Episode 06 (Season 03) - Genomic vs. Daughter-proven Bulls - What Are Their Merits?

Daughter-proven bulls have been a staple in cattle breeding for generations; they have bred many world-class bloodlines. However, with technological development, more reliable tools have become available. Today, more and more farmers use genomic solutions to fully understand their herd’s potential.

So, is this why farmers are transitioning away from daughter-proven bulls toward genomic sires? And do these bulls differ in their breeding values and roles in cattle breeding?

To take a deep dive into the cattle breeding of yesterday, today, and tomorrow, we invited a dairy farmer and a genetics expert to share their knowledge and experiences with breeding bulls.

Guests:
Casper Koldkjær Pedersen, Owner and Manager at Tronsmark Holstein, Denmark
Lars Nielsen, Chief Breeding & Production Officer at VikingGenetics

Host: 
Tomás De La Rosa

Transcript

0:11

Daughter proven bulls have been a staple in cattle breeding for generations. They have bred many world class bloodlines. However, with tech advancements, more reliable tools have become available. Today, more and more farmers use genomic solutions to fully understand their herd’s potential. So is this why farmers are moving away from daughter proven bulls towards genomic sires? And do these bulls differ in their breeding values and roles in cattle breeding? To take a deep dive into the cattle breeding of yesterday, today and tomorrow, we invited a dairy farmer and a genetics expert to share their knowledge and experiences with breeding bulls. Casper Koldkjær Pedersen, owner and manager at Tronsmark Holstein in Denmark, and Lars Nielsen, Chief Breeding and Production Officer at VikingGenetics. This is the BreedCast produced by VikingGenetics. I'm your host, Tomás De La Rosa. Hello and welcome, Casper and Lars, thanks for joining us today. Yeah. Thank you. Thank you. Casper, you have been involved with cattle breeding all your life. Some might even say you grew up at livestock shows. Can you tell us a little bit about your experience? I guess that's a bit of an overexaggeration, but, yes, I've grown up on a typical Danish dairy farm. Back then we had 50 cows, which was close to average back then. And, today we are around 200 cows, which is a little below average in Denmark today. So what I would call a typical family farm, I think around the breeding, it's always been a family passion. So, I've inherited it from my father, and it's been as subjects we've been talking about all the time since I grew up. It's a passion. I think, also, a tendency that in the family we've been a bit of nerds around it looking into details and, yeah, again, this passion has been a big part of the daily talks, back when I was a kid and growing up. And, I would say today it's maybe much more business. To be honest, I don't spend a lot of energy on cattle shows anymore or breeding cows for cattle shows. I need cows that pay the bills. So, that's my focus, and you could say it's not about how these cows look, it's more about how they cook. You need cows that really perform well and use the resources. And again, that talks into the agenda, which is important for dairy farmers today, the climate impact, all the new agendas around us and the demands from society. And when it comes to the passion and passion for breeding the man next to you, Lars Nielsen, he's also very passionate about breeding. Let's start by discussing why daughter proven bulls have become so, or have historically been so reliable for farmers. Why have they had such an essential role in establishing the bloodlines we know today? If you can start, Lars? You can say making daughter proven bulls was a huge, improvement compared to what we did in the early days with breeding, where you did look at the conformation of a certain bull, if he was good looking, he was used a lot. People realized that that might not be the best way because the daughters didn't always look like the sire. Then we started up with test stations, where a group of a certain bull were placed. but anyway, we did have quite some problems because it was more a competition of... Well, you can say between managers, when you were comparing production ability of certain bulls across the stations, because at that time we were not able to remove the environmental impact with different management levels. So then we started actually to do this test of bulls in the normal environment or normal dairy farms, making more sophisticated genetic evaluation models where we try to remove the, you can say, environmental and managerial impact and try to keep what is just the genetics. And we have done that quite well. Production, conformation are quite easy to do more or less in all systems worldwide. In the Nordic countries, we have been very good to also implement, health and fertility traits, with big daughter groups with reliable registrations. And for that reason, we ended up to have really high, and still do have on our daughter groups, high reliability on all traits. So you can say, you know what you get when you use a daughter proven bull. You have a very high reliability. And for that reason, it was a huge, huge step forward when we implemented what we at that time called the modern breeding scheme with daughter proofs. Casper? Yeah, you could say also when you when you ask how it historically was which role it has today... Back in the 90s and early 20s there was