I weaned the piglets last Thursday. The oldest litters had a nine week lactation, which is the longest ever for my farm.
Something I learned was the time it takes for sows to return to estrus while lactating, eight weeks. That’s the same as our beef cows when on good pasture.
Now the sows are my genetics and were ad libitum, (free access), fed a corn-soy diet. Different genetics and/or a different environment may lengthen the return to estrus. I’m betting it won’t be less, short of weaning, which is the typical stimulus for sows to return to estrus.
Most sows will show estrus five to seven days after weaning, which makes it fairly easy to plan breeding, even with artificial insemination using live boar semen which only lives for about a week.
I used Dru terminal boar semen from SGI to produce most of these piglets. I’m very happy with the vigor and muscling of the piglets. I’m hoping for excellent growth and meat quality as well. Click on the photo below and click again to enlarge and you’ll see the excellent muscling of the piglets.
Curiousfarmer 
Happy piglets!
What does “weaning” mean in this context — are the piglets simply separated from the sow all at once? Does this ever cause mastitis?
Yes, separated all at once. With a long lactation, (over three weeks), the piglets have started eating solid food so their distress is mostly psychological.
I went to a talk this winter and the speaker informed us of the original definition of “mastitis”, which is inflammation of breast tissue. So yes, the sows’ udders swell and I’m sure are uncomfortable for a few days. But I’ve never had an infection develop which required treatment.
Thanks!
A mother’s day facebook share (that oddly didn’t seem to get picked up much): “To the mothers who make our meat: the sows, the cows, the hens, the ewes, and the does — on this Mother’s Day we remember you, too!”