Ratification date: 16/07/26
Purpose
To provide a resource for veterinarians working with pigs to support veterinary input and highlight its importance when developing pig housing practices, to ensure housing systems meet the biological and behavioural requirements of pigs.
To advocate for the evidence-based, collaborative review, national adoption (where not already adopted), and legislative incorporation of the Model Code of Practice for the Welfare of Animals- Pigs 3rd Edition (MCOP) (Pigs, 2008) and, when available, the Australian Animal Welfare Standards and Guidelines for Pigs.
Policy
1. Pig housing for all classes and stages of production must optimise pigs’ nutritional, environmental, physical health, behavioural, and emotional needs to align with the five domains of animal welfare.
- Housing must provide access to feed and unlimited water to meet physiological requirements without undue competition.
- Housing must enable expression of important innate behaviours appropriate to stage/age of production such as rooting, foraging, nesting, and positive social interaction to meet emotional needs through suitable enrichment.
- All housing must be well maintained, frequently monitored and have emergency fail-safe systems (e.g., alarms or physical back-up systems) to ensure a hygienic, clean, lying environments free of accumulated faeces and waste.
- Housing environments must have suitable ventilation and air quality, light provision, ambient temperatures within thermoneutral zones and where appropriate shade and wallows, while maintaining good biosecurity.
- Housing must consider space allowances for all classes of pig to optimise welfare and health.
- Housing must promote overall pig welfare, health and production while providing a safe working environment for personnel.
2. Any development of Standards and Guidelines for pigs proposing legislative change must involve veterinarians as key stakeholders, with meaningful engagement and input to promote high standards of health and welfare for all classes of pigs.
3. The AVA supports the development of pig housing best practices through collaborative input that must include experienced veterinarians. Such practices must be grounded in robust evidence-based science, practical end-user experience, contemporary animal welfare principles, and be appropriate to Australian conditions.
4. The AVA advocates for ongoing review and research into housing systems and innovative monitoring of these systems for all classes of pigs. This should aim to minimise the need for and impact of confinement on the health and welfare of sows, boars, and piglets, while maximising positive welfare outcomes across all classes of pigs.
Background
Piggeries can house pigs at all or a subset of stages of the production cycle (pregnant sows, lactating sows, nursing piglets, weaners, growers, finishers and boars). Approximately 90% of domestic pigs in Australia are housed indoors while 10% are reared in a free range or outdoor-bred environment (APL, 2025). Indoor growing pigs are housed individually up to very large (hundreds) groups, in infrastructure that may be naturally or artificially ventilated, and which have solid, slatted or straw-based flooring.
Intensive indoor systems, when properly designed and operated protect pigs from climatic extremes and predation, improve ease of management, and enable close monitoring of the health and welfare allowing for timely interventions when required (Mkwanazi et al., 2019).
Pig housing in Australia is regulated by state/ territory legislation and complemented by the voluntary Australian Pork Industry Quality Assurance Program (APIQ), administered by Australian Pork Limited, covering ~90% of the national commercial pig herd (APIQ, 2022). Additional standards such as the Customer Specifications for Supply to Coles Supermarket Australia (CSC) (Coles, 2024), RSPCA Approved Farming Scheme (RSPCA, 2018) and Gestation Stall Free (APIQ, 2022) also exist. Housing standards including minimum space allowances prescribed by the Model Code of Practice for the Welfare of Pigs (which need to be reviewed to become Standards and Guidelines) must be met or exceeded for each class of pig, providing sufficient room and appropriate conditions for all animals and the ability to access resources without aggression or competition and to rest comfortably (Pigs, 2008).
Key welfare considerations in pig housing systems include:
a) The use of stalls to house individual pigs
b) The use of farrowing crates during birth and lactation
c) Space allowances for progeny pigs
d) The environment in which pigs are housed
e) The provision of enrichment
The use of stalls to house individual pigs
Stalls are named according to their use, to individually house pigs. Stall housing includes mating, gestation, farrowing and boar stalls. Tethering of pigs is prohibited in Australia. In a standard stall, pigs can stand up, lie down, extend their limbs when lying and take a step forward or backwards, but are unable to turn around.
