Direct vs maternal calving ease

This is the hardest point to grasp for me, except when you think about the hybrid. The ultimate uniformity possessed, but the inability to pass it on.

I like what Dwight wrote on this:

https://sites.google.com/site/steadfastbeef/parentstock-perspectives

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

It may not but there are many environmental factors that can effect what we see and random levels of regression would effect the ability to deal with some of these influences in varying degrees, as nature trys to restore a more comfortable level of variation in the genotype.

But like I say I'm just thinking out loud....

Quote :

I don’t think I’m doing a very good job of explaining what I am wondering about, sorry if I am making it worst…

I think you did an excellent job to say what I could not.

Quote :

If genotype is made more consistent, why would phenotypic variation increase?

I think that you'll see more duds appear as you tighten down or move left. I'm not so sure when or if the more growthy animals might pop up and if they are worth much more than commercial use. This is based more on sheep experience than cows.

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

EddieM has a good point with the "duds"...but isn't that the point of close breeding/linebreeding to find the duds and eliminate those genes from the gene pool. Are outliers also so produced to the other extreme?

Dylan, is there anyway you could post Dr. Bonsma's diagram "The interaction between genes and the phenotype", page 48? You do so well with your pictures!!!

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

Just to make sure we are talking about the same thing... If we were to drop a group of bred cows of similar type off on an island and went back a few hundred years later the cattle would have found a natural balance as far as genotype (assuming survival). This to me would be somewhere middle of the mating chart, at this level the phenotype more than likely would be quite similar. Now if we decided to take some of the more preferred cows from that population in an attempt to constrict the genotype of our more preferred traits, we take the population out of its balance and for every action there will be a reaction as nothing is free, so what do we have to give up for this new and improved genotype?

Hilly wrote:

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

Just to make sure we are talking about the same thing... If we were to drop a group of bred cows of similar type off on an island and went back a few hundred years later the cattle would have found a natural balance as far as genotype (assuming survival). This to me would be somewhere middle of the mating chart, at this level the phenotype more than likely would be quite similar. Now if we decided to take some of the more preferred cows from that population in an attempt to constrict the genotype of our more preferred traits, we take the population out of its balance and for every action there will be a reaction as nothing is free, so what do we have to give up for this new and improved genotype?

EXCELLENT question!!! I will have to think about this one. Excellent discussion-ideas/points to consider, in general. Somebody contact our little buddy-Jimmy L for some profound insights

RobertMac wrote:

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

EddieM has a good point with the "duds"...but isn't that the point of close breeding/linebreeding to find the duds and eliminate those genes from the gene pool. Are outliers also so produced to the other extreme?

Dylan, is there anyway you could post Dr. Bonsma's diagram "The interaction between genes and the phenotype", page 48? You do so well with your pictures!!!

Robert, I could, if the last person I lent it to had returned it.

Hilly wrote:

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

Just to make sure we are talking about the same thing... If we were to drop a group of bred cows of similar type off on an island and went back a few hundred years later the cattle would have found a natural balance as far as genotype (assuming survival). This to me would be somewhere middle of the mating chart, at this level the phenotype more than likely would be quite similar. Now if we decided to take some of the more preferred cows from that population in an attempt to constrict the genotype of our more preferred traits, we take the population out of its balance and for every action there will be a reaction as nothing is free, so what do we have to give up for this new and improved genotype?

So if the phenotype was "similar ", does that qualify as consistent, ie reduced variation.

If they were similar they may all be preferred.

What defines balance?

How long would it to take to change the phenotype of a group of Longhorns from the Wildlife Refuge and change their appearance to the point where they couldn't be recognized as Longhorns?

Your last question assumes the genotype of the 200 year island isolated cattle need improvement.

