Genomic scores vs EPDs

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WB Angus

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It is not always easy to get the genomic scores when selecting bulls to use and often i will see that a genomic score will contradict an EPD. Like an HP epd of 12 and a genomic score of 80. I feel like if they are scoring well for a genomic trait then I should trust that more than an EPD. Am I wrong for thinking this way? I mean isn't DNA more proof of what might be passed on?
 

wbvs58

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Yes especially if not much data has been recorded. It is very easy to get great unproven EPD's by breeding to numbers and not recording data. In Australia we don't get to actually see the genomic results, Angus Australia controls it all and it goes straight into the bi monthly EBV calculations. I often have my suspicions that they might edit the results a bit so they don't look like goose's when their EBV's are proven incorrect. To find out the effect that genomics have on my heifer's EBV's I print out their EBV's at time of collection of hair and compare to the breedplan run when the results are in. There is never any massive change just a bit of tweaking which fuels my suspicions.

Ken
 

Katpau

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You would expect the genomic score to be more accurate, but you would be wrong. My original thoughts were…people can manipulate data, but you can’t manipulate DNA, so the genomics should be more accurate. Right? It turns out that I was wrong. The DNA may not change, but our understanding of what the DNA represents is constantly evolving. The EPD's include the most recent genomic information and are updated every Friday, but genomic scores are only updated for you to see once every year.

Kelly from American Angus explained it to me. When you run a Genomic test, the SNP’s, of that animal are compared to those from hundreds of thousands of others. Each SNP represents a difference in a single DNA building block, called a nucleotide. Scientists somehow determine that certain SNP’s are responsible for certain traits, so it is assumed if the SNP’s of a certain bull or cow are similar to those of others with a certain trait, then they will share that trait. Assumptions are not always accurate. At one time this was done manually, but now computers are able to analyze and calculate similarities by analyzing thousands of pieces of data at the same time. EPD’s are recalculated every Friday using the actual data turned in by producers and looking at the information provided through the genomic analysis. The EPD’s are always being refreshed, however the numbers you see in a genomic score are not updated until the computers make an annual run adding all of the information collected over the prior year. The genomic scores you now see on your animals when you log in to AAA were just updated May 28th, so are pretty current. Those numbers will be different than what you saw over the last year and some may change quite a bit. When you find a genomic score for an AI bull on your computer, it could be years old if the stud does not update their information. The EPDs on the other hand will have changed very little, if at all, when those genomic numbers were recalculated and reposted on the 28th.

The fact is, even though DNA doesn’t change, we are still learning what that DNA does, and original assumptions are often found to be inaccurate. If you see a genomic score on a bull that says he is in the bottom 20% for Heifer pregnancy, but his EPD puts him in the top 20%, it is because the data since that genomic score was run has changed expectations. With something like heifer pregnancy, there is less data to analyze, so these numbers are still likely to keep changing. Birth weight has more actual data and is less likely to move. Weaning weight is one that can be off in your environment. Environment plays a huge part in weaning weights, and I expect most data on this comes from purebred breeders and cows that are treated way better than the cows in the average large commercial herd. For that reason, I expect weaning weight EPDs and genomic scores should often be suspect. I, for example, have an eleven-year-old cow with a weaning weight average of 105% in my herd on 9 calves. She has a genomic score that puts her in the bottom 16% for weaning weights, but in my tougher environment she easily out weans cows with better scores. In past years her genomic score has put her as low as the bottom 1% for weaning weight.

I have found that most of the genomic scores I first received in 2015 have changed dramatically, and today's scores are definitely closer to my actual data. As an example, a bull I ran a genomic test on in 2015, had a score that put him in the bottom 15% for Birth weight and his birth weight EPD was + 3.2. I expected this based on his own performance and he was chosen as a growth bull to be used on cows. His genomic score for weaning weight put him in the top 22%. He sired about 100 calves, and we found his to be some of our smallest calves, but weaning weights were unimpressive. His genomic score now shows him in the top 9% for low birth weight and his BW EPD is at .5. His WW genomic score is now 89 and his WW EPD has dropped to 39 pounds.
 
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WB Angus

WB Angus

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You would expect the genomic score to be more accurate, but you would be wrong. My original thoughts were…people can manipulate data, but you can’t manipulate DNA, so the genomics should be more accurate. Right? It turns out that I was wrong. The DNA may not change, but our understanding of what the DNA represents is constantly evolving. The EPD's include the most recent genomic information and are updated every Friday, but genomic scores are only updated for you to see once every year.

