Breaking free from the chains of the past Where
truth moves faster than a Holstein calf No law
waiting on some printed page We're charting new
ground in the digital age From genomic codes
to robot facts We cut through the noise, no hold
them back not your daddy's dairy news tonight
we're sparking Welcome to the Bullvine Podcast,
where we dig deep into the hidden profit killers
lurking in your dairy operation. Today, we're
exposing the $2 .2 billion secret draining your
herd's potential, one winged thief at a time.
Sunshine and green pastures might look idyllic,
but they're hiding a war zone. We're talking
about horn flies siphoning 10 to 20 pounds from
weaning weights. Stable flies stealing 306 milk
pounds per cow annually and face flies spreading
pink eye like wildfire. In this no -nonsense
episode, we'll arm you with battle -tested strategies
from Kansas State University's latest research,
including the sanitation protocol cutting stable
flies by 80%, the insecticide rotation schedule
slashing resistance risk 65%, the economic threshold
numbers you can't afford to ignore, Dr. Roger
Moon from the University of Minnesota puts it
bluntly. You can't manage what you don't measure.
Fly counts are non -negotiable. We'll show you
exactly how to implement his monitoring system
and protect up to $300 per cow in lost productivity.
This isn't just pest control. It's profit protection.
Let's dive in. Welcome to the deep dive, folks,
where we pull back the curtain on the stuff that
really hits your farm's bottom line. And today...
We're not chasing yields or scrutinizing feed
rations. We're talking about something that buzzes,
bites, and generally makes life miserable for
your herd. And probably you too, let's be honest.
Definitely. We're diving deep into the financial
black hole that is fly infestations. Ever really
tallied up what those tiny terrors are actually
costing you? It's a figure that would likely
surprise, well, probably even the most seasoned
dairy producers out there. We're looking at a
staggering, get this, $2 .2 billion drain. Billion
with a B. Wow. On the U .S. cattle industry every
single year, all thanks to these winged nuisances.
So the real question for you listening today
is... Are flies silently picking your pocket,
cow by cow? Exactly. Forget the fly swatter for
a minute. This isn't just about the annoyance
factor, though that's bad enough. This is about
cold, hard economics. We're going to dissect
the real impact of these infestations on your
dairy and hopefully arm you with some actionable
intel to fight back. We're tackling the big offenders.
Horn flies. Those bloodthirsty stable flies.
Those eyeball -loving face flies. And even the,
you know, the seemingly harmless but surprisingly
problematic house flies. And for our listeners,
I mean, you're already juggling market prices,
milk components, a million other things, right?
Always. So our goal here is really to cut through
the clutter, focus on the critical data and strategies
that directly impact your profitability, and
just as importantly, the well -being of your
animals. Yeah, maybe give you one of those aha
moments. Connect what might seem like just...
a minor summer annoyance to some pretty significant
financial realities precisely okay 2 .2 billion
dollars it's just it's an astronomical number
let's try to bring that down to earth a bit maybe
to the level of an individual cow how does that
huge industry loss translate to what's happening
in say your barn or pasture okay good question
let's take the horn fly A real perennial pest.
The estimated cost per horn fly per cow per year
is around $1 .40. Now that sounds small. $1 .40
per fly, okay. The picture you heard on a warm
summer day, it's not unusual, unfortunately,
to see upwards of 200 horn flies on a single
animal. Easily, sometimes more. Exactly. So suddenly,
that seemingly insignificant $1 .40 per fly,
well, it multiplies out to nearly $300 in lost
production per cow. annually. 300 bucks a cow
just vanished because of flies. That's real money
disappearing, often without maybe a second thought.
It really is. Right. You might just think, yep,
it's a bad fly year and kind of move on. But
that casual observation is masking a serious
erosion of your potential earnings. Absolutely.
It's not just about the cows being itchy. It's
directly hitting the pounds of milk in the tank.
Yeah. And it even hinders the growth of your
replacement heifer. Yeah, which you've already
invested so much in. And the impact isn't solely
physical irritation leading to less grazing time
either. We see really distinct behavioral changes
in cattle when flies... population surge. Oh
yeah, you see it all the time. Think about the
classic signs. That constant tail switching,
the foot stomping. Yep. You'll notice that, especially
when stable flies are having a field day on their
legs, those things bite hard. Or the incessant
head shaking and ear flapping. Every dairy person
knows that dance, right? Usually prompted by
those persistent face flies buzzing around their
eyes, trying to get a snack of those secretions.
