Good evening everybody and welcome to another of the webinar vet webinars on Yoni's disease. We have a very special lecturer or speaker tonight, and once I get into his CV you will see just how qualified Peter Orpen is to talk to us tonight. Just a little bit of housekeeping for those, folks who haven't joined us on a webinar before.

My name is Bruce Stevenson and I will be chairing tonight. Any questions that you have, you can simply hover your cursor over the screen. You'll see there's a little Q&A box there.

And, quite simply, all you need to do is just type your question in there. What will happen is that it'll come over to me and we will hold it till the end. And those questions will then be posed to Peter at the end.

So if you've got any questions, feel free to type them in there, and, . They will then be answered at the end. When the webinar is finished tonight, there will also be a questionnaire up on your screen that pops up.

If you wouldn't mind just giving us some feedback on tonight's webinar, that really does help us and we would appreciate it, in planning future webinars. So as I promised you, a great speaker tonight. Peter Orpen graduated from Bristol University back in 1983.

He worked in New Zealand in dairy and beef practise for a year. In '87 and he returned via Southeast Asia and China. He has chaired the British Cattle Vets Association strategic Review in 1996 and worked as part of the BSE and health planning working groups.

He's a past president of the British Cattle Veterinary Association of 1999. He's currently a director and senior manager of a 28 vet practise up in Lincolnshire. He's primarily involved in dairy work with consultancy, lecturing and management.

His major interests are in preventative medicine, medicine, health planning and practise development. His particular interest is Joe's disease and a cost-effective control mechanism. I think Peter has got more publications and references behind his name than I've got letters in my whole name.

And it's really impressive from training over 400 UK vets about Yoni's disease, through training 600 farmers through Yoni's disease, co-developing, the complete online Joni's module. He's director of, My Herd Health.com.

He leads up the UK, Yoni's strategies. He's published papers in international, publications, and the list goes on and on and on. Peter, if I go through everything, I'm sorry I'm selling you short here but I'll be here for longer than you will.

A very impressive CV and welcome to the webinar vet. It's over to you. OK, thank you, Bruce.

Yeah, so, we've got quite an exciting sort of 50 minutes ahead really. What I'd like to do is to, take you through some of the real updates in Yoni's disease, and it's a rapidly moving sort of disease. As Bruce said, you know, I'm very much, a practitioner, and this is the slant I'm gonna take today, is how we can practically use the science and information that's coming out there, to best improve our strategies, on farm.

A lot of my experience has been gained from working with farmers, but also with the use of my healthy herd and the data that's come from that has helped sort of enlighten us in terms of what the risks are that are out there in the national herd and how best we can, handle them. Declaration of interest, I mean, obviously, because I'm the director of My Healthy He, I have a a declaration of interest there, that's a web-based tool really to help plan and control and manage infectious disease. The benefit of having that declaration is obviously we have the information that comes from it, so, I'll share that with you today.

So, the agenda and learning outcomes really, the first sort of 10 or 15 minutes, I'm just gonna update you on the National Ying Management Plan, where that came from, where that's going to. Then I'm going to update you on some of the field research on, on yoni in the UK, and then, and we're gonna discuss a little about the importance of the damned calf effect, calf to calf risks, and breeding policies and how we can integrate those to create effective control programmes. And then we'll.

We'll then just touch on tips to expand your consultancy advice and your own practise, and, and how you can sort of get those programmes to work. So it, it, it gets, fairly intense in the middle. You'll have to concentrate quite hard in the middle, but basically it gets, slightly easier towards the end and, and hopefully that will work for you.

So the National Yoni's Management Plan, what's it all about? Well, it started off really, these are the, the objectives of the management plan, to control and then reduce the incidence of Yoni's disease in dairy cattle with a long-term objective of eliminating the disease if it becomes technically and economically feasible to do so. It's unlikely we'll eradicate it, but it's a disease reduction programme.

This is not some sort of binary yes no eradication scheme. It's a method of reducing the incidence of Yonni's disease in the UK dairy herd. When we set off in 2009, it was really an engagement programme.

We wanted to engage all dairy farmers in effectiveoni's management, and we firmly fixed it on the basis of predicting and preventing the disease. So if we focused our efforts on protecting the uninfected herds, as well as managing the infected herds, we would get ahead of the disease. So that's a real difference from what many international schemes are, which end up being focused on infected herds.

Our key priority also is to remove barriers to engagement and basically motivate both vets and farmers to take positive action. There's a great paper there which was published in Vet Record, the predict and prevent paper, it's been cited in many journals. That's worth a read actually, because that does summarise a lot of that work.