a lot of... or there was not a lot of sires of sons on a global level. Actually, we used a lot of the same bloodlines. So, today what we see is, we do not have the variety as we could have had because of how we used sires of sons 20, 30 years ago. And, so for that reason, these bulls had a huge impact back then. And globally, we have, at least within the Holstein breed there's not so much variety. I think we've broadened it up. And with genomic selection, it has given us a tool that's given us better variety of genetics today than we had 10-20 years ago. In what aspects, do daughter proven bulls outperform their genomic counterparts? You can say, in general reliability, the daughter proven bulls are in general more reliable than the genomic bulls. That's how it is. So if you really want to know what you get, you should use a daughter proven bull with high reliability. Some farmers are looking where the most important thing is mostly to have a very homogene herd from a conformation point of view. There's no doubt that a daughter proven bull might give you a more homogene herd, but in my point of view, you lose too much in the general genetic improvement by taking that aspect in. You could add to that what is a daughter proven bull? Because when a bull has a daughter group, which is, 100 days within the first lactation, you do a lot of prediction on the few data that you have through these hundred days. And, there you will have a much lower reliability on some of the traits. And, there's a big difference between how a daughter would perform in first lactation compared with second, third and fourth lactation and even longer. And what we aim for today is to have long lasting cows, cows that milk for four, five, six years. so again, if you call a bull a daughter proven bull based on 100-200 days of lactation in the first lactation and then predict from then on, you will have a lower reliability than what you get from a genomic prediction. On some traits it might be a little higher, but on many traits it will be lower. And again, historically when we worked with daughter proven bulls, we often tended to jump into the new star. But those figures were based on too little reliability. And we learned a lot from using these top daughter proven bulls and then finding out years later that they didn't perform as it was predicted due to the fact that the prediction was only on 100-200 days in first lactation of the daughter group, and that was a challenge and a problem back then. We didn't acknowledge at the time we worked with it. We only had the focus for the new bull. But seen when we look back in history, that was a problem. And we used some bulls that we shouldn't have used. And again, we do not want to breed for cows that perform well in first lactation only. We need cows that last long. Again, at least five or six lactations. That is much better for the farm economy. It's much easier to work with. And it's a lot better for society in terms of climate impact. And this is where genomic testing comes in, because ultimately that's what takes away some of that guessing work. Lars, how has genomic testing transformed cattle breeding, especially in terms of making genetic progress faster? You can say the results from a genomic test they can appear as fast as if we take the DNA. And as fast as we are able to do the genetic evaluation. So in principle, in a few days. So whenever a calf is born, within a few weeks, we are able to know whether it's for breeding or it's for beef, or as a slaughter calf. so for that reason, we have the opportunity to make much faster decisions. Earlier, when we used the daughter proven bulls, they were five years, six years old when we used them as sires of sons. Today, we start to use the bulls when they are producing the first semen. Today, we are even making embryos from fresh semen from very young bulls, where we are still not able to freeze the semen. So sometimes they are 11 months old when we make the first inseminations for embryo production. The second part, that's the female side, because to make a reliable product, to lower the risk, we were using a huge part of older cows, or at least lactating cows, where we did know the genetic level of the sire. So the sire had already other daughters. So we are not guessing too much. So quite often, you can say, it was three-year old cows we did use as dams for next generation. Today we are starting to make embryos on heifers being eight months old. When we use IVF, a little older, than when we use normal flushing. So we have really reduced the generational interval. So everything has been speeded up. And we can say by discussing your question before about the daughter proven bulls. Of course, when doing this, there will be some disadvantages that some of these will also do some reranking, but the ones where everything go well and we combine the good females with the good bulls, we are really speeding up in a very, very big speed. And Casper, how do you use genomic testing in your herd? Yeah, I guess from Lars' perspective, it's a lot about breeding the top bulls. On a farm level, my main purpose in using genomic selection is to breed a good herd of cows that can perform well and give me good farm economy and use the resources available on the farm as best as possible. We test all the heifers when we put in the ear tag. So, from day one, we do the sample of the DNA, and then, yeah, I actually don't need a result before they