Baa's and Bleat's - The AASRP Podcast
Baa's and Bleat's - The AASRP Podcast
Setting Up for Success - Dry Period Considerations
On this episode we sit down with Dr. Joan Dean Rowe from the University of California - Davis and Dr. Roselle (Rosie) Busch from the University of California's Department of Agriculture and Natural Resources to discuss strategies for maintaining and improving udder health during the dry period.
Topics of conversation include a basic overview of the physiology of a goat's lactation and dry period; discussion of dry-off protocols and considerations for which strategy to apply to a given herd; the National Mastitis Council's Five-Point Mastitis Control Plan, its effects on the bovine dairy industry, and how it can be applied to dairy goat production; considerations for intramammary dry-off antimicrobial use in dairy goats; overview of the Iowa State University/UC Davis dry tube research project.
Helpful Links:
National Mastitis Council's Five-Point Plan: https://www.nmconline.org/2018/02/06/nmc-speakers-address-the-five-point-mastitis-control-plan/#:~:text=NMC's%20five%20points%20include%3A%20post,maintenance%20and%20culling%20problems%20cows.
Order form for the Dairy Goat Production Handbook (Langston University): http://www.luresext.edu/sites/default/files/DGPHorderform_1stEdition_case_spiral.pdf
This podcast is sponsored by the American Association of Small Ruminant Practitioners as well as USDA National Institute of Food and Agriculture, Agricultural and Food Research Initiative Competitive Program, Antimicrobial Resistance grant # 2020-04197.
Questions or comments about today's episode can be directed to DairyGoatExtension@iastate.edu
Hello, I'm Dr. Michelle Buckley from Iowa State University's College of Veterinary Medicine. Thanks so much for joining us on Boz and Bleeds, sponsored by the American Association of Small Romant Practitioners. Just a quick note before we get started. This work is also supported by the USDA National Institute of Food and Agriculture, Agricultural and Food Research Initiative competitive program, a TMI-COVID resistance grant number 2020-04197, which funds my research on improving antibiotic stewardship in dairy goats to assure food safety and milk quality. As always, if you have any questions about any of our episodes, please email them to dairygoatextension at iastate.edu. I hope you enjoyed today's show. Thanks for joining us today on season one of Boz and Bleats, the American Association of Small Ruminant Practitioners podcast. This season we are focusing on improving milk quality and food safety in dairy goats. Today's guests are Dr. Joan Dean Rao of the University of California, Davis, and Dr. Roselle Bush, Sheep and Goat Veterinary Extension Specialist for University of California's Department of Agriculture and Natural Resources. Today's topic is setting up for success, and we're going to be talking about keeping udders healthy during the dry period. Let's start off with some introductions. Dr. Bush, you're new to the podcast, so can you give us a little bit of background on your involvement with dairy goats and your career?
Rosie:Yeah, so I, as you said, am the sheep and goat extension specialist. I actually work at the School of Vet Med, but I have a statewide position through UCANR, and it's been amazing. I've been doing this for three years now. Before that, I worked with CDFA for two years, starting their antimicrobial use and stewardship program with a great team. And then prior to that, I've worked at UC Davis in our livestock medicine and surgery service. So did internal medicine, a lot of great individual animal medicine with production animals as well as companion livestock. And yeah, so I've been working with livestock for over 10 years.
Michelle:Awesome. Well, welcome to the show. Dr. Rao, you were here on our second episode that we called If You Can't Measure It, You Can't Manage It. So I'm sure our listeners are already familiar with you, but maybe you could just refresh our memory with a little bit of background information.
Joan:So just very briefly, my name is Joan Dean Rao, and I'm a veterinarian, now a professor emeritus at the University of California, Davis, after retiring with after a 30-plus year career in livestock herd health and reproduction, where I work with all the livestock species. But as most of you who know me know, I have a real special love for dairy goats and a lifelong interest in dairy goat health. I also breed tog and bird dairy goats.
Michelle:All right. So to get started, we're going to start with the basics. And I just want to talk about what a normal goat's lactation looks like and how much variation is there. Obviously, there has to be some with the wide range of breeds that we see here in the US and internationally. So, Dr. Rao, can you kind of give us a broad picture of that maybe?