So what we're trying to do is to break the Yoni cycle. So typically Yoni's disease goes cow to calf, through milk faeces and in utero, and if we can break that cycle and stop the calf from becoming infected, we can stop those heifers coming back into the herd. Very, very simple thing to think about, but we've really got to focus our efforts on breaking that cycle, rather than just culling cows.

That's one of the common mistakes in Yoni's disease is that we just cull cows, but we don't break the cycle. So what progress have we made with the National Yage Management plan? We've put that emphasis on engaging farmers.

We've had, we've argued our case to make sure we don't classify herds, because that would disengage in er infected farmers. We've tried to sort of get joined up messaging between vets and farmers so that we all sing from the same song sheet, and we want to engage all herds, not just the er uninfected. We've also sort of encouraged a strategic approach, really, and we've developed 6 Yoni's control strategies, which we'd like you to choose one of them, which is appropriate for any given herd, and we've put risk assessment and management central to control.

Yone's disease is managed by reducing risks. It's not managed just by testing, you know, testing is only a small part of it. And we want those plans to work so that they have to meet the farmers' aspirations, resources, prevalence and risks.

So that's where you come in as a vet, you have to assess that and then decide the right plan for the farm. In the 1st 5 years we spent a lot of time doing education. There was about 300 meetings across the country with about 25,000 farmers.

There was a whole group of vets that trained up and educated those farmers. And, and we, during that period through some of the healthy livestock work and other work we did, over 2200 farmers completed risk assessments using my healthy heard, and we did a lot of veterinary training as well. There's been the Yoni's conference as well held at the Worcester, and that's been well supported.

In 2015, it was sort of cranked up a bit more. We decided to strengthen the engagement progress process, and we developed an action Yoni's website, delivery team we're recruited and paid for by the group to help coordinate messaging and, and support the website, and we developed a technical manual, for, for the vets as well. So, in the early stages, really, all we wanted you to do was to define the strategy.

So put in place a strategy that was appropriate for the herd, you know, the low prevalence, low risk strategies would be biosecurity protection monitor and improved farm management, those sort of approaches, and then if you had a higher prevalence, high risk, you, you had, different strategies that would fit that model. What we found when we vandalised the data, we looked at 839 herds just in the Healthy livestock programme. We found that the most popular strategies were quarterly testing and targeted risk-based control, and then a single single annual test of animals, and, and risk management.

So about sort of 50% of control plants are testing involved, and others were actually involved with, you know, improved farm management, of the whole herd to limit spread. I'd just like to draw your attention that testing and culling is, is quite an aggressive strategy, and it's not one that is very popular with dairy farmers, and neither is Biosecurity protector monitor. So in many of our herds, we have to select strategies that fit the farm, and these don't fit the, the, the, the farming profile, the risk profile of the UK herds.

In 2016, BCVA very kindly sort of, developed a webinar and online assessment tool, and over 720 vets have been trained in, in Yoni's, work and, and this strategic approach, and the aim is that these trained vets will then be used to deliver on the National Yonies Management Plan. So if you're not gone through this programme, then I'd urge you to do it. It costs very little money to do.

You, you spend a couple of hours doing it, but you, you're brought up to date with what you need to do to implement the national management plan, and that allows you to sign the certificates, that are required to accredit the herds. So we're entering phase two, quite an exciting phase now. We want meaningful, credible vet and farmer interaction.

This is not just a tick box exercise. We expect to have, you know, proper on-farm consultancy delivered, where you actually put in place an appropriate and robust plan, and you're then asked to certify that a written control plan is in place. So It's also, I just want to remind you, this is a totally commercial scheme that that is run, it's supported by the milk processors and Dairy UK and AHDB, but broadly, the, the farmer pays for the plan, the farmer pays for your time, the processor encourages, and all we're doing is providing the structure for you to follow.

What's gonna happen is that. You will be asked to actually sign a veterinary declaration that you're confirming an assessment of Yoni's risk and status has been undertaken on this farm in the last 12 months, and you've put in place a written Yoni's management plan, which has been agreed with the herd owner, and the plan complies with the objectives of the National Yoni management plan. So this declaration has been passed by VDS, they're comfortable with it.

So, you know, that's what you're tasked to do. Alongside that, the farmer has to confirm that an assessment of risk and status has been undertaken, and he undertakes to adopt the written Jose management plan. So, just to sort of graphically summarise it, you've got to work out the risk of Joe's disease using a structured risk assessment, .

Established a status using either a 30 car screen, a whole herd screen, or clinical history or called screen. It's entirely up to you what you do, but it has to be a reasonably sensibly robust, surveillance strategy. And then you have to develop a written plan based around, the six national Yoni management plan control strategies.

OK, so I've talked enough, and what I'd like to gain from you is what do, what are you doing with Yer's disease? Over to you, Bruce. Right, thanks Peter.

So guys, quite simply, I'm launching the poll now. All I need you to do is just click on the answer which best represents your situation, and the system will do the rest for us. So go ahead, start voting now and literally just click on the answer that you feel is most appropriate for you.

We'll give you a minute or so to to answer those questions and then we'll feed the results back. Come on guys, don't be shy. This is completely anonymous.

It's nothing, nobody's gonna question you on it. It's, it's really just some useful information for Peter as to the audience that he is speaking to tonight. Right, we've got a couple of stragglers in Pete.

I'm gonna give them another couple of seconds just to to give us some answers. Right. Guys, we need to close this polling now, so let's end that and let's share those results.

And you see them on your screen, Pete? Yeah, I've got that there. So yeah, that's, that's interesting.

I mean, I, I would anticipate we've got a, a, a significant opportunity to develop proper consultancy work with farms. A lot of practises have got oral plans in place, but they may not necessarily have the written plans in place, and I think this is the, the next big step and the next big opportunity for, for vets in practise. OK, so just to summarise, by October 31st, 2018, farmers linked to processes that are signed up to the national earnings Management Plan are requiring the farmers to complete their veterinary declarations.

That's about 80% of the UK national supply are being asked to do this. Only trained BCVA the only facts can sign the declarations, and it's going to involve a structured risk assessment of disease. You've got to evaluate the disease status and prevalence and develop that Yone control programme.

OK, so, that's enough about the plan. Well, in order to deliver the plan, you you you need to have a bit of science behind you, so this is a bit of the update on the, the research. The first bit of research I want to highlight is some work that was undertaken by myself where we looked at 394 farmers and we asked them about how they were getting on with Joni's disease.

Then I'm gonna share with you some of Karen Bond's PhD work, where she looked at 6 UK herds in real detail over a 5 year period, looking at the relative importance of risk there. I'm gonna refresh your knowledge on Cyril Nielsen's or the Danish work, which I think is still very valid, and then we're going to just focus on a bit about the relative importance of risks and how best to manage them. So this is a fairly meaty section.

So this publication here is published in The Last Cattle practise, winning farmer Engagement, and I'm just gonna take one or two key points out of that paper. And we actually wanted to try and assess the level of engagement, what concerns and problems farmers were having, what benefits there would be through control and and what would drive further engagement. I can't talk to all of those, but I'll just pick up some of the key ones.

Of those that had survey that actually responded, we have actually got a large number that have possibly engaged, so we've got over 93% that have actually got some form of control plan in place already, which was, quite heartening to see. When asked though, what concerns they had about the owners' control, and, we were pleasantly surprised. We got nearly half of them saying, well, don't worry, I've got a plan, I'm, I'm happy.

But there were areas that were difficult for them, insufficient building to segregate high and low risk cows at calving, challenges with tests, they were a bit confusing, and, and, and there were some, some difficulties there with some farmers, and there were some, some challenges with regarding culling as well. So you can see that there's a real role for a vet to help the farmer in those areas. If you ask them where the problems lie, you know, different question, but we get a similar sort of situation.

Over half of them are having challenges segregating high risk, or test positive cows calving, which is one of the fundamental, parts of Yoni's control. There's challenges with TB testing interfering with the test results, and this difficulty of knowing when to call positive cows. OK, so let's just think a little about those and we're then gonna move on to some further research.

Let's just think a little about risk management, why we're, why we hammer on about risk management rather than relying just on tests. Well, the Joni's disease is, is very different from many other diseases. It it's predominant sort of stage of infection is one of latency.

It, it's very slow to progress and so control requires really management of risks. And there is this Battle between immunity and the actual infection. And this is complex, and it's not easy for the farmers and, and, and some of the vets to, to, to, to appreciate.

And we almost also understand that surveillance tracks the history of infection, so it's, you know, just relying on testing, you, you're almost like 5 years behind the curve. So another key paper there, 2012, that summarises the risks of Yoni's disease entering and spreading within UK dairy herds, so if you're keen to catch up on that, sure that's still relevant today. So what do we have to do differently?

We've really got to use risk management as a key tool to predict and prevent the disease, surveillance is history, risks are predictive. We've got to appreciate it's an iceberg disease, so clinical cases and test positive cows are only a small proportion of the infected cattle. And we must take a non-binary approach to test results.

