Person on horseback galloping between to groups of cattle



Well, welcome back to the Pastured Profit Podcast.

I'm Travis Taylor, Livestock Specialist for the Golden Plains area, CSU Extension here in Northeast Colorado.

And I'm joined today by my fellow podcaster, Scott Stennett, who hails from the Kit Carson County office in Burlington, Colorado.

And today, Scott, we got a topic that's on my mind.

As I drive down the road, I see groups of cows starting together in the corners of pastures and yearlings running across the prairie.

And it's that time of year where we have issues with fly control.

I'm going to pose the question to you as to why is this fly control so important?

Well, Travis, you know, not only is it bugging our calves, so to speak, no pun intended, but it should bug us in our finances as cattle producers because flies are just one of those kind of sneaky financial impacts to the bottom line of the herd.

There's been plenty of research done out there probably over the past 50 years on flies and fly control and what it means.

But on the economic side, we found out through the whole beef industry that it can be a one point seven five billion dollar in losses to the beef industry as of 2000, 2021.

So it's pretty significant.

Some of the things that the individual types of flies can do as far as their effects, causing annoyances to the point where and blood feeding, which is our big problem, causing losses in weight gain.

So these calves on the cow side, the cow trying to gain weight back while she's nursing to get back in good body condition, replacement heifers that we're trying to grow, all of those can be significantly affected by flies.

And financially, it's that loss of weight gain.

Well, I think particularly this year, when you talk about 2021 prices compared to what we believe we're going to see here in the fall of 24, it's a definite significant impact to the producers in our area of the state, Scott.

So which flies, Scott, are we talking about and how exactly does each type affect the herd?

Well, like I mentioned, our blood feeding flies are kind of our number one culprits.

And so we're talking about horn flies and stable flies out here in the High Plains.

The horn flies, those are the ones that are black and you usually see them on the back, the sides and the belly of our animals.

What they tend to do is they've got only about a 10 to 20 day lifespan.

But in that lifespan, every day, every fly is going to feed.

They're going to make a bite and ingest blood somewhere between 24 to 38 times in a day.

Do you think about, you know, if you've ever gotten a mosquito bite or even if you've been bit by a biting fly, multiply that by several hundred that could be on one individual animal doing that, you know, those that many times a day.

I mean, it becomes a pretty significant annoyance, plus the fact that they're actually taking blood from the animal.

And our other one are stable flies, and those are the ones we usually see lower down on the legs.

And they'll do some biting as well.

And the leg is a little bit even more sensitive.

I mean, think about if you get the mosquito bite down on your ankle, how much that itches.

So it's the same type of scenario for our cattle.

And so stable flies as well can cause some issues there.

We also have heel and face flies that can get out there and they do some other things.

But I want to focus on these two blood feeders.

So let me give you a couple of financial examples of why they're annoying.

So there's been, like I said, some studies done over the past 50 years on and off of, you know, what's the impact.

Most of these studies, they isolate these two species and they study each of them individually.

But we found out that we can reduce weight gains in young calves as much as 15 percent due to high horn fly loads. 18 percent loss of weight gain in heifers that we're wanting to keep for replacements.

Cows over the summer that are nursing, they may come in at the end of the summer 50, 60 pounds lighter than a set of cows that have been treated for flies.

And as a result, I mean, we use 100 to 120 pounds of weight loss as a one body condition score.

So they're losing half a body condition score due to flies or they're not gaining, I should say, that half of a body condition score.

So they're behind, you know, and you take this and you take put it in financial terms.

So on a horn flies, if you know, if you got 600 weight calves and they are 15 percent behind where they should be, you know, we're losing 91 to maybe one hundred thirty dollars.

At two dollars and sixty cents a pound, which is what I looked at the other day is as the going rate for the six weight calves.

Stable flies just about as bad.

One of the studies that we looked at shows that you can lose point four four.

So four tenths of a pound a day.

Is not gained, so it's a reduced gain.

But if you take that over, say, 90 days at point four four pounds, we've lost another hundred dollar bill on those calves.

And I shouldn't say loss, we're more along in the lines that we've failed to make, is what I should say.

But in this economy, you know, if you've got a hundred head of calves and you're leaving a hundred dollar bill behind from each one of them, that adds up pretty quick.

Yeah, I think you're right there.

It's not that we we don't necessarily see it, but we're not getting the total economic benefit we could from having those where we need to.

So we know that they're aggravating the cows.

We know that they're decreasing weight gain.

We know that we're having issues with other issues that come up because those flies are driving them into water holes.

And we see things like foot rot and we see things like pink eye become more prevalent.

But a lot of this can be helped if we can help control these pests.

What are some of the ways you would recommend we go about or research would say we need to do to control flies in our cow herds?

Well, the fly control is is really simple.

And by the time that this podcast goes out, a lot of the flies are really starting to to hit what we call an economic injury level.

That's where we get a number of flies that are going to cause these gains to be decreased.

So, for example, on horn flies, we're talking 200 or more flies on the body on those stable flies down on the legs.

We're talking about 20 total, so about five per leg, four legs, hopefully.

And we've got about five on each leg.