Joan:So just very briefly, the um I guess the first thing would be to appreciate that the natural tendency for the goat would be to be uh seasonally um uh to have a seasonal of estrus. So the natural kidding period would be more in the spring months in our hemisphere. And then uh the highest proportion of those would be dry than in the winter months. And many dairies have schemes to um manipulate the reproduction to have year-round milk supply and year-round kiting. But um we have not just the lactation curve, but then also the seasonality of reproduction that layers onto how we manage dairy animals and kind of the expected um periods of low production or dry periods. Within the individual goat, again, there's going to be a lot of variation, more based on as much management as breed, but the typical goat lactation, we can use sort of the standardized um 10-month lactation, two-month dry period with an annual cycle of kitten. Um, appreciate that. Uh, and many dairies, there's selection for um extended lactation so that a doe may stay in lactation for more than one year until her successive kidding. And that would be through selection of those animals that have the um persistence of lactation to be able to do that. And that the the annualized curve would be, you know, very similar to the dairy cow in that there's a peak. Um, again, it varies on breed and management, but a peak maybe six weeks after kidding, and then a gradual decline. And where there's been less intensive selection for production, then we might see a more precipitous decline or a steeper curve or steeper reduction in in production, and that presents some challenges in keeping those doughs in year-round milk.
Rosie:And it's really interesting. There's I kind of went down a bit of a rabbit hole when reading this. And um Dr. Mondini had shared some of their lactation curves that because they do daily milk weights, um, and just seeing the variation of those peaks and the slopes of those peaks, even on one farm that has the same management, is really interesting. And it prov it poses a challenge for management, especially with nutritional management, when if you're feeding everyone for peak lactation, then you may get some overconditioning of those and some more metabolic disorders. And so it's really interesting in Europe they seem to be going towards more individual precision nutrition, where with daily milk weights, they have these collars where they go into these feeders and they're given the right quantity of feed for their milk production at that time. So it's interesting that there is some research going into that on European dairies, but those dairies are so different from ours. And so that research is really challenging to, and even their nutrition, like the feeds that they're using, are so different. But it is interesting that that work's being done. Um, but yeah, just shows that the I don't know, the variation of lactation uh curves is not only challenging for your milk supply, but it also impacts your nutrition management, your input, and all of that. So yeah, it's kind of a neat tangent to go down.
Michelle:No, absolutely. I think that's important to note because I think most farms will group their doughs by where they're at in lactation with the expectation that they're all gonna peak around the same point in their lactation. Um, and so you know, backing up into like feeding them the same and expecting that that's an appropriate assumption. But um I think it's important to realize that that's not necessarily the case. And so um tracking those daily milk weights can be incredibly helpful, and that might help some farms to rearrange the way that they're housing their animals and feeding them. Um, that's a great point to bring to light. So I appreciate that rabbit hole. I'm sure too.
Joan:I would add one comment, and that would be that even on farms who are unable to have daily uh milk weights and real-time management, that um even the monthly weights that one can get from a standard Gary Herd improvement testing system, or even less frequently, obviously, the more frequent, the better the quality of information, but that information is really key to managing all elements of production, and that uh again, even your monthly weights are still going to give you a lot of useful information.
Michelle:Absolutely. And I know we talked about that more on our uh previous episode, Dr. Rao. So if listeners haven't heard that one, they need to make sure they go back and take a listen. Um, but today, like I said, we're focusing on uh dry period um other health. So I really want to go back and talk about um you mentioned that some doughs or some farms will elect to do like a long uh an extended lactation versus sticking with the standard 10 months milking and two months dry. So can we talk a little bit more about how producers might decide when to dry a dough off?
Joan:So um it will depend basically on two things reproductive status and production. And it all starts with reproduction. So um the decision to breed a doug or not is the one that you would make in trying to determine if you want her to have an extended lactation into milk for more than one year. And that would be based on your knowledge of her production and whether it looks like her lactation curve will carry her through an extended lactation. In um the reproductive status, once I try to decide to breed her, I need to know she's pregnant and know exactly what her next kidding date will be. Then in order to be able to prescribe a dry period for her, which would be customarily approximately 60 days. Um we know from uh dairy cattle that a shorter um period can be achieved. But um, as we get uh too short, then we'll have some lost um production and subsequent lactations. So so the knowledge, exact knowledge of her reproductive status, both in deciding to breed her for extent whether we want to breed her or not, and then second, to know her due date and confirm her pregnancy date so that I can give her an accurate dry period.
Rosie:Yeah, and I so I think there's gonna be some different reasons, like Dr. Rao mentioned, for reproductive reasons. For so you have some producers who are high genetic merit and are breeding annually for kid production so that they can sell high genetic value offspring. Um so they're more likely to want to breed every year and dry off on that more annual cycle. Um, when you have you know commercial berries that are push wanting to do more persistent lactations, they're going to rather than having everyone try to have you know the same length of lactation and everyone dry off and kid at the same time, they're gonna want to stagger those so that their kidding facilities are kind of less impacted. They're not all kidding at the same time. That's one of the neat benefits because kidding takes a lot of labor. Um so it's it's you know, kind of having an idea of ideally who you would be kind of drying off in what sequence, but then again, what her milk production is versus her feed intake, those sort of things might play in. Um I remember talking with Dr. Montini about how you might have a goat that you know is only producing six to eight pounds, but she's been at that level persistently and you know has been very healthy. That may be one that you'll keep in lactation, but again, you have to plan ahead. So I think there's a lot of different factors that'll go into play for who is going to be dried off. And there's probably also other health factors. So if she has been struggling with mastitis, um, that may be one that you might decide to breed and give her a dry period to recover.