Kelly from American Angus explained it to me. When you run a Genomic test, the SNP’s, of that animal are compared to those from hundreds of thousands of others. Each SNP represents a difference in a single DNA building block, called a nucleotide. Scientists somehow determine that certain SNP’s are responsible for certain traits, so it is assumed if the SNP’s of a certain bull or cow are similar to those of others with a certain trait, then they will share that trait. Assumptions are not always accurate. At one time this was done manually, but now computers are able to analyze and calculate similarities by analyzing thousands of pieces of data at the same time. EPD’s are recalculated every Friday using the actual data turned in by producers and looking at the information provided through the genomic analysis. The EPD’s are always being refreshed, however the numbers you see in a genomic score are not updated until the computers make an annual run adding all of the information collected over the prior year. The genomic scores you now see on your animals when you log in to AAA were just updated May 28th, so are pretty current. Those numbers will be different than what you saw over the last year and some may change quite a bit. When you find a genomic score for an AI bull on your computer, it could be years old if the stud does not update their information. The EPDs on the other hand will have changed very little, if at all, when those genomic numbers were recalculated and reposted on the 28th.

The fact is, even though DNA doesn’t change, we are still learning what that DNA does, and original assumptions are often found to be inaccurate. If you see a genomic score on a bull that says he is in the bottom 20% for Heifer pregnancy, but his EPD puts him in the top 20%, it is because the data since that genomic score was run has changed expectations. With something like heifer pregnancy, there is less data to analyze, so these numbers are still likely to keep changing. Birth weight has more actual data and is less likely to move. Weaning weight is one that can be off in your environment. Environment plays a huge part in weaning weights, and I expect most data on this comes from purebred breeders and cows that are treated way better than the cows in the average large commercial herd. For that reason, I expect weaning weight EPDs and genomic scores should often be suspect. I, for example, have an eleven-year-old cow with a weaning weight average of 105% in my herd on 9 calves. She has a genomic score that puts her in the bottom 16% for weaning weights, but in my tougher environment she easily out weans cows with better scores. In past years her genomic score has put her as low as the bottom 1% for weaning weight.

I have found that most of the genomic scores I first received in 2015 have changed dramatically, and today's scores are definitely closer to my actual data. As an example, a bull I ran a genomic test on in 2015, had a score that put him in the bottom 15% for Birth weight and his birth weight EPD was + 3.2. I expected this based on his own performance and he was chosen as a growth bull to be used on cows. His genomic score for weaning weight put him in the top 22%. He sired about 100 calves, and we found his to be some of our smallest calves, but weaning weights were unimpressive. His genomic score now shows him in the top 9% for low birth weight and his BW EPD is at .5. His WW genomic score is now 89 and his WW EPD has dropped to 39 pounds.
Great info thank you for sharing this!
 

diana55

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Yes especially if not much data has been recorded. It is very easy to get great unproven EPD's by breeding to numbers and not recording data. In Australia we don't get to actually see the genomic results, Angus Australia controls it all and it goes straight into the bi monthly EBV calculations. I often have my suspicions that they might edit the results a bit so they don't look like goose's when their EBV's are proven incorrect. To find out the effect that genomics have on my heifer's EBV's I print out their EBV's at time of collection of hair and compare to the breedplan run when the results are in. There is never any massive change just a bit of tweaking which fuels my suspicions.

Ken
My thoughts exactly Ken. Easy to 'breed' figures, just use 2 high EBV animals. Not happy with Angus Australia and have no faith in genomics, as they are just used to tweak EBVs as you said. Just means we always have our wallet open, paying for Breedplan and genomic tests.
 

FungusProudKY31

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If EBDs and EBVs were the answer as a cure-all, they would have totally dominated the breeding programs after 5 generations to have over 96% genetic influence of the cattle. That has not panned out.

So every generation after 30 or 40 years still have to be bred to a freak or an outlier to try to up the carcass traits. And like the proverbial lemmings almost all people want to walk the same path and reach the same high ledge. Seldom do I see a picture of a "real cow" but a cow that is more steer-like in her excess muscling, weight and type. It is the expected results of one-size-fits-all and go for the terminal traits without any brakes.