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

hhhmmmmm...is a more consistent genotype, a more homozygous genotype?
Let`s mate full sibs; the IBC { homozygousity } is an average of 25%, but could be from 0 to 50% on the bell curve of variation...so yes, we`re concentrating genes...but at what level and where in the genome is the homozygousity occuring with resulting phenotypic regression ?
make any sense at all? if LL doesn`t see this, I`ll directly email it to him...we`ll get answers {maybe just opinions ? } before the Red Lodge Front Porch meeting

Dylan Biggs wrote:

Hilly wrote:

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

Just to make sure we are talking about the same thing... If we were to drop a group of bred cows of similar type off on an island and went back a few hundred years later the cattle would have found a natural balance as far as genotype (assuming survival). This to me would be somewhere middle of the mating chart, at this level the phenotype more than likely would be quite similar. Now if we decided to take some of the more preferred cows from that population in an attempt to constrict the genotype of our more preferred traits, we take the population out of its balance and for every action there will be a reaction as nothing is free, so what do we have to give up for this new and improved genotype?

So if the phenotype was "similar ", does that qualify as consistent, ie reduced variation.
Yes, if compared to a more mongrelized population.

If they were similar they may all be preferred.
Maybe

What defines balance?
Natural laws

How long would it to take to change the phenotype of a group of Longhorns from the Wildlife Refuge and change their appearance to the point where they couldn't be recognized as Longhorns?
I have no idea, I am just trying to find a reference point to work from to make sure I understand what you’re asking, the length of time or type of cattle are of little consequence.


Your last question assumes the genotype of the 200 year island isolated cattle need improvement.
I'm not assuming they need improvement, just asking the question... if on the unusual chance that someone might feel they could improve the cattle by removing the bottom % every year to make them more “perfect”.... what is the cost

MKeeney wrote:

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

hhhmmmmm...is a more consistent genotype, a more homozygous genotype?
Let`s mate full sibs; the IBC { homozygousity } is an average of 25%, but could be from 0 to 50% on the bell curve of variation...so yes, we`re concentrating genes...but at what level and where in the genome is the homozygousity occuring with resulting phenotypic regression ?
make any sense at all? if LL doesn`t see this, I`ll directly email it to him...we`ll get answers {maybe just opinions ? } before the Red Lodge Front Porch meeting

Mike,

Would you mind expanding on the highlighted train of though....

As to you second question, it's a good one and that is why I don’t think you can “through the baby out with the bath water” so to speak, once you start into regression with intent the testing would have to be done across an outcross population. And of course that kind of testing protocol is not cheap which makes asking someone else to go there seem unreasonable.

MKeeney wrote:

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

hhhmmmmm...is a more consistent genotype, a more homozygous genotype?
Let`s mate full sibs; the IBC { homozygousity } is an average of 25%, but could be from 0 to 50% on the bell curve of variation...so yes, we`re concentrating genes...but at what level and where in the genome is the homozygousity occuring with resulting phenotypic regression ?
make any sense at all? if LL doesn`t see this, I`ll directly email it to him...we`ll get answers {maybe just opinions ? } before the Red Lodge Front Porch meeting

Mike as regards the hhhhmmmm...I am assuming so, and so what intuitively follows from a more homozygous genotype, and for the sake of example lets say with regards to feet, if good feet were linebred into the genotype would it be safe to expect consistently good feet or are we saying that at some point down the inbred regression road feet will start to be more and more variable ie not consistent?

Hilly wrote:

Dylan Biggs wrote:

Hilly wrote:

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

Just to make sure we are talking about the same thing... If we were to drop a group of bred cows of similar type off on an island and went back a few hundred years later the cattle would have found a natural balance as far as genotype (assuming survival). This to me would be somewhere middle of the mating chart, at this level the phenotype more than likely would be quite similar. Now if we decided to take some of the more preferred cows from that population in an attempt to constrict the genotype of our more preferred traits, we take the population out of its balance and for every action there will be a reaction as nothing is free, so what do we have to give up for this new and improved genotype?

So if the phenotype was "similar ", does that qualify as consistent, ie reduced variation.
Yes, if compared to a more mongrelized population.

If they were similar they may all be preferred.
Maybe

What defines balance?
Natural laws

How long would it to take to change the phenotype of a group of Longhorns from the Wildlife Refuge and change their appearance to the point where they couldn't be recognized as Longhorns?
I have no idea, I am just trying to find a reference point to work from to make sure I understand what you’re asking, the length of time or type of cattle are of little consequence.


