Good evening everyone, and thank you for joining us for tonight's BCVA webinar. My name is Sarah Peterson from the BCPA board, and I'll be chairing the webinar tonight. Our speaker tonight is Rachel Hayton, and Rachel has said that she's happy to remain online for questions, so please type any that you may have in the Q&A box during the webinar, and then I'll save them from the end of the presentation.

If you have any technical difficulties, then please also let us know by using the Q&A box and we will do our very best to assist you. If you can't see the Q&A box, if you move your mouse, then the taskbar should become visible at the bottom of the screen. So it's my pleasure to introduce Rachel Hayden as tonight's speaker.

Rachel qualified from Edinburgh in 1993, and after a brief spell in mixed practise has been in farm animal practise ever since. She is a senior clinician and shareholder at Synergy Farm Health, which is a large independent farm only practise in the Southwest and a member of Excel Vets. Much of Rachel's time is spent on mastitis work, particularly focusing on prevention, on farm culture and staff training, as well as teaching the the RVC core farm animal rotation.

She also oversees Synergy's research programme. As alongside this, she's also on the BCBA board, having been elected on in 2017. So tonight, Rachel is going to talk to us about on-farm culture.

Is it a good idea and how do we make it work? So now to hand over to Rachel. Good evening everybody.

Welcome. Thank you very much for, for tuning in. We seem to have a bit of a, a tsunami of webinars at the moment, and, a lot of them are incredibly high quality.

So thank you for tuning into this one. Plan for this evening is, we're gonna talk about the rationale behind. On farm culture.

When, just, look at some of the research that's been done, including how some of the different tests are formed, the practicalities of how, I go about making it work, how I think it works, and some of the pitfalls, and then, and then look at what we should be monitoring and how to tell whether it's, a good idea or not. But before we do that, rather than just talking into the ether, I'd quite like to have, a bit of an idea about who's listening in. So I've got a couple of poll questions, for you to participate and just let, let me know who's, who's listening into the webinar.

So, shall I read out the first one, Sara? Yes, go ahead. I've just.

So the first one is just, I'd just like to know what everyone's area of work is, whether you're a practising veterinary surgeon, in academia, in industry, a student or something else. So if everybody just selects the answer that they can see on the screen there. We've nearly got 100% that voted, so the last few of you that haven't, I'll just give you a couple more seconds.

It's not a catch question. OK, so I'm gonna end the polling there. So tonight we've got 48% of private vets, 9% in academia, 4% in industry.

We've got a good cohort of students tonight, so 29% of our listeners are students and 11% are other. -huh. Interesting.

So you've got a nice mix. So the next question for you, is gonna be just a little bit about what your experience of on-farm culture is already. Whether you already carry it out and supervise it on your plants farms, whether some of your clients are using it, but you're not getting involved at all, whether you're just interested in thinking about it, not at all, thinking about it or actively think it's a bad idea.

So I'd just be curious to know what everyone's starting point is. Again, we're getting a good response, nearly there. So I'll just give you a couple more.

A couple more seconds to decide what your answer is. OK. Oh, a couple more coming in.

Right, we'll end the voting there. OK. So we have 13% of listeners already carrying out supervising on farm culture on some of their clients' farms.

Nobody has any clients using it without their involvement. 72% are interested or thinking about it, 13% haven't considered it, and 2% think it's a bad idea. Oh, brilliant.

OK, that's, that's fascinating. I'm looking forward to the questions from the, from the people who think it's a bad idea, then that's great. OK.

So, I go, I guess the place to start is, is why, why should we, carry it out. If anyone was listening in, to Andy Biggs' webinar last week, I think he did an excellent, exposition on this. So I'll try not to repeat, what he said in case anyone was listening, into that one as well.

But I'm just gonna start, I suppose, with, with antibiotic use. We, we do know that we're under pressure to reduce antibiotic use. The industry responded really well, I think, to the O'Neill report.

So we got our rumour target taskforce. We, we seem to be meeting our targets antibiotic use, but this is, this is not going to go away. This is a constant downward pressure.

One of the other things that came up in the O'Neill report was the need for rapid diagnostics. And again, in the government response, they picked up on that and, and, you know, referred to the fact that it's not a good idea to just prescribe antibiotics, blind. And if, if you had diagnostics that could help us to, target them, then that would be, a good thing.

So, how do we reduce antibiotic use, in mastitis? This is actually, a slide that I lifted from, another talk, which was actually about quarter pro, but the points it makes are absolutely spot on. So the best way to reduce antibodies in mastitis is actually to reduce some mastitis cases.

And that, that remains the same whether you're carrying out anharmaculture or not. So if, if you, if you're not already trained up, get familiar with the masta control plan, get familiar with Quarterro. That's the best way.

But there are other things that we can do as well that are that are pretty important. I think it's, it's useful to look at our approaches to treatment. I think these days we, we feel that systemic antibiotics are not necessary for mild cases, and that can make quite a big difference.