The downfall of maximizing terminal traits in all cattle is the absolute need to go back to the basics and maintain cow fertility, ease of keeping and basic function to keep profitability in the cow/calf operations. The best practical opportunity is to have a well balanced and functioning cow herd and use terminal sires in spite of their looks, problems, type or breed which are true to type in the terminal traits they transmit: marbling, muscle ... That became the basic premise of the late Larry Leonhardt's advice and efforts to the beef sector. He was not accepted in his beliefs because everybody wants to have a cow herd of terminal type females rather than having a two type system.

Animal issues are usually people issues.
 

Stocker Steve

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She has a genomic score that puts her in the bottom 16% for weaning weights, but in my tougher environment she easily out weans cows with better scores. In past years her genomic score has put her as low as the bottom 1% for weaning weight.

I have found that most of the genomic scores I first received in 2015 have changed dramatically, and today's scores are definitely closer to my actual data.
How do you use genomic scores ?
 

Katpau

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In all honesty, I don't use them to select my replacements yet, but I am a numbers person (retired CPA) and I have huge quantities of actual data going back to when the first registered Angus bulls were used here in the 90"s. I find it fascinating to watch as the genomic numbers change and over time, have come closer and closer to what I am observing from the actual data I have collected.

I do demand that bulls I use in my herd have a genomics test. Now that I understand how it works, I no longer worry about seeing those numbers since they are already reflected in his EPDs. At one time I was obsessive about collecting and analyzing these numbers on AI bulls, but those numbers are no longer as readily available, and I am content to let the computers do the work. I do still keep tract of the changes in genomic numbers in my own herd.

Most reputable breeders collect and submit DNA on their sale bulls in order to increase accuracy of EPDs with a genomic profile. I feel that if you are a seed-stock producer selling registered bulls, you owe it to the registry to collect all available data including DNA and turn it in to the registry, so that the data can be used to increase the accuracy of EPDs and future genomic profiles. I know there are breeders that don't agree, and they have the right to disagree. I won't buy bulls or semen from them however.

I collect and submit DNA on my commercial cows, because I think that it is important data for AAA to have. Insufficient commercial data is probably one of the biggest weaknesses to genomics. When selecting replacements, I still prefer to select heifers based on their mothers, fathers and their own performance and phenotype. I usually select my replacements before running DNA. There may come a time when I trust the genomics enough to select replacements based on genomics, but I am not there yet. It would be an interesting experiment for me to run two herds. One would select replacement based on genomics alone, and the other would use my traditional selection process. I don't have the ability to do that, but it would be fun.

When I first started collecting genomic data, I was disappointed in how often it seemed to be wrong,. I had high hopes for it, thinking "You can't fake DNA". Now I understand, that while they may be able to recognize unique SNP's, scientists don't necessarily know what they do. As time goes on, I am finding that those genomic numbers are getting closer to my actual data. There may come a time when I test all potential heifers and select based on genomics in combination with phenotype. I'm not there yet, and that is in part because the most important traits are still not measured with those genomic scores. For me the most important one is longevity. I want a cow that calves as a 2 year old and keeps on calving every 365 days for another 10 years. I also demand good udders and there is not yet an EPD for that in the Angus breed. They say fertility is not highly heritable, but I have certainly found some lines to be less fertile than others. That may be due to defects that result in early abortion. If a cow looses her calf at 1-3 months, all you see is an open or late calving cow. I know AAA is doing some research on that. I think it would help to get more data from commercial cow/calf herds, whose primary focus is selling calves rather than expensive breeding animals.
 

Buck Randall

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In all honesty, I don't use them to select my replacements yet, but I am a numbers person (retired CPA) and I have huge quantities of actual data going back to when the first registered Angus bulls were used here in the 90"s. I find it fascinating to watch as the genomic numbers change and over time, have come closer and closer to what I am observing from the actual data I have collected.

I do demand that bulls I use in my herd have a genomics test. Now that I understand how it works, I no longer worry about seeing those numbers since they are already reflected in his EPDs. At one time I was obsessive about collecting and analyzing these numbers on AI bulls, but those numbers are no longer as readily available, and I am content to let the computers do the work. I do still keep tract of the changes in genomic numbers in my own herd.

Most reputable breeders collect and submit DNA on their sale bulls in order to increase accuracy of EPDs with a genomic profile. I feel that if you are a seed-stock producer selling registered bulls, you owe it to the registry to collect all available data including DNA and turn it in to the registry, so that the data can be used to increase the accuracy of EPDs and future genomic profiles. I know there are breeders that don't agree, and they have the right to disagree. I won't buy bulls or semen from them however.