Exactly. And then you've got the herd bunching
up together in the pasture, almost glued side
by side, even when the sun is blazing down. Yeah,
trying to protect each other, I guess. Exactly.
That bunching, it's their natural defense against
the onslaught, but it's kind of a double -edged
sword, you know. How so? Well, in hot days, it
significantly exacerbates heat stress, which,
as you know, takes a further toll on milk production.
Right. More stress, less milk. And let's not
forget the cows seeking any respite they can
find standing waist deep in ponds or huddles
in the shade somewhere. Instead of eating. Instead
of being out grazing and converting that forage
into milk. Which brings us right to the fundamental
problem, doesn't it? All that energy the cows
are burning trying to get away from flies, all
that time they're not eating. Yeah. It directly
translates to reduced feed intake. And in this
business, I mean, it's a pretty simple equation.
Less feed in equals less milk out. It is that
simple. And when we drill down and actually quantify
the losses caused by each specific fly species,
the economic picture gets even clearer and, frankly,
maybe a bit more alarming. Okay, let's do that.
Let's start with hornflies, just given how widespread
they are and the sheer scale of their economic
impact over $1 billion annually across the U
.S. A billion dollars just from hornflies. Wow.
Makes you want to declare war, doesn't it? It
really does. So what's the direct hit production
from these guys? Well, for calves, we're looking
at maybe a 10 to 20 pound reduction in weaning
weight. Yeah. Research out of the University
of Nebraska has, you know, consistently shown
this. 10 to 20 pounds. Okay. Now, for dairy operations
raising their own replacement heifers, think
about that loss growth trajectory. You're already
pouring significant resources feed, caracta,
into getting those heifers to the optimal size
and weight for breeding. Yeah. Every day counts.
Horned flies essentially throw a wrench in those
plans. They can delay puberty, potentially impacting
their future milk production down the road. And
the economic threshold for horned flies at a
point where you really need to step in is around
200 flies per animal. 200. Okay, it sounds like
a lot, but when you're out there in peak fly
season, honestly, sometimes it looks like they're
wearing a second skin made of flies. It absolutely
can. Now let's switch gears to stable flies.
I always seem to draw their attention when I'm
doing chores around the barn. Those bites definitely
have a sting to them. Oh, they're vicious. They're
not just unpleasant for us. They're costing the
industry even more than horn flies a staggering
$2 .2 billion annually. The full number we started
with, yeah. That's them. And their impact on
production is substantial. We're talking about
an average daily gain reduction of 0 .44 pounds
per day in growing cattle. Nearly half a pound
a day. But what's particularly painful for dairy
producers listening is the milk loss. Studies
have shown that stable flies can lead to a loss
of up to 306 pounds of milk per cow every single
year. Whoa, 306 pounds of milk per cow. That's
like leaving money on the table every single
day. You got to think about that on a herd basis.
Exactly. Truly shocking, or maybe surprising
about stable flies, is their remarkably low economic
threshold, isn't it? Yeah, you mentioned that.
It's not like you need to see a massive swarm
before they start hitting production. Precisely.
It's surprisingly low, just five stable flies
per leg. Per leg can be enough to negatively
impact production. Five flies, seriously. Five
flies. That seemingly tiny number can accumulate
to a substantial amount of lost milk over a lactation.
It really underscores the need for, you know,
vigilant and early control measures. No kidding,
five flies. Okay, now what about those face flies?
They seem maybe less directly linked to a drop
in the milk tank, but man, they certainly drive
the cows. crazy buzzing around their eyes. Yeah,
they're incredibly irritating. And while their
direct impact on milk volume might be less dramatic
than stable flies, they still cost the industry
over $53 million annually. Still significant.
Still significant. Their primary damage really
comes from their role as vectors for disease,
most notably pinkeye. Ah, right. Pink eye. We're
looking at a potential 17 to 65 pound weight
loss associated with pink eye in growing cattle.
