Stabilizing PRRS-positive herds through closure
Getting field strains out of herds now lessens blow on wean-to-finish performance.
Ann Hess, National Hog Farmer
Aug 01, 2022
When it comes to porcine reproductive and respiratory syndrome herd stabilization, Paul Yeske says producers have three options — allow the herd to remain positive, eliminate the field strain or depopulation/repopulation.
"I think we're more likely to see those viruses continue to change, at least in my experience over the years that's what I've seen, and that's where these new strains we're seeing with more persistent wean-to-finish problems," says Yeske. "One of the things that surprised me the most here recently is the number of depopulations/repopulations we've been involved with. I remember back in the early 90s doing lots of these for lots of diseases and here we are back at it again."
During a recent PRRSV Management Workshop in Iowa, the senior member of the veterinary team at Swine Vet Center, shared his tips to succeed on a herd closure as well as the status of the new PRRS 1-4-4 L1C variant. He says so far, the virus presents itself similar to other viruses. There's a rough two to four weeks, then the sows return to normal and there have been very low live born due to a high percentage of mummies.
"Some farms have gone longer but we've had farms that clean up in the 32-week time frame," Yeske says. "The first thing you do is stabilize the herd and get everybody exposed and so again you want to encourage the virus to move around. We let the aborts, off feeds out and let them move through the barn to try and get some exposure that way."
Yeske says one of his clients came up with the idea after dealing with porcine epidemic diarrhea, gaining six to eight months of scour control from the whole herd closure.
"By doing that whole herd feedback you kind of get that magic window like we did at PEDV, where you get good scour control while you're going through the closure," Yeske says...