And also, I think there's been a lot of scrutiny of, of the, course lengths that farmers are using, and some of them are, are, are giving an awful lot of tubes per case. So that's something that's worth looking at for your clients, or how many tubes are they giving per case. And if anyone hasn't done milkshare training, likewise, that, that, is, is really useful for looking at that topic.

And then thirdly, we can minimise use by selectively treating cases, and that would could be done blind or better, would be done with evidence, such as on farm culture. So if we get a case of clinical mastitis, we sort of have, have two options. Most cases get treated blind with a broad spectrum antibiotic.

But we do have the option to not treat. If we don't treat, we can just monitor and watch the cow. We can segregate her and put her in a separate group.

We could draw off, or we, we could call her. But even if we treat her, we also have the option of what we treat her with and whether or not we try to treat her a little bit smarter and consider narrow spectrum. But in order to make those decisions, we really need information.

So a lot of farmers already would be. You know, taking into account the, the cow history, you know, a cow who's had a lot of cases of mastitis is unlikely to cure. She's gonna have a much lower chance of cure.

She's probably less likely to get, treated. Likewise, cows with chronic high cell count have a lower chance of cure. So that's information maybe the farm already has.

And then if we could add into that some knowledge of the bacteriology or even, antibiotic sensitivity, that would, that would add. To our decision making. Because we know that some cases are going to get better without treatment.

We also know that some cases will not get better, regardless of treatment. So really, in an ideal world, we want to reserve the antibiotics for the cases that are going to benefit. Which brings us on to cure rates by pathogens.

Obviously, there's a lot of other factors that are affecting cure rates in cows, but if we look at cure rates by pathogen, this is a review. Carried out by a group that we're looking at on-farm culture. Generally speaking, the grand positives.

We need treatment to get decent cure rates, and the gramme negatives are not so influenced by treatment. So, the E. Colis are, are gonna have a good cure rate, even if, even if they're not, treated.

Clubsciellas are gonna have a lousy cure rate, whether you treat them or not. And, samples that, that, are no growths actually tend to do very well without treatment. So that that's the kind of review of, of various studies.

There are other studies out there with with different numbers attached to them, but the principle remains the same. So the rationale behind on Farm culture is if we can differentiate between gramme negative, gramme positive, and no growth, the gramme negatives are not gonna benefit from treatment. The no growth won't benefit from treatment, but the gramme positives do benefit.

But if we know it's a gramme positive, we also have, some, some, . Scope to perhaps provide narrow treatment, narrow spectrum treatment or even extended therapy. So if we're gonna use antibiotic, use it where we know it's going to benefit the cow.

The, the big question perhaps is that we've got a 24 hour delay, up to a 24 hour delay before treatment. But there's also the option, some, some, systems to treat and then stop if you get a a gramme negative or no growth. So, a little bit of an, of a, of a whistle stop tour of some of the research, .

A lot of the earliest research into on-farm culture has been carried out in the US. In fact, that's where most of the research has been done. To, to be able to interpret that research, it's important to realise most of the systems there are some cuticles, and coliform infections predominate.

So the majority of milk samples will give a gramme negative or no growth in those systems. Having said that, there's, there's quite a few papers now showing really significant antibiotic use, probably averaging about 50% reduction of antibiotic use, with earlier return of milk to the tank and no significant differences in cure. How you define cure is another, is a.

Bit of a minefield, but it could be the days to clinical cure, bacteriological cure, recurrence, treatment failure, and, and, whether or not the cow returns to low cell count. There was also no significant differences in yield or risk of culling as well. So, Research from the US fairly conclusively showing that on-farm culture can be beneficial.

There's been some, a little bit of work from Canada, and that was sort of being done on smaller farms, less conclusive. One of the things that they showed was that, on the farms that didn't get very much mastitis at all, so that would be less than one case per month. The accuracy of carrying out these tests was so poor that they didn't get good results.

What's interested me in the last couple of years is there's been some research coming out of, out of New Zealand into this. Now New Zealand generally has a lot of strap Uist. Predominant gramme positive infections.

So on the face of it, you'd think that pharmaculture wouldn't suit them as well. And yet, there's a couple of papers that have managed to show about a 25% reduction in antibiotic use, for no significant differences in cure rate or cell count. So that's, that's quite interesting because I'll come to this later, but Probably trials carried out on farms that I would have advised not to use on farm culture.

So that's quite interesting. But again, they find that there was variation in the compliance and the accuracy between farms. So how these tests are carried out is important.

So on to the UK, we don't, we're not quite there yet with, with, research, into how, how these tests are performing. There was an innovative farmers' trial carried out by Peter Platter of the RVC, and he found, he, he tested it on UK organic farms. And found no significant differences between cure rates, days to clinical cure, recurrence, and certainly much shorter withdrawal periods in, on average, in the, cows that were where on-farm culture was used.

Obviously, being organic, that was quite a marked difference. It was 11 days shorter. But the numbers were too low, really, to, To draw, to publish, basically.

