Wisconsin just confirmed its first fall case of highly pathogenic avian influenza (HPAI) at a turkey farm near Rice Lake. With the fall bird migration underway, state officials urge farmers to immediately tighten their biosecurity procedures.
Cool weather and migrating flocks significantly increase the HPAI risk for domestic birds. Dr. Keith Poulsen of the Wisconsin Veterinary Diagnostic Laboratory spoke to the Mid-West Farm Report about the state’s new case.
“Hopefully, with the harvest going on time or maybe even a little bit early when it’s dry, and especially where it’s dry up north, hopefully, those birds will move through and move through quickly. We know that we have multiple different strains that are circulating in our migratory waterfowl, and unfortunately, Wisconsin has seen our first case. It happens to be in an area that’s pretty dense for poultry producers, so we’re working with our poultry clients and the Department of Animal Health to make sure that we have our surveillance and testing for permitted movement, and then working through the depopulation, cleaning and sanitation on the affected premises.”
Poulsen notes a single strain of HPAI frequently infects chickens, turkeys, and even lactating dairy cattle.
“Our highly pathogenic influenza strains cause mortality and morbidity, depending on the species, and the H5N1 has been the predominant strain for at least the past five years. Sometimes we see different H numbers and N numbers, and that’s really for the epidemiologists, but it’s been our H5N1s and further sub-types down the line as influenza viruses change all of the time.”
What About Cattle?
Officials are also monitoring the state’s cattle supply. Texas and other western states continue to report H5N1 “B” strain cases in lactating cows. This directly impacts Wisconsin farmers, who often send young calves to Texas to grow before returning them to the milking herd.
“It’s a really favorable climate to grow heifers and breed heifers, and you know, Wisconsin moves about six thousand. That’s an old number, and it might be more than that now of baby calves (sent to Texas) then coming back as bred heifers. Then, we have shows like World Dairy Expo coming up next week, but because we’re not moving lactating animals into the state at high risk, we really haven’t seen this B-as-in-boy strain. With Texas and Idaho, California, and Utah right now. That “B” strain is still circulating because we’re continuing to move lactating animals as part of that dairy production model, and unfortunately, we’ve had some endemic spread. Just in Idaho this summer, we saw a bloom of cases on new premises.”
No Change In Cattle Testing Requirements
Despite the western H5N1 cases, Wisconsin has not changed its animal movement guidelines. Exhibitors attending the World Dairy Expo face no new or additional steps.
“It’s just usually over one thousand lactating animals, but we tend to see between 25-hundred and three thousand total animals at World Dairy Expo. Of those lactating animals, about a third of them are from Wisconsin. Then the rest, because it’s a world show, are from Canada and the rest of the contiguous 48 states. Nothing has changed on testing requirements. Any animal originating from a state that’s not what we call gold status or disease-free status, they require milk testing for lactating animals within seven days of arriving at the World Dairy Expo grounds.”