Michelle:Yeah, I do know that there's um a farm here in Iowa where, and I'm sure plenty of dairies do this, but they dry their doughs off in early November and um into December to avoid having to milk during the holidays.
Rosie:Yeah, see all kinds of reasons.
Michelle:Exactly, exactly. So I guess the point is, as um has been the case a lot on this podcast, it really depends on your specific farm, but um these are some things to consider um when we're talking about having a dry period. Um I do want to talk about why it's important to give does a dry period or any milking animal really a dry period between um lactation and then having a kid, because there's a lot of really important physiologic and even um microbiological reasons and changes that are happening in that udder during the dry period. So, Dr. Rao, do you think you could um start us off with that discussion?
Joan:Sure. So um the I see the dry period actually as the beginning of the next lactation. And so the involution of the udder or as the um alveoli or the milk secreting units in the udder, then um uh atrophy and then are replaced by new cellular development as she um develops the udder uh with the start of the oncoming lactation. Largely the ductal system remains and the the alveoli or the glandular secreting tissue then um it really is a is a new start to the next lactation, and so it's necessary then to achieve peak production for the subsequent lactation. So I think it's really important to think of the dry period as actually not the end of the last lactation, but the start of the new one.
Rosie:I just kind of looked into this a little bit before we talked, but how throughout lactation production depends on mammary epithelial cell turnover. So the rate of new cells differentiating and becoming lactating cells versus cell death. And that rate really slows down by the end of lactation, and so that's why we tend to get lower production. And then that dry period allows for those MECs to differ, you get a higher population, you get more differentiation. So at the start of a freshening, you have all of those cells ready to go. Um, and it even angiogenesis occurs, you get new, just new blood capillary formation and just more efficient nutrient exchange. And without the dry period, they've looked at this in goats. I actually found a paper on goats, which is amazing. Um they've shown that you can get it's really challenging to keep goats at the end of gestation continuously lactating, but they you can do it, and you can get you get you do get production losses in the net in the next lactation, but it's not as severe as what you would see with cattle. Um so because they do they do still have cell turnover, they do still have blood capillaries, but I think if we did that over and over and over again, that's where you would see, because the population of those mammary epithelial cells continue to decrease without that dry period, because you really need that kind of continual development of those cells. And then yeah, it gives an opportunity for colostrum to develop. And we know that that really starts a couple weeks before kidding. And if we're continually um milking, or we have the dough in continuous lactation while she's trying to develop and concentrate all those antibodies and white cells and all that important um nutrients, all of that good stuff for the new kids, then we kind of dilute that. Um we don't get as great production of colostrum as we should. Um, and I know that that probably has different impacts on different farms depending on what, like in your last podcast you recorded, what type of nutrients and colostrum that they're feeding to newborn kids. Um, but again, so there are production impacts and it will also impact the quality of the colostrum.
Michelle:So we're kind of uh closing the floodgates for a little while to allow the really good stuff to um to accumulate in the udder, and then when we start milking them again after freshening, we're opening the floodgates, and that really um nutritious colostrum can come on out. Um one thing that I do think is also important to touch on is um the natural immunity of the udder during the dry period. Um, and I just am wrapping up a dry cow project where I had to really look into this. Um, but there's naturally a keratin plug that forms inside the end of the udder or the end of the teeth once um lactation has stopped. Um, and in some in cattle anyway, um, which is really most of the data that we have to go off of, but how long it takes for that plug to form can vary widely. It can be from a few days to um most of the dry period. And so the point of that plug is to basically seal off the tea orifice, so preventing milk from getting out, but also preventing bacteria from getting in and kind of preserving the microbiome of the udder while it's going through that involution process. And so, in animals that have a delayed onset of that keratin plug formation, those are when we can especially see intramammary infections that develop during the dry period. So part of what we want to talk about today is mitigating those infections that can develop during the dry period and also managing those that are present while we're um drying animals off.
