Terrie and Steve Moss putter around their ranch, Trophies Unlimited Whitetail, in a Kawasaki utility vehicle, peering through binoculars at the hundreds of graceful animals they own. In one pen, a handful of two-year-old bucks with rut-thickened necks and broad backs square off, antlers clanking and parrying. Nearby, others laze in the shade of post oaks whose trunks have been scraped down to the grain by antlers shedding velvet.

The star, Eddie Ray, has his own pen, stocked with a harem of 22 does. “I wake up and look out there at Eddie Ray first thing in the morning,” says Steve. Eddie Ray has a magnificent rack, with wide, outward-sweeping beams bristling with an armament of kickers, flyers, and drop tines crowding like live oak branches.

Eddie Ray, like most of the animals on this ranch outside Chico, has never met his father; he was conceived by way of frozen semen that arrived in the mail. Terrie and Steve artificially inseminate many of their does with this high-dollar substance and sell the resulting progeny to outfitters and other breeders. They’ve even gotten into the supply business themselves; Eddie Ray’s semen goes for $1,250 a straw, a fraction of a teaspoon. “Used to be that if you had a deer this big, he’s five years old,” Steve says, pointing to a buck in a nearby paddock. “I have a yearling with a two-hundred-inch rack. It’s all about genetics.”

Thanks to these innovations, the Texas deer-breeding industry has thrived, swelling from just over 100 breeders in the early nineties to some 1,300 today. Breeders like to say they’ve democratized trophy hunting, providing even small outfitters with monster bucks befitting the King Ranch. That’s been a boon not only for the deer business but for a way of life that’s central to the state’s identity; the industry has kept land in the hands of families who might otherwise have sold out to developers.

But in recent years this progress has come with a price. Since 2002, the industry has been bedeviled by a fatal pathogen that’s endemic in parts of Colorado, Wisconsin, Wyoming, Nebraska, Utah, and New Mexico. Chronic wasting disease (CWD), as it’s known, isn’t caused by a virus, bacteria, or parasite but by an abnormal protein called a prion that can destroy a deer’s brain and spinal cord. Deer contract it by interacting with infected animals or coming into contact with their saliva, urine, or feces. They can even pick it up from contaminated soil. It’s the cervid equivalent of mad cow disease, scrapie in sheep, or Creutzfeldt-Jakob disease in humans. It transforms once majestic animals into staggering husks that die well before their time. “You don’t want this out in the Texas Hill Country, we’ll put it that way,” says Bryan Richards, a CWD expert at the National Wildlife Health Center.

For years Texas represented a disease-free island of millions of whitetail deer. To keep things that way, in 2002 the Texas Parks and Wildlife Department began testing some roadkill and hunters’ kills. The heads of dead deer were sent to the Texas A&M Veterinary Medical Diagnostic Laboratory, where technicians would remove part of the brain stem and the lymph nodes and search for the telltale spongelike appearance of infected tissues. Though every deer tested came up negative, in 2005 the TPWD got more aggressive, closing the border to the importation of deer.

But those rules didn’t stop wild herds of infected mule deer from crossing over from New Mexico three years ago. Alarmed wildlife officials responded by designating containment zones in El Paso and Hudspeth counties and putting checkpoints and a more stringent testing regimen in place there. For three years, the line seemed to hold. Not a single free-range or captive Texas deer tested positive for CWD. The question was how long it would last. “Texas has historically been very liberal with regard to what it allows landowners and deer breeders to do,” says Richards. “When you throw a little bit of infectious material in the mix, bad things can happen.”

Terrie Moss, a retired teacher, inherited these two hundred acres north of the Trinity River from her parents in 2011. It took her and Steve two years to grub the mesquite thickets, scrape the cactus, and erect a perimeter fence and the paddock fencing that grids this rocky country. Once they had finished, they sold their house in Sunset, hauled a mobile home to a spot near some tall oaks, and put everything they had into a high-overhead enterprise. “We’re not doing it to get rich is all I can say,” Terrie jokes. Today they have six hundred head that they tend daily, with the help of their son, Brazier.

They also send in the brain stem of every deer that dies on their property for testing, as required by the Texas Animal Health Commission’s CWD monitored-herd program, which offers the cervid industry’s equivalent of the Good Housekeeping Seal of Approval. The Mosses voluntarily entered the program six years ago; they were, by all accounts, doing everything by the book.

Then, this past June, a deer that died of a broken neck at Texas Mountain Ranch, in Medina County, tested positive for CWD. When TPWD tested an additional 42 deer from Texas Mountain that were considered high risk, it found 3 more cases.

Given that Texas Mountain is among the state’s biggest breeder-outfitter hybrids, TPWD launched a full-scale investigation. “There are over eight hundred animals associated with Texas Mountain Ranch, and we know well over three hundred were [sold], so they’re out there,” says Clayton Wolf, TPWD’s wildlife division director. In September, another CWD-positive deer originating from Texas Mountain was found at a facility in Lavaca County.

