October 15, 2019

Mycoplasma elimination possible, but more difficult on farrow-to-finish sites


With the right program in place, eliminating mycoplasma pneumonia is possible on many hog farms. Farrow-to-finish sites are still the most difficult to clean up, however, reported Swine Vet Center’s Paul Yeske, DVM.

He has carried out multiple mycoplasma-elimination efforts on different types of hog farms with good success.

“The farms that are easiest [to eliminate mycoplasma] are the farms that are multi-site production, where we have a farrow-to-wean site…The herds that have all ages of pigs on site, that’s where the challenge is going to be,” he said.

Long-term herd closure

The best method for eliminating mycoplasma from a farrow-to-wean site requires herd closure to allow the animals to develop immunity and stop shedding. Research shows the disease’s causative organism, Mycoplasma hyopneumoniae, can be shed up to 240 days.

“We expose all the animals up front to make sure everybody’s exposed and immune, and then we wait 240 days,” Yeske explained. “At the end, we use some medication as a secondary step to make sure we’ve controlled everything before we bring the negative animals back in.”

The advantage of this elimination program is a short payback period of a few months, he added. A depopulation-repopulation elimination takes a couple of years to pay back the expense.

Farrow-to-finish options

Farms with all ages of pigs on one site require more time and expense to eliminate mycoplasma. A partial depopulation that empties the nursery and finishing stages for a short time is one solution, according to Yeske.

“I think there are ways we can do [elimination] on really any given farm,” he said. “It’s just finding creative ways to do it. And the depopulation-repopulation would certainly be an option.”

Complete elimination

Could mycoplasma be completely eliminated from US herds?

“I think it’s a disease that could be eliminated,” Yeske stated. He cited research that showed a low likelihood of M. hyo reinfection from neighboring finishing units.

“If you have a mycoplasma problem in your system, you likely have a system problem,” he said. “It’s not the neighborhood problem.”

Plus, the future holds new technologies like better diagnostics, new antibiotics and new testing procedures.

“Are there ways we can manipulate these tools to eliminate disease so we don’t have to deal with it?” he added. “What I’ve tried to do over time is, when something new comes out, [to determine] how could we leverage this into a new tool.”

In the past, the pork industry has eliminated diseases like pseudorabies without depopulation-repopulation.

“We had a very good vaccine with pseudorabies, and we were able to do eliminations by test and removal,” Yeske recalled. “Mycoplasma is another bug that lends itself well to herd closure and elimination.”

Watch the interview with Pig Health Today: