EPD's

[Tod Dague]

Here is a bw EPD Example.

We will be AI'ing to 4 different bulls this year and they are all bulls we own. Their will be no outside genetics brought in. The BW EPD's are as follows 1.7, 3.5, 3.6, & 2.8. Now none of theses are what I consider a calving ease sire, and they are all performance bulls. Now since I am not going to bring any outside bulls in. These will be compared to only each other in the contemporary groups. So since their is only a 1.9 difference between the biggest to the smallest. What will happen to the numbers after the data is turned in on them? If one sires on average 5 to 10 pounds of actual bw less than the others, will he then drop to look as if he is a calving ease sire? In this sinerio he could and probably will, but in reality he will still not be a calving ease or heifer type bull, but his numbers will say he is. What about the other bulls, in the same example, will their bw EPD jump way up and look as if he is a cow killer, but in all actuality they come out nice and easy but weigh a little more than the rest.

Aren't the bulls that you are using also bulls that you offer for AI. That should help keep your EPDs in line.

 

[BRG]

Ya but the bulls with a 3 plus BW don't hardly get used by anyone else.

For me, they may change some since their are other owners of the bulls and some semen is marketed in them, but their are breeders out there that own their bulls on their own, don't sell any semen, and don't bring in outside genetics.

 

[Brandonm2]

Brandon, I don't believe either thing you stated is entirely correct. You are looking at it from top down, and the way it appears they are working it is from bottom up. Once they have isolated a gene they believe to be responsible for tenderness, all the need to do is compare a population of cattle with it to those without it. Which they have done. It doesn't matter what bulls they are out of as long as it impacts tenderness in the general environment that I raise my calves in. Once they prove a number of genes that affect tenderness significantly, it matters whether that bull has it or not.

All they have done is identify a handful of genetic markers that are found in cattle that their research shows are often common to calves that are found to be tender. There are MANY MANY calves that yield a tender carcass that do NOT have ANY of their tenderness DNA markers. Lack of any of the DNA tenderness genes does not necessarily mean that the steaks will be tough. We still have not identified every tenderness gene. I am not opposed to anybody identifying and multiplying 'tenderness genes' but I think a system of using only proven sires that have passed shear force testing would be FAR FAR more accurate at this time. Of course any system will have to be implemented from the TOP DOWN in this industry since there are a million plus producers and only a handful of packing companies. Any one of the big three packers have the power too implement a system tomorrow by executive fiat, wheras it would take several thousand producers to come together to agree then they would have to negotiate with a packer and the retail chain to implement their ideas.

 

[dph]

All they have done is identify a handful of genetic markers that are found in cattle that their research shows are often common to calves that are found to be tender. There are MANY MANY calves that yield a tender carcass that do NOT have ANY of their tenderness DNA markers. Lack of any of the DNA tenderness genes does not necessarily mean that the steaks will be tough. We still have not identified every tenderness gene. I am not opposed to anybody identifying and multiplying 'tenderness genes' but I think a system of using only proven sires that have passed shear force testing would be FAR FAR more accurate at this time. Of course any system will have to be implemented from the TOP DOWN in this industry since there are a million plus producers and only a handful of packing companies. Any one of the big three packers have the power too implement a system tomorrow by executive fiat, wheras it would take several thousand producers to come together to agree then they would have to negotiate with a packer and the retail chain to implement their ideas.

I see, and someone please correct me if I am wrong, but what I am saying is if they show that if cattle are homozygous for the three genes identified they are 2.2 lbs less on the shear force test that a group of cattle that have none of the genes, they have proven to me what I want them too. That's not saying that there aren't genes left to identify or that there is a smaller population of cattle in that less tender group that are actually as tender or more. It says on average they are going to be more tender with the genes than without them. MANY MANY are not a majority by a long shot. That's why this test has been validated.

What I meant by bottom up was to prove it. The calves prove the genes. If you want by the bulls or top down, you would still have to DNA test to see if their progeny got the genes. On any of these traits I see a group getting together for a genetic trait, prove that they have identified a significant portion of the relevant genes, prove that the cosumer will pay more for this trait, and prove the packer can test for it without messing up their system. I don't want to hijack the thread, so I won't post again unless this topic comes up under its own heading. I feel I have said my peace and I appreciate being able to further discuss it. In the end, time will tell.

