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During their Sept. 15 meeting, the Wyoming Livestock Board (WLSB) passed changes to their Chapter Two rules related to brucellosis testing. The new rules changes the age requirement for all heifers for testing from 18 months of age to 12 months of age.

“We really want producers to understand and know about these changes, so they’ll be ready to comply with them after the first of the year,” said Wyoming State Veterinarian Jim Logan.

The rules were signed into effect by Gov. Matt Mead on Oct. 31 and went into effect on Jan. 1.

Rule clarification

The new Chapter Two rules state that all sexually intact female cattle and bison 12 months of age and over must have a negative brucellosis test within 30 days prior to moving or changing ownership between the dates of Feb. 1 and July 31. From Aug. 1 to Jan. 31, any negative test is valid until the end of the time period.

The rules further clarify the age for testing stating, “Heifers born during the previous calendar year and shipped after Aug. 1 of their yearling year shall be tested for brucellosis.”

Logan says, “The key change is the definition of test-eligible bovinae, which is cattle and bison.”

“The previous definition of test-eligible females were those 18 months of age and over,” he explains. “It also previously included visibly pregnant or post-parturient bovinae. Now, it simply says all sexually intact female cattle 12 months of age and over.”

Impetus for change

The rules were amended following the discovery of brucellosis last fall in a herd in Sublette County.

“We recognized that the old rule did not adequately cover heifers that may have been exposed to a bull during the breeding season and yet might be sold as feeders while less than 18 months of age that could have been a brucellosis transmission risk,” Logan says. “During the epidemiologic investigation of the case in Sublette County, a potential loophole in the rule was identified, so the Board voted to change the rule to include testing any heifer or sexually intact female 12 months of age and over.” 

Taking comments

The rules were out for comment during the summer, and Logan noted that both brand inspectors and producers mentioned that requiring brucellosis tests for yearling heifers was vague, especially when looking at a group of heifers in June or July, wondering whether they are 12 months of age or not.

“The Board decided to include in the section about test requirements that heifers shipped after Aug. 1 of their yearling year shall be tested prior to movement from the DSA or change of ownership,” Logan explains.

Additionally, the validity of the test varies based on date of movement.

“Any brucellosis test between Aug. 1 and Jan. 31 is valid until Jan. 31. From Feb. 1 to July 31, tests have to be done within 30 days for movement or change of ownership,” Logan says, noting that the change of dates relates to the risk of exposure during the elk or bison abortion or calving season.

Impacts

Logan notes that he does not believe the new test requirements will affect a greater number of producers that were not testing for brucellosis before. However, he believes more cattle will be encompassed in the increased test requirements.

“This change will encompass quite a few more cattle than what were tested before,” he explains. “That leaves me with a little bit of concern about how much more this costs the budget.”

Logan notes that, despite increased costs, the rule change should help to prevent potential brucellosis spread.

Veterinarians who test cattle are compensated five dollars per head, which could impact budgets. Additionally, veterinarians at sale barns are paid, and the sale barn is compensated if they provide the crew to help work cattle.

“Our expenses will probably be slightly higher, but these changes should help to prevent a wreck from occurring,” Logan comments.

Saige Albert, managing editor of the Wyoming Livestock Roundup, and Emilee Gibb, editor, contributed to this article. Send comments to This email address is being protected from spambots. You need JavaScript enabled to view it..

Pinedale – Wyoming’s Brucellosis Coordination Team (BCT) discussed a number of possible means to reduce the disease’s transmission between elk and cattle at its April 13 meeting in Pinedale.

Research projects, affected herd updates, budget crunches and new data were shared by Wyoming, Montana and Idaho agencies, and the daylong meeting closed with a call for the BCT to move forward.

Studies and updates

Montana State Vet Eric Liske presented study updates, as did its wildlife agency, and Wyoming Game and Fish Department (WGFD) biologists presented data from elk hunters’ surveillance and GPS studies in Wyoming.