I collect and submit DNA on my commercial cows, because I think that it is important data for AAA to have. Insufficient commercial data is probably one of the biggest weaknesses to genomics. When selecting replacements, I still prefer to select heifers based on their mothers, fathers and their own performance and phenotype. I usually select my replacements before running DNA. There may come a time when I trust the genomics enough to select replacements based on genomics, but I am not there yet. It would be an interesting experiment for me to run two herds. One would select replacement based on genomics alone, and the other would use my traditional selection process. I don't have the ability to do that, but it would be fun.

When I first started collecting genomic data, I was disappointed in how often it seemed to be wrong,. I had high hopes for it, thinking "You can't fake DNA". Now I understand, that while they may be able to recognize unique SNP's, scientists don't necessarily know what they do. As time goes on, I am finding that those genomic numbers are getting closer to my actual data. There may come a time when I test all potential heifers and select based on genomics in combination with phenotype. I'm not there yet, and that is in part because the most important traits are still not measured with those genomic scores. For me the most important one is longevity. I want a cow that calves as a 2 year old and keeps on calving every 365 days for another 10 years. I also demand good udders and there is not yet an EPD for that in the Angus breed. They say fertility is not highly heritable, but I have certainly found some lines to be less fertile than others. That may be due to defects that result in early abortion. If a cow looses her calf at 1-3 months, all you see is an open or late calving cow. I know AAA is doing some research on that. I think it would help to get more data from commercial cow/calf herds, whose primary focus is selling calves rather than expensive breeding animals.
Genomics definitely improve as the number of animals tested increases. Holstein numbers are really good, to the point that they can predict susceptibility to specific diseases.
 

J+ Cattle

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You would expect the genomic score to be more accurate, but you would be wrong. My original thoughts were…people can manipulate data, but you can’t manipulate DNA, so the genomics should be more accurate. Right? It turns out that I was wrong. The DNA may not change, but our understanding of what the DNA represents is constantly evolving. The EPD's include the most recent genomic information and are updated every Friday, but genomic scores are only updated for you to see once every year.

Kelly from American Angus explained it to me. When you run a Genomic test, the SNP’s, of that animal are compared to those from hundreds of thousands of others. Each SNP represents a difference in a single DNA building block, called a nucleotide. Scientists somehow determine that certain SNP’s are responsible for certain traits, so it is assumed if the SNP’s of a certain bull or cow are similar to those of others with a certain trait, then they will share that trait. Assumptions are not always accurate. At one time this was done manually, but now computers are able to analyze and calculate similarities by analyzing thousands of pieces of data at the same time. EPD’s are recalculated every Friday using the actual data turned in by producers and looking at the information provided through the genomic analysis. The EPD’s are always being refreshed, however the numbers you see in a genomic score are not updated until the computers make an annual run adding all of the information collected over the prior year. The genomic scores you now see on your animals when you log in to AAA were just updated May 28th, so are pretty current. Those numbers will be different than what you saw over the last year and some may change quite a bit. When you find a genomic score for an AI bull on your computer, it could be years old if the stud does not update their information. The EPDs on the other hand will have changed very little, if at all, when those genomic numbers were recalculated and reposted on the 28th.

The fact is, even though DNA doesn’t change, we are still learning what that DNA does, and original assumptions are often found to be inaccurate. If you see a genomic score on a bull that says he is in the bottom 20% for Heifer pregnancy, but his EPD puts him in the top 20%, it is because the data since that genomic score was run has changed expectations. With something like heifer pregnancy, there is less data to analyze, so these numbers are still likely to keep changing. Birth weight has more actual data and is less likely to move. Weaning weight is one that can be off in your environment. Environment plays a huge part in weaning weights, and I expect most data on this comes from purebred breeders and cows that are treated way better than the cows in the average large commercial herd. For that reason, I expect weaning weight EPDs and genomic scores should often be suspect. I, for example, have an eleven-year-old cow with a weaning weight average of 105% in my herd on 9 calves. She has a genomic score that puts her in the bottom 16% for weaning weights, but in my tougher environment she easily out weans cows with better scores. In past years her genomic score has put her as low as the bottom 1% for weaning weight.

