 This is Dr. Gerald Stucka and the Extension Veterinarian and Livestock Stewardship Specialist here at North Dakota State University. I want to visit a little bit about some CAF health issues that are somewhat unique to 2022. I just want to set this up a little bit by talking about some things that were unique to 2022. We had tremendous early spring summer forage growth and then the summer term dry and so that had an impact on forage quality, not necessarily so much on trace minerals, perhaps on vitamin A but what we see the impact was we saw perhaps lower weaning weights, even decreased yearling cattle canes, you know some of that do obviously to lower milk production by the dam and less quality forage for the CAF itself. So some of those things are a little bit unique to 2022 that were not with us in 2021 where we had pretty much dry season all summer. Just we're going to talk a little bit about bovine respiratory disease and what to expect. I mean I expect that weaning calves on the ranch of your own place without bringing in new cattle that you'll certainly have less than one percent mortality and certainly less than five percent morbidity. That's the goal, zero is great if you can achieve it. And then talk a little bit about what's preventable, we'll talk a little bit about multiple groups and coal mingling and related to multiple pastures, the dietary change and so on and so forth. So there's many things that go into weaning calves not related necessarily to yearling cattle but to weaning calves and what the stressors are and how they contribute to having a calf that's more susceptible to infectious disease. Then just a little bit about the unexpected, sometimes we'll get respiratory outbreaks or even other outbreaks maybe related to pink eye, foot rot or polio even that are later in the feeding period in backgrounding operations. So those things that occur 45 to 60 days post weaning may be a BRD outbreak but may be one of the others that we just mentioned. And then we'll finally talk a little bit about vaccination. So what's important for me when I deal with these kinds of issues is to have a real history. When I go into a herd and we'll just use this example, a herd that's experiencing post weaning respiratory disease, it's important for me to be able to visit with the people that are involved. Whether it's the veterinarian, whether it's the owner, the manager, the herd person, hired labor, just need some kind of specific details related to the history of when it started and then I like to be specific about the dates. As I said earlier, when it started, how many did you treat, when did co-mingling occur, what did you vaccinate with or not vaccinate with? How many treatments there were and how many you had to retreat and perhaps even how many died? So the number of animals is always important. It's what we use as a denominator. So how many animals did you treat? A lot of how many animals that we would consider at risk or how many animals were weaned and if there are several pens, how many animals in each pen and how many were treated in each pen by the number of animals in that group. So I think it's important for us to visit a little bit about healthy animals and sick animals. I think that many of us can pick out an animal that's really ill, but in order to be very proficient at this and an expert at this, you need to know what a well animal looks like and I think that's important as a starting point. So when I talk about wellness, we use some of these objective measurements like appetite. I mean, are they coming up to eat or not? Animals tend to be curious, even animals that have a temperament that that maybe puts them at the at the farthest limits of the pen or a quarter of a mile away, they're still should be somewhat curious. They should turn their head and see who's looking at them. These animals in the upper right corner here have come right up to the feeding bunk and they want to know who you are. And so it's an animal that is curious, but there are other attributes as well like being bright-eyed. I would attribute those animals to have being bright-eyed. They want to know you and want to see what's going on versus an animal that's we would say dull-eyed or exhibiting signs of non-interest that that eye just looks different to the trained observer. They should have a good hair coat, they should groom themselves and others. And as I said earlier, they should be curious. Some of these other images in this picture in this slide demonstrate cattle that have been shipped a long distance, especially that one in the lower left there, a calf that came from the state of Alabama came to the state of Kansas and the weather was not great for that animal. It surely needed some tender love and care, even though that animal itself was not that ill. It just was in an environment that it was not adapted to yet anyway, until it got some good feed into them. The one on the on the right on that one is an animal that had been experienced a long haul, a little tired. You can't really tell so much for that image, but those are all things you have in your mind as you're looking at animals. Do they look well or don't they? I got a couple of pictures here and this relates to some terms that we use. We use the term sign to indicate some type of objective measurement that things are not well, things like rectal temperatures. We'll take a rectal temperature in an animal. We want to see what it is. If it's too high, then we'll come to the conclusion that there's something going on in that animal. There's some inflammatory response and it may or may not need treatment. In most cases, we probably are going to treat an animal if we have what we believe is an elevated rectal temperature. The other one is more related to symptoms, a depressed animal. It's more of a subjective term, I guess, than an objective term like rectal temperature. But the ADR there just stands for an animal that ain't doing right. So we consider that to be an indication that the animal's not feeling well. And you can see in these images here, there's a couple of animals that pen conditions