Joan:Yeah, where I thought you were going on the keratin plug uh comments was the importance of um monitoring those doughs once they go into the dry lot, because for those with the slow plug formation, then you might want to be teat dipping those and continuing to monitor the udder health by palpation. And for um and as we talk about um infusing the udder, how it the trade-off between uh having an antibiotic in the udder versus disrupting the street canal and potentially the keratin, the natural house defenses like the keratin plug by our infusion. We would assume that we're disrupting if we disrupt, especially a full cert full insertion of a mass tidis treatment tube, for example. Um, partial insertion will help disrupt the avoid disrupting the street canal. But I I would assume that either anything that both either disrupts the street canal or where you have excessive intramammary pressure, such as a dough that's bagging up as as we try to turn her dry, that that those would both compromise the host effect, you know, it would do it would impair her ability to um to to keep out bacteria.
Michelle:Yeah, that makes a lot of sense. And like you said, there we need a lot more data on this and and to look into it a lot further. But um yeah that keratin plug can be affected by a lot of a lot of aspects. So another thing that I found while I was doing some research from this podcast was um just looking into why we've started utilizing um dry cow treatments in the the bovine dairy industry um and to just kind of try and extrapolate that into the goat industry. And so back in the 60s um there was a five-point plan that was developed and you can read about this on the National Mastitis Council's website if you're curious. But basically the goal was to improve milk quality in the American dairy cow herd. And so the five points were to document and treat clinical cases. Post milking teat dipping was really important and not being universally utilized. Dry cow treatment dry off was a part of that um call problem animals and then perform regular milking equipment maintenance which Dr. Rao has talked about with us on the previous episode as well but just making sure that we're you know cleaning and sanitizing after every milking replacing parts as necessary which Dr. Mongini talked about in her somatic cell count episode so all of that regular stuff really contributes to utter health and overall milk quality. So one thing that I wanted to look at when I was preparing for this podcast on top of that five-point plan was what changes have we seen in the bovine dairy industry since implementing dry cow therapy? And obviously there's been a lot of changes in the dairy industry since the 1960s and we can't possibly attribute them all to implementing dry therapy treatment but I do think it's safe to think to say that this five-point plan has contributed a lot to the decrease in severe contagious mastitis pathogens that we find in our herd now like Staph aureus and strep agolactea in cattle. We've also significantly increased our milk yield for the bovine dairy industry per cow the annual average in the 1960s was about almost 38,000 pounds of milk in the 2010s that average jumped to 101 almost 102000 pounds of milk. So we're seeing significant improvement in the amount of milk that's according to the FAO stat um database that you can you can find all of that information. You can also find on the NASS website that we've seen significant decreases in the somatic cell count of the American dairy herd over the same course of time. So I'm sure that's not all attributable to dry cow therapy but all of these five steps that we've been taking to improve milk quality in cattle definitely appear to have been paying off. And I think our goal with this podcast and with the research project that Dr. Bush and I are working on is to emulate that in the dairy goat industry.
Rosie:Yeah I think one of the big challenges and differences maybe not total difference but I think one of the challenges is that we do have a lot of or not we have contagious pathogens that don't respond to antibiotics like staphorius and mycoplasma and I know Dr. Rao wanted to talk a little bit about those but I think the value of what we're doing with the research that we'll talk about a little bit more is to look at those subclinical mastitis pathogens and how these dry therapy procedures may help improve milk quality milk production since it is you know they're not clinically affected. And even with our contagious mastitis it's they those persist in the herd without severe clinical signs. So they're they're really challenging to identify and so dry therapy is one thing to look at for improving milk quality and milk production but it's certainly not the full picture.
Joan:Well actually I I think you um remarked on it very well in that uh if we if we're just talking about dry therapy that there's a category of incurable infections that require a completely different approach. And so relating back to Dr. Budley relative to the five point that um culture and identification of the organisms you're dealing with teat dipping in in this case I'll throw pre-and-dipping uh in that the I think when that plan was made the pre-dipping was less um known as a strategy for environmentals but um the teat dipping the utter hygiene the diagnosis all those things and culling that um I think both of you said it really well that um that that but but to recognize the importance of chronic staphorias and the importance of mycoplasma especially mycoplasma mycreates catheter in um as an endemic uh organism in the herds and and that's not addressed by dry treatment.
Michelle:Absolutely I just don't think that we can overstate the importance of culturing um especially those that have chronic issues with mastitis um and even doing bulk take uh samples which Dr. Manjini talks about in her episode um and so we can identify if we do have one of those contagious pathogens in the herd and start utilizing all five points um of that plan to eliminate the issue so we do need to be calling problem dose um if they're shedding staph aureus into our bulk tank and spreading it to everyone else in the herd um we need to be aware that that's a problem and who has been affected and make sure that we're keeping them separate from those that are not affected so that we can work towards a a staph aureus free herd same with mycoplasma because bacteria or antibiotics like you said are just they're not going to cure that problem. I was wondering if we could hone in a little bit um for the sake of discussion on what the different strategies are for um dry period intervention. So if we're going to use antimicrobials versus not use them andor maybe using them in a selective manner and maybe we could touch just briefly on pros and cons of why we may or may not want to utilize that program on any specific operation.
