Position Statement: Sow housing at mating

Policy type: Position statement
: 7b
: Current
Date ratified
: June 2022

The New Zealand Veterinary Association (NZVA) has produced a position statement on the use of sow housing at mating to reflect the diversity of opinions within the membership.

  1. The NZVA supports the use of free access stalls to manage the welfare and physiological needs of sows in the immediate post-weaning period.
  2. The NZVA only supports confinement for the period required for performing artificial insemination.


  1. The physiology and behaviour of sows when on heat must be considered in proposed housing systems where sows are kept in groups.
  2. The immediate post-weaning period is stressful for newly-mixed sows due to re-establishment of the social hierarchy, the addition of young sows to the group and the onset of heat. This is especially important to smaller and subordinate sows as fighting and riding behaviour at this time may result in terminal injuries.
  3. Individuals within groups of sows need an opportunity to avoid negative social interactions during this time. Free-access stalls provide the best opportunity for sows to do this by enabling them to choose when to withdraw and when to reenter the group.

Guiding Principles

  1. Sows should not be confined unless this is absolutely necessary.
  2. The housing of sows in groups where possible is desired.

Further Reading

Knox R, Salak-Johnson J, Hopgood M, Greiner L, Connor J. Effect of day of mixing gestating sows on measures of reproductive performance and animal welfare. American Society of Animal Science 92: 1698 – 1707, 2014.

Rault J-L, Morrison RS, Hansen CF, Hansen LU, Hemsworth PH. Effects of group housing after weaning on sow welfare and sexual behavior. American Society of Animal Science 92: 5683 – 5692, 2014.

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