are more than half a year, the heifers, because the decision point, I will have... We’ll take a decision based on the DNA. That will be when I inseminate the heifers. And then, yeah, we test all our females. We use sexed semen on the young animals and the high-ranking females. And then we use a lot of beef semen on our older cows, and they are still good, strong, old cows. And they will be able to milk for many years. But we do not need the next generation from them because we already have one or two heifer cows from the good, older cows, and then we use the next generation. So, yeah, it's been speeded up a lot for the last 20 years with the genomic selection. And some farmers would argue that it's difficult to believe in. They would rather want to look at their cows and then take a decision based on what they see. And here you need to put a bit of trust into the system. But, I think this is based on data from my own farm and from my colleagues’ farms, this reference population behind the calculations. And, I have a big trust in the setup we have here in Denmark. All farms that are participating are delivering data. So, again, everything is being revealed about the daughter groups and it's being put into the reference population. And from that population, then we calculate the new genomic breeding values. And what I hear from my colleagues is that, again, this is an on farm management tool today, just as much as it's a breeding tool. We previously spoke about the reliability of daughter proven bulls and some of the guesswork involved with them. And genomic testing obviously takes that away. Are there any scenarios where genomic bulls are more reliable than daughter proven ones? Yeah, there is, for sure. Point one in some of our breeds, Holstein, it's a quite international breed. We have always known that we are not just a Nordic protected area here. We are using international genetics. Earlier, we also did use sires of sons from international partners being daughter proven. But we always did have problems with what we call the more Nordic traits; general health, mastitis resistance, youngstock survival for example. And now also the Saved Feed area where we didn't know much. It was a kind of an unknown lottery ticket in those areas, even though we have used daughter proven bulls. By doing genomic testing today, we do have, quite reliable knowledge about those traits when we come to genetics in general, it's no doubt that new bulls, genomic proven bulls will have higher reliability on some of the traits we are talking about here; saved feed, methane emission, due to a very, you can say, a strong reference group. So genomics here are able to really give us good knowledge, on an early level that we would not be able to do in daughter proof because it will just be a few daughters from each bull having CFIT, you can say, feed intake registrations, on individual level. So the reliability on those traits on daughter proven bulls would be too low if we didn't implement genomic information. Casper. Yeah, I think, to support what Lars is saying here, and maybe adding to that that again what I said earlier, the daughter proven bulls... again you will not have high reliability in the first year with the daughter group. And, we have had a lot of examples on bulls, genomic bulls, top bulls we've used. And when they get the first daughter proof, they tend to drop. But then again, after a year, two years, when the daughter group has performed through a number of lactations, they come back. A bull like in Holstein, like VH Brixton, which is a top Holstein bull for his generation. He started out pretty low on his daughter proof. And again, that is because the daughter proof in the beginning does not have as high reliability as a genomic proof. And, I hope it will be more and more implemented that it is a mix of genomic information and daughter proof, especially in the beginning of a daughter group's performance. Because we need the cows that milk for, again, four, five, six years on a top level, and not just the ones that milk well in the first lactation and then burn out. I'm really glad that you brought up the example of VH Brixton because one thing that I'd like to discuss is what is the best breeding policy in sire selection for dairy farmers to use? Because some might use a few daughter proven bulls and mass. Whereas nowadays you can use a team of genomic sires. What is the best strategy to use? On farm level, it's both. It's always been the general policy that we've used. But I've learned it the hard way that you need to spread out, you need to use a number of bulls. And there's not just one star. And all the bulls made available in a breeding program are top bulls. So, again, use what's available and then do the right mating between the females you have on farm and then the bulls that are available from a technician. And of course I think it's important that you herd by herd take the individual choice which kind of cow do you want to produce. So you among the big list and the many lottery tickets or the many bulls, we have in the bull portfolio here, select or make the frames. What's important for me? Is it to make udders fitted for robots? Do you have challenges with mastitis resistance or other single traits, make the frame and then just use, like Casper says, a huge variation of the bulls living up to those criteria. That's no doubt. And you can say what we sometimes hear is that some farmers