But there is further work going on UK work to look at, look at on-farm culture in the UK. Pete Down at the University of Nottingham, carried out a modelling study, to look at the cost effectiveness of on-farm culture. Now, He started off by looking at a scenario where the delay in decision making, so that 24 hour delay while you get a diagnosis, he assumed that that would cause a drop in cure rate of 11%.

Now he didn't just pluck that figure out of the air, it was, it was drawn from one of the early US papers. That found the same thing, although it was not significant. So he, he, he used that with a, a drop in cure rate of 11%, he found that basically on-farm culture was not cost effective.

So whatever level your gramme positive cases were, it was gonna cost you if you implemented it. If he took a drop in cure rate of that was much lower, so between 0 and 5%, that changed quite dramatically. And actually, as long as there were less than half of the cases coming up gramme positive, there was cost benefit to carrying out on-farm culture.

And what he found with his model was that the most. Important factors in determining the economic assessment were whether or not there was a reduction in cure rate and also the proportion of gramme positive cases. So if we can be confident that we're not damaging cure rates, on-farm culture might be a good idea.

If we're damaging cure rates significantly, it probably isn't. And things like the change in milk discarded and the change in medicine use actually were relatively unimportant in the cost benefit. Of course, people value different things.

So if, if, if, reducing antibiotics is, is, regarded as a good thing in its own right, then they might have different motivations. So he concluded that Unsurprisingly, there's more scope to cost save by reducing the rate of mastitis, but it could be an additional measure for selected farms. And if we sort of think about the, the components that go into the Cota case of mastitis.

If you're carrying out on farm culture, you might throw less milk away and you might spend less on medicine. So you, those might be savings. The biggest cost, which is the reduced yield, would be unaffected.

The labour will probably actually go up. And the risk of culling death will, hopefully, that wouldn't change, but if it does change, that would, that would go up as well. So it is definitely more cost effective to prevent mastitis.

This isn't just about money. And that's just a, a, a sort of, graph from another study, showing the range of antimicrobial use on farms from, I think it was for, vet practises, in the Southwest, one of which was ours. And it shows a range in an antibiotic use.

So. If you're looking at the farmers on the farms on the right of that graph, they've got high antibiotic use, they've probably got high mastitis. They're probably not on-farm culture is probably not for them.

There, there, there should be other measures to bring that antimicrobial use down. The guys on the left who've got relatively low levels of use already, probably much more suited. So how do we assess farm suitability?

I think the first thing to do is to get some bacteriology from the farm. There's 3 reasons for that. One is, if the farmer cannot take a clean milk sample, this is not going to work.

So first thing, if we get some bacteriology from the farm, we can find out whether they can take a clean milk sample. And if they can't, or if it's out beforehand, then there needs to be some training. Secondly, we want to know that there's gonna be a significant number of gramme negative infections, because likewise, if everything's gramme positive, they're not gonna make any gains.

And we really would like to know that they've got very low or absent staph aureus. So we can look at the, the, whether there's any clues to the presence of contagious mastitis. And if there is, it's probably, Not the right choice.

We also need to know that they're detecting mastitis well. So if we're worried about damaging cure rates by by that delay in treating, if they're already slow in picking up mastitis, that's, that's . To help.

So we really would like farms where we know that they're picking mastitis cases up early. We need motivated staff. We need staff who can follow protocols.

And we, we would like it to be farms that have already got the mastitis under control. So this is an additional measure, to reduce antibiotic use. Generally, I often think it makes more sense on organic farms because they can save a lot more milk, by, by not, not treating.

And actually a lot of robotic farms as well, because some of the robotic farms have got auto automated mastitis detection that's picking cases up. Very early, and some of them, they're picking the cases up before they would have been picked up by milkers. And then it, it does give a bit of a dilemma to the stockman, do I, do I treat this case or not?

And on farm culture can just fill that gap perfectly. So perhaps if you're picking it up when it's almost subclinical, you can have that decision by the time she's gone clinical. The other The type of farm where where this can be quite helpful is the the the farms I call the other cream enthusiasts.

So there's quite a significant number of farmers who already are doing selective treatment. They, they sort of look at the milk, they think it look mild, they test the wind, they decide they're gonna do it adament and and milking out. .

And if already doing that, it makes sense to sort of add in, some evidence to what they're doing. Let's make sure they're targeting, treatment to the right cases and withholding treatment from the right cases. Often I think these guys, they, they, they end up withholding treatment from, you know, mild staph aureus cases, mild pubrises, and then they can, store up troubles themselves.

So the practicalities, . So we need to, we need to pick a kit. I'll talk about the kits that are available, in a little while.

We need to get the farm set up, agree some sort of fee structure and review frequency. This is quite important that it's done with vet support, and we need to get some protocols specific to that farm, drawn up and stuck on the wall. And we need to have some vet backup and lab backup for checking, checking results.

So the kit, I mean the main investment really is the incubator, and sort of egg incubators ordered online. Fairly easy to get hold of for 30 or 40 quid. That those are the ones we're currently using, but we've been through a few.