Don't think about positive and negative. Think about basically risk, you know, so the higher the the result and the more repeated the result, the higher the risk that animal has of shedding, and that's a probably more constructive way to think about the the disease. Whatever we do, we've got to engage the farmer because the control lies with the farmer.

So, you know, really we've got to motivate the farmer to commit to the controls. So we quite often do that by providing sharing problems with the farmer and ask him to solve them. That often seems to work best.

Bit of an update really on this latency issue. Early work from Whitlock showed that for every 4 to 8 subclinical animals there were 10 to 4 sightly infected animals. And there's some recent work by Shuen where they sampled the herd and they found 2.2% of the animals tested positive, but when you actually, looked a lot deeper into using tissue sampling, the infection rate was much higher.

So, you know, that really makes you appreciate that the true herd prevalence is typically 2.5 times the test prevalence, you know, that's what you're really looking at. So just because you have a situation where you have one animal testing positive, it doesn't necessarily mean.

That the true prevalence is, is as low as that. The disease effects and this risk management, this is what I saw on Nielsen's brilliant slides, and it's important to appreciate the difference between infection and infectiousness. So basically, many animals are infected when they're herd.

They may not necessarily all go on to develop the disease, but as time progresses, they can actually have immune response with control, but then they lose control of it and the bacteria leak into the bloodstream and stimulate an immune response. So, our objectives are to pick up those animals that demonstrate an immune response at an early stage and and segregate them. We then those results, use those resorts to alter breeding decisions, that's typically what we're doing with farmers if we've er using regular testing.

And then we'd also use those results for prioritising animals for culling. So in heavily infected herds, you know, we would be looking quite closely at at test results. Testing though, if we just follow a test and call strategy and just test and cool cows and we don't control the risks, we won't reduce the incidence.

In order to reduce that incidence, we've got to put in place risk management, so that's really, really important. If we do nothing, the disease gets worse, if we manage those risks, we can do that. So how quickly you remove the disease from your farm will really depend on how good you are at helping farmers to manage those risks.

And we sort of struck upon this sort of graphic, really, this is the four pillars graphic, which was developed and supported the My Healthy Ed programme, and we identified that if we want to have robust disease status, we must manage the risk of entry. We must do what we can to sort of strengthen resilience and immunity. We must have appropriate surveillance and we must have appropriate control.

Now the challenge with Yonni's disease, if you're not careful, you can end up with this, where you just test but you don't do the other components and you don't have a very robust disease status, and that's what we must avoid. So, let's talk a little about, Yoni's risks. There are two components.

There is risk of disease entering the herd, which is predominantly purchase to carrier cattle and slurry, and then the risk of spread, and we're going to focus a bit more on that risk of spread within the herd because that is so important to appreciate. So how do these calves get infected? The key transmission routes really are here.

And There is a dam to calf effect. We know there's milk and lostrum, but by far the most important results are going to be faeces contaminating calves, others environments, and this is the most significant route. And quite often what we find is robust control of these roots, but this area quite often isn't controlled as well as it should be.

And we must also appreciate that this risk, the dam to calf effect, is a 1 to 1 risk, so one cow can give birth to one calf, whereas these risks, you know, if there's a shedding cow and it goes into a communal calving yard, it has the potential to contaminate the environment and infect many calves. So it's important to appreciate the difference between the two. So when we're setting up our management programmes, we control the major risks as a priority.

We make sure we shut off the one to many risks. We make sure also we don't forget the risk of disease introduction because that's crucial. And we must also appreciate that as disease control, as we get better and as we reduce the incidence, we can actually tighten that screw even further, and we can strengthen that plan year on year.

So it's so important in the first year and the first setup of the herd that we don't overwhelm the farmer with detail, so we're seeking to engage, get those one to many risks in place, and then as we've got those embedded, we then starting to tighten the screw. Make sure you set realistic expectations, very important. NMR, they basically did some work looking at 459 UK herds.

They used the My Healthy tool to undertake some contemporary risk assessments in 2017 to see how well we're getting on with it. And they've worked with certain practises to facilitate Yoni's control as well, and they have a system for using this system to support their herd-wise farms. Busy slide, but I'll just explain how it works, but basically what they found was that the ability to control risks in the biosecurity risks were not good, so 40% of the herds are still at high risk of disease entering the herd.

We still had 40% cow to calf, were high risk of having cow to calf transfer, and we had poor control in the adult area. We're not too bad in terms of milk and clostrum and young stock risks. But it wasn't perfect in those other areas.