And in lactating cows that get infected, milk
production can plummet by as much as 25%. A quarter.
25%. That's a brutal hit if pink eye takes hold
in your herd. Ouch. It's huge. And it all comes
down to those irritating little face flies carrying
the bacteria around. So what's the tipping point
with them? When should you start to worry, start
taking action against face flies? The generally
accepted economic threshold for face flies is
around 10 to 14 flies per face. Once you consistently
see numbers in that range, the risk of pink eye
transmission really starts to escalate. 10 to
14, okay. They feed on those eye secretions you
see, and in the process, their kind of rough
mouth parts can actually create tiny abrasions
on the cornea. Oh, lovely. Yeah. Makes it much
easier for the Moraxella bovis bacteria, the
pink eye bacteria, to take hold. And as they
flip from cow to cow, they're effectively just
spreading the infection around the herd. Ugh.
So, okay, we've covered the direct production
losses, milk growth, but... It sounds like this
whole disease transmission aspect is like a hidden
multiplier for the financial damage. Exactly.
That's a good way to put it. Face flies, as we've
discussed, they're the prime movers in spreading
the bacteria behind pinkeye. But it doesn't stop
there. Horn flies also have a kind of nasty side
gig when it comes to the health of your young
stock. Oh, yeah. I wouldn't have immediately
connected horn flies to other issues beyond just
general irritation and maybe that lost weight
gain. What kind of trouble do they cause? Well,
horn flies can be a significant contributor to
mastitis in pre -partum heifers, so before they
even calf. In heifers? How? They tend to feed
around the teat ends, and their biting action
can create small lesions or wounds. These seemingly
minor injuries then become perfect little entry
points for opportunistic bacteria, particularly
Staph aureus. Staph aureus? Yeah. Not. Not what
you want. Definitely not. And the really concerning
part is that this can lead to infected quarters
even before those heifers enter the milking stream
for the first time. So you're potentially looking
at lost quarters impacting their lifetime milk
production, costing you down the line. Wow. That's
a long -term cost that's probably easy to miss
during the daily battles of fly season. Okay,
and then we've got the humble housefly. They're
just sort of everywhere, right? Buzzing around,
landing on everything. What's the real threat
they pose? They don't bite, at least. Right.
They don't bite, but don't let their non -biting
mouthparts fool you. Houseflies are essentially
flying fomites. Think of them like little dirty
sponges, if you will. They're mechanical vectors.
That means they can pick up a whole host of pathogens
on their bodies and legs and then just transfer
them to other surfaces. Think about them buzzing
around manure piles, then landing on feed bunks,
or even directly on your cows, maybe on milking
equipment. They're really efficient at transmitting
mastitis -causing bacteria and even the organisms
responsible for calf scours. So even the non
-biting ones are trouble. Definitely. So while
they're not directly causing the irritation of
a bite, they're certainly contributing to the
overall disease challenge on your farm. All right,
so the message is loud and clear. Flies are not
just a nuisance. They're actively draining our
profitability through reduced production and
increased disease. So... What's our battle plan?
How do we as proactive dairy professionals start
to gain the upper hand in this ongoing war? Okay,
the battle plan. The very first and most critical
step is to recognize that early spring monitoring
is absolutely essential. You have to know what
you're dealing with and when. Don't wait until
you're swatting clouds of them. Exactly. Waiting
until you're swatting away clouds of flies means
you're already playing catch up and you've likely
already suffered some economic damage. It's kind
of like waiting for your somatic cell count to
skyrocket before thinking about your mastitis
protocols, right? Yeah, too late then. Reactive.
You're reacting instead of preventing. An effective
fly management program needs to be comprehensive.
It needs a multi -pronged approach. There's really
no single silver bullet here. Okay, multi -pronged.
So where do we even begin? What's the, like...
The bedrock of a solid fly control strategy.
The absolute foundation, the non -negotiable
first step, is sanitation and environmental management.