So we need a test kit, we need some swabs or loops. We've been using the loots that, that, our lab use. I think for on-farm culture swabs are better because you actually want to put quite a lot of milk on that plate.

You're trying to, you know, you're not in, you're not bothered about individual colonies. You're, you're bothered about trying to find what's there. Sterile sample pots, we're using the sort of white screw top ones.

If you can get hold of flip top ones, they're probably better, easier for farmers. Latx gloves, recording sheets or some sort of system of recording, marker pen for marking the parts. Laminated protocols, I'll come on to that.

A clean work area where nothing else is is going on and a do for for disposing of old plates. So for setting up, . The training farmers is pretty, pretty straightforward, actually.

Mostly, if, if it's not straightforward, they probably shouldn't be doing it. Just remind them that if they, if they don't get, if they don't get any growth in the 1st 24 hours, worth just keeping it for another 24 hours. Culture all no growths for up to 48 hours, agree what the treatment protocols are, make sure they're on board with those and agree what the recording system is going to be.

So. A lot of farmers, I think, see on-farm culture as a way of reducing their recorded mastitis cases. They think if it's not treated, that means they don't need to record it.

So I do encourage them to record all the all the culture cases as well. Otherwise it's really hard to monitor how things are going. Just make sure they understand what, Don't mistake milk clumps for colonies, and they need to understand how to recognise a contaminated plate if they've got that sort of system.

So they should be freezing in all the milk samples they take and then they're there if we need to check up on them later. And agree who, who they should turn to if they need advice, and, and a date to go back and have a look, see how they're getting on. Health and safety is actually quite important for this.

So, The A lot of farmers will, the first place they want to set up the incubators is in the kitchen, sort of just above the fridge, next to the kettle, just where they're making their sandwiches. Absolutely not. It has to be in a clean area that's used for nothing else and no food, preparation going on.

So they need to understand that they're growing pathogens that could make them very ill. I think a lot of farmers tend to assume that they're kind of pretty immune to everything. But we don't really want to, to test that.

And we'll talk about the systems later, but some of the systems are actually closed systems that they don't have to open up again are probably better if there's health and safety, worries. So they need to have a really clear protocol, so they need to understand they're only sampling cows with mild mastitis, that'd be a grade 1 or a grade 2. Anything that's sick needs to be treated.

They're gonna plate plate up, they're gonna read the results at a set time later. No growths, probably gonna get no antibiotic, possibly non-steroidal. Gramme negatives.

Or get possibly non-steroidal, maybe add cream. Some farms, they might get a short, short course. Most of ours, I must admit, wouldn't.

And then gramme positives are gonna get antibiotic treatment. Those treatment protocols need to be agreed and written up. It's really helpful.

If you've got photographs of the test results, so that they can then check when they're getting results, with the pictures they've got. This one is, better repeated, so it shows the different results, that you might get. And it's really important that the treatment protocols, so it is getting a bit complicated, but the treatment protocols need to be individual.

To the farm, it's no good giving them generic, so you should be writing up what their tubes are, what their non-soil is, what those cows are getting. And they need to understand that this is for treatment decisions, not diagnosis. Then if we want to diagnose the actual bacteria that's causing mastitis, then we need to use a, a proper lab.

So this is for making a gramme positive, gramme negative, no growth diagnosis to determine treatment decision. So if there's any issues or strange cases or unresponsive cases or doubt, then we need to use an accredited lab. So what are the critical components to success?

I mean, obviously it's really important that the farmer can make the correct diagnosis. And that there's quite a lot of steps going into that. They need to be able to take a clean sample.

They need to have hygienic workspace where they can inoculate without contaminating. So if there's a wind travelling through and dust on the farm, it's that's not going to be possible. It has to be a fairly clean, clean workspace.

If it's a plate system, they need to be able to store and incubate the plates upside down without excess moisture, and they need to use the tests in date. But making the correct diagnosis is only half of it because they then need to be making the correct treatment decision based on that, which is where our protocols come in. I just want to do a bit of a run through of some of the tests available.

There's a lot of tests out there. This is only a selection. This is the ones I'm perhaps a little bit more familiar with.

But basically there's, they all rely on selective growth media. The earlier ones were sort of basically modified egg plates with selective media for gramme negative. And either one positive or staph and strep.

So this is a better P plate. The pale section, is, is gramme negative. The pink section there's for stas, and the dark red section there's for streps.

This is the Minnesota easy culture system. They have either a by plate or try plate. This is the one that was used in in quite widely in the US.

Petrifil is not something we've used for on-farm culture. It's actually something we've used occasionally for doing coliform counts, but, it can be used perfectly well. I think you, there's one that, will grow aerobic bacteria and there's one that will just grow coliforms, so you can use it, use it that way.

The Vetta slide is another system that was produced by Vettaquinol that also produced, vetalape and I think that was designed to be a bit simpler for farmers to use and a closed system, so a bit better for health and safety as well. And then there's mast side, which is being imported by Vail Veterinary Laboratories. And again, that's a closed system.