But, yeah, you know, they're going to be going to places.

They're not going to be eating.

They're going to cause all these other issues.

So the first thing is we want to try to get ahead of that economic injury level.

If you go out there and you see that you've got 200 plus already on the sides of now, you're now you're behind.

But you can what we can hopefully do is we want to rid our cattle of these flies and we want to break that fly lifecycle.

That's kind of the two keys to what we're doing.

And so we can do our basic insecticides.

You know, we can go out and we can use an insecticide spray.

You know, that used to be the big thing.

I mean, when I was a kid, I still remember, you know, driving by a pasture.

And you see cattlemen out there with a with a spray rig spraying down a group of cows that are all bunched up in a corner or bringing them into a lot so they can do that.

So we can do that.

We can pull out the passive fly controls, things like the big oilers and the powders and the rubs, places that the cattle can come by on their own and do that in our big pastures.

We usually see that around our where our minerals and maybe our water is, you know, they come by.

They'll use it as they're coming to get mineral.

They're coming to get water.

We can do some other fly controls can definitely do.

There are some full, full pest pesticides that we can use or parasitic side that should use that have insecticides in them for the flies and other externals, as well as the anthelmintics for the internals.

And so we can use those and they may come either in our now are kind of our go to is the poor ons.

But we also there are also some slow dissolve, slow the reese boluses that you can give that that are being used out there, as well as some injectables.

Once again, if we can, we can stay away from an injectable from a BQA point.

You know, that's one less needle poke in that animal.

So that's probably a good thing.

And so that usually tends to take care of the live or the living flies that are already adults that are there tends to keep them away from our animals.

But the other thing we want to do is want to break that that life cycle.

So to break that life cycle, we can use what are called insect growth regulators.

So IGRs and IGRs are some products that are out there that they're they're meant to help prevent the larvae that next generation for making it to adulthood.

And most common for a long time were IGRs that were feed through.

They could be mixed in feed for animals that are in a lot or in a feedlot.

It can be put in a lick tub.

And but, you know, a little bit of that is kind of inconsistent.

You know, one day they may take in a lot.

The other day, the next day, they might not take in as much.

But there are some newer products now that are are poor on IGRs.

So they're an insecticide with an IGR and they're in a poor on form.

So we know that each animal is going to get the individual dose that they need.

And so, like I said, that's going to prevent that larvae from becoming an adult in that next generation.

So, you know, 10 to 20 days on these flies.

So if you do that, hopefully we should see fly numbers decrease within three weeks.

And hopefully the rest of that month, if we break that generational cycle, we should be a little more on the fly free side.

So like you're saying, it's important to get started early.

I know that's one of the things we always do.

We don't worry about it until we see it.

But planning for fly season, I think, is just as important so that we can get started early.

And, you know, one of the things that I think is important when we talk about whether it's your insecticide ear tag or your poor on or what it is, we probably need to rotate through some of those chemicals so that we don't build up resistance in the flies or the parasites that we have.



Just like any other insecticide, parasiticide product that we use, they can create resistance within a subgroup that's a population that's living on your place.

And yeah, if you're using the same thing year after year after year, you know, they they could very easily learn to become resistant to it.

And the strong ones will survive.

And if you don't rotate your insecticides, like I said, your ear tags and whatnot, then, yes, we'll definitely have to come back and change some things out because we're going to have some resistance build up.

So if you were to give our producers a one-two punch on what to do for fly control, what would your recommendation be to our producers as far as maybe two quick things they need to think about with their fly control process?

Well, I think number one is do some observation, see where you're at.

You know, if you're already past an economic injury level, that EIL is high, then, yeah, we want to take care of the immediate problem.

If we're not, then we can do some, you know, some planning for that next generation.

We might can back off a little bit.

But treat what you've got and then work on breaking that life cycle.

So I would say any type of insecticide you can use that's got a long lasting effect, maybe externally on the skin, and then use some IGR products to help prevent that next generation of flies from coming around.

But the big thing, you know, consult with your veterinarian.

They'll know which products are working best in the area.

And but essentially they're cost effective.

You know, if you think about the fact that these, the loss of what you could have made is $100.

There was a survey done in Texas and Tennessee.

So two different kind of sets of cattle producers there.

But anywhere from nine and a half to $12 was the cost to do fly control for the summer.

But if I can put down, you know, a $10 bill and get $100 back at the end in the fall, I'm probably going to do it.

So I think they should really think about it on an economic level as much as just an animal health level.

Well, I think that's great advice, Scott.

And I think that wraps up this session of our Pasture to Profit podcast.

I'm Travis Taylor.

And if you have any items that you'd like to see discussed here, or you have questions on fly control, you can reach me at the Yuma County Extension Office in Ray, Colorado at 970-332-4151.

And Scott, if they need to get ahold of you, where can we catch you?

Yeah, here in Burlington, Colorado at the Kit Carson County Extension Office.

Number here is 719-346-5571.

So reach out to us if you have something you'd like discussed on the Pasture to Profit podcast.

Or if you need some help planning your fly control, give us a call.

We'll see you soon on our next Pasture to Profit podcast.