Raising the steaks – the science of cattle breeding.


Raising the Steaks, The Science of Cattle Breeding. How many calves would you guess one cow can have in her lifetime? Three, eight, twenty seven point three nine five two? For the cow they call W449 the answer is a massive one hundred and thirty seven calves. How’s this even possible? Is she some kind of super cow? W449, you could say is she a super cow, a good cow or what she is. She’s actually for a time she was almost a freakish animal. She had moderate to low birth weight and was quite muscly and then had terrific carcase attributes. And that was probably the combination of all those: moderate frame, low birth weight, reasonable growth and really good carcase attributes. There’s a reason why we use that cow in embryo transfer. And sure if she was a bull you would have been able to use the genes a lot more. But we’ve used a couple of sons of hers and I think we’ve used them extensively in our herd and we’ve sold ten thousand straws out of those bulls and they’ve worked really well in the industry, in the commercial industry. Embryo transfer is a tool we use here on our farm to multiply superior genetics throughout the herd. So, the processes are reasonably complex but the donor cows will be selected because of their performance and they’re given hormones which make them super ovulate. So, this means that they’ll release multiple eggs instead of just one or two eggs. I mean that’s where a cow like that has a lot to contribute to the beef industry because she’s actually taken it to another level. And in our herd it’s probably had a huge influence on our herd. So, whether or not you call her a great cow, a super cow or whatever, she’s actually quite a unique animal. She’s been a really game changing cow really and changed not just in our herd but all the people that have bought bulls out of and used semen out of her made a lot of difference. And in a package that’s actually sustainable you know the cows I mean, Angus cattle are renowned for high quality meat and she’s an animal that takes that to another level. And because she’s sort of more moderate frame fits into the grass fed, high marbling sort of type of meat or that the consumers are starting to like. So, yeah she’s a bit of a game changer, yeah and that’s probably why we use the cow so much. Humans have domesticated cattle for more than ten thousand years. And with a quarter of all the world’s meat coming from them, breeding is a massive industry. For most of our history striking the best genetic balance was a slow, trial and error process. But in the past few years huge advances in technology have allowed farmers to take advantage of female traits, not just bulls. This is how a super cow like W449 is able to produce so many offspring in so little time. Well, I’m a regular customer of Rennylea and I have been for about almost as long as they’ve had sales. And I guess the first thing you do when you’re buying bulls is you try and select a supplier who philosophically agrees with what you’re trying to do within your herd. And we basically are very much in sync with what Bryan and Lucinda Corrigan are doing here at Rennylea, they’re very much about using genetics to produce a regular consistent product which we can then obviously sell to the market. Well, we’re a commercial operation, so the first thing that we look for is, we want to put a calf on the ground and that is the most important commercial consideration that we would consider. And so birth weight is very important and they look here at controlling the birth weight and producing very maternal cattle. We try and buy a bull that’s got some growth as well. So, we were looking for a bull with low birth weight as well as having a thing called a ‘growth bender’ which is quite difficult to source but they have them here and they have them in abundance. And then what we call the ‘free traits’, so that’s a free trait, low birth weight, high growth rate, if you can produce it, marbling, things such as that and fertility. Again, it comes down to producing a calf on the ground and marbling’s probably the least important thing from our point of view but it is chased by the feed lotter. And it’s something that they’ve got the highest marbling herd in the country. So, yeah those are the big things which we chase. Look, J1081 has a slight outcross sire and I was looking for something a little bit as an outcross but on the maternal side they have a very, very … W449 is one of the top production cows in the herd. So, we’re basically getting a very strong Rennylea on the maternal side with a slight outcross because we are very strongly Rennylea and we just want to try and get something a bit out. He also had all the figures we wanted. He was low birth weight, high growth rate and very good marbling so he suited the bill perfectly. I was very happy to get him actually for what we got him for on the day. I guess traditionally when people go to bull sales or buy bulls, they think about the steer progeny and what they need to top the market, all those sorts of things. And I suppose in our program it’s always been developed about the fact that steers are important but more important are female cattle because female cattle eat or consume seventy percent of the grass or dry matter that’s grown on the property. So, if you’ve got a cow herd of one hundred cows or a thousand cows, whatever the size it is. Cattle eat grass and that’s what’s put weight on them and that’s what makes the money really, the weight. What you want is cows that are more moderate in size so they consume the grass more efficiently but they still need to produce calves that actually fit the market place. So, if you look at the progeny of the cow we’ve been talking about, W449 in particular, we’ve had a bull tested through a progeny test, one of her sons called Rennylea C511 and C511 is an example of a bull who has a great carcase package. He’s got a moderate maturity pattern and so he meets the aims of the consumer but he also produces daughters who are pretty efficient in our production environment. And that’s why that bull has been used widely in the industry. I’ve come from New Crown Station which is on the Northern Territory-South Australian border and it’s probably a bit over two thousand kilometres. We think that they’re probably the leaders in focusing on the female fertility side of things and that’s paramount in our herd. And we’re more focused on probably trying to breed a female that’s going to survive in our harsh conditions up there rather than looking at the steer side. And we think Rennylea’s better at that than most. Discovering a super cow is all well and good but cattle breeders can’t afford to wait for lightning to strike