aren't great either and that can make animals not real happy. But these animals are experiencing more than just poor pen conditions. They're not feeling well. And that should be obvious. And the question becomes, should I have seen that animal the day before or two days before instead of noticing it just now on this date? Interestingly enough, the animal in the lower right there has a, what I would call a treatment tag. And sometimes those treatment tags will be put in in some yards. As an indication that they've been treated, they may have a date on it, they may have a notch on it to indicate whether they've been treated once or twice. So sometimes that's helpful in pens that contain a large number of animals so that you're not confused by looking at an animal that was simply treated the day previously and then put back in the home pen. So what do we consider to be normal in terms of rectal temperatures? Really normal is 101 and a half plus or minus a degree. But they can certainly be up to 103 and a half and still be normal, depending on what the environmental temperature is like. So I don't really have a hard and fast rule that unless an animal's 104 and higher that I'm gonna treat that animal, there's gotta be some other symptoms involved as well. And sometimes we can be confused by parents, animals with longer ears that we don't see much up here in the Northern Plains. But certainly in the Southern Plains we do, we call them eared cattle. This image here is certainly one that has, that animal has some boss indicus or Brahmin pedigree. And the ears are a little bit longer and sometimes those ears take a little more energy just to keep upright. And so sometimes you can be confused by a long-eared animal that the ears are down and you think it's depressed. And so it takes some trained observation in addition to just running a fever to determine whether an animal needs closer inspection. Do I need to run that animal into the squeeze shoot and actually have a look at it and determine whether I need to treat that animal with perhaps with an antibiotic. So there's many reasons. And we talked about coming to the bunk as a sign of wellness and there may be other reasons why animals don't come to the bunk. One of them may be simply water. Do they have access to water? Is there enough animals can drink at the same time so that they meet their water requirements? Or sometimes in the Northern Plains especially, be very concerned with intake and animals not coming to the bunk if somehow something's wrong with water, whether it's frozen or whether there's actually electrical current in the water. Those animals will not drink and as a result they will not eat either. So you'll have animals that are kind of shrunk up in the flank and evidence they're not eating. They may simply be shy. They're not very competitive. They don't come to the bunk. They're not used to their other penmates or herdmates and they're gonna be the last ones to come to the bunk and sometimes there's not enough space for them all either. And so you have to account for that. And lastly, they may have disease. They may not feel well enough to come to the bunk and eat some feed. This slide is kind of an illustration of what happens in respiratory disease and why we kind of need to know some of the anatomy that you can't see necessarily when you're certainly looking at a live animal and you can't really see these things even when you're doing an acropsia on an animal. But this is the respiratory system and how the airways work. We start up at the top of this illustration here with trachea and then it branches off into smaller bronchi and bronchioles and you get down to the really small air spaces that we call the alveolar sac or alveolus. And that's where air exchange occurs. We're a calbreed off and a CO2 and that's where oxygen comes in through those alveolar spaces, alveolus, and the animal gets oxygen. So when we have respiratory lung damage, then those air spaces don't work the way they should be or should and animals can have certainly respiratory distress. They're not getting enough oxygen into their system. This is a very real image of what it looks like when you have destruction of respiratory tissue. This is a picture of calf in which we retracted the ribs. The head would be on the right end of this image. You can see where the liver and the gallbladder is and the rest of the viscera back there but this is a picture of lung tissue. There is not a great deal of good lung tissue here. This lung tissue up here looks a little bit better, obviously. Then the tissue down here, this looks more like the color of liver. And in spaces like this, you're not gonna really have any space in that lung tissue where transfer of CO2 and oxygen can take place. So I've got an animal here that at least on this side of the lung, there's maybe 50% of lung tissue that actually works. This is another slide and again, the head would be on the right. There's liver again. It's a little bit different picture. This is an image I got from the diagnostic lab at North Dakota State. You don't really see any, any what I would call nice lung tissue here at all. It's reddened. There's certainly something going on here. And this one has actually had a couple of pathogens that were involved, BVD, bovine virus, diarrhea virus and mannaimia melodica. And what's interesting down here is it looks a little different down here. We've got a layer of what we call fibrin, which is an acute phase protein. And acute phase proteins comes into play in an animal's attempt to heal itself, to wall off the infection. And in this case, as you'll notice, this animal didn't survive. And so we've got a lung tissue here that's basically non-functioning. This is a picture of the upper airway. This is the trachea, right here, the windpipe. And this is a calf that had what we call calf tetheria or necrotic laryngitis. In some cases, it can be caused by the same organism that causes foot rot. In other cases, it could be caused by a histophalosomni, for example, and even other organisms. But the difference with a calf, with calf tetheria, is how they