Line Breeding for ???

[Ebenezer]

I go back to how much is enough?

Only an opinion, but you and I are probably only urinating in the ocean if we do not build a base at 25% IBC.

I am more convinced that the longer i produce using tight blood lines, the more consistent everything gets.

Opinions galore - it will be hit and miss but will narrow the range but not destroy the range; bell curve will have a narrower base but a taller height.

That is why I don't understand the whole linebreeding depression thing. Not arguing that it happens, just not understanding why it happens.

Nature abhors a monoculture either within an organism or without.

Makes me wonder what the foundation cows were really like at foundation. Is the cow that gets to the point of depression completely uncovered in their make up?

Cows at the foundation were nothing like your cow(s). You cannot forget the influences of random gene sort and the effects many generations of breeders have had on the livestock due to selection.

So how far back in the gene pool should we consider for this topic is a very big question.

Look for trouble cattle and be sure that your cattle do not have those traits. Otherwise, you are limited to how many past breeders are still alive who will talk or how much was written and recorded about ancestors.

I think I will play with some of my pedigrees and see how they change over the generations.

In most cases, the cattle did not chose their mates. People chose and people changed.

IS there a one size fits all for phenotype?

Your linbreeding efforts should create a phenotype that you will live with if it is genetically influenced. If it is good, then you and I get a gold star. If the cattle stink and lose money then we picked the wrong cattle to linebreed. Roll the dice.

I know that there are visual preferences, but where function meet form, is their a standard that we all should be driving toward?

Fertility of females. Functional and convenience traits.

 

[ClinchValley]

Will a half sibling mating result in a smaller calf than normal? I know I read that somewhere, possibly in this thread as well. Could this be an approach to a first calf heifer?

Hope it isn't a dumb question...

 

[Ebenezer]

It reduces the chance of added hybrid vigor but does not erase any genes in either parent where grandsires or granddams carry high birthweight history. Discussion going on another thread about using a Hereford bull on Angus heifers. Just the opposite in thoughts. More power to them. Good question.

 

[cotton1]

Although I have not gotten that far in this thread, the idea of a heifer bull in consideration to genetic depression has crossed my mind. I'm just not sure at this time that the depression is more at calving time or at weaning or yearling time. I would say for that to work, the bull would have to be very linebred. It seems too possible to me that in the situation ClinchValley proposes, that the calving weight may be closer to normal then you see a slower developing calf due to depression. Phenotype will definitely have some say in the situation. A very linebred bull of the type that throws long, slender calves may have a higher weight but still be very successful in the heifer calving department. A lady once told me in reference to this topic:"She can have a 90lb vienner sausage way easier than she can have a 70lb bowling ball" :lol2:

On a little different note: A friend of mine and I were thinking out loud about the type of a cow vs her actual beef production. The conversation is originated in the flush we did this week. The bull I used is a very proven, high accuracy bull that has been considered one of the best in the breed for more than 20 years now. The bulls offspring are thick and heavy muscled, and have the look of "beefy" cattle. The females are thick and stout yet milk very well and grow calves out nice and attractive. The animals look "beefy" and have the reputation as being beefy, however the bull has absolutely zero marbling ability according to his EPDs. This includes data off of over 4000 calves, with plenty of scan data, daughter, grand daughters and linebred progeny as well. Other carcass data is probably ok, but worst on marbling. Question: Do producers understand what phenotype renders what type of beef? Maybe the ones that look "beefy" aren't the best in the slaughter house. Line breeding needs to be done with the right type. What are the signs of the right type in correlation to beef grade/quality?

 

[ClinchValley]

Cotton1 - Please excuse my ignorance to this topic. I have been reading all I can about it for 6 months, yet I still feel I am grasping straws in certain areas.

By a bull being very line bred, do you mean 3rd and 4th generation results of line breeding? Or do you mean sharing a higher percentage or like genes? IE - Father to daughter or son to mother or full sibs?

Just trying to understand.

 

[Ebenezer]

By a bull being very line bred, do you mean 3rd and 4th generation results of line breeding? Or do you mean sharing a higher percentage or like genes? IE - Father to daughter or son to mother or full sibs?

You have no way to know the genes that transfer. All you can do is look at the pedigree for a guess and a hope. Maybe the phenotype and function will hint toward genes that got transmitted but you just go with what you get.

If the same bull is listed as both grandfathers then there is linebreeding. You can either focus on one ancestor or a herd or source that has multiple uses of animals which are related in some way. No real definition of "very linebred". You pick the minimum %IBC you are comfortable with and that is your line in the sand. The lower the number you pick, the safer you are. The lower the number you pick, the less potential rewards of prepotency. And to be honest, the words and terms have been used by many just for promotion.

 

[ClinchValley]

By a bull being very line bred, do you mean 3rd and 4th generation results of line breeding? Or do you mean sharing a higher percentage or like genes? IE - Father to daughter or son to mother or full sibs?

You have no way to know the genes that transfer. All you can do is look at the pedigree for a guess and a hope. Maybe the phenotype and function will hint toward genes that got transmitted but you just go with what you get.

If the same bull is listed as both grandfathers then there is linebreeding. You can either focus on one ancestor or a herd or source that has multiple uses of animals which are related in some way. No real definition of "very linebred". You pick the minimum %IBC you are comfortable with and that is your line in the sand. The lower the number you pick, the safer you are. The lower the number you pick, the less potential rewards of prepotency. And to be honest, the words and terms have been used by many just for promotion.

Thank you. That cleared things up a lot, for me at least. The bigger the risk, the potential bigger the reward. Or bigger the loss.