This is often the most impactful strategy and,
surprisingly maybe, it can also be the most cost
-effective in the long run. Makes sense. It's
all about eliminating the places where flies
breed. Simple concept. No breeding sites, fewer
flies. Right. If you can disrupt their life cycle
at the larval stage, you're way ahead of the
game. So what are the key areas we need to be
laser focused on in terms of sanitation? Where
do they breed? Manure management has to be top
priority, especially for stable flies and house
flies. During fly season, you should really aim
for weekly or maybe even more frequent clean
out of barns, pens, loafing areas. Weekly. Pay
close attention to those often overlooked corners
and edges. So, you know, fence lines where manure
and bedding tend to pile up. The edges of feed
bunks where spilled feed gets mixed in. And particularly
calf housing, calf hutches, group pens, they
can become fly breeding havens if not meticulously
managed. Yeah, those damp corners. Exactly. In
fact, there was a 2023 study out of Kansas State
University. It demonstrated an impressive 80
% reduction in stable fly populations simply
through consistent weekly manure removal. 80%.
Just from cleaning up manure more often? That's
a game changer. It's a massive return on a relatively
simple practice. Okay. And what about bedding?
We rely heavily on straw in our heifer pens,
for example. Yeah, and soiled bedding, particularly
straw but other types too, creates an ideal habitat
for fly larvae. It provides the moisture and
the organic matter they need to thrive. Right.
So regular bedding changes are crucial, especially
during the warmer, more humid summer months.
Don't underestimate how rapidly fly populations
can explode in damp soiled bedding. Noted. Okay.
And I'll admit, we can sometimes be a little
lax about promptly... Cleaning up spilled feed
around the bunks. Sounds like we need to tighten
up our protocols there as well. Absolutely. Spilled
TMR, silage, grain, especially when it gets wet
and starts to ferment a little. Prime real estate.
That is another prime fly breeding ground. Those
moist, nutrient -rich pockets are exactly what
fly larvae are looking for. Consistent and thorough
cleanup is really essential. Okay. Manure, bedding,
spilled feed. Anything else in the environment
that can contribute to a thriving fly population?
Water. Water management. Yep, another critical
piece of the puzzle. Promptly repair any leaky
waters or pipes. You don't want those constant
wet spots. Right. Ensure proper drainage around
all buildings to prevent those stagnant wet areas
where flies love to lay their eggs. Even seemingly
small, consistently damp spots can support a
surprisingly large fly population. And then there's
composting. If you're composting manure, doing
it correctly. That means maintaining internal
temperatures between, say, 131 and 170 degrees
Fahrenheit. Hot enough to kill them. Exactly.
Regularly turning the piles to aerate, ensuring
a moisture content between 40 and 65 percent
that can effectively kill fly larvae while also
producing a valuable soil amendment. So, win
-win. Good point. Okay, so sanitation forms the
base of our defense. But even with the cleanest
farm, let's be real, you're likely still going
to encounter some flies. Oh, absolutely. Eradication
is usually unrealistic. So how do we determine
when those populations have reached a point where
we need to deploy other control measures? How
do we know when to act? That's where diligent
monitoring comes into play. As the renowned entomologist
Dr. Roger Moon from the University of Minnesota
has famously stated, and it really bears repeating,
you can't manage what you don't measure. Fly
counts are non -negotiable. Can't manage what
you don't measure, okay? You need to establish
an early warning system by actively monitoring
fly populations. Start as soon as the weather
begins to warm up in the spring. Don't wait.
Okay, so how do we actually do these fly counts?
I mean, I can't imagine trying to individually
tally every fly on a cow running past. No, thankfully
not. There are several practical and relatively
straightforward methods. Sticky traps are excellent
for tracking housefly activity, particularly
inside barns and milk rooms. Those sticky ribbons.
Yeah, or larger sticky traps. You hang them strategically,
monitor the number caught over, say, a week,
and track the trend. Spot cards are another simple
tool, especially for houseflies. Spot cards?
Plain white index cards. You place them in areas
where flies tend to rest walls, ceilings, rafters.
After a week, you count the fly specs. If you
get 100 or more spots, that generally indicates
a significant house fly problem. Okay, simple
enough. And then there are direct observation
counts for the flies on the animals. For horn
flies, you'll typically observe one side of several
animals in your herd, count the flies, and then
double that number to get an estimate per animal.
Right, because they're mostly on the back and
sides. That's exactly. For stable flies, focus
your attention on their lower legs, front legs
usually. That's their preferred feeding site.