So it's just colour change. I think I think it's it's kind of farmers related to the Delva test. So it's fairly easy to train farmers to to to use.

. You inoculate these two little pink tubes, if they stay looking like that, then that's no growth. The one in the middle is a gramme negative, and the one on the right with two whites is gramme positive. Something we've been using this one a little bit, I'd say the only disadvantage of it is no there's no way of recognising contamination.

So you have to be confident that they can take clean samples. And then there's the master test, which I don't think's widely available yet, but it's a New Zealand system. Can't quite get my head around how it works, but it's basically a colour metric system.

So, it incubates the sample in several wells, and, you get a diagnosis via the internet, which actually gives antibiotic sensitivity as well. But I don't think it's widely available yet, just making, making people aware it's out there. So how do all these tests before?

This is a sort of summary, that was carried out by the University of Glasgow, of, of test performance. For me, the important thing. About these tests is the sensitivity for picking up gramme positives.

I want to know that they can pick up gramme positives and possibly there's less specificity for picking up gramme negatives. So most of them are sort of operating in the sort of 80 to 90% sensitive for picking up gramme positives, Mark, they they're. There's a bit of variation there.

Just to look in a bit more detail at how the vet repeat . Performs. This was work done by, Lorenzo Viora at the University of Glasgow.

So he found that for for identifying specific pathogens, it was not particularly accurate. So the sensitivity was as low as 17%, up to 84%, depending on the pathogen. But really, As I said earlier, this is not why we're using these tests.

What we really want them to do is give us treatment decisions. So when, when assessed at the level of treatment decision, the sensitivity was much better, 91%, and the specificity was, a bit lower, but, . Probably not, not so important.

It's the sensitivity for picking up the ones you want to treat. So that's just a . To show a sort of E.

Coli going on the peeled and that's just to show a staff all this, yeah. So, for, for a successful test, as I think I've already said, we can discuss this later if anyone wants to ask questions about it. I don't want to be missing gramme positive cases that would benefit from treatment.

So I want to know that the high sensitivity for gramme positive organisms. But if we combine that with a low prevalence of gramme positive organisms, we can actually end up with a very high negative predictive value of the test. In other words, if test tells you you don't need to treat how, it's got a very high chance of being right.

And I think that for me sums up what where we need to be with those tests. So we need a reasonably high sensitivity and we would like a low prevalence of gramme positives and then we'll get good performance. So problems.

I think Some of these systems, this is a veter plate with with a contaminated sample. So farmers need to need to be able to recognise that. As I said, some of the systems don't pick that up, so we need to be confident that the farmer can take a clean sample.

I mentioned Prototheca here. Protothey is an algae, and it will grow, as far as I'm aware, on all of the media. So if you're getting something funny like that going on, obviously it needs further investigation.

So if you're getting unresponsive cases and it doesn't fit the picture, it needs they need to be checked. Likewise, mycoplasma won't, won't grow, unsurprisingly. So, you know, if we're suspecting mycoplasma, we need to go looking for it, that these systems are not designed to pick these sorts of things up.

Likewise, if we're getting a lot of no growths, more than 40%, probably worth checking the samples just to make sure that there's there's nothing going on that's that's inhibiting growth. And finally, also just sometimes milk clumps can be misidentified as as bacterial colonies. So how do we actually monitor these systems once they're up and running?

How are we gonna tell whether it's on? Whether it's a good idea or not. I think sort of daily monitoring, or not daily, but when you, when you, when you're there, just popping in, how's it going?

It's really worth checking the health and safety aspects that this is that this is being done safely and just have a look at the plates. So what was that one was, do you agree with their diagnosis? Does it seem to be running the way you think?

But I think it's important to come back, preferably quarterly, depends on, on their case rate, and just do a bit more of a review of how things are going. So the first thing that we want to know is how many results have been gramme negative, how many have been gramme positive, and how many have been no growth. Is that what we expected when we started?

It's shifting over time. We can also then look at antibiotic use and we can. Try and have a look at cure rates as well, which I'll go into in a bit more detail.

So, diagnostic results, obviously, if every single case is GAM positive, it's probably not . Not worth continuing. This, this has actually happened on on one farm that I, that I started this on.

Likewise, if the results are changing over time, is that because the mastitis pathogens are changing over time, or is it because there's a problem with contamination or or sampling technique? And Periodically it's worth just taking some of the samples from the freezer and carrying out lab bacteriology and just checking. And that's worth doing on maybe some of the problem cases, but it's worth doing on just some of the random ones as well.

I always like to look at antibiotic use. So has the antibiotic use actually gone down? Because often that's one of the prime drivers from the farmer's point of view.

This is sort of an example of the antibiotic, . Analysis we do within, within our practise. We look at, we, we do benchmarking, with our other clients and we also look at how things change over time.

This is my course, course of antibiotic. And this one is, is tube use. If you haven't got, the, the, means to do that easily, there's also a very good ant microbial use calculator provided by, the University of Nottingham, and it's available on HDB dairy website and you can download it for free.