 

[Ebenezer]

1. There has to be a purpose or it is not worth the effort and risk.
2. You will focus on the population and not an individual. So, no one great bull and no trophy heads to mount on the wall. No individual is more important that the herd.
3. You want more individuals in the middle of the bell curve. So the desired bell curve shape will go from wide to narrow and short to tall on whatever the trait(s) are that you think you want to have prepotency.

 

[cotton1]

One of my purpose traits is definitely calving ease. I'm thinking that if I know the generations that are stacked are all made up of proven easy calving genetices, then I have reason to use that bull on like kind females with at least a little notion that it will be an ok idea. I'm sure that with any bull, line bred or not, that using a young bull on grown cows first is a good idea. But even if you get that line bred bull, and prove him with a calf crop on older cows, shouldn't the heifers being mated be considered? What is their phenotype, how does that compare to the bull, what are their family calving traits?
Ebeneezer- Do you find it would be different consideration of using a line bred bull on heifers of an out cross? That is something I really would like to know. At what stage of development does HyBrid vigor or genetic depression show up? Is that something you would see at calving time, or maybe later on into weaning/yearling development? I guess what is in my mind here is, can a line bred bull with easy calving traits stacked in and even proven easy calving in the herd he was developed in cause larger than average birth weights when bred to out cross heifers.I wonder about this because I think most bulls that are line bred sell to outcross herds .

 

[Nesikep]

I learned (from CT) that hybrid vigor, or genetic depression starts at conception, not birth.. though, perhaps if the dam is subject to one or the other, it may affect her milking ability and may show up in the weaning weight of the calf as well.

However, it seems that there are exceptions to every rule.. Look at Holstein dairy herds. there is certainly no hybrid vigor, there hasn't been an outcross for decades in many of them. Yet, through careful selection, they milk more than any other breed. This hasn't come without a price though... Longevity, fertility, and a host of other problems that a beef producer couldn't live with.

There are many factors to consider when choosing a type of animal.. Just as an example, if your cattle spend half the year on range and you're paying for it by cow/calf pair per month, you really don't need to care about how efficient they are or how much they eat, the bigger a calf they come home with the more money you make... If you're a guy like me that feeds them on-farm all year, suddenly the ability to hold a few more head of cows because they're more efficient, though perhaps have smaller calves will pay dividends.


For MY goals, I'm looking for a modest animal that is feed efficient, raises a respectable calf on grass, and lives a long time. Some people here don't seem to value longevity, saying "If your breeding program is worth it's salt, the daughters will always be better than their dam, thus to progress you must accelerate through the generations"... I don't look at it as a race, but a marathon... If I have a cow that's exceptional when she's young, it's pretty unlikely that my whole herd will have progressed to exceed her in her lifetime, thus the more time I have to keep daughters from her, the better my herd as a whole will become.. I probably have more important cows to cull anyhow. Also, by having many LIVING generations of a family, I have more choices for how I want to linebreed, whether it's breeding that good old cow to her grandson, or having many of her daughters to breed to their nephews. You only get about 50% of the genes of a parent in it's offspring, so if I want to get close to keeping ALL of that cow's genes in the herd (don't want to perhaps miss some of the good genes), having 2 offspring will give me about 75% of her genes.. if I can have 7 of her offspring, I'm likely to have 99% of her genes still in my herd and that might be handy to have down the line.

 

[Ebenezer]

Do you find it would be different consideration of using a line bred bull on heifers of an out cross? That is something I really would like to know.

Genes come from both parents. Heifers that carry high BW genes can influence the calf weight. When, which, how many? Depends on the way the genes pair at conception. A better bet: use a bull that is genetically bred for low BW. Lents said that his bulls were so prepotent that they could make Hereford color and pattern on more crossed cattle than other Herefords. You could possibly do the same with enough tight breeding if you can prove it out.

But know that in most cases, the desire for an extreme low BW will also affect growth in some of the generations to follow. There are exceptions. The old Pfred Angus bull was one. Small calves and huge mature weights. An oddity. But most curve benders are either oddity or fable.

For MY goals, I'm looking for a modest animal that is feed efficient, raises a respectable calf on grass, and lives a long time. Some people here don't seem to value longevity, saying "If your breeding program is worth it's salt, the daughters will always be better than their dam, thus to progress you must accelerate through the generations"... I don't look at it as a race, but a marathon... If I have a cow that's exceptional when she's young, it's pretty unlikely that my whole herd will have progressed to exceed her in her lifetime, thus the more time I have to keep daughters from her, the better my herd as a whole will become.. I probably have more important cows to cull anyhow. Also, by having many LIVING generations of a family, I have more choices for how I want to linebreed, whether it's breeding that good old cow to her grandson, or having many of her daughters to breed to their nephews. You only get about 50% of the genes of a parent in it's offspring, so if I want to get close to keeping ALL of that cow's genes in the herd (don't want to perhaps miss some of the good genes), having 2 offspring will give me about 75% of her genes.. if I can have 7 of her offspring, I'm likely to have 99% of her genes still in my herd and that might be handy to have down the line.

Well thought out and well said.

 

[Faraway]

Birthweight is effected positively by heterosis. So it is easy to imagine that when inbred terminal sires selected for low birthweight are used on unrelated females you may see a bit more birthweight than you would expect in the progeny. Might not be a huge issue- but in very unrelated cattle, such as Continental X Zebu crosses, the heterosis effect can be substantial- maybe 5 lbs or more. Continental X British cattle I think has been documented at about 2 lbs of birthweight due to heterosis. I'd guess increased birthweight due to heterosis in crosses of inbred strains within a breed would be even less, but probably more than zero.