Count the flies per leg. Okay, remembering that
low threshold of five per leg. Right. And for
face flies, well, you literally need to observe
the faces of your cows and count the number of
flies present around the eyes and muzzle. Got
it. So once our monitoring efforts, the sticky
traps, spot cards, direct counts, indicate that
we've reached those economic thresholds we talked
about earlier, that's when it's time to bring
out the more targeted interventions, the chemical
control option. Exactly. But, and this is absolutely
critical, your approach needs to be tailored
to the specific fly species you're targeting.
Right. Not one size fits all. Definitely not.
What's highly effective against stable flies
might be completely useless against horn flies
and vice versa. It all comes down to their different
behaviors and life cycles. All right, let's break
down the chemical arsenal then by fly type. For
those premise flies, the stable flies, and house
flies that spend most of their time off the animal,
what are our most effective chemical controls?
Okay, this is a crucial distinction. Insecticide
ear tags and poron treatments are generally ineffective
against stable and house flies. Because they're
not on the cow much. Precisely. They spend most
of their time away from the animal, resting on
walls, ceilings, fences, whatever. So you need
to focus on treating those areas where they congregate
and breed. Makes sense. So what works? Premise
or residual sprays. You apply these to walls,
posts, ceilings, other surfaces where these flies
like to land and rest. These typically provide
control for several weeks, but you'll likely
need to reapply them every two to three weeks
depending on the product and the conditions.
Space sprays, mists, and fogs. Those can offer
a rapid knockdown of adult flies during a really
heavy infestation. Good for immediate relief,
maybe. But no lasting effect. Right. Little to
no residual control. Yeah. And then there are
various types of baits. Granular baits, bait
stations. You place these strategically in areas
where flies tend to hang out. Just make absolutely
sure they're inaccessible to feed, water, and
the animals themselves. Safety first. Always.
Okay, so targeting their environment is the key
strategy for those premise dwellers, like stable
and house flies. Now, what about the pasture
flies, the horn flies, and face flies that spend
a significant chunk of their lives on the cattle?
Right. For these species, on -animal treatments
are much more effective because the flies have
prolonged contact with the insecticide on the
cattle. So ear tags come into play here. Insecticide
ear tags are a... Very popular and, you know,
convenient option. They typically provide around
12 to 15 weeks of control, sometimes longer depending
on the tag and fly pressure. That covers most
of the season. Usually. For face flies, it's
generally recommended to use two tags per animal,
one in each ear, to provide better coverage around
the head where they tend to congregate. Good
tip. Two tags for face flies. But a critical
point with ear tags. Don't apply them too early
in the fly season. Wait until you actually reach
that economic threshold. Remember, 200 for horn
flies. Right. Don't waste them. Exactly. Maximize
their effectiveness throughout the peak fly period.
Poor insecticides can offer maybe 28 days, roughly,
of protection. They're generally effective against
horn flies and can also provide some control
of face flies, especially with proper application
along the top line. Sprays offer a quick knockdown,
but require pretty frequent reapplication to
maintain adequate control. Can be labor intensive.
Duff bags and back rubbers. Those are good options
for self -application, particularly when you
place them strategically in forced -use areas,
like the entrances to water sources or mineral
feeders where cows have to contact them. Make
the cows treat themselves, basically. Kinda,
yeah. And finally, feed -through products are
an interesting tool. These are larvicides added
to the animal's feed or mineral. They pass through
the digestive system. And kill the larvae in
the manure. Exactly. They kill fly larvae developing
in the manure. However... To be truly effective,
you need to start using them about 30 days before
the anticipated start of fly season. Get ahead
of it. Yeah, and you have to ensure consistent
consumption across the entire herd. If some cows
aren't eating it, it won't work well. Right.
Consistency is key there. Okay, so we've got
a whole arsenal of tools at our disposal. Sanitation,
monitoring, sprays, tags, pour -ons, feed -throughs.
But I know a major concern among producers these
days, and rightly so, is the development of insecticide
resistance. Huge concern. Absolutely critical.
How do we prevent our go -to control methods
from becoming, well, useless over time? That's
the million -dollar question, isn't it? Yeah.
