Host Lynsey McAnally (00:19):

Angus at Work, a podcast for the profit-minded cattleman. Brought to you by the Angus Beef Bulletin, we have news and information on health, nutrition, marketing, genetics and management. So let’s get to work, shall we?

While many farmers and ranchers had hoped New World screwworm would stay well south of the U.S.-Mexico border, we’re now all well aware that wasn’t in the cards for American cattlemen. With a few days to let that news sink in behind us, our attention turns to one question: Now what?

Right off the bat, we want to share something USDA, APHIS and the Texas Animal Health Commission have already stated:

A) No one needs to panic. There's a plan in place and we know how to eradicate this pest.

B) New World screwworm is an animal health issue, not a food safety issue. Meat remains safe to eat and treated and inspected cattle can continue to move from affected areas, tracking potential spread within the U.S., how to protect our herds and what the near future might look like for cattle movement are top of mind.

To help our listeners navigate this new information, we were joined today, Tuesday, June 9, by Jennifer Koziol, associate professor of food, animal medicine and surgery at Texas Tech University, to discuss recent announcements and what cattlemen need to keep in mind for the near future related to New World screwworm.

Before we dive in, we want to say a big thank you to GeneMax^® for their sponsorship of this episode.

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Host Lynsey McAnally (02:31):

Welcome to Angus at Work. I’m your host, Lynsey McAnally, and today we’re joined by a special guest, Dr. Jennifer Koziol. Dr. Koziol, thank you for being with us today. Do you mind giving us a little background on yourself and your role at Texas Tech University?

Jennifer Koziol (02:46):

Yeah, so I’m Dr. Jennifer Koziol. I am currently an associate professor of food animal medicine surgery at Texas Tech School of Veterinary Medicine. So that’s a lot of words to tell you that I’m a cow vet that practices in Amarillo, Texas. Originally from a cow-calf and stocker family in eastern Oklahoma, and so excited to join you today.

Host Lynsey McAnally (03:09):

I would bet money that many of our listeners are familiar with New World screwworm, but just in case, can you give us the basic need to know details?

Jennifer Koziol (03:17):

Yeah, so New World screwworm ... We had New World screwworm in the U.S. in '50s, '60s and kind of eradicated it out of the U.S. Some people will say in the '60s, there was parts of Texas that were still infected in the '70s. We pushed this fly back. This is a fly — an insect — and we pushed it back all the way to the Darien Gap. So think about Panama. We’ve really maintained that border. And then during COVID we had a little bit of a breakdown of that border and the fly started traversing back north. We’ve watched it march across Mexico. About a year and a half ago, we got very concerned as we watched the northern progression of this fly. Many of our listeners will remember the shutting of the Mexico border and the impacts that that's had on imports of Mexican cattle.

Unfortunately, last week we had our first positive animal in Texas. This is a fly [that] lays its larvae in or around wounds. It will lay its eggs on any warm-blooded animal. So not only [are] our cattle populations at risk, but any warm-blooded animals. We will also be thinking about our wildlife species, too. There have been human cases, as well. Those larvae will eat the living flesh on those infected animals and that's really how the larvae survive and thrive. Once the larvae gets to a point, they'll fall out of the wound to go through a pupae stage and then they will hatch out and become flies. We have long in the U.S. ... We eradicated it using the sterile insect technique (SIT) where we release sterile flies to mate with the females. Once the sterile flies mate with a female, she won’t lay eggs again because they only mate once.

So that’s really how we’ve knocked out that population of flies and driven them back. That’s where we are today. Unfortunately, we’ve had four cases reported in Texas, one in eastern New Mexico, and we’ll see what the days have to bring us going forward.

Host Lynsey McAnally (05:26):

Thank you so much for giving that background. Like I said, I think most of our listeners probably are familiar with New World screwworm, but it’s always nice to have a little bit of a refresher, especially when we dive into some of this deeper content here in just a second. With that covered, I really want to roll into what our producers need to be aware of when it comes to New World screwworm here, particularly in the state of Texas and now that it’s crossed the border. What is the potential cost of preventing screwworm from reestablishing here in the U.S.? Working with ranchers to be vigilant, working with these state and federal agencies that are now here in the state of Texas helping to deal with those cases vs. dealing with it on an annual basis if it were to reestablish.