So you can just put in the farm. Antibiotic use for the year and it will calculate for you what the, what the make the kg have been and what the number of courses have been. So that way, it, you can monitor how the anti antibiotic use has changed.

It's really nice to be able to look at cure rates as well. Looking at cure rates for mastitis on farm is, quite challenging. So one of the simple things to look at is just how many cows have been 3 quartered, how many cows have been culled from mastitis, what's the clinical recurrence looking like, what's the milk somatic cell count?

Is it, has it gone up? Has it stayed the same? Has it come down?

If you've got access to total vet, you can look at the cure rate graph. It, it's quite slow to change, but really worth looking at over the long term on farms that are doing on-farm culture. I've picked here a classic farm with a pattern of mild gramme negative environmental mastitis with really good cure rates, but obviously not affected by, by carrying out on farm culture.

And if you've got companion, then you can just follow them up based on their cell count as well. That's it's just another way of doing it. So, farm selection, .

What you need for this to be successful, basically, or what we found we need for our farms, maybe you'd make it work differently. We need enthusiasm and the ability to follow protocols. We need somewhere where they can plate up their their test kits.

You don't want a high mastitis prevalence, you want mastitis under control. Ideally, a gramme negative environmental pattern with good mastitis detection and some proper clean bacteriology results before you start. You definitely don't need a contagious mastitis problem, poor records, too many milkers, people who can't comply with protocols, and a high stress environment is not gonna work.

And this is definitely not a substitute for a mastitis control programme. This is in addition when other things are, are moderately under control. I say check for maverick tendencies.

I think a lot of the, farmers who this appeals to do quite like to, do their own thing. So sometimes that just needs checking up on, some of our clients absolutely love on farm culture and they would love to be able to run their own laboratory. So they just need to be kept in check a little bit to keep it to treatment decisions following the protocol.

And just check that things haven't slipped, they haven't forgotten or stopped taking clean samples. So when have we found that it hasn't worked, . Obviously contaminated samples, this makes it a complete waste of time.

There's been a couple of farms who've really been unwilling to withhold treatment from cows. And that's maybe, stockmen who've had bad experience with, toxic mastitis cases, and they're convinced that if they withhold treatment, then the cows are going to go downhill. So if they really don't want to withhold treatment, it's, it's a struggle.

Likewise, sometimes there's just poor decision making and they're not treating cows who need to be treated, and again, then they're not benefiting from, from the actual system. Too many workers, it can work, but usually it doesn't. You need one person to take ownership and be able to run this, .

And also circumstances can change. So the mastitis pattern can change, there can be an outbreak. There can suddenly be lots of sick cows and people get very twitchy or staff changes and shortages.

Often these these systems are driven by one person who's very keen if they leave, it might not be quite so popular. And the other thing that I found is that their early experience matter. So it's really worth giving that support early on, making sure it's done properly and that it and that it works early on.

So what does success look like? . In short, Lower antibiotic tube use with similar outcomes, no worsening of cell counts, and less milk thrown away.

And if you can achieve that, generally speaking, you'll have a farmers. So it, it, it suits some farms, but not all. It suits some farms, but not all.

It's really important to monitor. This is not something that we can set up and walk away. But that's a good thing as well, because it increases our involvement with mastitis on farm.

It fits in really well with the drive to low antibiotic use, but that should never be at the expense of, of mastitis control. So just to give, give a picture, I think currently 5 to 10% of our clients are using it. So it's, it's still quite niche, but the ones who are using it are, are very enthusiastic.

. And on board, . I think that's all, that's all I had to say. So thank you very much.

And if anyone's got any questions, I would love to to discuss some of those things further. Thank you very much, Rachel, that was a really, really useful and very practical presentation on this important topic, and we've already got questions coming in. But before we go to questions, could I just ask everyone watching to spare 30 seconds to complete the feedback survey that should have popped up in a new tab in your browser?

Depending on which device you're using to watch the webinar, the survey doesn't always present itself, particularly the case of Apple's. So if that's the case for you, please feel free to email us any feedback, at office atheebinarett.com.

Similarly, if you're listening to the recording of the webinar, you can submit your comments on the website too. So, as I said, we've got questions coming in, we, we've got a good, a good amount of time for them, so please keep them coming in and try to get through them all. So, if we start with the first question that came in relatively early on, in, in the presentation, a question from Corey, just relating to starting treatment, and then stopping it based on results, would this contribute to increased antibiotic resistance in, in your, In your opinion, in, in, in as far as any antibiotic use contributes to resistance, I don't think there's any evidence that a shorter course, would, would lead to more resistance than a longer course in a, in a case that doesn't need it.

So, . No, I don't, I don't think that's, that's an issue at all. The reason why we don't normally do that is because it really does wipe out a lot of the cost benefit of doing on-farm culture.

Because you're, you're then having to, to, discard milk, . And also, you know, if you, you're trying not to treat cows, you've sort of undermined yourself at the first hurdle. OK, thank you.

