Help Please !

[Alan]

The problems begin when you do a grand sire to grand daughter.

Alan

this is even more ridiculous than the first issue.

do yall just make htis stuff up to make me laugh? :lol:

The short answer is YES

So if I understand you guys right, we should just breed any daughter to any materenal sire. Doesn't matter at all. Is that what you smart guys are saying?

Quit being show offs and and explian, because it sounds to me that it really doesn't matter.

Alan

 

[Aero]

So if I understand you guys right, we should just breed any daughter to any materenal sire. Doesn't matter at all. Is that what you smart guys are saying?

Quit being show offs and and explian, because it sounds to me that it really doesn't matter.

Alan

first off, i apologize for making a joke at your expense; it wasnt very professional.

Alan:
the truth is that it really doesnt matter what you breed. a friend of mine has the most inbred (53.96% CIB) cow in the Angus breed and she does just fine. if there were problems hidden in her pedigree, they would have been found by the time they made her.

the scary part of any linebreeding is the first attempt. if you linebreed animals that were produced by outcrossing, there is no telling what you might find. But if you get lucky and produce a consistent group of linebred calves with no apparent flaws that you like, you have just made a big step in the right direction and might have a real star in the making.

i think what you are asking can be answered by some simple guidelines:

• 1) linebreeding should be planned and centered around a certain animal or specific animal type.
  2) the higher the CIB, the more chance there is of uncovering problems.
  3) some people say the CIB limit is around 12.5% if you want to avoid phenotypic inbreeding depression.

the Angus Association has tool that will allow you to calculate the projected CIB for a mating or the estimated CIB for a specific animal but you have to be a member and can only calculate registered Angus animals.

 

[KNERSIE]

Alan,

According to Jim Lent's book no animal should contain more than 50% influence from a certain parent. Which according to him is the natural relationship between child and parent...even in us humans... you carry half the influence from your father and half from your mother.

If you mate half brothers and -sisters you still will be at 50% influence from a single parent which is still equal to the natural relationship. Jim Lents refers to this as an animal carrying 50% of the blood of the common ancestor. (not talking about CIB now)

As far as a practical example goes:
Select a top sire which already possesses the characteristics you want in your herd. Remembering that new genes can't be created, only existing ones can be concentrated.

Now breed this bull a number of cows. Keep the best resulting bull calf (one with no visible flaws) and breed him to the best of his half sisters.(culling EVERYONE with visible faults) in the meanwhile keep breeding the original cows to the original bull if you were satisfied with the offspring...if you were not then there would have been no point in linebreeding to him.

Again keep the best bull calf from the 2nd generation matings(if he is any better than the previous one..he should be if your selections were up to standard) And breed him to his half sisters and so forth...and selecting the best bull calf/calves from each generation of linebred offspring. It is always wise to start with enough quality females in the first place and maybe more than one related bull just to keep your options open.

you continue using a bull untill he has produce a son better than himself, which would then in turn replace his father. This process can continue indefinately without ever breeding a sire to a daughter or to a granddaughter while still continuing the linebreeding program.

The success of such a program will be decided of the quality of the original common ancestor(usually the bull) and your ability to select the best offspring. And I emphasize again that EVERY calf with ANY visible fault in EVERY generation should be culled ruthlessly in order to achieve the goal of a pure strain of superior cattle.

That is why I said in my previous post that the inexperienced breeder should rather just use linebred bulls to get a more uniform calf crop from their existing cows.

PM me if you have anymore questions

 

[KNERSIE]

What I failed to say is that the example I've given is just one of many ways to linebreed...it is just in the opinion of many linebreeders one of the safer options. This breeding method was largely used to develope the Anxiety 4th line of herefods

 

[Aero]

Alan,

According to Jim Lent's book no animal should contain more than 50% influence from a certain parent. Which according to him is the natural relationship between child and parent...even in us humans... you carry half the influence from your father and half from your mother.

If you mate half brothers and -sisters you still will be at 50% influence from a single parent which is still equal to the natural relationship. Jim Lents refers to this as an animal carrying 50% of the blood of the common ancestor. (not talking about CIB now)

this is where the 12.5% CIB number came from (Jim Lents)

• PGF=>F = 50%
  MGF=>M = 50%
  F=>M = 50%
  
  50% x 50% x 50% = 12.5%

the reason for this is said to be to avoid inbreeding depression and be able to compare equally. others say that this is just scratching the surface.[/list]

 

[KNERSIE]

Aero, have you got any experience of inbreeding depression? I'm not questioning your statement, just curious about how big an effect it has in practice?

What would you typically expect? Just a drop in growth rate, or a drop in total performance? I've read somewhere that it will reduce the mature size of the animals in question, but I can't remember if I've ever read to which extent.

If that is such a problem how did jim Lents manage to maintain the sizeand performance in his herd. I belief his cattle has been linebred for 120 or so years?

Its a bit off the subject, but do any of you receive the Lamplighter? I've not received one in ages

 

[Theodore W.]

I'm no cattle man,but I happen to be a biologist knowing some things about inbreeding and its dangers. but well it's hard to say how bad inbreeding depression is in practice in general.