A research project led by University of Wyoming’s Noah Hull brought exciting news that a test is getting closer to being able to distinguish former vaccine Strain 19 titers from the actual disease.

Strain 19 was found to be very effective for cattle but also produced “false positives” in blood tests, so it was dropped. Finding a reliable vaccine and improved tests are high on the list of accomplishments the BCT encouraged.

BMAPs

A top recommendation from the Governor’s Brucellosis Coordination Team was for WGFD to update its brucellosis management action plans (BMAPs), according to WGFD Brucellosis Program Supervisor Brandon Scurlock, who released the top 10 at a public meeting March 24 in Pinedale.

“We met with producers and partners in late December and asked how to better reduce transmission from elk to cattle and elk to elk,” he said.

Those comments were integrated into the BMAPs that Scurlock presented at the BCT’s April 13 meeting in Pinedale.

The 10 elements are feedground locations, elk population reduction, feedground phase-out, reducing feed season length, habitat enhancement, fencing, acquisitions and easements, test and slaughter, vaccine investigation and mapping areas of brucellosis risk.

Options

Infected cow elk miscarriages or abortions peak in March, April and May, which overlaps with concentrated elk feeding to keep elk from mixing with livestock. At several feedgrounds, seasons are shortened and hay is scattered for low-density feeding. Another tool is allowing scavengers to clean up the feedgrounds.

Elk are traditionally fed on one or two long lines that create hotspots for brucellosis transmission, he said. Fed farther apart in a checkerboard pattern, studies show elk contact with fetuses can drop by 75 percent. However, some sites are not suited for change.

Moving feedgrounds could influence behavioral changes and reduce transmission risks. However, brucellosis would still persist.

Feedground phase-out could increase elk-to-cattle brucellosis transmission in the long run, he said. Starting to feed late or ending early might reduce transmission, be fairly cost-effective and keep elk population objectives, or it might increase commingling during prime transmission.

Assessments

The Dell Creek and McNeel feedgrounds near Bondurant aren’t managed for end dates due to adjacent livestock herds.

Habitat enhancement could reduce seroprevalence where elk have access to more forage. Land acquisition, easements and fencing secure habitat and reduce commingling but are expensive and rely on landowners’ cooperation.

Test and slaughter, used from 2006 to 2010 to slaughter elk testing seropositive for brucellosis, worked until several years after it ended, but then seroprevalence spiked again.

New vaccines, vaccine delivery, better field tests and contraceptives are always under study.

The BMAP’s final action suggests mapping brucellosis risk. The BCT asked WGFD to update feedground herds’ seasonal ranges and GPS data showing biologists where elk are during major brucellosis transmission season could be used to make risk maps.

Using tools

Bousman suggested different BMAP tools might reduce transmission risks at feedgrounds near cattle producers.

Sommers agreed, saying, “Everyone’s situation is different.”

After Scurlock shared draft BMAPs, the BCT board discussed them at length. He noted difficulties with phasing out feedgrounds and said this is the first winter WGFD did not vaccinate elk with Strain 19.

Scurlock’s data-driven map of GPS locations for elk in February through June and March through May could be used for “risk assessment maps” for land managers, producers and agencies. The draft will be finalized by the BCT’s November meeting.

“I fully believe we need to look at risk assessment,” Sommers said. “If we look at feedgrounds, a handful are probably higher risk than others.”

Feedground activity

BCT member Terry Pollard stated, many feel closing elk feedgrounds would have “devastating effects on a lot of people.”

“What about moving feedgrounds away from the high-risk areas?” Price asked.

Sommers suggested perhaps one feedground could be moved and another could be used for test-and-slaughter.

“We need to prioritize the feedgrounds, do a risk assessment on each one,” he said. “If we ever really want to move the needle on this, rather than just having meetings every six months, we’re going to have to do some really hard work, get in there, and see if there’s any project we can use to reduce high risks…and then look at the options.”

“I think we need to keep our eye on different tools,” said University of Wyoming College of Agriculture and Natural Resources Dean Frank Galey. “Concentrating on risk assessment would probably be worthwhile. Otherwise, like Albert said, we’re just spinning our wheels.”