Jennifer Koziol (06:10):

Yeah, absolutely. So economic impact has been calculated for the state of Texas and it's quite a huge number. So it can be really quite impactful for us. I think what we need to think as cattle producers is how we’re going to manage [these] flies. There’s some really key things that we can keep in mind. So vigilance and surveillance, right? Eyes on cattle is the number one thing that we can do is to recognize a wound so that we can get those wounds taken care of before they become affected. And if a wound does become affected, recognizing that so that we can treat those animals so we have minimal loss from that. So that's number one, right? Surveillance and vigilance. If you have concerns about a wound, contact your veterinarian or your state veterinary office. If you’re in Texas, that’s going to be the Texas Animal Health Commission (TAHC).

If you are in any other state, contact your state veterinarian. There’s going to be numbers posted everywhere. Call your veterinarian, call your extension agent, just call somebody. Let them know, “Hey, I have an animal that I’m concerned about. What do I need to do next?” They will walk you through that. They will gladly walk you through that. So that’s our two biggest ones: surveillance and reporting. Also, paying attention. We know that all of our ranches, wildlife is a big part of those and that we see a lot of wildlife go through. So paying attention to those wildlife populations is going to be really important. If we see an animal that we think is affected, has a wound, we're going to call our state Parks and Wildlife. So in the state of Texas, that's Texas Parks and Wildlife. They're a key partner in our fight against New World screwworm here in Texas.

And so we're going to call them other states like Oklahoma, New Mexico, whatever your Department of Wildlife is, call them, let them know where you saw that animal and they will take it from there because we're going to have to really pay attention to those wildlife as they traverse through and can potentially spread that New World screwworm. Those are some of the big things on the front part. Other things that we need to start thinking about is how we manage our cattle herds. So as an infected zone gets closer to your operation, how do I need to change my management practices? Do I need to shift my breeding season so that we have during months where there is no New World screwworm because it is too cold for them to survive and thrive? Do I need to shift it if I'm in the deep south?

Do I need to shift it to a time when there is lower New World screwworm numbers because calving management is going to be really key. These flies love the umbilicus of a newborn calf, a newborn lamb, a newborn anything. And so we're really going to have to think about how we're going to manage our calving seasons. Breeding season leads up to calving season, which then thinks about branding season. And then we think about how the rest of our management plays out. How am I going to dehorn, castrate, brand, implant, all of those things, thinking about how I'm going to do that and working with your veterinarian to come up with a treatment plan, prevention plan, and just those big management decisions you make on a daily basis. So I think those are really some of the things that we need to start thinking about as cattle producers.

Host Lynsey McAnally (09:49):

Which I think rolls really well into something that we put a lot of emphasis on here at the Angus Beef Bulletin:  having a relationship with your veterinarian aspect. And so having a strong relationship with your local veterinarian is something that everyone — every cattle producer — should put some emphasis on. Can you highlight for our audience why that VCPR is beneficial at times like this?

Jennifer Koziol (10:14):

Yeah, absolutely. Having that VCPR is going to be really important for lots of factors. Some of the newer drugs that are coming onto the market are going to require a prescription from your veterinarian, which we need a VCPR to script that out. If you would be in need of that product, you do need to have that VCPR with your veterinarian. Your veterinarian's going to be a great source of thinking about how you can judiciously use the products that we have against New World screwworm. If we think about products that we're going to use against New World screwworm — like Dectomax^® and Ivomec^® — we also use those for our internal parasite control. So how are we going to use those in a manner that they still work as our internal parasite control, but also we are prepared to use them in a situation where we need to fight off New World screwworm.

How do we balance those two? So those are two great examples of why a veterinarian becomes really important. And then also thinking about permitting. So we are going to have to have a lot of inspection of animals to move. And so you want to have that good relationship with your veterinarian so they know you're herd, they know what you've done. And so if you were to be in a situation where you need to move cattle and are in a restricted area of movement, you have that good relationship so you can have continuity of commerce as much as we possibly can. I think that's really important. If you listen to what USDA and Texas Animal Health Commission have really talked about, really continuity of commerce is really what we are hoping to achieve for the betterment of the beef industry. Minimizing those economic impacts as much as we can so that the sector of agriculture continue to thrive.

Host Lynsey McAnally (12:08):

There are so many places online and so many media outlets that are reporting where producers can report a potential case. We will go ahead and pin that at the top of our Facebook page for any producers that need to access that information. I'll include that in the show notes as well. But as far as people reporting those cases ... If they have a suspected case, I am assuming — perhaps incorrectly — that we should not be moving those cattle to a veterinarian?