And the question again, that came in, halfway through, I think in response to the, the graph, that you showed of hide at Al that showed the amount of antibiotic usage. A question from Andy, do you think that some of those herds that have the very high antibiotic use, could have been those using long tube courses and concurrent injectable antibiotics inappropriately or even for all cases? And what's your thoughts that maybe these could reduce antibiotics hugely by treating cases more appropriately and not tubing until clots go on all cases?

Absolutely. I mean, those, those herds all need to be looked at. To see why their usage was so high.

But I think the, the more I, I quiz farmers about, about their treatment regimes, the more I realise that there's some very strange things going on out there. And definitely, if people are using incredibly long treatment courses and injectables, they're just not going to get the benefit. So it's a really easy place to start.

Yeah, for sure. Brilliant. We've got a couple of questions here as well about high cell count cows and sub-clinical cases.

I'll amalgamate the two. Do you have any experience of farmers using, on-farm culture for high cell count cows just because they, they have the facilities there to do it? And what's your advice surrounding that?

And do you think it's an option not to treat any subclinical cases at all? Would you just focus on the clinical mastitis? OK, so we don't encourage, well, we actively discourage our farms from using it for subclinical cases.

First reason would be then that's not what they're validated for. You've got a much higher, higher chance in your subclinical cases of it being a gramme positive. You've got a much, yeah, the, the, the system's not designed for that, basically.

And these, these farms, are not gonna have, high sale counts. So they're not gonna be on that borderline of, of, of going into penalty bands and whatever. So generally speaking, if you treat a subclinically infected cow with antibiotics, you're gonna get a very disappointing cure rate.

That's just a fact of life. So, in my book, if you don't have to do that to get your cell counts down, I, I would wait until they're dried off. They're, they're, they're gonna cure much better at drying off.

So we wouldn't, we wouldn't recommend the on-farm culture for subclinical cases. And I generally, in those farms that are doing on-farm culture, wouldn't recommend treatment of subclinical cases either. Fantastic, thank you, great answer.

So just a couple of quick ones here. You mentioned the veto slide test. Have you actually had any practical, experience of using that?

No, and I, and I, I have some and I keep meaning to play with them. Yeah. Well, I think we have used it within our practise, .

So I can't comment. I can't comment. I just know it, it was designed to be a simpler system and and an enclosed system.

. Yeah. Brilliant. It's on the to do list.

Yeah, it is. Another question here, actually two very similar questions, relating to NSAID. So, is there any trial work that's been done that compares cost benefit of on-farm culture versus blind conservative treatment, for instance, an NSAID of non-sick cows and herds with high gramme negative, but low gramme positive prevalence.

And that also sort of links in. To the other question, which is, would you treat a cow with an NSAID while waiting for results to come back? Oh, absolutely, yeah.

I probably didn't make that clear. So nearly all our farmers who are doing this would be giving a zero milk withhold NSAID, on day one. So that works beautifully with this system, because it doesn't affect milk milk withhold, and the cows getting treated.

Does that answer the question? There was, was there another part to it? No, it answers two in one, so that's great.

Another quick question. What's the rough cost per sample? This is Annie.

Oh, so the cost of the test kits varies quite a bit according to where, which one you get and where you get them from. Anything from, I think the cheapest, if you were importing some of the cheaper ones, would be from 2 or 3 pounds up to 889 . We might even be going up to 10 for some of them.

So there's quite a big variation, so that's worth looking at when you're making the decision. And adding into that cost, how long does it roughly take, say, for instance, in farm staff time, because that is a cost to both run and analyse the sample. I mean, it, it sort of depends how the farm's set up.

I mean, some farms, they seem to manage to take, a sterile milk sample pretty easily during milking. Others, it's more of a palaver. It's really a few units, max.

I mean, the plating up is very, very quick, . I mean, the important thing is to take the sample during milking, but then do the plating up, you know, after milking when things aren't rushed and they can be calm and clean. Great.

OK, sorry, just going through some more questions here. Keep them coming in if you've got any more that have cropped up. A question here from Ben regarding a Canadian study that you mentioned, where low sample volumes resulted in poor accuracy.

So would you have any comments about how many tests someone needs to be doing to get good and well practised or can this be circumnavigated with good training? That's a good question. And I'm not sure I know the answer.

I mean, that trial, they were really, they were getting literally one case a month, which is pretty infrequent. And, I mean, I think as long as you're doing one a week, it's not gonna be an issue. I think, I think you just have to play that one by ear.

It doesn't, it, it depends on the individual, doesn't it? But it definitely is an issue, and it's not something we can ignore that if, if that. Some people carry this out better than others.

And if they're not doing it very often, they can forget. But then if they're doing it frequently, you can get a mission slip as well. So even the guys who are doing it all the time need just the odd refresher and just check that they're still doing it right.

And following on from that about refreshers and things, you mentioned about monitoring, could you just expand on how you do your carry out your monitoring of herds and what factors influence how often you monitor and what you carry out when you do your monitoring? Oh, goodness. So, yeah, I, I better be careful saying what I, what I would mean to do and what I actually do.