That really depends on your actual case, but common aspects are:
0
1. Reduced fertility or fertility problems, (retained placenta is an equine example).
2. Immune system may work less well (at least against some diseases).
3. Your entire herd may have the same weakness in its immune system, increasing the chance of DISASTER-infections, even if not lethal .
4. You may be cropping up some (less obvious) bad genetic variants.
5. Reduced performance is not just possible, but even not unlikely, but if the performance is "simple" one can usually well prevent that for quite some time by just selecting for performance.

It's more or less the opposite of what you get when crossing two breeds.

That may run out of hand and get really, really serious. OK, normally speaking line breeding in cattle is quite limited and the negative effects can often be countered in part by a cross to an outsider (which may be a linebred animal itself) or even to another branch of the same line. Line breeding is something you should NOT do with a founder population or in herds bred also with an eye to rare (or foundation) breed conservation. On an incidental base it does not hurt the more common breeds much, and if you get some awful monster, well in that case you know you were having a problem already .

Theodore

 

[Bluestem]

Aero, have you got any experience of inbreeding depression? I'm not questioning your statement, just curious about how big an effect it has in practice?

What would you typically expect? Just a drop in growth rate, or a drop in total performance? I've read somewhere that it will reduce the mature size of the animals in question, but I can't remember if I've ever read to which extent.

If that is such a problem how did jim Lents manage to maintain the sizeand performance in his herd. I belief his cattle has been linebred for 120 or so years?

Its a bit off the subject, but do any of you receive the Lamplighter? I've not received one in ages

120 or so years is correct. The Lamplighter is still printed. Next issue this fall or so.

 

[Aero]

i dont claim to be a linebreeder, but i do try to understand the reasons for it and appreciate the hard work some people put into their animals.

i dont have any experience in the practice of it;, but i have some friends that are quite experienced in linebreeding that could answer (nearly) any questions you have.

go here: http://5barx.com/phpBB2/viewforum.php?f=56

and ask mikek or angus2 any questions you have. there are already quite a few topics we have covered in this area, but we welcome more. this is how i have learned what i know about linebreeding.

there are some others, but these 2 will probably be more likely to respond. (Mike is the one with the 53.96% CIB cow)

 

[dun]

i dont claim to be a linebreeder, but i do try to understand the reasons for it and appreciate the hard work some people put into their animals.

i dont have any experience in the practice of it;, but i have some friends that are quite experienced in linebreeding that could answer (nearly) any questions you have.

go here: http://5barx.com/phpBB2/viewforum.php?f=56

and ask mikek or angus2 any questions you have. there are already quite a few topics we have covered in this area, but we welcome more. this is how i have learned what i know about linebreeding.

there are some others, but these 2 will probably be more likely to respond. (Mike is the one with the 53.96% CIB cow)

What would be the CIB of a cowwho'se greatgrandsire, gransire and sire are all the same? That was a failed genetic experiment that our vet tried

dun

 

[aplusmnt]

i dont claim to be a linebreeder, but i do try to understand the reasons for it and appreciate the hard work some people put into their animals.

i dont have any experience in the practice of it;, but i have some friends that are quite experienced in linebreeding that could answer (nearly) any questions you have.

go here: http://5barx.com/phpBB2/viewforum.php?f=56

and ask mikek or angus2 any questions you have. there are already quite a few topics we have covered in this area, but we welcome more. this is how i have learned what i know about linebreeding.

there are some others, but these 2 will probably be more likely to respond. (Mike is the one with the 53.96% CIB cow)

What would be the CIB of a cowwho'se greatgrandsire, gransire and sire are all the same? That was a failed genetic experiment that our vet tried

dun

Can I GUESS? 62.5% CIB? Wanted to see if I am following this math lesson or not.

 

[aplusmnt]

Wait, second guess 87.5% CIB

 

[Aero]

it's 37.5%

here's an example
http://www.angus.org/common/epd_ped_det ... id=8235228

 

[aplusmnt]

it's 37.5%

Dang I got that wrong, I thought it would be really high since he was used back to back 3 times in a row,

I better quit trying to figure out things involving math. My big chief tablets keeps running out of paper.

 

[Aero]

here is a side-by-side of an animal bred like dun is talking about
http://www.angus.org/common/epd_ped_det ... id=8235228

AAA reg #

CIB for each animal

 

[dun]

It just seems it should be higher because he contributed halff as the sire.
Is 37.5% considered inbred? The Holstein association calls anything having over 12.5% inbred.
I'm just curious

dun

 

[Joy in Texas]

Oh wow guys ya'll have gotten way over my head. I do appreciate all of the helpful information. I keep reading it over and over . I have learned alot. Thanks everyone !

 

[Aero]

Is 37.5% considered inbred? The Holstein association calls anything having over 12.5% inbred.
dun

very much so.

not many get past the 25% range.

 

[Joy in Texas]

Aero, my heifer is 37.5 %????

 

[Aero]

Aero, my heifer is 37.5 %????

nope, 25% as previously stated.

the one dun was talking about is 37.5%