Pig Courtship

Boar Foaming at the Mouth

On the left is a gilt who’s being checked out by a young boar on the right. A lady smells very special when she is in that special time of the month, e.g., ovulating, in heat, estrus, etc. This tends to make guys go ga-ga and foam at the mouth. At least, that’s what happens with pigs.

  1. Female enters estrus about every 21 days.
  2. Female’s vulva pinks and swells.
  3. Female releases heat pheromones.
  4. Boar detects female heat and foams at the mouth releasing pheromones.
  5. Boar nuzzles females belly and vulva.
  6. Female enters standing heat and allows boar to mount.
  7. They mate.
  8. They mate again ideally about 12 hours later to maximize the number of piglets.
  9. About three months, three weeks and three days later she farrows a fine litter of piglets.
  10. Nursing lasts about four to eight weeks. More than that tends to stress the sow and result in her becoming peakid and out of condition.
  11. Piglets wean
  12. About 3 to 7 days later the sow comes into heat and is ready to mate again.
  13. Rinse & repeat…

Note that ringing the nose of the boars, a practice done by some to keep the pigs from rooting, can lead to the boars tearing the delicate tissues of the vulva when he nuzzles his lady. We don’t ring our pigs, in part for this reason.

There is another reason boars will foam like this: competition with another boar. If boars were raised together they don’t tend to fight but if a new boar enters the picture you’ll see foaming and fighting. In smaller boars they don’t have tusks so the fighting consists almost exclusively of shoulder pushing, charges and spinning round and round. Bigger boars have significant tusks which can be razor sharp. A big boar battle can be dangerous. Don’t get between them!

We run our boars with our sows. Generally the boars leave the sows alone, not bothering them sexually unless the sows are near or in heat. This may work because we have large herds of 10 to 40 sows plus the multiple boars. If you just had a single boar with one or two sows he might pester them more. The thing to definitely avoid is a ratio of too many boars to sows. I would suggest not having more than one boar per six sows when running them together. On the upper limit I’ve heard it recommended that a ratio of one boar to 15 sows is about ideal.

I like running multiple boars in a herd because then they act as backup for each other. If a boar gets a cold it can lose fertility for several weeks. Having a backup boar means your less likely to miss matings. This of course means that you need boars that get along together. Typically this is done by having a younger shadow boar raised from a young age with the dominant boar.

Outdoors: 50°F/26°F Sunny
Farm House: 65°F/53°F
Tiny Cottage: 65°F/55°F