Absarokee Animal Hospital, PC

07/09/2026

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Not all wound care ointments and sprays are created equal. Register for our free webinar with Dr. Carrie Hammer and Dr. Nikki Scherrer to learn strategies for basic wound healing and the effectiveness of common disinfectants, sprays and creams used to treat equine problems. We'd love to see you there! https://tinyurl.com/3n66xtw6

06/08/2026

Edit: We are functioning normally again! Well, as normally as we ever function. They got the wires repaired. 5pm 6/8/26

6/8/2026 2:45pm. The clinic has no phone or internet for an indeterminate length of time due to an oopsie with the fiber installation. Text me if you need something! 🙄

06/05/2026

Ever since I wrote about New World screwworm, one question keeps coming up over and over again.

"Okay, but how exactly do they make the flies sterile?"

And honestly, it is one of those situations where the real answer somehow sounds stranger than the conspiracy theories. If somebody explained this entire program without evidence, most people would assume they were joking. Because the official strategy for protecting the cattle industry can essentially be summarized as follows: raise millions of flesh-eating flies, expose them to radiation, load them onto airplanes, release them across the countryside, and somehow save millions of cattle. Every single one of those steps is scientifically accurate. Every single one sounds ridiculous. Yet together they form one of the most successful pest eradication programs ever developed.

Let's start at the beginning. Scientists first raise enormous numbers of screwworm flies in specialized production facilities. And when I say enormous numbers, I do not mean a few cages sitting on a shelf somewhere. I mean millions upon millions upon millions of flies. Entire facilities exist for the purpose of producing screwworms. Adult flies lay eggs. The eggs hatch into larvae. The larvae are raised on carefully designed diets that provide exactly the nutrients they need. They grow, pupate, and eventually develop into adult flies. Then the cycle starts all over again. Somewhere there are highly educated professionals whose daily responsibilities include making sure enough screwworm larvae successfully develop into adulthood. Imagine trying to explain that career path to your high school guidance counselor. "I would like to dedicate my life to raising vast numbers of flesh-eating flies." That conversation probably requires a little additional explanation.

The really interesting part happens during the pupal stage. If you remember your insect biology, the pupa is the stage where the insect is transforming into an adult. It is basically the insect equivalent of being locked in a room undergoing a complete biological renovation project. During this stage, scientists expose the developing insects to carefully controlled doses of radiation. Most commonly, this involves gamma radiation or X-rays. Now before anyone starts imagining glowing radioactive superflies capable of lifting small vehicles, that is not what happens. The goal is not to create mutant insects. The goal is much more precise than that.

The radiation damages the chromosomes inside the developing reproductive cells. Think of chromosomes as instruction manuals. They contain the genetic information needed to produce healthy offspring. When scientists expose the pupae to carefully calibrated radiation, those instruction manuals become damaged. The fly itself still develops normally. It still emerges from the pupal case. It still flies. It still eats. It still behaves like a perfectly normal screwworm fly. In fact, if you put a sterile fly and a fertile fly next to each other, you generally would not notice a difference. The fly does not know it is sterile. The female fly certainly does not know it is sterile. The only thing that changes is that when reproduction occurs, viable offspring are not produced.

And that is where the science becomes incredibly important. Scientists are not trying to create weak flies. Weak flies would be useless. If the radiation dose is too high, the male flies become less competitive. Wild females will choose healthier wild males instead. The whole program falls apart. If the radiation dose is too low, some fertile offspring may still be produced. That is also a problem. So researchers spend enormous amounts of time determining exactly the right radiation dose. The fly must remain healthy enough to compete successfully for mates while being unable to produce offspring. Essentially, scientists are trying to create the world's most attractive unsuccessful father. It is an oddly specific scientific goal, but it turns out to be incredibly effective.

Once the sterile flies emerge as adults, they are prepared for release. Historically, many of these releases have been conducted from aircraft. Which means there are pilots whose cargo consists of millions of flies. Imagine being responsible for that paperwork. Somewhere an aviation employee asks what is on board, and the answer is, "Approximately several million sterile screwworm flies." There cannot be very many jobs where that sentence sounds completely normal. Yet aircraft have played a critical role because screwworm control requires covering huge geographic areas. You cannot simply release a few flies and call it good. You need overwhelming numbers.