sound, because they're always going to make a lot of noise. So this is right in the vocal cords of this calf, this big lesion right here. And that causes the sound or the air that travels past this lesion to become very noisy. So if you've got a calf, its head may or may not be distended, but he's really making a lot of noise. And he may be breathing fast. Usually that noise is coming from the vocal cords. It's not a sound that comes down deep into the lung tissue itself. So this one's a little bit different and don't be fooled by it. And in many cases, these lesions, not one like this, obviously, but can be treated with an antibiotic very successfully if you deal with them early enough. Here's one that's a little bit different. Let me just use my marker here again. We've got a calf, again, that the head is on the right over here. Here's lung tissue, here's gallbladder, these are intestines back here. So this lung tissue up here looks fairly normal. There's still spots in here that are not, but we've got some liver colored looking things down here. You know, this is probably less than 50% of lung tissue that's viable. That's dark, it's red. And what you see uniquely down here is what looks like little white pimples almost, if you will. And that would be pretty typical of a calf that has mycoplasma pneumonia. Those calves tend to be very difficult to treat. They don't always exhibit real strong signs of being ill. The recal temperatures may not always be that high. It's more of a chronic type of infection, I should say. And what these are, these little white lesions here in the lung tissue, they're actually small little abscesses on the lungs. And obviously this calf can't get enough air, oxygen transfer and CO2 transfer as well. So it's succumbed to that mycoplasmal organism that was in its lungs. Sometimes as a sequelae to mycoplasma pneumonia, we actually get mycoplasma arthritis. This is the knee of a calf, the hind limb of a calf that has arthritis. And as I opened up this calf, this will change colors here. This is actually pus. In the joint of a calf, it's a dried pus. We sometimes use this term insipidated pus, but nevertheless it's assigned a tremendous inflammation from mycoplasma in the joint of the calf. And those are extremely difficult to treat as you might expect. So this calf, not only at pneumonia, but it metastasized into the lungs as well. Difficult treatment. Just want to follow up that with a little bit of a comment about mycoplasma. This was a study that was done a number of years ago, but at that time Pfizer animal health and this study was never written up, but it was important and I gleaned some information from it as it relates to mycoplasma. So what they did in this study, they took in high-risk calves and they had like 10 groups, 60 calves in each group, and I just picked one here primarily. But they would take deep nasal swabs of these calves every 10 days or so. Day zero, they took a swab, day 10, day 21, and then went out to day 28, and then again at day 60, just to look at what pathogens they could isolate, at least bacterial pathogens from the deep nasal swabs. And so I want to focus on mycoplasma bovis here and its illustration of how rapidly that organism can spread within a population. So on day zero, I had, I don't know, somewhere around maybe 5% or less, maybe even just a couple of animals that were positive, but by day 10, I had 75% of those animals that were no positive on culture from deep nasal swabs. The difference between these groups is that in this study, it was an antibiotic study where they gave antibiotic, and so you're starting with kind of the same number of positives, really low positive. By day 10, we had a little over 50%, but then by day 21, we hit 75%. The only takeaway here is that while the antibiotic didn't stop the spread, it somewhat slowed it down a little bit, so at least you might gain some element of time in trying to manage these cattle a little bit better, at least as it relates to Ambovis. And we kind of see some of the other organisms here, the deep, the dark green is a manhami hemolytica, the gray is pastoral amyltosida, and this kind of dark purple or dark blue line is H. somni, what I find interesting on H. somni is later on after arrival is when H. somni seems to start coming into play. Couple comments on mycoplasma vaccine, I'm not a big proponent of it. I haven't seen a whole lot of science that tells me that it works the way it's supposed to work. So this first bullet points are just on a killed vaccine from mycoplasma boas and didn't really see evidence of efficacy on either on ear infections or respiratory disease. There is a new mycoplasma vaccine that's being marketed by Zoetis. It's a modified live vaccine, which is what I felt for some time that we probably needed in order to have some effectiveness against this organism. I don't really have any peer-reviewed literature to talk about in regards to this vaccine. So we'll need to kind of discover perhaps for ourselves what the efficacy really is on this particular vaccine, you know, whether giving it on arrival and high-risk animals is really gonna be effective or not. It's currently labeled to be used in cattle a one week of age or older against respiratory disease and duration of immunity has not been established. I'm gonna use this example of some of the times, the things that come into play that have very little to do with vaccination and more to do with management than anything else. This was an email that was sent to me a number of years ago from someone in Georgia who wanted me to comment on a vaccine protocol that they used in bull test station. It says concerning a vaccination protocol sent to the bull test years ago by someone at the vet school in Athens, Georgia. Incoming bulls must be vaccinated two to three weeks prior to our arrival with IBR, PI3, BRSV, BVD, one and two, mannaimia hemolytica, pastoral maltocita. Now histophalosomnus instead of humophilus, it's called histophalosomni and clostrial seminoid. So I mean, the idea here is correct to try and immunize animals against certain pathogens at least