Rosie:Yeah so the main I think historically the main strategy that was promoted especially in dairy cows with blanket antimicrobial therapy I think there's a lot of reasons for that one was a lot of we didn't know so you kind of mentioned with dry therapy we could be addressing current infections in the udder that we want to resolve prior to the next lactation or we could also be preventing new infections within that dry period for an udder that might be predisposed to getting infections. So that blanket dry therapy was meant to cover all of those faces and for management reasons I think for folks that weren't doing any kind of intervention before this was probably a more practical approach. Now in especially in dairy cattle there's more research looking at how we can identify animals that either have current infections that dry off or who might be more susceptible to new infections that would be identified in the next lactation. So there are algorithms there are there's the kind of the the culture and treat strategy for selective dry therapy and then there's even more complicated algorithms that are looking at um milk weights uh somatic cell counts all kinds of um utter scores like there's all kinds of things being done in dairy cows and I don't think we have a gold standard for it yet but there are a lot of dairies practicing culture based dry treatment um and so it's there's a lot of opportunities for kind of investigating that area and learning when which animals would benefit from antimicrobial therapy at dry off. But yeah without knowing that if there seems to be the a great risk of in current infections or new infections that's where the blanket dry therapy fits pretty well.
Michelle:The way that I've been looking at it as I kind of dive into this is that we've seen such an improvement in milk quality on the bovine side since we implemented blanket dry therapy and now we can kind of back off a little bit and say okay we've mitigated a lot of these problems so um maybe we can be specialized. And of course we you know our judicious use of antimicrobials is always important in front of mind um on farm and as veterinarians um so I think that's a tough thing to balance with just having so far to go with milk quality in general.
Rosie:It's really interesting when you look at judicious use principles. Intrammary therapy is really great as far just kind of in general as you're looking at all antimicrobial use because it's localized infusion of antibiotics to the site that's either infected or has a high risk of infection. So just starting with that I think that's a great place to start and then to become even more strategic about our approach to administering antimicrobials is great with kind of evidence-based information that we can get for making those decisions.
Joan:I think that um both of you made really good points about that that kind of decision and precision um I kind of wanted to take uh the 10,000 foot view and remind everyone that um you know hopefully through some of this work maybe more medications will become labeled for goats but that um even whether it's blanket or selective we're really in extra label use of medications and that comes with a certain set of requirements in both record keeping diagnosis and monitoring in order to be able to prescribe these treatments which involves our knowledge of the herd and the organisms that are in the herd even even if we don't have the individual animal data for each animal we're treating especially in a in a blanket situation or just a high semitic cell count situation. And that that in for example with the with a blanket treatment then it's you know no goat left behind. So you you know that everyone's getting the treatment and that everyone's being treated the same so you know that that management is being applied uniformly. And so that's an advantage. The um disadvantage comes back on the reproduction end if a goat aborts or she's really not due when I assumed she was due without having reproductive ultrasound backup or other knowledge of her true reproductive status than that in addition to the increased cost of medication I'm adding risk in terms of residue if I don't have a perfect understanding of a reproductive status and end up with a residue because she kitted earlier than expected or aborted and so on. And um and then further along those lines our world has changed relative to our concerns about antimicrobial resistance in a broader sense, not just in the farm for this organism where as Rosie said this is very kind of precise it's local it's at a very prescribed point of time and so on. So that's that's quite favorable but you know our world has changed relative to our awareness of the total use of antimicrobials and how judiciously then to to um to parse those out. So that favors the selective approach and the selective approach again requires a great deal of management identification records diagnosis in order to know which animals to target to both reduce cost and reduce risk of residue.
Michelle:There's some really intensive management involved in selective dry therapies and I think one of the biggest challenges for that on the front end is that a lot of producers just don't have the resources to be able to accomplish that. Whether you're going to be doing somatic cell counts on your animals and utilizing that as your indicator of whether to treat or if you're going to be culturing everyone those are pretty labor and cost intensive potentially especially if these animals need to be you know financially earning you know earning their keep it's hard to factor those expenses in on top of just you know feed costs and general maintenance and stuff like that.