 

[Frankie]

I don't mean to be discouraging, but Nolan Ryan's beef is guranteed tender. And they don't worry about DNA or high quality grades.

 

[MikeC]

"USDA quality grades have been recognized as not differentiating appropriately
the tenderness of steaks taken from the longissimus muscle of USDA Select
or Low Choice fed-beef carcasses (Wulf et al. 1997).11 Further, Shackelford et al. (2001)
argued that consumers can detect differences in tenderness within Select strip loins after
14 days of postmortem aging. This is significant, since Choice and Select account for
over 90 percent of the graded carcasses (Boleman et al. 1998). More broadly, Wheeler
Cundiff, and Koch (1994) found that marbling explained at most just 5 percent of the
variation in beef palatability. Comparing the USDA grading system with MSA and the
Japanese Meat Grading Association System, Strong (2001) concluded that the wide variation
of eating quality within each USDA quality grade is not surprising, since the system
does not consider many factors proven to affect quality.
It is well established that to increase the probability of obtaining satisfactory tenderness,
the best genetics should be used, and appropriate management practices should be
followed during growth, slaughter, and processing of carcasses. However, Koohmaraie et
al. (1996) cautioned that the relation between breed and tenderness is not strong, since
variation of tenderness within breeds is larger than variation across breeds.12 Hence, as
Schroeder et al. (1998, p. 10) concluded, "…producer alliances with the goal of targeting
beef to specific markets demanding particular quality attributes will likely find success
elusive if they rely predominantly on current beef quality grades, cattle breeds, and genetics
to ensure tenderness and consistency of their products. Producers may also need to
employ some type of tenderness testing." This claim is significant, since only one of the
40 certified beef programs registered with the USDA rely on such measurements.13
Broadly speaking, all these programs require is some distinctive genotypic and/or phenotypic
characteristics combined with eligible USDA quality and yield grades (with variable
stringency) and the absence of visible defects such as hemorrhages or dark cuts.14
All these requirements are conducive to more tender meat, but there are still significant
amounts of unexplained variation in consumers' perceptions. Scientists have concluded
that "the beef industry must identify more precise methods [than USDA quality grades]
of distinguishing palatable from unpalatable beef" (Wulf and Page 2000, p. 2595), and,
along the same line, "a direct measure of meat tenderness is needed to supplement quality
grade" (Wheeler, Cundiff, and Koch 1994, p. 3150)."

 

[ollie?]

I have learned a lot about birth weigh EPD in this discussion.
I want to thank you all for that.
I do however have a broblem with the accuacy of YW. Maybe it is because I do not understand how it is derived. To me it could be just a feeding contest with ear implants and whatever else one could find to increase gain, with no regaurd to feed efficiency.
Please inform me on this.

YW is better described as "Post Weaning Weight". This weight is for analyzing the gain of a contemporary group of calves after they have been removed from the cow, and usually for the 140 subsequent days, no matter the feeding regimen.

Feed efficiency has nothing to do with this "Post Weaning Gain".

How could it, with no efficiency data reported?

A high rate of gain in the overall contemporary group would not cause the entire groups' YW EPD's to be higher because the ratio between the calves is used for calculation.

Mike I agree with you but there is also another angle to consider. If a large majority of the data is gathered in an environment where the genetic potential is maximized through high concentrate rations, when fed a ration that is less than optimal , there will be less difference than the YW would indicate. The opposite is also true?

 

[MikeC]

when fed a ration that is less than optimal , there will be less difference than the YW would indicate.

Why would there be "less difference" than the YW (EPD? or the actual weight?) would indicate?

If I'm reading your words right, there could possibly be MORE difference.

 

[ollie?]

when fed a ration that is less than optimal , there will be less difference than the YW would indicate.

Why would there be "less difference" than the YW (EPD? or the actual weight?) would indicate?

If I'm reading your words right, there could possibly be MORE difference.

There would be less difference in the actual weight in compairison. For example if one bull had a yw of 20 and one had an 80 and 80% of the data was collected on these bulls offspring in a high concentrate environment, the actual YW's would be closer than the 60lb difference. Growth takes fuel.

 

[MikeC]

the actual YW's would be closer than the 60lb difference.

What makes you say this?

I have not found this to be true nor untrue. Cattle that gain good on a high concentrate diet are likely to gain good on forage as well.