each time. They have to be prepared to capture that lightning in a bottle which is why the science is really important. If you use a cow like W449, I mean she’s just worked really well. And I suppose and the result and progeny have been good for the commercial industry because they’ve done all the basics right but she’s had a lot of really good, high quality carcase information on her and that’s going to only enhance meat quality which flows around to the everyday consumer. Measuring specific traits is the basis of estimating an animal’s breeding value. This starter helps the producer make informed decisions about hooking up potential sires and dams. The Estimated Breeding Value or EBV is expressed as the difference between an individual animal’s genetics and the genetic base it’s been compared to. This genetic base is usually the historic group of the particular breed. If a cow has a positive EBV in a given trait, it means she’s above average. She’s superior to the genetic base for her breed in that trait. So, breed plan calculates what we call EBVs or Estimated Breeding Values. By definition an EBV is an estimate of the animal’s genetic merit for a range of economically important traits. Producers use those estimates or breeding values on animals to select animals which are going to deliver more profitable genetics to the beef supplier chain. Every calf on this farm is caught and tagged and weighed within twenty four hours after it’s born. So, each calf is given a management ID. It has its sire and dam so we can identify by who it is. We also record the sex of the calf and the birth weight. So, the birth weight data is submitted into the National Genetic Database which is called ‘BREEDPLAN’ and this information is used to predict the breeding value of that animal for birth weight. So, the other traits that we collect throughout the calf’s lifetime, we collect growth traits and fertility traits and carcase traits as well. So, for the growth traits we will measure their two hundred, four hundred and six hundred day weights. And every cow will have a mature cow weight taken every year. To measure carcase traits we ultrasound every animal at four hundred days for intramuscular fat, eye muscle area and rib and rump fat. And for fertility traits we measure scrotal circumference in bulls and in cows we measure calving ease and gestation length. So, all of this information is submitted to BREEDPLAN to generate Estimated Breeding Values on that animal. So, traditionally when selecting animals there’s been several things the producers have been able to do. First of all they have been able to just visually assess and look at an animal. That had a number of limitations potentially there are a lot of traits which we can’t see in an animal which have quite a lot of economic consequences. So, a lot of traits relating to eating quality for instance for the consumer such as marbling gets very difficult to go through and actually see that animal visually. So, when we present these bulls for sale they have even in fact been scanned for intramuscular fat. Intramuscular fat is the trait of the animal in eye muscle and it’s measured with an ultrasound scanning machine just the same technology that’s used for diagnosing female pregnancy and so on. So, very similar sorts of technology and that was developed and collaborated for marbling in the carcase and then collaborated back to the live animal. So, in fact we can do these measurements on a live animal and we get a figure called an Estimated Breeding Value for marbling and that relates to the figure in the carcase. It has a correlation of about point seven. So, it’s a pretty good correlation in terms of selecting from approved meat quality. So, now we can select for improved tenderness, juiciness and flavour and we can meet the high quality demands of the modern consumer. So, that’s been a really exciting change over the last two decades. These calves here today, their birth weight, that data will be sent to BREEDPLAN and together with information from their sire and dam will be used to give them a breeding value for birth weight. This information can then be used as a tool by our clients when we’re marketing bulls. So, if a farmer comes in and he’s looking to buy a bull that he wants to join to his heifers, his first calf heifers then he’d look to select a bull that had a low birth weight. And this would hopefully minimise any calving problems. Within a breeding program to maximise the amount of genetic improvement we’re trying to first of all identify the animals with the superior genetics which is where BREEDPLAN and EBVs play a role. But then we’re also trying to disseminate or use those superior genetics as widely as possible within our breeding programs. And there’s a range of different technologies which are available, artificial insemination has been around a while and that enables us to really disseminate the genetics of males. But there are also now some reproductive technologies which allow us to get greater use of superior females and their genetics within the breeding program. Gathering all this data is one thing but taking advantage of it is another. Artificial insemination has been used for decades facilitating the spread of male genetic material across the world. But now cattle breeders can do the same with females thanks to embryo transfer. So, things like ET or what we call Embryo Transfer which now enables us to go out and produce more progeny from a female than would or offspring from a female than would be achievable under normal, natural mating practices. So, there are now also a range of other technologies or new technologies which enable us to take artificial insemination and embryo transfer to the next level. And particularly to get greater use out of the female genetics or superior female genetics which are available. So these are things like JIVET or Juvenile in vitro Embryo Transfer which enables us to go and get the eggs out of a very young animal before it’s hit reproductive maturity and start to breed from that animal. So, we shorten our generation time and get more profitable genetics into the system far earlier. To recap Embryo Transfer is a process that allows the genetic material from superior females to be multiplied and used by producers to lift the genetic potential of their herds more quickly than if only single natural births occurred. Donor females are those with positive EBV’s for the traits deemed important by a particular producer. Recipient females in general are those females with no particular genetic potential but are healthy, able to raise a calf and at the same stage of the reproductive cycle as the donor females. Yeah, I suppose any technology like AI and ET, I mean it’s only as good as the progeny that comes from it. And I suppose the advantage of objective measurement in beef cattle is that you’ve got something to help you make those decisions in picking the cow to do ET or the bull that you’re doing AI. I mean if you’re just looking at the animal without any data on it, it’s a bit like going into a pantry and if your pantry’s full of tins of food and they’ve got no labels on them and how do you know whether you’ve got tuna or beetroot or some other thing? The process is that we flush fertilised eggs out of donor cows and then implant them into recipient cows and these cows will then have a calf by another cow and raise that calf. So, after they’ve come onto heat the donor cows are then artificially inseminated. Seven days later we’ll have Embryo Transfer vets, they come in and they will flush the embryos out of the donor cows and then look at these embryos under a microscope and pick out all the fertilised embryos. At this point the eggs can either be frozen or they can be implanted directly into recipient cows. So, to prepare the recipient cows they have also been heat synchronised and they will have eggs implanted into them at seven days after they have cycled. So, we put fresh or frozen eggs into them after they’ve cycled. And then after about six weeks they’re pre-tested by ultrasound. And we generally get between seventy five and eighty five percent of these recipient cows in calf. Timing is extremely important in an Embryo Transfer Program. Both donor and recipient cows have to have their cycles synchronised with hormones so the embryos will have the best chance of survival. The detection of heat is essential so that cows can be artificially inseminated at the most appropriate time and flushing of embryos must be completed with care and efficiency so that the highest chance of success is possible. So, as part of an Embryo Transfer Program, estrous is synchronised in the recipient cows. We do this to ensure that the cows are in their correct stage of their cycle when we implant the embryos into them. So, this gives them a good chance of maintaining the pregnancy. So, what we’ve seen today, the cows have come into the yards and we’ve then taken the calves off them. We then run the cows up and into the race. Each cow has their electronic tag scanned. This gives you an individual record of every cow that’s gone through the Estrous Synchronisation process. After the cow’s been scanned they are then given an injection into the muscle with the hormone. Once they’ve received this injection they then go up into the crush. And when they’re in the crush they’re restrained in the head bail so that we’re able to insert a device known as a CIDR into their vaginas. So, these CIDRs release another hormone called progesterone. The CIDRs are loaded into a special gun. This gun is then dipped into lubricant and someone then is able to implant the CIDR into the cow’s vagina. Between each CIDR insertion the loading gun is washed in an antiseptic solution. So, this just ensures that the cows don’t get any infections. So, once that’s happened the cows are then let out of the crush and they’re put back with their calves and then they’ll go back out into the paddocks. So, we’ve really nailed meat quality for the consumer in our current breeding program and we’re now able to produce high quality beef every time for every meal. We’ve got the science and we’ve got the measurement of the live animal. What I think the big question for us as breeders is how do we meet this next set of challenges? And I think we would say that is firmly in the area of climate change and a more variable climate in our production environment. And so for us that’s about breeding cattle that are more efficient in converting energy into protein. And of us being able to develop a production system where we’re able to cope with the change in climate. In our business that’s meant really doing a lot of new things like building a weaning yard so we can take the cattle off the hills during the dry autumns. Developing some properties which have very good pastures in the summer, particularly lucern so that we can store a lot of fodder for those tough years. And really trying to select animals that are more energy efficient. And so we’re spending a lot of time trying to get what we call the growth path of the cattle right. We want them to hit the ground at the right weight and then grow very quickly and then stop growing so they don’t become too big. And for us that’s really all about producing an animal that meets consumers’ expectations but also meets the demands of a changing environment with climate change. So, the reproductive technologies such as artificial insemination or AI and embryo transfer or ET have major advantages in that they allow us to get greater use of superior genetics but they also have some disadvantages. So, when trying to run our breeding programs we’re trying to balance that the maximising of genetic improvement with also maintaining genetic diversity. And by going out and disseminating and widely using superior genetics it does run the risks that we will reduce the amount of genetic diversity within the animal population or within the beef population. And that can cause several disadvantages. There is a factor called inbreeding depression where we get less performance or depressed performance of animals because of a lack of genetic diversity within the animal. There’s also we can have some genetic defects creep up where animals that have a particular defect within their DNA by populating that and breeding that to an animal which is closely related we can end up with animals which start to express a few defects. So, things like being born dead or having some deformities that we need to manage. Pleasingly though there are some technologies available now which enable us to do both, to maximise our rate of genetic improvement while maintaining our genetic diversity. So, there are some mating allocation technologies such as a program called TGRM or Total Genetics Resource Management. And a newer version of that called Mate Cell which enables beef producers to specify the size that they have available, the dams that they have available, their desired breeding goals, put those into the computer program and it does the mating allocations for them to give them the best possible outcome where they maximise their rate of genetic improvement while maintaining their genetic diversity. With all this data collection, genetic matching and other in-depth scientific work it can be difficult to see the end goal. From the farm to the lab to your plate, it’s all about generating the perfect steak. Well done. Music .

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