Texas A&M AgriLife Extension research is documenting why many standard poultry biosecurity practices are less effective than the industry assumes.
Morgan Farnell, Ph.D., avian microbiology and immunology professor, associate department head and Texas A&M AgriLife Extension Service program leader, has spent nearly two decades identifying where routine biosecurity measures break down and what producers can realistically do to improve them.
Disposable PPE: A false sense of security
The most visible biosecurity practice at farm entrances, disposable boot covers, may also be one of the least reliable. Farnell's research found that walking on gravel or concrete can quickly perforate boot covers.
"A lot of this, in my opinion, is just theater," Farnell said. "We do these things to feel better ourselves, and they do reduce risk, but disposable PPE just rips off your body if you're really doing work."
To measure the problem, his team double-bagged students' shoes beneath boot covers and quantified how much bacteria penetrated the barrier. The results supported what many farm veterinarians already suspect — disposables offer limited protection under real working conditions.
Farm-specific footwear as a more dependable alternative, Farnell said.
Contact time: The step everyone skips
Across multiple studies, the single most consistent biosecurity failure Farnell's team has documented is inadequate disinfectant contact time. Most products require five to ten minutes of dwell time to be effective.
"Even though we have these fancy spray rigs, we're probably wiping everything off the minute we get back on the road," he said. "And the tires are dirty to begin with."
Surface cleaning must precede disinfection for either step to work. "No amount of disinfectant in the world will disinfect a dirty boot with fecal matter in the treads," Farnell said. "Most products recommend a good 10 minutes, and that's just not happening out there."
To address the contact time problem in his own farm visits, Farnell uses a rechargeable fire extinguisher filled with a non-corrosive disinfectant and pressurized with an air compressor. The setup lets him thoroughly coat wheel wells and tires and wait the full recommended contact time.
He also recommends that operations invest in a solid surface — asphalt or concrete — at farm entrances to allow for proper rinsing and timed disinfection.
"I think it'd be a good idea to have some kind of solid surface at a farm entrance where you can rinse things down and disinfect them," he said. "Maybe take a phone call, check your emails while you're waiting on the disinfectant to work."
Putting the risk in perspective
Farnell is careful not to suggest that current biosecurity programs are without value. The industry, he said, does a genuinely good job of risk reduction. But he is equally clear that no biosecurity program eliminates risk entirely.
"I think the industry does a really good job," he said. "However, I don't think you'll ever reduce your risk to zero. I've heard of some primary breeders that have had problems and they have amazing biosecurity. If those folks — who are at the very best at what they do — can have a break, I don't know if you can always be 100% sure you can prevent something. But we can reduce our risk."