say, like you introduced Tomás: 20:34

I want to use the daughter proven bulls to have a more homogene herd. But that's only when you look at the conformation. and by doing that, you are making a lot of compromises with the genetic progress in general. And genetic progress that equal to economy, and for that reason, I will not recommend that part. But of course, it's up to the individual farmer to decide on his or her preferences. And with all this talk about breeding for the future and the healthier cows that we ultimately want to get, we have a lot of resources, both on our website and on the BreedCast. If our listeners want to learn more about how cattle breeding might look in the future, specifically in the year 2040, we have an episode of the BreedCast on the subject. It features Lars and an award winning agri journalist from Northern Ireland discussing the future of dairy farming. And I think our listeners should definitely check it out. We've heard about the historic importance of daughter proven bulls and the rise of genomic sires over the last few years. Now, Casper, I'd like to tap into your experience in farming to give our listeners some insights about the decision making in breeding values. Let's start by discussing why are breeding value so important for sire selection, and how does reliability factor in? I guess, it is the best available tool to choose the right bull for the individual cow that you want to inseminate and make pregnant. And again, I think, we need to look back in history. But yeah, some farmers still today tend to look a lot on the type traits. Again, what you see is what you believe in, but this system is backed up by so much data, which comes from all the farms, from my farm, from all my colleagues’ farms here in Denmark, in the Nordic countries. So it is an intelligent choice in my mind. It's a scientific based set up and, yeah, I think it's very easy for me to choose to use the breeding evaluation and the estimates on each bull. And then again, when we talk about reliability, this is not 100% right answer, you get on an individual bull and on the individual traits of the bull and, yeah, again you need to just work with it. Not with your emotions, but just from a fact based approach, and then do the right matings. And again, it will not be 100% perfect. but it is by far the best tool that is available, for doing the right management decisions. Lars? I can just support what Casper is saying. I have no doubt. I will always recommend the farmers to do a genomic test in the herd, both for finding the dams for next generation, but also to make the best possible combinations. Of course, it should be used as a decision tool. Because if you are not using sexed semen and beef, or just sexed female semen on the best animals, then you don't get enough out of it. But we do see the general trend is that more or less all dairy farmers are using that in the daily management. Casper, as a dairy farmer and specifically a farmer in Denmark production on health in a balanced focus are the two things you really care about in your dairy herd. Currently, your farm's output is just about 14,000 kilos of energy corrected milk per cow. Can you tell the listeners how you look at breeding values when making some decisions about this? What are your focuses? Yeah. yeah. You mentioned production and health and that's for sure two of the important areas. But there's one thing that comes first and it's for all species. You need fertility in order to survive. And I guess we just take that for granted. Within the Holstein breed, we have had, now some years back, but we had too low fertility, and that is a challenge as a dairy farmer. You need strong fertility in your herd. And then, I use the Nordic Total Merit index. The NTM. Because, again, it's based on data from my colleagues’ and my own farm. I trust that a lot. And then I use the genomic selection. Again, I test all my heifers and use sexed semen on the best animals and a lot of beef semen to make the best waste product, you could say. Each cow needs to have a calf. Maybe not every year, but almost every year. But we do not need all these being... I do not have any special preferences. I use the Total Merit index as the main guideline, but in the mating program, we of course put attention to the traits that are important in the farm that I have, the environment that I have, and we milk with Lely robots. So we have, for many years now, put a little more attention to the traits like teat placement and balance of the udder, milkability, traits like that. But it's not a big focus today. Bulls that are available are already selected, on minimum selection for all traits, actually. So, that is not a problem today and I do not have any, problems in my herd in terms of being milked by the robot of having a function, I think. I have a little older barn, and I think the main challenge would be the size of the cows that they are actually becoming too big. Thank you for joining us on the BreedCast today. We've discussed the historic importance of daughter proven bulls and the rise of genomic tested animals. We also discussed how you can make more informed genetic decisions. If you want to learn more about VikingGenetics, our dairy and beef breeds, get tips and tricks for breeding and management, and much more, please visit our website; VikingGenetics.com. Huge thanks to Casper Pedersen and Lars Nielsen for sharing their insights. A huge shout out to all of our listeners. If you have an idea for a topic in the world of dairy farming and cattle breeding you would like us to focus on, please visit BreedCast.com or message us on the VikingGenetics Facebook or Instagram pages. You've been listening to the BreedCast- Innovative breeding in your ears. I'm your host, Tomás De La Rosa. Please join me in the next episode where we will discuss the role of VikingJersey cows in cheese and ice cream production in the United States.