Jessica Crowder, representing Gov. Matt Mead, agreed with the need for the BCT to get more involved in reducing transmission risks.

“I want to say I appreciate this discussion about moving the needle,” she said, “and I think that will be appreciated by the Governor as well.”

Joy Ufford is a correspondent for the Wyoming Livestock Roundup and editor of the Sublette Examiner. Send comments on this article to This email address is being protected from spambots. You need JavaScript enabled to view it..

Jackson – As an economist, Dannele Peck guides her brucellosis research by asking how economically acceptable the prevalence of the disease is in a given area. The goal, she maintains, is to determine which combination of management tools will achieve and maintain an optimal level as cheaply as possible.

“To do that, we have to figure out how costly the disease is, how costly the potential management tools are and how effective they are,” stated Peck, a University of Wyoming associate professor in the Department of Agriculture and Applied Economics, at the Sept. 16 meeting of a National Academy of Sciences committee reviewing brucellosis in the Greater Yellowstone Area (GYA).

Peck added that disease managers should also consider whether efforts are focused on elk or cattle and what factors may affect the spread of the disease.

“How costly is a case of brucellosis in a cattle herd?” she asked. “As a good economist, I will say that it depends.”

The size of the herd, the number of affected animals, the need for depopulation versus quarantine and the timeline for quarantine are all factors that can affect the cost of an outbreak.

Evaluating an outbreak

Using some averages and assumptions, Peck and her team estimated that a brucellosis outbreak would cost approximately $192 per head over a 12-month period.

“We have to understand how costly our management activities are,” she continued. “We don’t want to spend $15,000 to solve a $14,000 problem.”

To evaluate various management techniques, Peck and her team of graduate students determined the annualized costs of certain tools and compared them to the financial loss of a brucellosis outbreak.

Citing an example data set for a high-risk herd, Peck commented, “Something like an adult booster vaccination is cheap enough that it doesn’t have to very effective to be worthwhile. It only needs to eliminate five percent of the cost of an outbreak to pay for itself.”

In the same example, delayed grazing would have to be so effective that it eliminated an impossible 104 percent of the brucellosis cost.

Therefore, she concluded that a vaccination may be a potential solution, but delayed grazing would not be economically beneficial in that situation.

Value of tools

“When we have lower risk and there is less at stake, we are not going to be willing to invest as much in brucellosis management,” Peck continued.

Fencing haystacks, asking the Wyoming Game and Fish Department to haze elk and using adult booster vaccinations may still have some value in high-risk herds, while spaying heifers, using alternative feed schedules and hiring a rider to haze elk may become less economically viable when risk is reduced.

To compare finances for investing in particular tools, Peck remarked, “We could put that money away each year so by the time an outbreak hits, we have saved up the difference.”

Along with more typical management tools, Peck’s team also investigated fencing winter feedgrounds and running stocker operations.

Due to high labor costs, Peck stated, “Elk-proof fencing costs $95,000 to $100,000 per mile.”

Fencing also raises other concerns about neighboring operations and important wildlife migration routes.

Stocker operations

“What if we got rid of reproductive cattle in the GYA?” questioned Peck.

Her team revealed that stockers are generally 50 percent less profitable than cow/calf/yearling operations.

“We would be asking producers to trade their brucellosis risk problem for what is probably a much larger financial risk problem. Producers are managing many other sources of risk,” she said.

The cost of a brucellosis outbreak and the costs of management tools vary by ranch, by year and by prices.

“It’s a very individualized situation. If we know the characteristics of a ranch, we can help narrow down the list of tools that might be economically worthwhile,” she remarked.

Researchers are learning more about how brucellosis is spread and what management tools may be effective, but Peck emphasizes the financial constraints of producers.

“We can’t forget our major economic questions,” she said.

Natasha Wheeler is editor of the Wyoming Livestock Roundup and can be contacted at This email address is being protected from spambots. You need JavaScript enabled to view it..