Rosie:I'll just add antibiotics of the tubes are not cheap either. So if you've been getting along without doing any dry therapy at all, you're really gonna want to know that there would be a benefit to implementing either blanket therapy which is more costly and then selective therapy which is less costly from an antibiotic point of view but probably more costly from a labor and management point of view. So yeah there I think there's you you want to I think that's where this project has a lot of value is showing if there is a benefit to milk quality and milk production with the implementation of these strategies.
Michelle:And I think Dr. Monjini in in her somatic cell counts episode gave us some great tools for potentially identifying high-risk dose that would benefit from antibiotic treatment utilizing that California mastitis test and that algorithm that she presented in that episode could be a less expensive way for producers to start implementing a selective type program I I agree that it's you know it it you may not have individual animal culture data, but hopefully you have herd culture data so you can predict the most likely organisms.
Joan:And so you do need culture data at least on the herd so you know who the who the familiar faces are that you might be you you might be dealing with.
Michelle:And really it comes back to having data on those animals um on those metrics before we get to the dry period. We really need to be tracking that throughout the whole lactation to understand if there's been a deviation that could indicate an infection or if it's just increased kind of along a natural or normal curve that that is just indicative of you know being ready to dry off. And I I feel bad drawing parallels between the bovine industry because the goat industry dairy industry is just so different in so many ways but sometimes we kind of have to utilize the data that we have in front of us and this is you know the closest thing that we have but I recently finished up a a project working on dry cows and dry cow treatments and in reviewing the data for that I saw that you know project similar projects have identified cure rates of up to 90 to 95% when using blanket dry cow therapy and similar for targeted therapy I believe. And then as far as new infection rates so we talked about we're hoping to cure existing infections but then also prevent new infections. And so we can see new infection rates of 20 to 30% in some of these studies that appeared to be bacteria that were should have been hypothetically susceptible to the antimicrobials that had been used for the dry treatment. So can either of you comment on um cure rates or new infection rates that you've seen or heard about in goat dairies that are utilizing dry-off therapies?
Joan:Yeah I I don't have um specific information on cure rates but what I would say is that knowledge of what kind of organism you're dealing with would be really important at interpreting those. So it's probably likely to vary a lot farm to farm. So for example a superficial infection with a duck dwelling organism would be likely to have a relatively with a susceptible bug would be likely to have a high cure rate. And conversely chronic infections with staphylococcal organisms either the staph aureus or the not coag negative staphs which can result in very high somatic cell counts would be less likely to have a cure a high rate of cure. And so you know they they're in they invade the parenchyma there so even if they're susceptible to the antibiotic the antibiotic may not necessarily get to the site of the infection. So I I would I I think one has to be really cautious in interpreting data by knowing what's on your farm and then what what the what the when comparing that with published literature about infection rates.
Michelle:And also there I think there's something to be said for which drug we're utilizing because there are different options and Dr. Bush and I our project is evaluating two different um dry cow or dry off antimicrobials so there's cloxicillin and then there's cefapyrin and so we may see some different um effects based on which drug we're using on um on any given farm.
Rosie:It seems like people are either doing it or not and so really without being able to look at kind of either the culture data or look at their you know before they implemented therapy or what was a reason for implementing therapy it would be hard to kind of draw real conclusions from those or more like anecdotal um and you know I think some folks wouldn't dare dry goats off without it um but it seems like a majority aren't practicing dry therapy. So I you know I I think we have so much to learn.
Michelle:Absolutely and I mean there are other ways that we can mitigate these health concerns utter health concerns during the dry period right so um before we uh started chat before we started recording we were talking about biosecurity um and what were the other methods that you were talking about Dr. Rao for maintaining utter health without necessarily Having to um infuse an antibiotic into the teeth.
Joan:Yeah, so um a couple of things, and before I kind of pivot in that direction, I wanted to make one comment, and that is and be sure that by administering a dry treatment, you don't initiate a new infection. And so the proper technique in infusion would be would start with a um a complete emptying of the gland, and then um my preferred method is to teat dip and then dry off the teat dip, and then prepare the teat end with the alcohol um pledget that comes with the product and continue to clean that until you see no more color and no more debris, and then infuse the product without touching the tip, and only by inserting it as far as needed to infuse the product. So a shallow insertion, again, not to dilate the teat orifice any more than is needed in the street canal, and then to um teat dip then afterward. And there are things like wearing a headlamp so that you can actually visualize with light the teat end while you're working and avoiding hair, and um, you know, it's not uncommon for a dough to stomp her leg or so on and then recontaminate the teat end or potentially your tube. And so it's um again, this is you you have to be ready to discard a tube that's kicked out of the hand or in some way becomes contaminated, lest you um it initiate a new infection by an organism that's not sus, you know, that that is a resistant environmental organism. So, so um having that that um hard and fast rules about how you're gonna handle contaminated tubes, how you're gonna handle the teats. And then to get back to your point, um, once a dough is in the dry lot, um, monitoring those doughs, either through running them through the barn and teat dipping until the udders, you know, become slack and palpating the udders, even just walking and being able to see uh utter imbalances or you know, asymmetry, um, swollen glands, uh, animal, being able to detect changes in during the dry period is really important. And it sounds very labor-intensive, but it's really a matter of raising your awareness and taking a quick palpation where needed, and then managing those dose who are difficult to dry off.