And we need to take it very seriously. Horn flies,
in particular, have a notorious, really rapid
ability to develop resistance to insecticides.
We have to be proactive in our resistance management
strategy. So it's not just if, but when, if we
don't manage it right. Pretty much. But there's
good news. Research, again from the University
of Nebraska, has clearly shown that rotating
pyrethroid insecticide ear tags with organophosphate
tags every season, just switching classes each
year, can reduce the risk of resistance development
by a significant 65%. 65 % reduction just by
rotating tag types each year. That's powerful.
It's a substantial benefit from a relatively
simple change in practice. You just have to plan
it. Okay. What are the key strategies then for
winning or at least, you know, not losing this
ongoing resistance battle? OK, number one, rotate
your chemical classes annually. Like we just
said, don't rely on the same type of insecticide
pyrethroids, organophosphates, macrocyclic lactones
year after year for your tags or even your sprays
if you use them heavily. Make a conscious effort
to switch between classes. Got it. Rotate classes
yearly. What else? Secondly, as we touched on
with ear tags. Timing your applications correctly
is crucial. Don't be tempted to put those tags
in at the first sign of a fly in May. Wait until
you reach that economic threshold around 200
horn flies per animal before applying those on
animal treatments. Less exposure time for the
flies. Exactly. It minimizes the exposure of
the fly population to the insecticide and slows
down the selection pressure for resistance. And
this next point is absolutely vital. Maybe the
most overlooked. Okay. Remove those insecticide
ear tags after the main fly season has ended.
Don't leave them in all winter. Please don't.
Leaving them in over the winter. when fly populations
are naturally very low, actually helps to select
for those few individual flies that happen to
have some level of resistance. You're basically
breeding resistant flies for next year. Wow.
Okay. So make it a standard practice. Physically
cut out those tags after the first hard frost.
Mandatory. Should be part of the fall checklist.
And finally, don't put all your eggs in one basket.
Don't rely solely on one single control method.
Embrace an integrated pest management IPM strategy.
The multi -cronged approach again. Exactly. Strategically
combine that foundational sanitation, the diligent
monitoring, and the judicious use of different
chemical and maybe even non -chemical control
tools like traps or biological controls where
feasible. Right. Hit them from multiple angles.
Okay, so wrapping this up, the core message here
seems clear. Effective fly management isn't just
about keeping the guys from getting too annoyed,
though that's important for welfare. It's really
a direct and crucial defense of our milk checks
and the overall profitability of our dairy operations.
Precisely. It's an investment, not just an expense.
We strongly encourage you, everyone listening,
to critically evaluate your current fly control
protocols. Are they working? Are you measuring?
Are you rotating? Yeah. Consider implementing
this comprehensive, multi -pronged approach.
Combine rigorous sanitation practices with consistent,
accurate monitoring. And then strategically deploy
your chemical control options, always keeping
those principles of insecticide resistance management
at the forefront of your decision making. So
as you're walking through your barns and pastures
later today, maybe tomorrow morning, take a closer,
more analytical look at those buzzing, biting
pests. Don't just swat them away. Yeah, count
them. Count them. And really consider the potential
financial gains, both in terms of increased milk
production, better growth, and reduced animal
health costs that could come from actively and
effectively crushing those fly infestations.
What could that extra margin mean for the long
-term sustainability and success of your dairy
operation? It's definitely something worth thinking
about. digging into for your specific situation.
Absolutely. A topic worth a deep dive for every
single one of us in the business. If you're ready
to stop being a fly buffet and start reclaiming
your milk check, we've got your battle plan.
Implement weekly manure removal from Kansas State's
2023 trials. Rotate pyrethroids with organophosphates
annually. Start feed -through larvicides 30 days
preseason. Visit thebullvine .com. slash fly
control for our free monitoring checklist and
resistance rotation calendar. Help other dairy
producers combat this $2 .2 billion problem.
Hit share and tag a colleague who needs to hear
this. Next week, we're exposing the methane to
money pipeline, how forward -thinking dairies
are turning climate regulations into $1 ,200
head profit opportunities. Until then, remember,
in the battle against winged thieves, knowledge
is your best insecticide. Keep milking for it.