profitability....
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PatB



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PostSubject: Re: What are the odds?   Sun Apr 24, 2011 5:58 pm

EddieM wrote:
Quote :
Both cow families have always had heavy calves regardless of the bull used. The calfs come unassisted and grow excellent but not something I want to have for herd bulls. Most bulls in my area are used to breed heifers and cows so 100 plus pound bw would not be a good thing besides according to your teaching we are suppose to use the bulls from the middle not the outliers.

Are the EPD's in an acceptable range or are you going strickly on individual BW's? Seem to be using scientific and farm lore as a mix.

Both BW and BW epd's are high on these cows, the bw epd's tend to agree with actual birth weights around here. Past fire and ice mateings occiasionally kicks in and have outliers on either end of the range that are not acceptable. The middle of the pack for BW is pretty optimum far as I am concerned.
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larkota



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PostSubject: Re: What are the odds?   Sun Apr 24, 2011 7:25 pm

CED BIRTH WEAN YEAR
+2 +1.9 43 79 DAM DOB 2-28-2001
-3 -.4 -1 +8 SIRE DOB 1-5-1969

6 son from this mating. average birth wt. 87lbs. high of 94. low of 74.

would you use these back on full and half sibs? why and why not?
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Hilly



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PostSubject: Re: What are the odds?   Sun Apr 24, 2011 9:27 pm

I would think that for a breeder to determine a gene pool worthy of isolation, the more cattle they can put in the ancestral pen that express the form need for your perceived function the better the odds would be that the strain would succeed in purpose.

It would also seem to me that from the point of isolation on ( if the ancestral pen was not an isolated population to begin with) that the growth performance of your newly isolated gene pool would only have one logical direction as you breed the heterosis out... If that is true then the population you end up with will not likely express the same phenotype during the growth phase that the original contributors to the gene pool had, this would appear to apply to BW as well which may have to be taken into consideration when out crossing.
Other traits that I have not fully grasp... may be effected as Larry has mentioned I believe with milk for instance(I can’t seem to remember the context of that observation right now...) as you begin the journey to find out what the true breeding value of the different traits are, absent the heterosis in your strain. During this phase traditional performance expectations on the cattle in the growth stage would be unrealistic, but that aside, I would thing that you would still be able to use your eye for basic function and to identify outliers, then at maturity more precise evaluation may occur at the phenotype limited IBC levels.

If breeder chose to do this with only a small portion of their herd, as Larry had originally proposed... and kept the majority of the herd right of center where multipliers and commercial producers have grown addicted to for their seed stock supply, they would create a safer learning environment for them and their customers as in most cases seeing is believing...
The thing to remember is any perceived loss (or gain, depending on your point of view) during the isolation process can be restored at anytime with a simple outcross...( See Exhibit 5)


It would appear to me that in the mainstream quest for progress they have been force to creep more and more heterosis all the time into their calves to maintain the illusion... moving farther right on the mating systems chart into an area that is supposed to be use for the production of seedless fruit and the only way to keep up this delusion is a game of musical chairs in the bovine species gene pool.





As I was typing this response, I was reminded again of what Larry said when discussing his selection experiences with three visually different bulls and possibly why the smaller ones tended to contribute more to his goals....some great thought provoking observations here and they can be read in their full context on page 4 of the “closed herd breeding” thread on 5barx...

" I don't think homozygosity or heterozygosity per se has much to do with the size of the selected 3 bulls. The closest bred cattle would likely be more homozygous but there are too many other factors involved to say the smaller bull would be more homozygous. I did this same thing with totally outcross sires like Rito 549. To clarify my selection of 3 different sons, the smaller of the 3 was not the smallest of them all, nor was the middle sized the average of them all, but the largest was indeed the largest of them all. While the DNA of today's generations indicate a similarity in the sequence of common ancestry, I have not been able to access the homozygosity of that sequence.

According to academia, the 50% centerpoint between "homo" & "hetero" genotypes is said to occur when mating close cousins without selection. Full-sib or sire/dau produce the higher percentage of homozygosity and of course cross breeding produces the higher percentage of heterozygosity. Rather than worry about "homo/hetero" percentage content, selection would seem to be more like increasing the gene frequency for specific traits while reducing any interacting predominance of others. Of course the less variation we have to start with, the quicker the results. If you recall my spherical distribution analogy. we might assume that the center of a population would be the most "balanced". Over time I have been selectiing for the maternal qualities in moderate sized cows. Since Bonsma believed extremes disrupted functional efficiency, I could presume a beneficial side effect of my selection was a more balanced endocrine system resulting in stronger sexual distinction. Perhaps the smaller bulls were more "central" to the female genotypes of my preferred type ... less disruptive.."
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