Rosie:And I think your point about utter hygiene is really important. I would just only add that I've seen really bad gangrenous mastitis in those that had the wipes that came from a container and they were left in the barn and had dried out, and they got no cardiaomastitis. And you know, because what we thought was disinfecting the other wasn't, and may have even been introducing infection. Um, so really, you know, like you mentioned, those wipes that come with, you know, individually or knowing that they're saturated with an antiseptic, um, it's really important.
Michelle:Yeah, and even, I mean, going so far back in that process as like cleanliness of the milker. So either clean hands or clean gloves, um, not putting the same pair of gloves on every day when you go into the milking parlor. And even, you know, if you if you do choose to wear gloves when they get dirty, even during the same milking, making sure that those are thrown out and a new pair is put on, um, you just can't overstate the importance of cleanliness for everybody involved in the process.
Joan:And and to add on to that, um, both the um the teat dip container itself. Um, in small herds, the spray can is popular of uh clorohexidine-based product, and one that may not have the entire spectrum that you're looking for in terms of pseudomonas and so on, but those um the nozzle, if left sitting in the barn, often become a really heavy source of contamination. And um, and I have seen on multiple occasions where we believe that was a likely source of a problem. And um, and then again, that just um the the that the teat dip or a teat sealant or whatever product you're using, that you don't want that to become incubation broth for your those that those um many of those can be neutralized with organic material. And also that the it's not just the product, but the contact time with the product, as Rosie mentions. Contact time is really essential.
Michelle:Yeah, that's a good point. And even just making sure that those dip cups get emptied and cleaned daily is um I think most uh that might be something that gets overlooked the most as far as cleanliness goes. We we really shouldn't be leaving those full in between milkings and letting them sit in the parlor. Um really need to spend a little extra to refill the cup after every or before every milking and making sure that we're cleaning it daily as well.
Joan:And stuff a paper towel in that opening.
Michelle:Oh, that's a good pro tip. So I think this is a good part, a good point to start talking a little bit more about the project that Dr. Bush and I are collaborating on with uh evaluating um tissue and milk residues for these two intramamory antimicrobial products. Um and that was the cephopyrin um and the cloxicillin dry tubes, not the lactating tubes. Um of course, Dr. Bush and I are uh kind of right in the middle of the final phase of the project where we're um evaluating the efficacy of these treatments on a targeted type of program. So we're not blanket treating, we're we're just targeting animals that are positive for coagulase-negative staphylococcus, so not staph aureus species. Um, and these are really in our experience the bacteria that are gonna be most likely to be eliminated by these antibiotics and can cause some subclinical mastitis issues that are gonna affect our milk quality long term into the next lactation. But um we're also looking at antimicrobial resistance development with these types of treatments and um basically long-term use of dry-off antimicrobial can affect antimicrobial resistance development. So, Dr. Bush, what do you think that this um research project is going to mean for the dairy goat community?
Rosie:Yeah, I think well, one it's with herds that are using a dry period. Um, so that'll be something that you know, if if herds aren't using a 45 to 60 day dry period, the findings from this project may not necessarily apply. So, but as I think that might be the first take-home is that we're looking at with at this with herds that have a dry period of 45 to 60 days. Um, so that may kind of already show a benefit to production and milk quality there. Um and then I think it'll be really helpful to provide some GOAT-specific evidence-based information on if there is a benefit to either current curable infections or preventing new infections within the dry period. Um I think it's really exciting because there is a cost to implementing this kind of strategy. I think it's really exciting to have data that we can, at least as a starting point. And even with the antibiotic resistance data, we're just looking at those two time points of bacteria. Um, so you know, even if we do see a change in antibiotic resistance, we're not looking at how persistent that might be in that bacterial population. But if there is a change, then this is a starting point to see, okay, now next step would be how long does this antibiotic resistance last within this other bacterial population? Um, and then you know, I usually I feel like most research just leads to more questions, and we already have so many questions, but it's it's really exciting to take this first step and then see where we can go from here.