So we looked at that data in more detail, and we found that full segregation of high risk cows from maternity pens only achieved in 39% of herds, which is slightly disappointing. So there is some creeping of high risk cows into those maternity pens, which can be a challenge. There's only 40% had a very robust system of making sure they didn't come in.

And we also found that culling was a tendency to hang on to cows and not remove cowser within a defined period. So, you know, there was a a a significant proportion of cows that weren't removed promptly. So just to summarise.

Many herds are testing, but not all are controlling. I think it's really important and if we are going to get on top of this disease, we have actually got to get to the fact that more herds are controlling the disease, we've got to manage those risks. OK, let's look at Sor Nielsen's work.

He, he's been a key scientist in this area. He was the architect of the quarterly milk testing scheme that was very successful in Denmark and has been very usefully employed over here as well. And he's done a lot of work.

And what he found, and this is a published study, where he quizzed over 1000 farmers about how they were controlling the disease, and what, what control systems they were using and. The test test positive rate was about sort of 7 or 8% here, and what he found was that herds that were buying in cattle, they allowed those red cows to calve again, and milk from green cows, they had milk from green cows, those ones really didn't control the disease. The ones with the best control basically stopped purchasing animals, or less than 15% of animals, and they've fed waste milk from green cows, but they had good control of culling, then no, or some red cows carved again, so culling has become very, quite important really, in terms of managing this disease.

And he summarised it, sort of saying, well, to conclude, culling of repeated antibody positive cows can be associated with a decrease in the prevalence of maps specific antibodies over a period of 4 years. And the culling effect may be attributed to the highest frequency used to present in in the present control programme. So the aim is to try and ship these infectious animals out, identify them quickly, and remove them, and reduce the overall level of map in the environment.

So it's an important thing. Has it worked? Yes, we've seen that reduction here.

It's gone down from 6 to 8%, down here to about sort of 2%. So the programme has worked despite its limitations and despite the fact that it's not been universally applied. But within that, you'll have some herds that have actually done it so much better because they have applied the system more, more successfully.

So those 2006 strategies that were set up about red cows being called prior to next calving, segregation of yellow and red cows, making sure green cows were only used for the source of colostrum, those really do sticker today. Busy slide, I appreciate, and I, I just want to sort of draw your attention to it. This is one of his papers in 2009, and this is test prevalence, and if we look at high shedders here.

And this is when they start to actually test positive here, at this point. You will get animals testing positive 2 to 3 years before they actually start to sort of degenerate and become heavy shedders. So that explains this sort of oscillating effect.

So it is perfectly normal to have a proportion of cows that will do that. But the good news is the majority of these test positive prior to heavy or persistent shedding. And we must appreciate that we'll get antibody concentration 2 to 3 years before, before they start shedding.

And we must also understand that if you just do one test, there's a risk that you may not pick all of them up. So, you know, the logic is to do repeated tests and then to categorise animals into these infectious groups. We he also did some work looking at clostrum and milk as risk factors, and basically the risk factors for transfer of map through milk are nowhere near as high, so if they're fed clotrim from multiple cows, you've got a slightly higher odds of ratio of being EISer positive.

If the so-called foster cows, you know, obviously that's going to be a a a a a significantly higher rate because they're gonna be exposed to faeces as well. But what they did find, feeding bulk tank milk and pulled milk from cows with high somatic cell counts didn't increase the risk, so there must have been some dilution effect there. So pooling of milk and pool and loss appear to be risk factors, but their effects have probably been overstated.

And it seems that we're not going to ignore those risks, but don't just let your farmers buy pasteurizers and focus on the milk risks without actually controlling the other areas as well. So, you know, he did put that caveat, he strongly recommends that clostrum is fed only from down to her own calf or from one calf to one calf, and that pooling Cross to be avoided. So he is sort of still sticking with that, but just focusing on milk risks is probably not going to be enough.

Just be aware, when farmers are collecting milk, you can see why it's a hazardous pastime. So if they are collecting milk in parlours, make sure you put lids on buckets and find fairly secure ways of avoiding faecal contamination, cos that can, that can be a common way that infection can be spread. So just to summarise what they found for Danish work, biosecurity is really important to prevent map coming in.

Culling red cows at the end of lactation has a profound impact on reducing overall prevalence and waste milk feeding was less consistently important. OK. So Next area really which I think is an important thing for those of you that are trying to manage yon in larger herds, is the concept of the super redder.

Not all cows shed map at the same rate, and of those heavy shedders, some of them become super shedders, and they can produce up to 10 billion organisms per day. So massively infectious, and the rate of shedding can be up to 2000 or up to nearly 20,000 greater than the low shedders. So it absolutely can overwhelm the farm with map.