The Mosses had bought a deer from Texas Mountain in 2012, so Terrie knew she would be hearing from the commission. Her letter arrived in mid-July. The commission referred to the animal by its unique number, but Terrie had always called her Alice. The letter informed the Mosses that to continue selling deer they would have to euthanize Alice and have her tested. There is currently no USDA-approved live-animal test.

“I cried for a week,” Terrie says. She felt sure that Alice wasn’t sick and procrastinated as long as she could before arranging for a veterinarian to put her down. “They had to cut her head off and pull the brain stem,” she recalls. If the test came back positive, the Mosses would have to exterminate every deer they owned, which would mean the end of their livelihood.

Two weeks later, as Terrie expected, the commission informed her that Alice was disease-free. “There wasn’t any doubt in our minds that she was okay,” she says. “It was just a senseless death.”

Chronic wasting disease might as well have been purpose-built to ignite old animosities between TPWD and deer breeders. The industry has always loathed a provision of Texas statute that classifies all whitetail deer as wildlife and thus a public trust. Technically, a breeder doesn’t own deer, though in practice they can sell them for a tidy sum.

TPWD’s supporters in this fight—conservationists, wildlife managers, and traditional outfitters who disdain the intense focus on antler size—say the breeders’ commodification of wildlife and fixation on the antler arms race has warped Texas’s hunting culture. Breeders claim that the crackdown stems from the rack envy of wild-game ranches. CWD, they allege, is the perfect pretext for making their lives miserable. “Parks and Wildlife is picking winners and losers,” says Texas Deer Association director Patrick Tarlton.

Breeders have long known that CWD would eventually find its way here. And it didn’t take long for word to circulate that the disease had been detected at Texas Mountain; almost immediately, TPWD’s deer-transfer permit system saw a spike in activity as South Texas breeders raced to get ahead of the coming regulatory freeze. In an unprecedented step to halt the movement of potentially infected animals, TPWD deactivated the system for two months.

When business resumed in late summer, it was under a new regime of emergency rules. Breeders like the Mosses, who can show negative tests for deer purchased from Texas Mountain, have seen their hold orders lifted. If for whatever reason breeders can’t demonstrate this—because, say, an animal died earlier—they will fall to the bottom rung of a newly created caste system of potential disease risk. To shake off the designation, they have to meet a number of stringent requirements, such as proving that they have tested a certain percentage of their animals. In most cases, that necessitates the sacrifice of healthy deer, each worth hundreds if not thousands of dollars. Add to that the cost of testing, which can run $150 per animal, and getting right with TPWD becomes an expensive proposition.

Talk to any breeder and it becomes clear that they and the regulators exist in separate factual galaxies. The breeders don’t even agree that CWD is a major threat. “This is a political disease,” Steve says. Terrie notes that of the legions of deer tested, only a handful have come up positive.

“We do not feel like it’s contained, because we don’t know where it came from,” counters TPWD’s Wolf. All that investigators know about the infected deer at Texas Mountain is that they were artificially inseminated on the same night by the same vet. But they haven’t determined if that event was the source of the disease. In September the state forced Texas Mountain to kill 173 more deer—the remainder of its penned whitetail population. None of them tested positive. Now the state has told the ranch’s owner, Robert E. Patterson, to kill the rest of the deer in his pastures. Patterson says he has already suffered $3.2 million in inventory losses.

At a TPWD meeting in Austin in November, breeders came from all over the state to protest the proposed extension of the emergency rules into next summer. Dozens of men in boots and hats embossed with the names of their ranches milled about the halls of TPWD’s bunker-like concrete building, grousing about anemic sales. “I’ve moved six deer,” Niederwald breeder Bobby Schmidt said of his business since the emergency rules went into effect. “That’s normally one hundred and fifty deer.”

So many had shown up for the meeting, in fact, that TPWD set aside a second room just to accommodate the overflow. But when the hearing began, everyone crowded into the small, wood-paneled council chambers, some clutching pieces of paper scrawled with the grievances they planned to air. After waiting through some early agenda items, the breeders began filing to the lectern. Parks and Wildlife, they lamented, had effectively slapped a scarlet letter of disease onto many ranchers who had done nothing wrong.  “I feel like I’m being discriminated against,” said Van Bruns, a breeder and outfitter from Live Oak County.

David Yeates, the CEO of the San Antonio–based conservation group Texas Wildlife Association, saw it very differently. “We haven’t found the source,” he said. “This is an opportunity to nip this in the bud and react in a responsible manner.” After about an hour of testimony, no one was particularly shocked when the commission ratified the rules.

For now, at least, breeders have no choice but to settle in under the new normal while TPWD investigators hunt for a Patient Zero they may never find. “Everything has changed. When it changes, you conform to it and go on,” Terrie says. “What choice do we have? We’ve invested everything in this.”