Michelle:Absolutely. I'm just so excited to have some goat-specific data because we've talked a lot today about anecdotal information and stuff we we've heard from other veterinarians or dairy goat producers, but to really have um some documented data from different farms in different states that have different management styles, I think is going to be so insightful. And like you said, it's a great starting point for just learning more about how goats um are different from cows and what strategies we can utilize to um keep their otters healthy during the dry period. Do you have anything to add, Dr. Rao?
Joan:Well, I actually I had questions, of course. And uh so it's really exciting work, and so I'm really pleased that you all are taking this on and that it's regionally uh across several regions. Um my question was what the common, if you were able to tell us what the common organisms are that you're seeing most frequently.
Michelle:Um well in the dairy that we're working on in Wisconsin, far and away, we're seeing the coag negative staphs. Um, I think I could count on two hands the number of other organisms. I think the second most common would be staph aureus, but um, I've only had a handful of those. And then um just a couple of other, you know, random things here and there. Um pretty minimal contamination too. We're we're getting pretty clear cultures on every animal that we are sampling, unlike bovine studies I've done where there's a lot of contamination. I think that's because the fecal matter is a different consistency, but um we've we've been able to get cultures on um, I think we finished up with about uh 700 animals that were actually cultured. Um, and then out of those, um, we've only selected for the ones that were um positive for the quag negative staffs, and we had about a 40% prevalence of those out of all the animals that were cultured.
Rosie:So and we're just getting started in California. And you know, as we you talked about earlier on, I think it's probably good to bring up again, it's there's a lot of animal identification and record keeping and management changes that need to happen to facilitate this type of management change. And so we're trying to make sure that we when we start, we really have those understood and you know working well so that we can do this because we don't have necessarily a really reliable withdrawal period for these in GOATs. So we're testing before going back into the bulk tank with a charm test. Um yeah, so there's there's you know, potentially there's a cost, a a pretty important cost to consider associated with these types of strategies. Um but if there is a benefit, it's I think it's exciting that there it shows another value for keeping animal identification, keeping those types of records, doing DHI testing, so yet another value in addition to the other types of management strategies that you guys talked about in your previous episode.
Michelle:And I believe um, well, Dr. Bush, you sparked something um in my memory. Dr. Rao, I'm sure you can comment on this, but there is a period after freshening, I think it's two or four milkings, when um those aren't supposed to, or animals aren't supposed to be milked into the bulk tank anyway. Um, and so the cost associated with the you know dumped milk from um potential in a microbial residue may actually kind of be negligible because those animals shouldn't be going in the bulk tank anyway. Um but we are working on um getting that data on the milk residue um compiled so that we can send that over to Farad, the food animal residue avoidance database, so that they can determine the appropriate withdrawals, um withdrawal recommendations, and then those can be disseminated out to veterinarians and producers.
Rosie:Yeah, and just because it's not labeled for goats, they tend to do a pretty extended withdrawal. Um and so hopefully with this kind of data we can approach getting that drug labeled for goats so that the you know there would be a tolerance limit that would be similar to cattle. That would be great.
Joan:Yeah, just for clarification, so I think that this research will be wonderful because you will establish some um residue data. And then that data as part of not um not necessarily a clearance study, but rather because it will be some clinical data relative to the persistence of residues, then that will be used along with other other literature reviews in formulating best recommendations for uh veterinarians then who submit requests to the food animal residue avoidance database to have a best practice for hoping to achieve a zero um uh, as Rosie mentioned, because there's a zero tolerance, then then the veterinarians then can uh will assign to the herd then um a withdrawal time. So unfortunately it'll take additional studies to have a labeled withdrawal time, but then but that database then will be helpful in in um for for Fared to help to help um advise veterinarians on appropriate withdrawals. Just wanted a really general comment, kind of circling back to the big picture and overall information. And that was the uh Dairy Goat Production Handbook that's distributed by Langston University. The first two chapters are from uh Paul Plummer, a chapter on biosecurity, and Chris Dummler, a chapter on herd health, that are a really quick reference that um give producers, and hopefully you all have this anyway, because it's a great encyclopedia of topics of dairy goat information, and that um that those are a really good quick reference for an overview of some of the things that we've talked about today.
Michelle:Absolutely. And I'm always on the hunt for good resources to refer clients to. I think this has been a really great discussion on um setting doughs up for success and managing other health during the dry period. So I want to thank you both so much for making the time to pop on and chat with us today. And um, Dr. Bush and I are excited to be wrapping up this extensive research project that we've been working on, and we'll be getting those results out soon, hopefully. Um Dr. Rao, as always, we appreciate your expertise and congratulations again on your retirement and emeritus status. Thank you guys so much for joining us today.