Your last question assumes the genotype of the 200 year island isolated cattle need improvement.
I'm not assuming they need improvement, just asking the question... if on the unusual chance that someone might feel they could improve the cattle by removing the bottom % every year to make them more “perfect”.... what is the cost

Hilly I am trying to get more clarity with a number of statements that leave room for interpretation and terms that in my mind at least are undefined.

If your question was strictly "what do we give up", then without specifics, it is a purely speculative question and so I am not sure how it can be answered in a manner that will answer your first question re "making sure we are talking about the same thing".

Roberts initial question "If genotype is made more consistent, why would phenotypic variation increase?" was a "why" question.

So from a phenotypic trait specific reference point, feet for example or maybe shape of testicles or strength of pastern, is it the case from the experience of life long inbreeders like LL that a more consistent genotype achieved through inbreeding and the resulting increased homozygosity will manifest the aforementioned traits with "less" consistency. If so , why?

Re, time, for sure it takes time to acquire greater homogeneity through generational inbreeding as compared to continual out crossing and the resulting dilution. If substantial time is invested, 40 some years lets say and the fruit of your inbred labor is greater phenotypic variability, ie feet start to be expresses all over the phenotype map then regardless of genotype consistency it may be a dubious time expenditure.

And so, if "goodness has a type', which I know it does, and the presumption is that that type can be fixed by inbreeding in a parent strain netting a more consistent phenotype expression of the concentrated genotype as one goes down the inbred road over time to in fact yield "less" type consistency the farther one goes, then my mind at this point is starting to question am I really making progress relative to fixing the goodness type.

Or, is it that the "goodness" type is just hidden in the homozygous genotype of the inbred variable phenotype exterior just waiting to be let out with an outcross key, and if so, why?

My gut feel is that you will be very happy with the results if you pick a group of your cows you prefer, close down that segment of your herd and cull all animals that don’t measure up... they will be very uniform but I don’t feel they will be regressed.

As to the question
"If genotype is made more consistent, why would phenotypic variation increase?" was a "why" question.

It is a “why” question if the statement was factual in all cases which I don’t think it is, that is my reason for trying to understand what exactly we are talking about in terms of finding a reference point.

I feel you and Robert are talking about moving from crossbred or outcross breeding practices, too "type to type" or close herd breeding but avoiding regression... In these examples if the genotype is made more consistent phenotypic variation should decrease.

That being said if you continue on passed that into regression at that point I simply said I would not be surprised if the variation started to increase again as nature tries to restore variation back to her more preferred levels.

I don’t know how else to explain this unproven theory so I think I’ll start asking more questions instead...

What does regression look like anyway? Does regression only affect production levels, not structure?

I don't have many answers for many of the questions in this thread. But I can confidently say this: I've been pretty busy and haven't checked KC in a week or so, and I'm catching up. This thread makes me excited about being in Red Lodge and Two Dot later this summer. RobertMac, Warren, Dennis F. --- y'all all need to come.

Hilly wrote:

What does regression look like anyway? Does regression only affect production levels, not structure?

I'm very hesistant to venture into the fray, since I'm having a hard time comprehending, let alone contributing. I'll just venture one small point, then slowly back away. If our hypothetical inbred population has uniformly good teats or good hooves, then "regression" will not cause coke-bottle teats or scooped out hooves to suddenly appear. Those genes do not exist in our population, and if they do appear, it is not the result of regression.

By the way Hilly, thanks for saying that I have style. That's one of the nicest things anyone's ever said about me. So to cleanse the complex from my simple mind, I'd like to close with a quote from Mean Spirit.

Mean Spirit wrote:

Dennis F. --- y'all

Tom D wrote:

Hilly wrote:

What does regression look like anyway? Does regression only affect production levels, not structure?

I'm very hesistant to venture into the fray, since I'm having a hard time comprehending, let alone contributing. I'll just venture one small point, then slowly back away. If our hypothetical inbred population has uniformly good teats or good hooves, then "regression" will not cause coke-bottle teats or scooped out hooves to suddenly appear. Those genes do not exist in our population, and if they do appear, it is not the result of regression.

Tom, that’s a good point and maybe that is more what Robert and Dylan are asking... just don’t add too many more things to your wish list unless you have you great grandchildren legally bound to carry on.

I think we can all agree on the fact that the more traits we select for the slower the progress will be....