I would think the cream would rise to the top just as well in either feeding program.

 

[dun]

I have not found this to be true nor untrue. Cattle that gain good on a high concentrate diet are likely to gain good on forage as well.

I would think the cream would rise to the top just as well in either feeding program.

Kind of an aside, but when we select heifers at weaning to retain we look for those that just continue to gain and look about the same when they go on the grain diet for the weaning process. The ones that really blossom on the grain diet have invariably ended up as hard keepers as they mature. We don;t have any of that type left, they grew wheels over the years so now we ship them to the feedlot as youngsters.

dun

 

[novatech]

I have not found this to be true nor untrue. Cattle that gain good on a high concentrate diet are likely to gain good on forage as well.

I would think the cream would rise to the top just as well in either feeding program.

Kind of an aside, but when we select heifers at weaning to retain we look for those that just continue to gain and look about the same when they go on the grain diet for the weaning process. The ones that really blossom on the grain diet have invariably ended up as hard keepers as they mature. We don;t have any of that type left, they grew wheels over the years so now we ship them to the feedlot as youngsters.

dun

Ok. Back to EPD's
Dun, Are you saying that when you choose an AI bull and looking at the EPD's you would stay away from the high gainers, breeding for replacement heifers? When breeding for terminal calves you would pick high gainers in the YW?
It is almost a trade off to get good cows you loose feed lot gain, which is what you want in the end product. Or can you get both?

 

[dun]

I have not found this to be true nor untrue. Cattle that gain good on a high concentrate diet are likely to gain good on forage as well.

I would think the cream would rise to the top just as well in either feeding program.

Kind of an aside, but when we select heifers at weaning to retain we look for those that just continue to gain and look about the same when they go on the grain diet for the weaning process. The ones that really blossom on the grain diet have invariably ended up as hard keepers as they mature. We don;t have any of that type left, they grew wheels over the years so now we ship them to the feedlot as youngsters.

dun

Ok. Back to EPD's
Dun, Are you saying that when you choose an AI bull and looking at the EPD's you would stay away from the high gainers, breeding for replacement heifers? When breeding for terminal calves you would pick high gainers in the YW?
It is almost a trade off to get good cows you loose feed lot gain, which is what you want in the end product. Or can you get both?

Typically those high YW calves are also larger framed. If you keep heifers you eventually end up with the dreaded frame creep and the cows end up too big. But, ah yes, there is alwasy a but, there are outliers that can grow like crazy for the first year and then slow down in growth. That's where it's really nice to have a yearling FS and a mature FS.
We breed some cows to strictly terminal bulls, they're good cows but not the ones that we would like to perpetuate the genes of in our herd. Others we breed to heifer makers to get replacements. This year we got lucky and only one of the meat maker cows had a heifer and only 3 of the heifer makers had bulls. I guess the bad part of it is that we're going to have way to many heifers to select from for replacements this year.

dun

 

[novatech]

I have not found this to be true nor untrue. Cattle that gain good on a high concentrate diet are likely to gain good on forage as well.

I would think the cream would rise to the top just as well in either feeding program.

Kind of an aside, but when we select heifers at weaning to retain we look for those that just continue to gain and look about the same when they go on the grain diet for the weaning process. The ones that really blossom on the grain diet have invariably ended up as hard keepers as they mature. We don;t have any of that type left, they grew wheels over the years so now we ship them to the feedlot as youngsters.

dun

Ok. Back to EPD's
Dun, Are you saying that when you choose an AI bull and looking at the EPD's you would stay away from the high gainers, breeding for replacement heifers? When breeding for terminal calves you would pick high gainers in the YW?
It is almost a trade off to get good cows you loose feed lot gain, which is what you want in the end product. Or can you get both?

Typically those high YW calves are also larger framed. If you keep heifers you eventually end up with the dreaded frame creep and the cows end up too big. But, ah yes, there is alwasy a but, there are outliers that can grow like crazy for the first year and then slow down in growth. That's where it's really nice to have a yearling FS and a mature FS.
We breed some cows to strictly terminal bulls, they're good cows but not the ones that we would like to perpetuate the genes of in our herd. Others we breed to heifer makers to get replacements. This year we got lucky and only one of the meat maker cows had a heifer and only 3 of the heifer makers had bulls. I guess the bad part of it is that we're going to have way to many heifers to select from for replacements this year.

dun

Thanks for the info.
That's a nice problem you have with to many heifers.
I take care of some cattle for an elderly man that has been upgradeing his herd for over 30 years. He has the same problem every year. This is very fortunite for me as he is always culling from his proven cows. They may be culls but they are still very well bred and better than most I could find elsewhere. Kind of the same situation you find yourself in. Somebody could get a great buy if you cull into your existing herd.
The best part is the great price I can buy them at.

