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Vulval Biting

This is a common condition in sows loose housed in the last 5 - 6 weeks of pregnancy.

Sows bite at the vulva, which has become swollen with advancing pregnancy, particularly when access to food fed on the floor is poor. A sow bites the vulva to gain access to feed. The trauma causes haemorrhage, infection and the development of scar tissue which may inhibit the farrowing process.




  • Blood on the noses of sows.
  • Blood around the vulva of the affected sow.
  • Haemorrhage.
  • Swollen red torn infected vulva.
  • Occasionally inappetence.
  • Scar tissue.
  • Abscesses.
  • Low grade infections.
  • Ascending womb infections discharges.
  • Repeats in some badly affected sows.
Piglets, Weaners & Growers
  • N/A

Causes / Contributing factors

  • Group behavioural abnormalities.
  • Vulval biting is much more common in pens that are long and narrow rather than those that are wide. There is less competition at feeding time in a wide pen.
  • Vulva biting is also common when electronic feeder systems are used. It requires careful stockmanship and good pen design to prevent it.
  • There is a relationship between vulva biting and feed intake, the size of the feed pellet, the type of floor surface and the bedding used. Many cases occur in the last 3 - 4 weeks of pregnancy.
  • High stocking densities predispose.


Made from the symptoms, examine the vulva for trauma.

May be confused with cystitis.

Further Reading

Click on the links below to find out more about this disease, including treatment, management control and prevention information. The top link is the main article on this disease.