Jennifer Koziol (12:36):

Yeah. So, ideally, we would not move those cattle depending on where you're located and how far away you are from your vet, you might see your vet might make a house call. Somebody that works for the state veterinarian might make a house call or something of that nature. Most states are rolling out test kits. So your extension agent might actually bring you a test kit and we are going to pull larvae out of those open wounds and we're going to put them in alcohol and then depending on your state, it will get shipped. So some states are sending to their state diagnostic lab. Here in Texas, we're sending them straight to the National Veterinary Diagnostic Lab for identification at this time point. That may change in the state of Texas, but that's currently what we're doing. Every state is rolling out their test kits.

And so one of those may show up at your operation. What you're going to do ... Wearing gloves, you're going to use tweezers, pick those larvae out, put them in a container containing alcohol and then they'll be shipped off for identification from there. And so some things that we really want to think about is when we're pulling larvae out of those wounds, we want to be very careful not to drop any on the ground because those larvae can then turn into other flies. So if we are cleaning out the wound that we suspect we want to A) make sure that we get all the of them that we physically can and that we make sure that we don't drop any on the ground, but that's how that's going to work. And so yeah, ideally those animals would stay on the premises and that we wouldn't move those just so we don't have the chance of dropping any of those larvae along the way and increase the distance that they have traveled.

Host Lynsey McAnally (14:27):

We are seeing terms like infested zone and surveillance zone now being used. What differentiates those two terms and what do producers need to know about movement restrictions that are currently in place?

Jennifer Koziol (14:41):

Right. So an infested zone is going to be the zone immediately surrounding the premises where there was a infected case. Infested case is the term that they're using. So an infested zone is going to be a radius surround that. And so within that zone, you're going to need a permit to move animals. So animals are not going to be able to move unless they are treated and then they're not going to be able to move for about 72 hours after they have been treated. And so you are going to need a permit. So keep going back to the state of Texas because that's where we're actively fighting this. We're going to treat those cattle. They're going to have a 72 hour hold and then if they need to go anywhere, they will have to have a permit issued by Texas Animal Health Commission to go out of that infested zone.

Now it's really important to think about where you're going. Some states have already said that if you come from an infested zone or drive through an infested zone that you will be not allowed to entry. So it's important to look at those state regulations and make sure that you're in the know. Your animal health officials will be really helpful in trying to keep up on those, but always and your veterinarian will also be able to call that state of entry and make sure that you're good to go. So that's the infested zone. So really doesn't stop movement, but we're going to really hold until we've treated everything once we've treated, then we can go with a permit. The surveillance zone is just a zone around that infested zone where we are doing increased surveillance. So that's not an infested zone. There hasn't been anything found yet in that surveillance zone, but realizing that it is a close enough distance to that infested case that there is the potential.

So we're highly monitoring that area. And so within the surveillance zone we are just increasing usually we're dropping ... In Texas, that is where we're doing our ground release of sterile flies. Within our infested zone, we are doing aerial drops so they get them exactly where they need them and we're really trying to just minimize the spread of that New World screwworm.

Host Lynsey McAnally (17:12):

I just wanted to ask, you're right there on the cusp of cattle feeding. We have a lot of cattle feeding in that area. I don't know that I've heard anyone up to this point talk about what would happen if New World screwworm got into this part of Texas and cattle feeding areas. How might that management differ in a feedyard setting vs. a cow-calf or stocker operation?

Jennifer Koziol (17:38):

Yeah. So if we were to get New World screwworm this far north, certainly from a management standpoint in feedlots, we would just be extremely cautious about ... This goes back to our management practices. So if we get a set of steers in and we need to implant them, etc., we are probably going to use one of our products that's labeled for prevention of New World screwworm. We know we're making an open wound. We know that we are in an infested zone and so we would use those management practices and our pen riders would be really looking for any open wounds. We would be very, very quick on the spot for any footrot, anything like that. Just anything that would have an open wound where a fly could lay their eggs. We are going to be very quick about treating that animal using something on that wound that's going to deter the fly from laying eggs there and be very vigilant about getting to those animals as quick as possible and thinking about how we can ... We don't want to get those cattle out of their pens as much as possible.

