Deadly Disease Outbreak in Breeder Deer Threaten Texas’ 3.9 Million Whitetails

State wildlife dept’s approach to containing Chronic Wasting Disease inadequate, say conservationists.

STAFF AT THE Texas Parks and Wildlife Department (TPWD) haven’t gotten much sleep since March. The worst nightmare a wildlife agency in a deer-rich region like Texas with its 3.9 million wild whitetail deer and 85,000 captive breeder deer could possibly imagine now ranges the landscape: Chronic Wasting Disease.

Since late March, the department has found evidence of 30 cases of the disease, with no known cure, in six deer-breeding facilities in the state, raising fears that it could spread at game ranches and even among wild deer populations.

Texas is the only state in the US that allows breeders to sell deer to shooting preserves that already contain wild deer, which makes the likelihood of cross-contamination high. Photo by M&R Glasgow / Flickr.

Chronic Wasting Disease (CWD) is a type of transmissible spongiform encephalopathy disease (TSE), an always fatal, progressive, neurodegenerative disorder. TSEs include scrapie in sheep and “mad-cow disease” in cattle. The latter can be transmitted to humans, causing Creutzfeldt-Jakob Disease (CJD), a similar, rapidly spreading, fatal neurodegenerative disorder. Although to date, no CWD affected deer and other cervids have been found to cause a CJD in humans, the Center for Disease Control still advises hunters not to eat CWD-infected deer.

At first glance, 30 cases appear almost trivial, nothing to lose sleep over. But the nightmare begins to takes shape once you learn that CWD-infected deer can remain asymptomatic for roughly five years. Which means, in order to curb the spread of the disease, wildlife officials need to contact trace every breeder deer moved in and out of the eight CWD-positive facilities over the past five years. The department is now scrambling to compile a vast epidemiological “trace-out” network from the eight CWD-positive facilities. Once that is completed, TPWD will focus more on a second trace-out from the 103 “release sites” that received over 1,700 deer from these facilities for hunting over the past five years. Finding many of those deer might prove to be nearly impossible.

“That’s part of what’s keeping my staff up at night,” says TPWD Director John Silovsky.

Texas is the only state in the US that allows breeders to sell deer to shooting preserves that already contain wild deer, which makes the likelihood of cross-contamination high. Wildlife experts now fear that this could lead to a slow-moving, incredibly hard-to-contain pandemic in the farmed and wild deer populations in the US. Additionally, they are concerned that the TPWD’s test-based response to the outbreak isn’t quite adequate.

CHRONIC WASTING DISEASE infects both wild and captive-breeder deer across large parts of the United States. Since 2012, Texas has been on alert after a “free-ranging” or wild mule deer with CWD appeared in far west Texas. But the spring 2021 outbreak occurred among the state’s 950 captive whitetail deer facilities, where whitetails are bred via artificial insemination to produce massive antlers or “racks.” Fed nutrient-rich grains and supplements, and living in age-classed groups in 1 to 2 acre pens, breeder deer grow far larger than most Texas wild deer. Texas breeders trade the most genetically promising bucks and does among themselves, moving the deer in trailers hundreds of miles across the state. They sell the remainder, about 30,000 deer each year, to some 4,700 high-fenced “release sites,” which are basically canned hunting operations. Hunters can choose their “trophies” online and pay up $15,000 to “hunt” their target deer. The more “points” or inches of antler a trophy carries, the higher the price. Guides take the hunters to pastures where their chosen trophies conveniently graze at grain feeders and offer easy shots.


The faux-frontier world of manufactured deer and canned hunting in Texas.

Wildlife biologists, who fear CWD is a major threat to wild cervid populations, believe that deer that escape from these farms or have nose-to-nose interactions with wild deer through fencing or at hunting sites could be instrumental in its spread in the wild.

The abnormal proteins, called prions, that cause CWD spread between animals through body fluids like urine, feces, saliva, and blood. They spread not only through direct contact but also through contaminated soil, food, or water. Researchers think that feeders and mineral licks are potential contamination sites as the grounds surrounding feeders where deer eat grains in breeding facilities and in hunting ranches invariably becomes saturated with waste.

Although hunting release sites, like deer breeding farms, are required to be surrounded by six -foot fences, that’s considered to be only a “deer-resistant” barrier, not deer-proof. It’s not unusual for a whitetail deer to jump over a six-foot fence. Nor do high fences always remain intact.