I have found that most of the genomic scores I first received in 2015 have changed dramatically, and today's scores are definitely closer to my actual data. As an example, a bull I ran a genomic test on in 2015, had a score that put him in the bottom 15% for Birth weight and his birth weight EPD was + 3.2. I expected this based on his own performance and he was chosen as a growth bull to be used on cows. His genomic score for weaning weight put him in the top 22%. He sired about 100 calves, and we found his to be some of our smallest calves, but weaning weights were unimpressive. His genomic score now shows him in the top 9% for low birth weight and his BW EPD is at .5. His WW genomic score is now 89 and his WW EPD has dropped to 39 pounds.
This has been especially frustrating for m, I paid for the test and their expertise in evaluating the data so I could make informed decisions. My scores are changing dramatically from 6 months ago. What was so bad genetically that I culled is now showing up as some of my best animals. If I can’t trust the results then why should I do DNA testing?

J+ Cattle
 

Wind and Sage

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You would expect the genomic score to be more accurate, but you would be wrong. My original thoughts were…people can manipulate data, but you can’t manipulate DNA, so the genomics should be more accurate. Right? It turns out that I was wrong. The DNA may not change, but our understanding of what the DNA represents is constantly evolving. The EPD's include the most recent genomic information and are updated every Friday, but genomic scores are only updated for you to see once every year.

Kelly from American Angus explained it to me. When you run a Genomic test, the SNP’s, of that animal are compared to those from hundreds of thousands of others. Each SNP represents a difference in a single DNA building block, called a nucleotide. Scientists somehow determine that certain SNP’s are responsible for certain traits, so it is assumed if the SNP’s of a certain bull or cow are similar to those of others with a certain trait, then they will share that trait. Assumptions are not always accurate. At one time this was done manually, but now computers are able to analyze and calculate similarities by analyzing thousands of pieces of data at the same time. EPD’s are recalculated every Friday using the actual data turned in by producers and looking at the information provided through the genomic analysis. The EPD’s are always being refreshed, however the numbers you see in a genomic score are not updated until the computers make an annual run adding all of the information collected over the prior year. The genomic scores you now see on your animals when you log in to AAA were just updated May 28th, so are pretty current. Those numbers will be different than what you saw over the last year and some may change quite a bit. When you find a genomic score for an AI bull on your computer, it could be years old if the stud does not update their information. The EPDs on the other hand will have changed very little, if at all, when those genomic numbers were recalculated and reposted on the 28th.

The fact is, even though DNA doesn’t change, we are still learning what that DNA does, and original assumptions are often found to be inaccurate. If you see a genomic score on a bull that says he is in the bottom 20% for Heifer pregnancy, but his EPD puts him in the top 20%, it is because the data since that genomic score was run has changed expectations. With something like heifer pregnancy, there is less data to analyze, so these numbers are still likely to keep changing. Birth weight has more actual data and is less likely to move. Weaning weight is one that can be off in your environment. Environment plays a huge part in weaning weights, and I expect most data on this comes from purebred breeders and cows that are treated way better than the cows in the average large commercial herd. For that reason, I expect weaning weight EPDs and genomic scores should often be suspect. I, for example, have an eleven-year-old cow with a weaning weight average of 105% in my herd on 9 calves. She has a genomic score that puts her in the bottom 16% for weaning weights, but in my tougher environment she easily out weans cows with better scores. In past years her genomic score has put her as low as the bottom 1% for weaning weight.

I have found that most of the genomic scores I first received in 2015 have changed dramatically, and today's scores are definitely closer to my actual data. As an example, a bull I ran a genomic test on in 2015, had a score that put him in the bottom 15% for Birth weight and his birth weight EPD was + 3.2. I expected this based on his own performance and he was chosen as a growth bull to be used on cows. His genomic score for weaning weight put him in the top 22%. He sired about 100 calves, and we found his to be some of our smallest calves, but weaning weights were unimpressive. His genomic score now shows him in the top 9% for low birth weight and his BW EPD is at .5. His WW genomic score is now 89 and his WW EPD has dropped to 39 pounds.
I think breeding strictly by numbers, whether EPD or genomic, can be very over rated, can sometimes be misleading, and many times are used too much as a marketing tool rather than a selection tool. I also appreciate the observation of environment. I've seen good cattle that work in a certain environment that simply fall apart in the high desert of Wyoming. I could go on for a long time on a few more points, but I need to go check stock water, which is very sparse in this country.
 