Washington, D.C. – In February 1996, USDA’s Animal and Plant Health Inspection Service (APHIS) licensed the Brucella abortus strain RB51 vaccine for use in cattle to reduce the prevalence of brucellosis, eventually replacing the use of the Brucella abortus strain 19 vaccine in the United States.

“Strain 19 is not a bad vaccine. It gave very good protection, but it produces antibodies that screw up the virology and, long-term, makes it very hard to eradicate the disease,” noted Gerhardt Schurig.

Shurig, an immunology professor in the Department of Biomedical Sciences and Pathobiology at Virginia-Maryland College of Veterinary Medicine, presented some of the challenges of developing the RB51 vaccine on Nov. 11 in Washington, D.C. at the Revisiting Brucellosis in the Greater Yellowstone Area meeting, hosted by the National Academy of Sciences.

Different strains

“When I started the research, I wanted to find out what characteristics would make a better vaccine,” he explained.

There are two basic morphological forms of Brucella bacteria, a smooth form and a rough form. Strain 19 is composed of a smooth strain, which creates challenges related to antibody production and diagnostic testing for brucellosis.

“This point is important because we immediately began to think about using rough organisms, but how to select those rough organisms is where things became complicated,” he said.

The strain that is chosen must be attenuated, or weakened, so that it can be potentially administered to animals of any age.

“We don’t want to expose people to a disease if they are using a vaccine, and we certainly don’t want animals spreading the disease,” Schruig noted.

The Brucella strain also has to be stable and suitable for booster vaccines.

“It needs to be inexpensive and easy to administer as well,” he added.

Research

In 1979, Schurig and his team began developing tools to select for desired Brucella strains, and in 1982, they presented positive findings for a potential vaccine at a conference in Baton Rouge, La.

“From 1980 to 1996, there were basically 16 years between having the strain and applying it. It takes a long time to have something approved,” he commented.

Now, scientists are trying to improve the efficacy of the vaccine by modifying how antigen qualities are expressed by the RB51 Brucella strain.

“There are many antigens that have been described as having protective qualities against Brucella, but are they the correct ones to use in a particular species? I think that is a very important question,” Schruig said.

Ongoing exploration

In mice, scientists are seeing positive results, but cattle or bison may exhibit different responses to the same vaccine.

“We have to run those experiments, and that is where we get into trouble. It is now so expensive, and the regulatory things are so complicated, one kind of throws their arms up,” Schruig remarked.

Scientists are also interested in how RB51 impacts tuberculosis (TB). Along with modifying for increased protection against Brucella, Schruig and his team are hoping to create a strain that protects against TB as well.

“I think the concept is really valid,” he stated. “We believe we have the strain to protect against both, and now we have to test it.”

Natasha Wheeler is editor of the Wyoming Livestock Roundup and can be contacted at This email address is being protected from spambots. You need JavaScript enabled to view it..

Riverton – Northwest Wyoming’s wildlife reservoir of brucellosis continues to create problems for cattle producers, and Wyoming State Veterinarian Jim Logan explained to producers at Fremont County Farm and Ranch Days that two new cases were seen in the state in late 2015. 

Currently, Wyoming has two cattle herds that are quarantined due to brucellosis.

“Montana only has one bison herd under quarantine, and Idaho doesn’t have any currently,” Logan said. “In Wyoming, we were able to release a bison herd in Park County that had been under quarantine since 2010.”

Cases of brucellosis

With cases of brucellosis occurring in 1988, 2003, 2004, 2008, 2010 and 2011, Logan noted that 2015 also showed two new cases of brucellosis.

Shortly after a domestic bison herd was released from quarantine, an infected beef cow was found in a Park County herd. The herd was quarantined. Testing showed that only one cow in the herd was infected. The cow was removed, and the herd has successfully completed two negative, whole-herd tests.

Less than a week after the Park County herd was quarantined, a veterinarian at one of Wyoming’s livestock markets found a suspect positive cow.

“The suspect positive was not Brucella abortus,” Logan said. “Confirmatory testing showed that another bacterial infection tripped the test and skewed results.”

