The basics of managing gilts for optimum pig production and longevity are well known. But successfully applying them requires meticulous attention to details, according to Jake Schwartz, DVM, Swine Vet Center.
“The best farms really embrace the details and make sure they’re executed 7 days a week,” Schwartz said. “That’s the difference between average farms and great farms.”
There are some basic rules he recommends for ensuring gilts realize their full genetic potential and become prolific members of the sow herd.
The first is managing disease threats like porcine reproductive and respiratory syndrome (PRRS), which can derail gilt performance. Schwartz suggests either keeping PRRS out of the herd or finding an appropriate way to handle it in a herd.
“[If] PRRS management strategy involves vaccine or serum exposure, the timing of those two events is important,” he said. “Do exposure early in the gilt’s life so when she farrows the first time, she’s not giving birth to PRRS-positive pigs.”
He also recommends avoiding PRRS exposure around time of breeding or right after breeding to prevent reproductive issues like mummies and abortions.
Parvovirus type 1 also causes reproductive issues with gilts, including increased rate of mummies, especially when they’re exposed for the first time post-breeding. All gilts should be vaccinated pre-breeding. If there is an elevated rate of mummies, there are some creative ways to get parvo exposure pre-breeding and minimize its impact.
No breeding on first heat
One breeding rule tops the list of production techniques for optimum gilt management. “It’s been well documented that when we breed an animal on her first estrus, we give up total born and farrowing rate,” Schwartz said. “Proper gilt management includes heat-no-servicing and breeding on a second or third heat.”
This rule is in place because a gilt’s uterus is still developing during first estrus and not quite able to handle a large litter, he explained.
Also remember not to equate gilt age with sexual maturity. “Some animals will cycle for the first time when they are 24 or 25 weeks of age. Others will cycle for the first time when they are 30 or 31 weeks of age,” he said. “It’s kind of a bell curve.”
Acclimate gilts early
Another technique for good gilt development is making sure nothing occurs to throw a gilt off feed in the 14 days prior to breeding. This means vaccinations should be completed and the gilts moved to their stalls at least 14 days before they are bred, Schwartz explained.
“Both of those things will, in some animals, throw them off feed around the time of breeding,” he said. “Then in subsequent farrowings, those gilts will have less pigs.”
Early estrus equals longevity
Time of puberty can be a trait used for gilt selection because gilts coming into heat early usually are the most prolific in the herd.
“When an animal comes into heat early or is one of the first third or half…we know those gilts tend to be more long-term, prolific members of the herd versus a gilt that first comes into heat at 30+ weeks for the first time,” Schwartz said. “Those gilts tend to be more short-term members of the herd and have lagging total born and farrow rate.”
The ideal gilt management program would select females that cycle by 30 or 31 weeks of age and younger. “In a perfect world, that’s what you would do,” he explained. “But unfortunately, given the constraints of some of the system’s farms, that’s often not the case.”