And this is where the entire strategy hinges on one very important piece of screwworm biology: female screwworm flies generally mate only once. Just once. That fact is the foundation upon which the entire eradication program was built. A female fly does not know whether a male is fertile or sterile. She simply finds a mate. If she mates with a fertile male, offspring are produced. If she mates with a sterile male, no viable offspring result. Since she usually does not go looking for another mate afterward, her contribution to the next generation is effectively finished.

Now imagine what happens when millions upon millions of sterile males are released into an area. Suddenly the odds begin shifting. More females encounter sterile males. More females produce no offspring. The next generation becomes smaller. Then another wave of sterile flies is released. More females mate with sterile males. The population shrinks again. Then another release occurs. And another. And another. The process continues generation after generation until the wild population gradually collapses. Scientists are not killing every fly. They are not poisoning entire ecosystems. They are not trying to exterminate every insect they can find. They are specifically targeting the reproductive biology of one species.

From a scientific perspective, it is actually elegant. Instead of fighting nature head-on, the program uses the fly's own biology against it. The fly's reproductive strategy becomes its weakness. The same trait that helped screwworms succeed for thousands of years becomes the reason they can be controlled. It is essentially biological judo. Rather than using brute force, the program redirects the fly's own life cycle against itself.

What makes this even more impressive is that the approach is incredibly selective. Broad-spectrum insecticides can affect many different insects. The sterile insect technique targets one species. Honeybees continue being honeybees. Butterflies continue being butterflies. Pollinators continue doing pollinator things. The screwworm population simply runs out of future generations. As far as pest control goes, it is remarkably precise.

Honestly, what amazes me most is the sheer amount of science hiding behind something that sounds so absurd. Somewhere there are entomologists, geneticists, radiation biologists, veterinarians, animal health specialists, population ecologists, pilots, engineers, and technicians all working together on a project whose basic mission statement could be summarized as: "Create millions of flies that never become fathers." These are highly trained professionals using advanced genetics, radiation physics, insect physiology, reproductive biology, and population dynamics to solve a major agricultural problem. Yet when you reduce the entire program down to one sentence, it still sounds like something somebody invented as a joke.

And yet it works.

In fact, it worked so well that New World screwworm was eradicated from the United States for decades. One of the most destructive livestock parasites in North America was pushed out through a strategy that sounds like it belongs in a science fiction novel. Which means that somewhere right now, millions of sterile flies are being released as part of one of the most important livestock protection programs in the world. The flies think they are out there living perfectly normal fly lives. The scientists know they are actually participating in one of the greatest pest-control programs ever created. And somehow, against all odds, the entire thing continues to work because of a remarkably simple idea: if enough flies never become fathers, eventually there are no more flies.

06/05/2026

There has been a lot of discussion lately about how New World screwworm got back into the United States, and whenever something like this happens, the internet immediately does what the internet does best. Some people start sharing facts. Some people start sharing rumors. Some people decide the answer probably involves secret laboratories, government conspiracies, international coverups, and enough plot twists to keep a Hollywood screenwriter employed for years. So before the story grows any larger than it already has, let's talk about what we actually know. Not theories. Not rumors. Not things somebody's cousin's neighbor's uncle posted online. Just the facts.

The first thing to understand is that New World screwworm did not suddenly appear out of nowhere. It did not magically materialize in Texas. It did not escape from a laboratory. It did not arrive hidden inside a shipment of mysterious cargo. The explanation is actually much less dramatic and much more frustrating. It spread. That's it. Decades ago, the United States successfully eradicated New World screwworm through one of the most remarkable pest-control programs ever developed. Scientists discovered that female screwworm flies generally mate only once during their lifetime. So they began raising millions of male flies, sterilizing them, and releasing them into the environment. When a female mated with one of those sterile males, she produced no offspring. Repeat that process enough times and the population collapses. It sounds completely absurd when you first hear it. It sounds like the sort of idea somebody comes up with after not getting enough sleep. Yet it worked so well that many ranchers, veterinarians, and livestock producers alive today have never actually seen a case.

But there is an important difference between eradicated and extinct. Eradicated means something has been removed from a particular area. Extinct means it is gone everywhere. Screwworm was eradicated from the United States. It was never extinct. The fly continued to exist farther south, and for decades animal health officials maintained what was essentially a biological barrier through surveillance programs, monitoring efforts, and sterile fly releases. Think of it like a fence. Just because your cows are on the correct side of the fence today does not mean you stop checking the fence tomorrow. As long as the cattle still exist, the fence still matters. The same principle applied to screwworm.