February’s “Icemageddon,” which nearly destroyed the Texas electrical grid, brought down trees and tree limbs on many farms, and those in turn brought down deer fences. May and June saw a series of massive floods along Texas creeks and rivers that felled more trees and damaged more fences. The TPWD now calculates that roughly 10,000 deer escaped breeder facilities from 2015 to 2019.

“There’s a significant possibility that the free-ranging deer population has been exposed to CWD,” reads one recent TPWD document the Journal has access to.

IN LATE JUNE, the department announced that the eight original CWD positive facilities had sold several hundred deer (one unnamed source says about 450) over the past five years to 138 other deer breeding facilities. Those deer have apparently since been killed and tested for CWD. The test results take time, about a week at minimum. A CWD-positive test, called a “suspect” finding, is then sent to the US Department of Agriculture veterinary laboratory in Ames, Iowa.

The TPWD has not yet announced definitive test results. However, 66 of the 138 breeder farms were classified as “cleared,” meaning that either the tests results for deer transferred to these 66 farms deer from the 8 infected facilities came back negative, or the farm owner decided to kill all his deer and start over. In the remaining 72 breeding facilities, which together have some 9,700 deer, owners are either still waiting for post-mortem test results, or have already started live or “whole herd ante-mortem testing of the remaining deer,” according to department documents on the matter.

All deer among these 72 farms that have been exposed to a CWD-infected deer must be live-tested, most often through a sample of rectal tissue. Any of the farms that cannot locate all of the deer that came in from the eight CWD-positive facilities must live-test their entire herd, at first within the 45 days of an infection being detected and again two years later. However, live or ante-mortem CWD test often do not detect the disease in its early stages, that is before it shows up in brain tissue. Conducting a second test two years after possible exposure attempts to address antemortem test limitations.

Unfortunately, these 72 breeding facilities were allowed to sell their deer up until they received a “No Movement” order, meaning no sale of deer, from the Parks and Wildlife Department on June 22. In the five years prior to that date, these farms have sold an undisclosed number of breeder deer to another group of 214 deer breeding farms, which the department is calling “Tier One.” Tier One contains over 26,600 deer. Most, if not all of these animals will have to be subjected to whole-herd ante-mortem testing. It’s not yet known how many deer these Tier One farms have sold to other breeding facilities in the past five years and where those animals were sent. That list of facilities would make up Tier Two of the contact web.

Researchers think that feeders at hunting ranches like these are potential contamination sites as the grounds surrounding the feeders invariably become saturated with waste. Photo by M&R Glasgow / Flickr.

A buck killed at a canned hunting operation. The Texas wildlife department has issued emergency rules at all deer-breeding facilities and hunting operations to radically increase CWD testing. Photo by Becky Wright.

The department still needs to determine how many deer all of these facilities sent to canned hunting sites in the state. Finding many of those deer might prove to be nearly impossible, especially since farm-raised deer do not have any readily visible tag identifying them, only a tattooed number inside one ear.

Critics of the industry routinely try to get the Texas State Legislature to pass a bill mandating breeder deer wear an identifying tag. Roy Leslie, one of the leaders of a grassroots coalition of wildlife advocates and landowners says, when he last visited a state committee weighing this issue, a breeder got up and bluntly said, “Why would somebody want to shoot a deer with a yellow tag?” A big yellow tag would ruin the fantasy of shooting a wild trophy buck.

IN ADDITION TO THE no-movement order at the 72 facilities, the TPWD has issued 90-day emergency rules at all deer-breeding facilities and hunting operations to radically increase CWD testing. All dead deer will have to be tested within 14 days of death — a change from 2016 protocols allowing a breeder to keep tissue samples in a freezer and send the whole bunch off once a year. The 2016 rules required only modest sampling of live deer for CWD tests every year. Sample sizes for live testing of deer are now being increased in an effort to detect CWD infections in a herd earlier.

Also all deer from breeding facilities sold to release sites, an estimated 30,000 a year, must be tested. Breeders who don’t comply will have a “No Movement” order imposed, and may subsequently have their permit denied.

There is now talk among breeders that the department will soon require every deer sold by a breeder to another breeder to be tested before it can be moved, irrespective of whether or not CWD exposure has been traced to their facilities.