We want them to be in their pens eating. And so really thinking about how we can tighten our management plans just so we're not creating wounds just from normal practices like ear tagging, implanting, etc. So those would really be ... A feedblot is probably one of the easier ones to manage. We can really watch for wounds. It's a very controlled environment. Cattle are easy to process through and really think about how we can use our drugs for prevention and treatment. So that's really what we're thinking about from a management standpoint and the feedlot. Honestly, in my opinion, some may differ from that, but I think a feedlot is a little easier to manage than our cow-calf producers that are going to have to be out there really paying special attention to each of those calves that hits the ground. And so I think from a labor standpoint, our cow-calf producers have a little bit more on their plate than we would in the feedlot.

Host Lynsey McAnally (19:53):

One of the things that I know has been a discussion point has been how are folks going to be able to get cattle moved to harvest if they're in a feedlot setting. Even if we have some folks who maybe are more farm-to-table or selling directly off their operation, has there been any discussion on what might happen if we do have more incidences of New World screwworm and how folks might be able to get those finished cattle to harvest?

Jennifer Koziol (20:19):

Yeah, absolutely. So I think with the model that we're working with right now that we certainly will be able to permit those animals out and I think there will be the recognition that we can't have a withdrawal time. So there'll be very close inspection of those animals within an infested zone to try to get them out to a market where they are. And so I think, hopefully, there will be some gives and takes within that if there were to become a finishing operation within an infested zone. So thinking about that, or perhaps we might have to use one of our low ... depending on how regulations go, we can't control the government. We can just play within the rules that they give us. We may have to move those animals, permit those animals out of the infested zone closer to the slaughter facility. We'll choose a drug that has the shortest withdrawal time and let those cattle hold there.

So I think those are probably the two situations that we're looking at and we'll see how the government reacts as we go through this. But I certainly think that with their eye on maintaining commerce, that there will be some reasonable concessions made going forward.

Host Lynsey McAnally (21:36):

We've seen these cases, I would say the overwhelming majority at this point in the U.S. have been in newborn calves less than a month old. We had some reports yesterday of a case in a goat. I did not see that pop up on the map yet. And then we also had the case in New Mexico - that was diagnosed in the state of Texas - in a dog. And so I guess my questions right now for you really revolve around what do we need to be looking for if we're off the front lines? So what do we need to be looking for? What does the public need to know? And then as far as travel restrictions, are folks that are traveling into Mexico ... When they come back, is there any sort of safeguard in place to ensure that it's not moving back either on a person or a companion animal?

Jennifer Koziol (22:24):

As far as what you need to be looking for, certainly keeping an eye on the news if you're not in South Texas. If you're not near where one of the confirmed cases are, I think it's really good to just keep your eyes on the news and realize that it's in the U.S.. It is. By the cases that have [been reported], it's widespread across the bottom third of Texas. And so I think that ... I can't iterate enough, right? Vigilance. Eyes on animals. And if you see anything, if you have any concerns, call your veterinarian, call your state veterinary office, call an extension agent. Those are your go-to people that will have the resources that you need to. I think those are ... If you can avoid traveling to those areas or near those areas, I would certainly encourage that. We understand that commerce needs to happen. We are hoping that commerce will still go on like we need it to and we certainly understand that.

But if you can avoid those areas, I would do so. And as far as companion animals moving across from Mexico? That case that was in Lea County that was originally diagnosed in Andrews, Texas, but resides in Lea County, New Mexico. It was originally reported that [dog] recently traveled to Mexico, which raised a lot of concerns. It was confirmed this morning that travel had not been a history of that pet, but I do think it raised the concerns that we do need to have surveillance on those companion animals. How that will be carried out, I have not heard yet, but certainly keeping an eye on that. Humans, certainly, that is also something that we need to think about. Unfortunately, with all the airports that people can travel through from Mexico, Central America, [and] South America, we're really kind of at the mercy of the system with that.

Hopefully we can find some ways to kind of mitigate that and certainly I think all of us are really hoping that some of the beagle detection dogs get rolled out in some of these areas that can really help with mitigation on those standpoints. So those are kind of the things that we're looking at, realizing that there are opportunities for those that happen. They've already happened. You all remember in the news where a human did come into the U.S. that had New World screwworm and it was diagnosed in that human in the East Coast. We are lucky that we didn't have any adverse effects from that, but certainly raises the awareness of how vigilant we need to be and how all the state agencies need to work together, realizing that everybody can be infected with that. So certainly a lot to do. USDA [and the] Texas Animal Health Commission are really doing a good job about working together [with] Texas Parks and Wildlife.

