BOOST GILT LITTERS WITH MORE MATINGS
If you’re not happy with the number of pigs in your gilt litters, perhaps you should consider multiple matings.
“The average number of pigs born alive per litter is 11 in the United States, but gilt litters are averaging only nine,” points out Mark Estienne, a University of Maryland extension swine specialist. “But producers can bring gilt litters up by trying multiple matings.”
Since ovulation occurs at approximately 40 hours after standing heat, you want to breed gilts or sows as soon after standing heat as possible to maximize egg fertilization. The typical practice is to breed after the onset of standing heat and then again 24 hours later, but gilts have been shown to respond better by performing a second mating 12 hours after the initial onset of estrus.
“Double matings like this increase the chance of breeding females at the optimum time prior to ovulation,” maintains Estienne.
Research shows the timing and duration of ovulation in gilts and sows is extremely variable. Therefore, it may be more important to concentrate on getting more matings in before ovulation rather than the exact timing of those matings.
Studies at North Carolina State University support Estienne’s multiple mating scheme. In gilts mated once, twice, three or four times during standing heat, the gilts mated four times produced 15 percent more pigs born alive than those mated only once. The timing of matings proved unimportant in determining litter size.
“To get more gilt matings done on your farm, you have to take into account boar inventory and labor,” says Estienne. “This breeding schedule makes a good case for artificial insemination.”