Whitlock did some work on this, and he basically found that the only need about 100 organisms to infect calves, and less than 1 gramme from the ultra super redder is likely to infect neonatal calves. And so if we have these animals retained in the herd, we're really gonna struggle controlling it because people are gonna tramp it around the farm everywhere. And what they found was that You know, this is when they were sampling this farm, and this is how many pens were infected and how much infection was there.

Once they sold the super redder, the herd basically, those areas became negative. So, you know, it's so important to remove these super shadows. And to put it graphically, if this is a 1 litre of faeces here, and that was spread across a communal calving yard, and this is a tank with 10,000 litres, well, you can imagine if it's a super shedder in a communal calving yard, you're really gonna struggle with any degree of snatch carving or anything to stop infection from from entering the calf.

So just to summarise, super shadows asymptomatic, they don't have diarrhoea, there's no evidence of weight loss, the, the 2 to 3% are culture positive, and 1 gramme can be enough to actually cause passive shedding in adult cows and, and can also infect calves. And it's relevant in these larger high prevalence herds. So it will start to overwhelm the farm, you'll get fomite risks, you'll have pasture and slurry and aerosol roots becoming so much more important.

And that probably explains this wide variability in the importance of risk factors in in different studies. OK, so that's the super shedder effect. The other effect is this dam effect and er this is the risk of cars becoming infected, born from infected dams.

This is well known, and the study here looked at it, and they found that cows with serum positive dams were nearly 7 times more likely to be serum positives. So if you're actually a a calf born from, from an a serum positive dam, you know, there is a greater risk there. And they've found in this study that 84% of the effect was dam effect and 15% through other exposures, and you know, in, in, and that, and that was a significant finding.

Well, is that relevant? Is that something that happens in the UK? Karen Board did this elegant piece of work where, She managed to follow 600 female calves from 6 herds, and she videoed them, she observed every possible birth, and she was able to look at all the possible possible routes, how much time we spent in the calving pen, the cleanliness of the yard, a huge part of work.

And they basically enrolled these 430 300 cows here, and they found that 55 of them tested positive. And they, what Karen then did was to say, well, of these positive cows. What reason was it?

Was it anything to do with the dam, or was it down to milk, or was it how long they spent in the carving pen? And they looked at dam status, and they looked at negative dams, inconclusive ones, and ones that were positive at various stages, and they looked at the transmission results. And what was really surprising was that the calves born from infected dams were 2.5 times more likely to be infected, but most surprisingly, positive at calving, I could understand that, but positive within 12 months.

Yeah, I could kind of get that. But there was also calves being infected more than 1 year after that animal went positive for the first time. So that suggests that there is a potential risk of transmission from these in positive animals in the period prior to them becoming positive.

So we have to think carefully about how we're gonna manage that risk. So when we're looking at the effect, the positive dam effect there was there, and it was, it was significant when we looked at all cows, long time in the dirty pen was there, there was other factors. But if a calf is born to a positive dam, the dam effect is the, the predominant sort of risk factor.

If it's born to a negative dam, you're looking length of time in the dirty pen, and, and these other environmental factors. What she found that the serum prevalence of herd-wise herds, about 70%, it takes her about nearly 5 years to go red, but what often happens in herds is the red cows hang around for a long time within the herds, 30% for more than 12 months. So this means that calves born from any dam testing positive at a greater risk infected dams probably shed at time of stress of calving, sufficiently to infect their calves, but not sufficiently to trigger a persistent antibody teeter.

So that would possibly explain it, that's our hypothesis. So we must view any cow testing positive in its life as a higher risk of transmission to his calves. So what do we do?

Do we do nothing and accept the risk of the 1 to 1 transfer until the major risks are controlled, I mean that's, that's an option. We can possibly source replacements for low risk cows, repeat test negative ones, or breed heifers from mode heifers. Or we get more clever in terms of not serving or breeding replacements and test positive animals.

And if you've got sufficient replacements, you could go down the path of saying, well, we're gonna go back and look out those calves and make sure they don't come back into the breeding herd. And that's gonna depend on the prevalence within the herd as to which of these options you pick up. But whatever you do, make sure your carving pens are kept clean and you remove the calves early in any event, cos I think that's important.

So just to summarise it then, summarising Yi's risks, make sure when you do your planning, revi review your biosecurity and biocontainment risks. Control the one to many risks, control to 111 to 1 risks according to the aspiration of the farmer, replacement numbers and, and the prevalence. Put more emphasis on culling out their high risk repeat test positive animals to reduce the map burden and think about those 1 to 1 risks if you can.