What I mean to do is I, I, I go in there 4 times a year and I look at their, cure rates and I look at their antibiotic use, and I look at their, their incidence of the 3 categories, and I ask them how it's all going. . I have to be honest, sometimes when people are extremely happy with how it's going, you get more resistance to, to look at it.

I, I was on a farm today, and, they, they'd had, since, since the last time I was there, they'd had 1 gramme positive and they'd had a lot of gramme negatives and a lot of no growths, and they were extremely happy with the system. So it was hard, it's almost harder to get in there and analyse things because they were, they couldn't see the need. But, But yeah, I'd definitely do something quarterly.

I've got everyone in my diary to to touch base and check. Yeah. Great.

And I think following on from that, you did touch on some of the pitfalls, but have you, have you ever suggested to a farmer that they actually, stop on farm culture? And what reasons, what are the main reasons behind this? And how do you, how do you navigate that when you have someone who's really sold on it and wants to, wants to carry on?

Oh, that's, yeah, it's a good question. So I think most, we, we've had farms who've stopped doing it for sure, but it's mostly been a, it, it, it's mostly a mutual or, or they don't want to carry it on. I'm not sure I've had any that I've said, I think you really must stop that now.

And they want to carry on. But the reasons, have been, mostly, . Too many gramme positives, meaning that they just weren't getting the benefit.

One farm, they were twitchy. They, they, they thought they were getting too many sick cows, and so it made them extremely twitchy about withholding treatment. And other farm.

It was just labour. They were, they were short staffed and stressed, so they stopped, which was understandable. Some, some farms will just suspend it at, at difficult times, and then come back to it.

I've had that happen as well. I must admit I, I haven't, maybe I should have, I've never actually said to somebody, I really don't think you should be doing this. That would be awkward, wouldn't it?

It depends. It depends, I suppose, if they're ones that really want to carry on or not. Usually you say, I'm not sure.

I'm, are you, are you getting the benefit, you're not really getting the benefit, are you? And they say, no, do you wanna stop? Yeah.

But, you know, and it's a sort of discussion, mutual discussion. I think just, another question that's come in, which it sort of ties in with the the questions around monitoring that we, we just had. How often do you recommend that samples are sent off to a good lab for quality control to check accuracy of their tests?

You mentioned this during the presentation, but do you have a set, a set frequency for doing this? No, I don't, and I probably should. But definitely when people say I'm getting recurrent cases, then we, we will check those.

We probably should send just a handful of . Regularly, but I must admit I'm a little bit more haphazard than that. So we tend to send off, the, the problem ones just to see what they are.

OK. And another one that's linked, I suppose, into the high sell count cows. But do you, do you see on-farm culture possibly being used for cull decisions, particularly regarding staff or for high sell count cows, i.e., conducting, the culture before serving?

Do you think there's any benefit there? Yeah, I mean, some of these, some of these systems are, I, I didn't really talk about that because it was getting too complicated. Some of these systems have ways of identifying Staph aureus, and they sort of, you can train the farmer to spot Staph aureus.

So it's, it's a possibility, if you've got someone very keen. Usually I would just recommend using an accredited lab for things like that. But some of those systems do have the ability to do that.

But your, your, your rate of, of, finding stuff always in a subclinical cow is, is, is, as I already said, it's gonna be disappointing, so. I don't know how, how accurate that would be. OK, so maybe one not to to pin all your, all your hopes on, but maybe is in conjunction with other, other things.

Yeah. OK, we're gonna finish up with a final question from Tom. If predominantly gramme negative cases, from routine surveillance bacteriology, are results from on-farm culture sufficiently better than just treating everything with NSAID without culture to justify cost and labour of on-farm culture?

Yeah, that's, that's a good question. I mean, we, we've had a farm that's actually done that, I think, with, with success. But you, I'm just a little bit nervous because things can change.

And if things do change and you miss it, you've suddenly got a big problem where before you had a small problem. So, You you'd have to be confident that it was all gramme positives and it probably isn't, isn't going to be, but certainly . It, it's been done.

But you still need to do some form of monitoring, so you can't just, you can't just say, oh we're gonna save all that money on on-farm culture because you still really need, that's quite an extreme thing to do, so you need to be monitoring it quite actively. OK, that's brilliant. OK, and that brings us to the to the end of our questions.

We've managed to get through an awful lot of questions there. So thank you, thank you very much. And it was absolutely great presentation, loads of practical content there, and we've had some fantastic feedback coming in, people saying, great presentations, thanks, a really thorough overview of, going into all the detail about on-farm culture.

So, thank you very much, again, Rachel. And to everybody who's listening, we really look forward to you joining us again for the next BCVA webinar. We are holding them, every 2 weeks at the moment.

The next one is on the big data revolution and the cattle bets, and we've got Chris Hudson from Nottingham University joining us for that. So we really hope to, see many of you, coming in and joining us again in two weeks' time. But in the meantime, thank you very much, Rachel, once again, for a great presentation, and to everybody who's been listening, thank you, good night, and stay safe.