Nkline

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It is not always easy to get the genomic scores when selecting bulls to use and often i will see that a genomic score will contradict an EPD. Like an HP epd of 12 and a genomic score of 80. I feel like if they are scoring well for a genomic trait then I should trust that more than an EPD. Am I wrong for thinking this way? I mean isn't DNA more proof of what might be passed on?
HP is tricky, as sometimes the fattest heifer in the pen will have problems getting pregnant. If the fattest heifer in the pen was the norm and they were fed accordingly would you have pregnancy issues? For HP I try to stay away from lines with know problems, and outlier low scoring bulls. Genomics are getting better, but have a hard time finding unique gene variants that may be superior. So low usage pedigrees have a real possibility of being misrepresented by both Epds and genomics.
 

elkwc

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You would expect the genomic score to be more accurate, but you would be wrong. My original thoughts were…people can manipulate data, but you can’t manipulate DNA, so the genomics should be more accurate. Right? It turns out that I was wrong. The DNA may not change, but our understanding of what the DNA represents is constantly evolving. The EPD's include the most recent genomic information and are updated every Friday, but genomic scores are only updated for you to see once every year.

Kelly from American Angus explained it to me. When you run a Genomic test, the SNP’s, of that animal are compared to those from hundreds of thousands of others. Each SNP represents a difference in a single DNA building block, called a nucleotide. Scientists somehow determine that certain SNP’s are responsible for certain traits, so it is assumed if the SNP’s of a certain bull or cow are similar to those of others with a certain trait, then they will share that trait. Assumptions are not always accurate. At one time this was done manually, but now computers are able to analyze and calculate similarities by analyzing thousands of pieces of data at the same time. EPD’s are recalculated every Friday using the actual data turned in by producers and looking at the information provided through the genomic analysis. The EPD’s are always being refreshed, however the numbers you see in a genomic score are not updated until the computers make an annual run adding all of the information collected over the prior year. The genomic scores you now see on your animals when you log in to AAA were just updated May 28th, so are pretty current. Those numbers will be different than what you saw over the last year and some may change quite a bit. When you find a genomic score for an AI bull on your computer, it could be years old if the stud does not update their information. The EPDs on the other hand will have changed very little, if at all, when those genomic numbers were recalculated and reposted on the 28th.

The fact is, even though DNA doesn’t change, we are still learning what that DNA does, and original assumptions are often found to be inaccurate. If you see a genomic score on a bull that says he is in the bottom 20% for Heifer pregnancy, but his EPD puts him in the top 20%, it is because the data since that genomic score was run has changed expectations. With something like heifer pregnancy, there is less data to analyze, so these numbers are still likely to keep changing. Birth weight has more actual data and is less likely to move. Weaning weight is one that can be off in your environment. Environment plays a huge part in weaning weights, and I expect most data on this comes from purebred breeders and cows that are treated way better than the cows in the average large commercial herd. For that reason, I expect weaning weight EPDs and genomic scores should often be suspect. I, for example, have an eleven-year-old cow with a weaning weight average of 105% in my herd on 9 calves. She has a genomic score that puts her in the bottom 16% for weaning weights, but in my tougher environment she easily out weans cows with better scores. In past years her genomic score has put her as low as the bottom 1% for weaning weight.

I have found that most of the genomic scores I first received in 2015 have changed dramatically, and today's scores are definitely closer to my actual data. As an example, a bull I ran a genomic test on in 2015, had a score that put him in the bottom 15% for Birth weight and his birth weight EPD was + 3.2. I expected this based on his own performance and he was chosen as a growth bull to be used on cows. His genomic score for weaning weight put him in the top 22%. He sired about 100 calves, and we found his to be some of our smallest calves, but weaning weights were unimpressive. His genomic score now shows him in the top 9% for low birth weight and his BW EPD is at .5. His WW genomic score is now 89 and his WW EPD has dropped to 39 pounds.
Katpau as a commercial breeder I have found both to be of little if any benefit in bull selection. You mention BW. I have found both to be very misleading in BW also. Just this year I have talked to 3 breeders who used the same bull on heifers. He had good BW numbers both on genomics and EPD's. All 3 breeders had a wreck on the heifers they used him on although their heifers bred to other sires calved fine.His BW EPD dropped to a 6 I think. I have went back to only using a bull on heifers that has at least one calf crop on the ground and preferably 2. I select a bull by actual numbers, measurements and type. The low accuracy EPD's and genomics don't work for us.
 

Stocker Steve

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This has been especially frustrating for m, I paid for the test and their expertise in evaluating the data so I could make informed decisions. My scores are changing dramatically from 6 months ago. What was so bad genetically that I culled is now showing up as some of my best animals. If I can’t trust the results then why should I do DNA testing?

J+ Cattle
Maybe the scores were right the first time ?
 

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