a fair amount of time before the stress of movement and other stressors come into play. And then at processing, which means they've arrived at the bull test station, boosters will be given using whatever vaccine some companies will donate. A little more history with this one. Typically processing is in around July 5, which would be different than our bull test stations up here, but, and the bulls are sold around December 7th, within seven to 10 days after arrival, they're numus cases of BRD, which are treated and may be retreated and the process really runs to late November. And the question was if the protocol pre-arrival and at processing was an intranasal vaccine, that's the acronym IN, like TSV2 where we could use nasal gin or N4-3, and an intramuscular or subcutaneous manheimia hemolytica, pastoral maltocita vaccine, plus clostridial, omitting the humophilus or histophalus, would there be less BRD? I would appreciate your advice. The answer is no. I know equivocally, no. It's not gonna make any difference what you vaccinate these cattle with, because what you're dealing with here is the impact of co-mingling. When you bring a bunch of bulls in and I don't know exactly how they pen these bulls, but usually they're penned by breed when they come in. And they almost never have them penned by owner. And I don't know whether they were committed to having three bulls or five bulls or less or more or more, sometimes one bull, they're gonna have co-mingling occur. And that's really what's going on here. So somehow management needs to change as to how they pen these bulls and how they're handled within the early arrival period because they'll continue to have respiratory disease unless they deal with the co-mingling effect. Now, I'm leaving out any comment about nutrition. Usually in bull test stations, they strive for high average daily gains and that can play a role in putting a little extra stress in these animals and resulting in perhaps respiratory disease as well. So in summary, I just wanna talk about a few issues here and I've used the term prevent the preventable. And I spend a little bit of time talking about the factors that the stress factors that result in calves becoming ill after weaning. And one of those was co-mingling and that's why some of my recommendations reflect that management strategy to prevent co-mingling at the same time the calves are weaning. So feed all the groups of cows and calves together to prior to weaning, if possible. When you do that, it allows the calf to getting used to eating a ration. It may be off the ground. It may be in bunks, depending on herd size. And you don't necessarily have to feed the exact same ration, but some of the components will be the same as what you're going to use once the calf is separated from the mother. So when you do that and you do that for two weeks or three weeks, they're about, it removes because the pecking order, the social life, if you will, becomes reorganized. And that co-mingling stress becomes reduced. The only time when I've seen it not work is when you've got groups of cows and calves together, but the space is so large. In other words, a section of ground, for example, and you're feeding in two different spots in that section of ground, then co-mingling doesn't occur even when they're with our mothers. So make sure that all these cows and calves are being together and you're feeding them them in one place. In addition to that, just observe these calves for signs of wellness. Are they acting normal? Are they curious? Do they groom each other? Are they bright-eyed? And of course, when you're walking the pens and it's important to walk the pens. It's important to have kind of the same person or maybe two people that trade off but walk these pens so the calf gets used to who you are and you're used to those calves and how they behave. But you need to observe for wellness, but also observe the manure. Is it too runny? Is it bloody? A runny might indicate that the calves are taking in too much energy. They may be acidotic. If it's bloody, the calves may be exhibiting signs of coxidiosis. We will use ionophores in many cases to prevent coxidiosis. We also use them because they help cal make use of feed in a more efficient manner. But there are specific products that are coxidiostats as well like Decox or Decoquinate and Amprolium. Sometimes we'll use them in our weaning rations as well. When you have calves that are breaking with coxidiosis and you're feeding these products and the break occurs before approximately day 21, that means that the infection occurred before, before you were able to put in some of these coxidiostats. Decox can work in different ways, but especially in the ionophores. Because the life cycle of coxidiosis is about 21 days, when they are after 21 days, you know that some of those calves are not getting the right amount. It may be related to intake. It may be related to the inclusion rate that you have in that ration. In terms of vaccinations, the virus vaccines we use today are very good. They slow the spread of transmission. They diminish the signs of illness from the viruses themselves. So they work and they're efficacious. Some of the bacterial pathogens I'm a little more skeptical of. In Menheimia hemolytica, there's some evidence that it limits lung damage. Pastoral autism, histoplasomni, in my mind there's limited scientific evidence for their efficacy. I don't try and talk people out of it necessarily. I don't necessarily recommend their use, but if they use them, and I'm not saying we don't need vaccines for those pathogens, it's just that we may need a different technology to evaluate the efficacy of some of those vaccines in the future. Mycoplasma bovis, the same, I have there's limited scientific evidence for efficacy. There is a new one on the market, productivity, and I really don't know a great deal about that particular vaccine to recommend it at this stage. So thank you for listening. I hope this was helpful. And remember that the specialists are here to help in any way we can so don't hesitate to get in touch with us. Thank you so much.