But make sure the controls are economic and practical. OK, so that's the sciencey bit over, it's gonna get easier now, we're gonna talk about some top tips for control. That's the next step.

So you've got to develop a Yoni's plan with your farmers. So make sure you select the right strategy. You've got to review the prevalence, you've got to look at the risk of entry and spread, look at the resources, look at the aspiration, and then choose a strategy to fit.

So fit it according to this matrix and then you'll actually be successful. You've got to make sure it's a a a sensible plan for the farm. Don't be frightened to change it.

If it's not working, change it. If you can't apply it, change it. Don't stick with a broken plan.

Think about results to aid culling and segregation, you know, you would be identifying animals in this herd 268, you'd say this is a repeatedly testing positive, that one should be culled, which don't you serve? You might say, well, 178, this is one I'm choosing not to serve, at all, and. You may be saying, well, this one I'm going to breed to beef, these ones are low risk animals.

I think they've got a longer future in the herd, but I think we're going to make a decision. Do make the decision based on those three categories, what you call, which you don't serve at all, and which ones you actually breed to beef. Once an animal's pregnant, farmers are reluctant to cull it, so the, you know, focus a little on this area.

Make sure you have find ways of making sure that everybody knows which farmers are which are testing positive and which are not. And think about how you can create that green carving line, how can you create a low risk environment for the replacement calves to be worn? Make sure no test positives enter the pen.

Make sure calves are removed promptly in any event, and it's a clean, well-drained pen without any inoculation points. So these are examples of it, individual rubber floored carving boxes, these have become more fashionable, certainly in the west of the country. In my area, we've got plenty of straw, so we can get well bedded maternity and dry cow areas with clean udders there.

I think that's important. What other practical examples have I got? Well, just think about, these commodore calving areas.

These are high risk. They're very high risk of transfer of infection, and you can get dirty udders and legs. So if you see this as your communal area, then you have to do a little more to sort of try and improve that.

Similarly, this sort of environment, you know, this is gonna be a great way of spreading disease from cow to calf, so it has to be managed. So in this particular herd, this is a practical example here, this herd, it had this, they had a mixture of high risk and low risk animals here. The all came out through this inoculation point.

You'd see them in the field, they look absolutely clean and fine, you'd think, well this is not too bad, but when you look at the legs and where the legs were touching the others on a wet day, there was a lot of transfer of map from the legs to the teeth. So what we were able to do, this her he had an implement shed next to this shed, and we were able to create 3 calving pen areas where 5 animals at a time we'd go in there, prior to, we, we separated the high risk cows that drying off, and then basically when they came from the dry period, they went into these clean transition areas. And it's been quite heartening to see the reduction of disease in this herd er as a result of actually improving this environment.

The other way of looking at it is to look at the cuddle box idea, so if you can't segregate the cow as well as you could think of more creative ways of segregating the calf. So basically the calf is very quickly removed and put in a cuddle box awaiting removal to the calving accommodation. So, you know, you're using that system, the mother can lick the calf but it basically can't, you know, contaminate it with faeces.

Homemade devices can be made here, you know, not so pretty to look at but equally as effective. The cal signals Group show one where you've actually got one on wheels, and so you can use it as a calf transporter. So, remember, 80% infections occur in that first month of life, a lot of it is going down this faecal route, so it's really important to sort of break that cycle.

And we've really got to sort of try and stop that car from becoming infected. That's what we've got to focus on, put all our efforts in there and the risk management. And if we're gonna get clever at it.

We've got to not tolerate these red cows remaining in the herd forever and a day. We want these cows to be the repeat high test positives, and this is Soron Nielsen's recommendations. 2 counts greater than 60 on the milk Eliza, you know, they basically need to be removed.

They're classified as high risk cows and they're removed within 3 months and certainly not allowed to calve again. We create this green carving line using risk management and effective segregation. We make a real effort to protect those young stock from exposure to map in those 1st 2 years of life, and then we can push healthy animals into the system.

We can segregate those and snatch calves and test positives, you can decide whether you choose to retain those animals as breeding propositions or not, that will depend on farmer aspiration and and numbers. You can manage also possibly infected cars by tagging and rearing with beef and culling. And we want to make sure that disease free replacements are reared in low risk map environments.

And we can use a lot more selective breeding to limit transmission. You know, the use of sexed semen and heifers has been very helpful with Yoni's control, for instance. You know, that really has actually been a a real game changer, I think, in terms of managing the disease.

