Livestock Biosecurity Upgrades

Now is the time for dairy producers to upgrade their biosecurity measures as Highly Pathogenic Avian Influenza (HPAI) H5N1 virus spreads across the United States.

Currently, more than 900 cases of Highly Pathogenic Avian Influenza (HPAI) H5N1 virus are confirmed in U.S. cattle. As the disease spreads, now is the time for dairy producers to strengthen their biosecurity practices to help prevent infection.

Biosecurity protocols are nothing new for dairy producers, but most measures were designed for slower-moving pathogens. That’s not the case for HPAI, said Linda Tikofsky, DVM, Boehringer Ingelheim.

“Our old biosecurity practices used to fit the bill, but all of the sudden we have something virulent and fast moving that’s affecting large operations all at once,” Tikofsky said. “This is our practice session for a foreign animal disease outbreak like foot-and-mouth disease (FMD).”

Continue biosecurity benchmarks

Tikofsky noted most dairy producers are already practicing solid biosecurity measures such as: disease testing before new animals enter the herd; ensuring vaccinations are up to date; requiring employees to wear protective clothing; installing boot wash stations; and using separate equipment for manure and feed.

Continuing these practices will help herds prevent diseases like contagious mastitis and Johne’s. However, it’s probably not going to be enough to stop HPAI.

Enhance biosecurity

To help reduce the risk of HPAI, producers should be more stringent about new animal introduction and comingling across herds. Isolating new animals for two to three weeks will help ensure cattle are disease free, Tikofsky advised.

Next, producers should crack down on visitor access to animal areas. This is an area where manufacturer partners should actively participate.

“Now, when I visit a farm, maybe I’ll meet in the office but not in the animal areas,” she said. “Plus, we’re wearing disposable boots and don’t go uninvited to other areas of the farm. That’s a good thing that producers should be requesting of their suppliers.”

Producers also should understand risks from regular employee movements. For example, workers with backyard chickens or who go home to their own cattle
herds may be risking the biosecurity of the farm. Establishing dedicated boots and coveralls can help reduce cross contamination. Employees should be provided with additional protective clothing like gloves and protective eyewear for their own protection as HPAI in humans can cause conjunctivitis.

Most commercial sanitizers are effective against HPAI, but increased frequency of cleaning and sanitization is a best practice for higher risk areas.

“I also recommend thinking about fence line contact for pastured cattle. Know who is in the pasture next to yours and make sure there is a sufficient buffer zone between fence lines,” Tikofsky recommended. “I also recommend people have their own trailer and don’t lend it out or borrow from anyone else. Wash it out and sanitize even when used between the same age groups or operations. Trailers can act as a fomite as well.”

Early surveillance and detection

Early signs of HPAI can show through wildlife or domestic cats, Tikofsky said.

“In affected herds, the first kind of ‘ah-ha’ moments were signs like unusual bird die-offs or cats that were sick. I advise producers to look for these warning signs that are out of the ordinary.”

If producers notice these signs, report them to your herd veterinarian. In the event HPAI is detected on an operation, the first step would be to stop all animal movement in and out of the herd.

Supportive protocols for affected animals may include fever-reducing medication and fluid therapy. Because of the high transmission of viral particles in raw milk, pasteurized milk and heat-treated colostrum should be fed to youngstock to limit the spread within the herd.

“What we’re learning is that HPAI on a particular operation may run its course in three to four weeks,” she said. “There’s still a lot of unknowns. We don’t know if these affected animals will be immune for life or susceptible in the future. Your herd veterinarian can help you design protocols to support the herd. Plus, multiple companies are working to make a vaccine. We all understand the severity of this disease.”

Biosecurity tips for distributor sales representatives

• Make an appointment before visiting a dairy.
• Select a meeting place away from animal areas.
• Immediately put on disposable boots.
• Do not go uninvited to other areas of the farm.

Photo caption: Linda Tikofsky, DVM

Photo credits: istockphoto.com/SeventyFour