They are all three presenting a very united front and working hard to address the issues and really shore up the lines. But certainly can't reiterate enough about how important it is for everyone to be vigilant and if you see something, say something. Because even if you see a deer driving 80 miles [per hour] down the road and you're like, "That thing has a big nasty wound on its side. That really concerns me." Call somebody. Let them know what you saw and let them take it from there because we don't want those cases to go undiagnosed just because we say, "Oh, well, that's not my problem to worry about." I think it's everybody's problem. That's kind of my big takeaway from this whole deal.

Host Lynsey McAnally (26:27):

Can you go over real quick what restrictions, if any, are in place? Obviously the border was closed quite a while ago to livestock, but as far as other animals moving across the border at this point, are there any restrictions in place for companion animals moving from Mexico into the U.S.?

Jennifer Koziol (26:45):

Yeah. So the U.S. has stopped export to Mexico at this time. We've obviously stopped import of cattle from Mexico, those are big things that we need to think about. I haven't heard that they're going to stop the import of companion animals from Mexico at this point. Horses usually have to go through a quarantine depending on where they're coming from. So we'll see how those play out over the coming days and weeks, but we've stopped export to Mexico. I know Canada has really tightened up their import at this time and so we will see what the next days and weeks will look like for us.

Host Lynsey McAnally (27:34):

So we talk about where New World screwworm is currently, but are you comfortable talking a little bit with us about the seasonal limitations of New World screwworm? So what are we looking at as far as when they might grow in population as far as temperature and then where is the potential range in the U.S.?

Jennifer Koziol (27:55):

Yeah, so it's pretty interesting to look at. So New World screwworm really thrives somewhere in that ... they don't really like temperatures lower than 50 degrees. They're a little bit like Goldilocks. They don't like it's really cold and they don't like it extremely hot. Then they do like a little bit of moisture, but they can survive in pretty arid conditions. So with that being said, New World screwworm, really the populations really decline below 50 degrees. They really ramp up in the summer when it is in the 80s and 90s. They don't love it when it gets over 100, but they can tolerate it to some extent. So currently the maps, there's people that really have projected the pattern of New World screwworm with increases in global temperatures that have it going much further north than what we have historically seen. So I think we can think about it going up ... if we think about in where it was in the '50s, '60s, it went all the way up into Oklahoma, part of Kansas really went east through the Southeast.

Florida is obviously a great environment for New World screwworm. I think the maps, they do have the fly going much further north and having it go much further west than what we had have historically seen. And so I think those are all things that we need to think about. Also, animal movement is much more widespread than it was in previous years. Transportation has changed a lot over the decades and I think that's something that we need to think about. And so that's where just because you live in northern California doesn't mean that you should let down your guard about this. I think that's one of the things [so] that it doesn't become ... It's not an imminent danger, but certainly we should be aware, be ready and have it on our mind. Be thinking about it. I'm not saying that it's going to go there, but it does have the potential to spread far and wide if we get the right temperature conditions.

Really peak is going to happen during the summer and into the fall. We're going to see a dip during late fall winter into early spring and then we're going to see those fly populations increase through the spring and into the summer. So that's really the patterns that we're looking at and why we think about management shifting our management plans so that we can do the most when there is the lowest fly population.

Host Lynsey McAnally (30:37):

Is there anything we've forgotten or anything you think is important to mention?

Jennifer Koziol (30:40):

I think we've covered a lot of ground. I think we're good.

Host Lynsey McAnally (30:43):

So Dr. Koziol, thank you for taking the time to speak with us today. I know our audience is going to really appreciate this episode, but with all the uncertainty in the world right now, and I know we have a lot of really great people on this topic, what is one good thing that is happening personally or professionally that you're thankful for right now?

Jennifer Koziol (31:02):

I am always very thankful for my family. I live in a very fast paced, sometimes pretty interesting world as a veterinarian. I can always call home, talk to them, tell them about my cases and my days. So I'm pretty thankful to have my family and really the backbone behind me. I'm really thankful for that.

Host Lynsey McAnally (31:23):

It's always good to end Angus at Work on a good note and that one sounds like a great one. Thank you so much again for joining us. We really appreciate it.

Jennifer Koziol (31:31):

Yeah, absolutely. Thank you.

Host Lynsey McAnally (31:39):

Listeners, for more information on making Angus work for you, check out the Angus Beef Bulletin and the Angus Beef Bulletin EXTRA. You can subscribe to both publications in the show notes. If you have questions or comments, let us know at abbeditorial@angus.org and we would appreciate it if you would leave us a review on Apple Podcasts and share this episode with any other profit-minded cattlemen. Thanks for listening. This has been Angus at Work!