What happened over the past several years is that the fly began moving north through Central America and then into Mexico. Not secretly. Not overnight. Not unexpectedly. People in veterinary medicine, animal health, livestock production, and government agencies had been watching this happen for quite some time. In fact, one of the biggest misconceptions I keep seeing online is the idea that we somehow quit fighting screwworm years ago and suddenly remembered it existed once it reached Texas. That simply is not true. The sterile fly program never stopped. Millions upon millions of sterile flies continued to be produced and released while the parasite was moving northward. USDA was already releasing approximately 100 million sterile flies every week before the recent Texas detection. Let that number sink in for a moment. One hundred million flies. Somewhere there are scientists whose professional responsibility is essentially ensuring that flies have unsuccessful dating lives. It sounds ridiculous because it is ridiculous. It is also remarkably effective science.

The problem was not that nobody was trying. The problem was that biology can be stubborn. Anyone who has ever dealt with calf diseases understands this. You can vaccinate. You can improve biosecurity. You can monitor animals closely. You can work with your veterinarian. You can do everything correctly. And sometimes disease still spreads. That does not mean the efforts were pointless. It does not mean nobody cared. It means that living organisms have an annoying tendency to continue trying very hard to stay alive and reproduce. Screwworm flies are apparently no exception.

Another rumor I keep seeing is that Mexican cartels somehow caused the sterile fly program to stop. Again, there is no evidence supporting that claim. Now, are there areas of Mexico where security concerns can make animal-health work more difficult? Certainly. There are regions where surveillance, monitoring, inspections, and disease-control efforts can face additional challenges. That is a real issue. But that is very different from saying the entire screwworm program stopped because of cartels. The evidence shows the opposite. Sterile fly releases continued. Surveillance continued. Monitoring continued. Additional facilities were built. Resources were expanded. New dispersal centers were opened. As the threat increased, the response increased too.

The reality is much less exciting than the conspiracy theories. Flies do not understand borders. They do not stop at customs. They do not fill out paperwork. They do not arrive at a checkpoint and politely announce that they appear to have entered Texas and should probably turn around. They are flies. They reproduce. They move. They spread. Sometimes they are carried by animals. Sometimes by vehicles. Sometimes by weather systems. Sometimes simply by doing what flies have done for thousands of years. That is what makes them difficult to control. You are not fighting an enemy that follows rules. You are fighting biology itself. And biology has been practicing for a very long time.

The good news is that the current situation is not being ignored. Quite the opposite. USDA and animal health officials are responding aggressively because they know exactly what is at stake. Sterile fly releases have been expanded. Surveillance has increased. Quarantine zones have been established. Wildlife and livestock monitoring programs are active. Additional production facilities are being developed because officials understand that the faster the response, the better the chance of preventing widespread establishment. The goal right now is not panic. The goal is eradication. Again.

Honestly, one of the biggest lessons from this entire situation is that nature is persistent. You can win a battle. You can win it for decades. You can create one of the most successful eradication programs in agricultural history. Yet if the pest still exists somewhere else, you have to remain vigilant. Because flies do not care about political opinions. They do not care about social media arguments. They do not care about conspiracy theories. They do not care whose fault everyone thinks it is. They are simply trying very hard to make more flies.

Which is why, right now, veterinarians, entomologists, ranchers, livestock producers, wildlife specialists, researchers, and animal health officials are all working toward the same goal. Their strategy remains surprisingly similar to the one that worked decades ago. Raise millions of sterile flies. Release them into the environment. Let them compete with fertile flies. Gradually collapse the population. Honestly, if somebody described that plan without telling you it actually worked, it would sound like the plot of a particularly strange science fiction novel. Yet it remains one of the most successful animal-health programs ever developed.

And if history repeats itself, there is a very good chance that decades from now another generation of veterinarians and ranchers will be talking about screwworm the same way many of us used to talk about it: as something they learned about in a textbook but never expected to see in real life. That is the goal. And strangely enough, achieving that goal still depends on an army of flies whose greatest contribution to society is never becoming fathers.

05/21/2026