Wyoming state veterinarian looks back on 2017’s animal health challenges
Casper – During a Wyoming Stock Growers Association (WSGA) Livestock Committee meeting report, Wyoming State Veterinarian Jim Logan provided a summary on livestock health issues in 2017, as well as an update on rules and regulations governing livestock activities in the state.
This year, the most significant rule changes came in Wyoming Livestock Board (WLSB) Chapter Eight importation rules for livestock.
“With these revisions, WLSB requires only one polymerase chain reaction (PCR) trichomoniasis test for importation,” Logan stated. “I think the Chapter Eight revisions will help the cattle industry without putting producers at undo risk for trichomoniasis.”
Before the revisions, livestock being imported to Wyoming needed either three negative culture, two negative PCR tests or one of each to come into the state.
Logan added in 2017, there were no reported cases of trichomoniasis in Wyoming. The last reported cases of trichomoniasis were in October and November 2016 in Niobrara and Converse counties, he noted.
“While there haven’t been any trichomoniasis cases in 2017, that doesn’t mean trichomoniasis is eradicated either,” Logan said. “Producers and veterinarians all need to be very vigilant and careful about trichomoniasis, but hopefully, some of the WLSB rules are helping.”
Logan mentioned issues with tuberculosis (TB) in Wyoming in 2017
“During 2017, South Dakota had a major issue with cattle TB,” Logan said. “There were numerous disease traces from South Dakota that came back to Wyoming, and one trace indicated a Wyoming cowherd could have been the origin.”
According to Logan, cattle from a Wyoming herd went into a South Dakota herd that was found positive, so the original Wyoming herd was tested. The results were negative. Then, all of the cattle from the effected South Dakota herd were tested, and any cattle directly exposed to the South Dakota herd were tested and sent to slaughter.
“Any cattle that commingled with the removed cattle were also tested, and luckily, no TB was found in Wyoming,” Logan stated.
For the horse industry, a case of equine piroplasmosis cropped up in 2017. The disease primarily affected the horse racing industry.
“Wyoming has one location in Uinta County under quarantine for equine piroplasmosis because there are still a few horses that haven’t tested negative post-treatment,” Logan reported. “Most horses in Wyoming are likely not at any risk for equine piroplasmosis, but it’s been a fascination epidemiologic adventure.”
One disease Logan was very relieved to report about was brucellosis, a major concern for cattle in the state because infected wildlife can transfer the disease to cattle.
“As far as WLSB knows, we don’t have any cases of brucellosis in Wyoming,” he reported.
Logan added there was one situation early in 2017 that was a carry over from a case in Sublette County from 2015.
“The affected cattle herd was able to achieve three consecutive negative tests for brucellosis by May 2017,” he noted. “In October 2017, WLSB received a report from a slaughter house where a sample was taken that one animal had tested as a high reactor to brucellosis.”
Logan said the case was not an issue because the slaughtered animal was a spayed heifer, which couldn’t have transmitted any Brucella bacteria.
“The spayed heifer was also from a group that consisted solely of spayed heifers and steers, all of which had gone to slaughter or were in a terminal feedlot with no contact to other cattle,” Logan explained.
“Basically, life went on as normal, but this case showed us brucellosis is still circulating in the wildlife population,” he added.
Also mentioned, in June 2017, the United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) reviewed Wyoming’s brucellosis program.
“WLSB hasn’t received a final report from APHIS, but the preliminary report and recommendations are fairly complimentary of our program,” Logan stated.
The preliminary report recommended WLSB do more to address the brucellosis situation with the wildlife in the Big Horn Mountains where elk have tested positive for brucellosis.
“We really don’t know how many elk are affected, but so far 15,000 to 16,000 cattle from the Big Horn Mountains and Sheridan have tested negative for brucellosis,” Logan stated.
Other health concerns
There were also four cases of West Nile virus reported in 2017, but he suspects there were numerous other cases that went unreported.
“West Nile virus is still out there, and the key thing to remember is West Nile can be transferred to humans by mosquitoes. We need to be aware it’s still around,” he added.
Lastly, Logan stated blue-green algae toxicity was an issue in Wyoming in 2017.
“Blue-green algae toxicity is caused by a bacteria that infects water ways, usually stagnant or slow moving water,” Logan noted. “There were several locations where the blue-green algae blooms were found, and there were two verified situations in Johnson and Natrona County where it was involved in cattle deaths.”
He stated blue-green algae is something to look out for because it can kill not only livestock but people and pets, as well.
“WLSB keeps a running total of all the diseases required to be reported in Wyoming and watches for disease trends to help people, veterinarians and producers be aware of possible animal health issues,” Logan concluded.
The 2017 WSGA Livestock Health and Production Committee held their meeting on Nov. 29, 2017 at the Wyoming Natural Resources Rendezvous in Casper.
Heather Loraas is assistant editor of the Wyoming Livestock Roundup and can be reached at firstname.lastname@example.org.