“Three days later, another suspect cow was found in Sublette County,” he continued. “There were five cows in a group of cull cows that were positive, and additional testing showed six more positive animals.”

One negative, whole-herd test has been conducted to this point, and Logan added that no additional cows were found from herds that had commingled or had fenceline contact with infected herds.

“We are going to see this disease crop up from time to time in cattle in the Greater Yellowstone Area,” Logan said, noting that the wildlife reservoir means that total eradication will be difficult.

Brucellosis impacts

“Brucellosis is a bacterial disease caused by Brucella abortus,” Logan explained. “It was recognized as a big problem in this country in the early 1900s, and it is still a problem in the Greater Yellowstone Area.”

Brucella bacteria are shed from infected animals at the time of birthing, and bacteria are transmitted orally or by inhalation.

“Any animal that licks or sniffs the fluids, placenta or an aborted fetus can become infected with Brucella,” he said, noting that, if a live calf is born to an infected animal, that calf can also carry the bacteria. “Brucellosis is a chronic disease. Once an animal is infected with Brucella, it is considered to be a lifelong carrier of the bacteria.”

Logan explained that many producers are aware that brucellosis causes abortions, but it is also possible to see live calves born to infected animals.

“Typically, if an infected calf reaches full-term, it is alive at birth, but it probably won’t survive more than a few days,” he said. “The bacteria affects the lungs in the baby, so it dies after showing signs of pneumonia. Ranchers treat with antibiotics, and the calf dies showing signs of pneumonia.”

Because the ranchers don’t suspect brucellosis, they often don’t call the vet, and brucellosis is able to persist in the herd.

Preventing brucellosis

As a result of the wildlife reservoir in the Greater Yellowstone Area, Logan said that temporal and spatial separation are key to reducing impacts from the disease.

“Temporal separation means to keep cattle separated from wildlife at the time that brucellosis could be transmitted,” he explained. “The key period we are worried about brucellosis transmission in February through June.”

In February, March and April, wildlife infected with brucellosis are likely to abort their calves. Those who deliver full-term calves are expected to deliver in May and June.

While focusing on the key timing, Logan also noted that keeping cattle as far away from the wildlife reservoir as possible spatially is also important.

“It is difficult to keep cattle away from wildlife sometimes,” he said, “especially when people depend on public lands for at least seasonal grazing.”

“The good thing is that summer, fall and early winter are not considered significant times for risk of exposure,” Logan noted.

Surveillance

Logan also noted that surveillance and management are vital to preventing the disease in cattle.

“Surveillance and management includes brucellosis testing,” he said. “I’m not suggesting that people everywhere in the state need to test for brucellosis, but within the boundaries of the Designated Surveillance Area (DSA), it is important.”

He continued, “At this point, we are not aware of a big risk factor in wildlife outside of the DSA, with the exception of Big Horn and Sheridan counties where we know there are infected elk.”

The Wyoming Livestock Board has designated Big Horn and Sheridan counties as an “Area of Brucellosis Concern,” and therefore surveillance testing there is important but is currently voluntary, Logan added.

Though Big Horn and Sheridan counties are not included in the boundaries of the DSA, seven hunter-killed elk were found to be positive for brucellosis during the 2012-14 hunting seasons. 2015’s hunting season did not find any new positives.

“We can also vaccinate for brucellosis,” Logan said. “Vaccination for brucellosis is mandatory in Wyoming for all heifers that are going to be kept for breeding purposes.”

Logan added that vaccination, however, is not 100 percent effective, though it is helpful in mitigating risk.

“Every herd, with the exception of the first one in 1988, has been 100 percent vaccinated for brucellosis,” he said. “Vaccination is another tool, and it reduces the chance of infection and abortion. It is not 100 percent. We have to combine vaccination with appropriate management to be effective.”

Saige Albert is managing editor of the Wyoming Livestock Roundup and can be reached at This email address is being protected from spambots. You need JavaScript enabled to view it..