So critical control points just in the last 5 minutes or so, call those heavy shedding cows out to reduce the overall map burden, because they're gonna overwhelm the biocontainment measures if you're not careful. Don't let the farmers retain them forever and a day, and to achieve that, you want to prevent them from being served. Control and manage the lighter intermittent shedders to block transmission to cow to calf at critical stages.

And limit the spread of infection to calf to calf from heavily infected cows by selective breeding, culling and calf segregation. So we know there is some calf to calf, risk, so it's important that we don't get calves that have been snatched from red cows and from high risk animals and put them in to our green calf line. You know, that's not a good idea, so you want to rear them with the beef cows.

So what are we gonna do in a practise? How could you do this differently on a practise based system? I think you can create awareness of your owners by talking and communicating to your farmers if you've not already done so.

Spell out the opportunities and the positives, don't talk about the negatives. Permission in the planning opportunity, your next routine visit, say to the farmer, is it OK if we sort out your your national ears management plan, we're gonna have to do it. Let's do that at the next visit and permission that opportunity.

Don't try and do it on the hoof. Create the time to do a good job and do it well. You know, don't do it when you've got to hand up a cow's backside.

That's not a great way to deliver consultancy. You can use tools, there's a bit of a plug for my healthy heard, but you can do this on a wall chart, you don't have to use the programme, but in essence, how the My Health He practicers are doing it, they're able to actually enter risk assessments and they can, traffic lights score the risk assessments there, they can see the surveillance status and what the disease status is, and they can monitor all the herds that way, and, and, and do it in a structured fashion. But I'd urge you to have a system of actually tracking your progress.

Keep up to date, we've revised the actions, website, you some documents on there, there's real progress and protocols on there, so do revisit that site and you'll be able to download a lot more of the certificates and access more information on the strategies and approaches. I think that's very, very important. And You know, what are we trying to do?

What have we got to do, whether this nationally, whether that's within our practises, or whether it's on the farm. The central thing to do is to make sure that all the vets and farmers understand how Yoni's disease is spread and the critical control points. You've got to complete the BCVA accreditation, if you haven't done so.

I would urge all the vets in the practise to get accredited. You may choose to make one of the vets a Yoni's champion and and make one or two people go round and do it and deliver a high level of service and make sure that they do it to a very high standard, but you aren't gonna just be able to do this without being accredited. Make sure you do a credible risk assessment of disease of entry spread on your herd.

You can use tools like My Healthy Hed, you can use other risk assessment tools that are published widely, so, you know, it's entirely up to you as to how you do it, but you must do it in a proper structured fashion, you know, to protect yourselves as well. Sort out an appropriate surveillance plan for the herd. Think about clinical cases, agree with the farmer what you're going to do to actually assess the disease prevalence.

And then select the right control plan for your herd. So that's what you must do, you must actually sort of say, well, I've done all this, and then gonna actually work through and agree a plan that works. Don't be frightened of selecting a strategy if you've got a very low prevalence herd, it's a very tidy herd, you might have a, you know, your surveillance shows it's got, you know, limited or low low prevalence.

It might be wholly appropriate to use improved farm management alone without any testing, and just some sort of light touch monitoring on an annual basis, you know, a 30 cow screen just to check progress. So don't be frightened about using just to improve our management, but you know, try not to be sort of sucked into aggressive testing call programmes, for instance, when, you know, the prevalence is too high, you know, you know, that won't work either. So it's been a bit of a whistle stop, I'm up to my nearly 50 minutes now, so I'm, I think, what I will do, I'll hand that over to you, Bruce, and it's question time.

Well folks, I promised you an amazing speaker and somebody who really knows his stuff. And Peter, you more than delivered on my promise. So thank you for doing that.

Right, folks, Peter, we don't seem to have any questions coming through. I think personally for me, I felt your presentation was clear and concise and you, you certainly have given us clear guidelines. I think the, the one take home message for me here is perseverance.

Talk to your farmers and persevere with it. Folks, we seem to have lost Peter's audio at the moment. Oh, you're back again.

Yeah, I've got that, Bruce. Yes, no, I couldn't concur more, so, you know, it's, there's a fantastic opportunity, I think, for practising vets to develop consultancy, to put in place written control programmes, and to actually sort of increase fee income for the practise. So, you know, you can help your farmers, but you can also help the practise.

So I'd urge you to get involved. Yeah, that's excellent. Peter, once again, thank you for your time and your expertise and thank you for joining us on the webinar vet.

To the rest of our attendees, I hope you enjoyed tonight and look forward to seeing you on another webinar soon. To my controller Lewis in the background. Thanks for making everything run seamlessly and we'll see you on the next webinar.

Good night everybody.