All told, breeders face new emergency rules calling for at least another 40,000 antemortem tests a year, and this testing must take place within strict time frames.

Many Texas deer breeders, who were already chafing under the preexisting CWD testing requirements that they felt unfairly targeted their industry, say these new rules are not going to be effective in curbing the disease and instead will further hurt their business.

A “shooter” buck sold to a hunting site, for instance, must be in the pasture ten days before hunting season begins. This year, the season begins on October 2. Although CWD test results on live deer by the official Texas Veterinary Medical Diagnosis Laboratory take some two weeks to get back in normal times, in a high-demand period it can take six weeks. Just getting the sample tissue from the deer to send to the lab is no easy matter.

Dr. Scott Bugai, a Seguin, Texas-based veterinarian, deer breeder, and member of the TPWD’s CWD Advisory Board, explained the process: “I’ve got a bunch of buck deer ready to be released. To live test a deer, we either go into the pen and shoot them with a dart gun — they get hot, they run into fences, get hurt — or we put them in chutes in the barn. They still get hot [and agitated].”

Bugai questioned the value of the new rules. “What we’re doing now is overkill. If a person had a Covid test twice a day, it’s better surveillance, but is it necessary? I think it’s burdensome and excessive. I’m working harder, every day, every week, every night. I don’t know if we can do this.”

Bugai also thought the deer breeders faced an unfair testing burden compared to testing wild deer shot by hunters. “We test our pen deer. It’s a 20 to 1 ratio of pen to wild deer testing already,” he says. “There should be parity.” Bugai believes the department should “look for [CWD] in the pasture at the same rate we look for it in the pens.”

Greg Simons, a hunting outfitter and past-president of the Texas Wildlife Association, also thought testing to be a “pinch- point” in the system. To take a sample tissue from a deer in antemortem testing requires a licensed veterinarian who is also accredited as a Level II large animal vet by the USDA, and is certified is by the Texas Animal Health Commission. In Texas, only 158 vets have that certification, which may not be enough to meet breeder demands given that it’s a part-time job and that testing requirements are radically escalating.

Wildlife conservation advocates agree with some of these concerns. “My God, why would somebody — the breeders — do all this stuff?” asked Leslie after he studied the new CWD test requirements. “I don’t see how they can physically do it, jumping through all these hoops.” But more broadly, they doubt that the risk-management paradigm being used by the TPWD can actually work with chronic wasting disease.

The agency thought it could manage CWD with what Matthew Wagner, a retired Deputy Director of the Wildlife Division in TPWD described as “x level of certainty” with “y level of testing.” When this model failed this year, the TPWD thought, in Wagner’s words, “Now, let’s see how we tighten up to increase certainty.”

That revised technical approach will fail, Wagner says, “because CWD is going to do what it is going to do despite our best efforts. Is it even stoppable now with a malformed protein? We don’t know what causes it in the first place. Until we understand how this disease moves in the environment, we shouldn’t be moving deer around.”

To take one example, the first deer breeding facility where the current CWD outbreak was detected had been completely closed to new deer moving in for over a year. So far, trace-out investigations have not led to a deer from some other breeder. So how did CWD enter the facility? On someone’s truck tires or cowboy boots? On a newly purchased grain feeder? In artificial insemination equipment?

The thing is, once in the soil, the prions that cause CWD remain in the soil and, as far as is known, can be a potential contagion indefinitely. “We could be living with CWD in the land long after the breeders are gone,” says Leslie. “It’s not going away if you kill all the deer. In five years, you won’t be testing. But that doesn’t mean CWD is gone from the land. It doesn’t work that way.”

Wagner agrees that the TPWD’s more intense testing protocols will not work. “We’re building something that is not sustainable as a technical solution or sustainable financially.” he argues. “The only solution is to prohibit the movement of deer, not just breeder deer, but wild deer, too and carcass movement.”

Wagner visualizes a growing darkness over rural Texas. “If you have a property where CWD infected deer live, that could become a dead zone several years down the road. But we live in the here and now and dead zones are in the future. It’s hard to get your head around. People are only thinking about CWD in small, local terms, not about its potential impact on a large geographic area.”

This number of deer-breeding facilities in Texas is 950, not 9,500 as mentioned in an earlier version of this article.

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