When we decide to close down a population, the cows we select will possess the traits we are looking to concentrate and I would hope so would the ancestry of those cows back many generations...

Now if we continue selection pressure into regression odds are your weakest links will show first.

So, on a time line it took 30 or so years to get the ancestral pen of preferred type cows together to get the original cows for the new, to be closed population. Another 40-50 years of selection pressure for the best feet and udders the world has ever seen.

But.... I hear of your inbred herd and I want to travel across the states and look at them and to me the cows aren’t all that great, a bit pencil gutted and track just a little odd and could be a little wider in the hips....

I was familiar with the original cows and they were dam near perfect what the heck happened? You wrecked them!!!

How hard is it to get back to the looks the original cows had... just one cross and presto everything restored.

So the question is do we restore it by opening up the herd and breeding to deep, wide smooth walking cows and start the 40 to 50 year process all over again to find a diffrent set of faults or do we accept their faults and praise them for what we bred them to do?

You can look back in old posts of mind and find I held the belief that in my dairy days, fixing udder problems was a one generation deal and relatively simple to fix... where as foot problems were a three generation problem and I attributed it to the fact that the feet were harder to fix due to the many different structural problems that manifest themselves in the feet. Recently Larry made the simple observation, that maybe the reason had more to do with the fact that dairy breeders had focused more on udders then feet over many years and that made good udders a more fixed trait than feet.... Simple stuff

Mean Spirit wrote:

I don't have many answers for many of the questions in this thread. But I can confidently say this: I've been pretty busy and haven't checked KC in a week or so, and I'm catching up. This thread makes me excited about being in Red Lodge and Two Dot later this summer. RobertMac, Warren, Dennis F. --- y'all all need to come.

I am sorry I won't be able to attend. I suspect a great time is in store for the participants.

Believe me, I would love to come. With our move to Kansas and all, we simply have too many irons in the fire/loose ends at this time. Hopefully this will be an annual event.

Tom D wrote:

By the way Hilly, thanks for saying that I have style. That's one of the nicest things anyone's ever said about me. So to cleanse the complex from my simple mind, I'd like to close with a quote from Mean Spirit.

Mean Spirit wrote:

Dennis F. --- y'all

Tom D
If that is one of the nicest things anyone has ever has ever said about you, I’m glad I refrained from commenting on that cute baby face pic you posted a while back… As I may have made you blush

Oh… and I was also wondering if anybody had any recommendation as to what bull I should breed some of my cows to this year for summer pasture calving, as I would really like to make some solid ranch type momma cows without sacrificing REA and growth… TIA

Tom D wrote:

By the way Hilly, thanks for saying that I have style. That's one of the nicest things anyone's ever said about me. So to cleanse the complex from my simple mind, I'd like to close with a quote from Mean Spirit.

Mean Spirit wrote:

Dennis F. --- y'all

Tom D reverts back to his true form. Its a pity... so much style, so little couth.

Mean Spirit wrote:

I don't have many answers for many of the questions in this thread. But I can confidently say this: I've been pretty busy and haven't checked KC in a week or so, and I'm catching up. This thread makes me excited about being in Red Lodge and Two Dot later this summer. RobertMac, Warren, Dennis F. --- y'all all need to come.

I don`t want you getting a swelled ego or anything...but I had actually noticed your absence

Dylan Biggs wrote:

RobertMac wrote:

Dylan Biggs wrote:

RobertMac wrote:

If genotype is made more consistent, why would phenotypic variation increase?

I am interested in the answer to this question also, after all phenotype is an expression of genotype and more consistent genotype, at least intuitively, should manifest less variation in phenotype.

EddieM has a good point with the "duds"...but isn't that the point of close breeding/linebreeding to find the duds and eliminate those genes from the gene pool. Are outliers also so produced to the other extreme?

Dylan, is there anyway you could post Dr. Bonsma's diagram "The interaction between genes and the phenotype", page 48? You do so well with your pictures!!!

Robert, I could, if the last person I lent it to had returned it.

I hear you...did the same thing, but I bought 2 books to start with. If I can get my other book back, I'll make it available to those here that would like to read it. Maybe send it to Red Lodge with Mike.