 

[DOC HARRIS]

dun -

Your selection protocols are the results of EXPERIENCED cattle management technics! Well thought-out plans! When you are confronted with a "problem" of too many heifers of the kind you are seeking, knowing what you are looking for - and WHY - then frame scores are deciding factors when choosing between "good" choices - as are EPD's! Another justifiable reason to understand EPD's, and how to differentiate between similar individuals! Well done!


novatech - you ALSO are in the cat-bird seat with your situation, and here, also, is the requisite knowledge of EPD's a necessity! As you said, they may be culls and are an advantage to you financially - but you still must use your knowledge of EPD's to justify adding them to your herd. You are in a very enviable position!

DOC HARRIS

 

[ollie?]

the actual YW's would be closer than the 60lb difference.

What makes you say this?

I have not found this to be true nor untrue. Cattle that gain good on a high concentrate diet are likely to gain good on forage as well.

I would think the cream would rise to the top just as well in either feeding program.

Mike if you just simply take the YW from 1000 down to 700 and leave the percentage difference the same, the numbers get closer. It's been my observation that T Gentry , Kit Pharo, etc. don't have many high YW cattle.

 

[MikeC]

Mike if you just simply take the YW from 1000 down to 700 and leave the percentage difference the same, the numbers get closer.

The Ratio's would be very similar though.

Example:

A-3 calves that average 700 lbs:

1-685 lbs.= Ratio - 97.85
2-700 lbs.= Ratio - 100
3-715 lbs.= Ratio - 102.1

B-3 calves that average 1000:

1-985 lbs.= Ratio - 98.5
2-1000 lbs.= Ratio - 100
3-1015 lbs.= Ratio - 101.5

The Ratio's are actually closer with the higher weight calves.

 

[ollie?]

Mike if you just simply take the YW from 1000 down to 700 and leave the percentage difference the same, the numbers get closer.

The Ratio's would be very similar though.

Example:

A-3 calves that average 700 lbs:

1-685 lbs.= Ratio - 97.85
2-700 lbs.= Ratio - 100
3-715 lbs.= Ratio - 102.1

B-3 calves that average 1000:

1-985 lbs.= Ratio - 98.5
2-1000 lbs.= Ratio - 100
3-1015 lbs.= Ratio - 101.5

The Ratio's are actually closer with the higher weight calves.

When you take the same precentage of difference Mike, there is less difference in the actual weight.
1-689.5=Ratio-98.5
2-700=ratio-100
3-710.5=ratio-101.5

In the above example instead of a 30 lb spread, you only have a 21lb spread.

If you take a bull who's epd's should put him 60lbs per head greater at 1000 and shrink him down to 700, the same 6% difference leaves the lesser bull at 658. Only a 42lb difference. Does any of that make sense?

 

[MikeC]

If you take a bull who's epd's should put him 60lbs per head greater at 1000 and shrink him down to 700, the same 6% difference leaves the lesser bull at 658. Only a 42lb difference. Does any of that make sense?

Not really.

You nor I have no idea how the model actually computes this scenario.

But I have an idea that it would take into effect his actual weights in conjunction with the computation of his EPD's.

 

[Brandonm2]

Yall have so lost me this is not even funny. I think all that matters is that SOMEHOW the computer crunches the numbers and the bull which consistently sires the heavier calves in the most contemporary groups gets the higher EPDs. If a bull sires progeny that do great on grass; but become fat pigs on grain it is going to hurt his EPDs when those slow growing toads get reported. Likewise if a bull sires progeny which excel in the feedlot but bulls and heifers sired by him don't have the guts to perform on wheat pasture those grass fed replacements back on the farm are going to hurt his EPDs when they are factored in to the numbers. Since there are cattle out there being developed in the feedlot AND there are cattle being developed on forage, I have a suspicion that the proven sires have had progeny in both environments and for a sire to still have respectable growth EPDs his progeny must be able to perform in both.