Mating stalls house female pigs individually on a short-term basis, for the purpose of heat detection, controlled boar exposure and increased staff safety at the time of insemination. Most customer specifications currently permit the use of mating stalls for a maximum defined period of 24hours.
Gestation stalls (also known as ‘sow stalls’) house female pigs individually in early pregnancy, to reduce early pregnancy losses resulting from aggression that naturally occurs in group housed sows. While the MCOP (Pigs, 2008) allows the housing of females in a gestation stall for up to 6 weeks per pregnancy, 80% of the Australian commercial sow herd are APIQ accredited and keep sows in loose/group housing from at least five days after mating until one week before farrowing (Parliament of Victoria, 2024). RSPCA’s Approved Farming Scheme does not permit the use of gestation stalls, and the Coles supplier standard allows confinement in a gestation stall for 24 hours.
Boars are often housed individually in stalls to reduce aggression, injury, and mortality associated with mixing entire males. Boars raised together can usually be safely kept in small compatible groups or pairs (Rydhmer et al., 2013), whereas those not raised together risk severe aggression if co-housed. Most commercial breeder farms now use artificial insemination and maintain only small numbers of mature boars, with many having transitioned from stalls to individual pens (minimum 6 m²). Larger boar studs may still use stalls in some cases.
The current Model Code of Practice requires boars in stalls or pens smaller than 6 m² to be released for exercise at least twice per week. The AVA supports moving away from prolonged stall housing towards systems that better allow boars to express innate behaviours while maintaining staff safety and hygiene standards.
a) The use of farrowing crates during parturition and lactation
Traditional farrowing crates confine sows during parturition and lactation in a way that allows them to stand, lie down, extend their limbs when recumbent but prevents them from turning around. While they are recognised by the industry and many veterinarians as an effective tool to reduce piglet mortality by minimising the risk of sows laying/crushing piglets, as an option to support the health and welfare of sows and piglets, and as supporting staff safety, they do restrict the sows’ ability to move freely and express natural maternal behaviours.
Alternative indoor farrowing options for sows include freedom farrowing systems (Free Farrower, 2021), temporary or adjustable confinement allows expansion of the sow area post-farrowing, farrowing pens with maternity rings (Plush et al., 2024; SunPork, 2025) which limit the sows lying area to protect the piglets from crushing while permitting freer movement and fully free-farrowing pens (PigSAFE, 2021b). These systems have been designed to minimise or eliminate sow confinement incorporating piglet protection features (e.g., creep areas, anti-crush rails or rings) while enabling greater expression of natural maternal behaviours. A consideration with less confinement is staff safety and possible higher piglet mortality (Glencorse et al., 2019), and research continues in this area.
In outdoor farrowing systems, sows typically use enclosed huts with bedding material, allowing greater freedom of movement, turning and natural nesting behaviours. However veterinary experience and evidence indicate these systems can increase piglet mortality from laying/crushing but can reduce stillborn numbers (Dumniem et al., 2023; KilBride et al., 2012), increase disease transmission risks from reduced biosecurity (Makovska et al., 2023), and heighten staff injury potential compared to intensive indoor housing.
b) Space allowances given to progeny pigs
The minimum space requirement for pigs (m2/pig) as outlined in the Model Code of Practice (MCOP) (Pigs, 2008), is determined by the average weight of the pig class and applies to all housing types. An additional 30% space is required for straw-based housing to accommodate dunging areas. However, the current MCOP, lacks detail on essential elements in both indoor (e.g., minimum percentages of solid floor lying areas, excluding internal structures (like feeders and water troughs) from the available space calculation)
Space allowances are legislated in most Australian states and territories, and are audited annually under APIQ (APIQ, 2022). However, the MCOP (Pigs, 2008) is based on dated research and lacks provisions for essential elements. Recent evidence suggests that space allowances greater than current Australian minimums are likely to improve welfare (reduced aggression/stress) and performance (growth rates, though further research under commercial conditions is needed to optimise recommendations (Chidgey, 2024).
c) The environment in which pigs are housed
Housing systems must maintain ammonia levels below 10 ppm to prevent respiratory inflammation and immunosuppression, especially when combined with dust (Buoio et al., 2023; Jones et al., 1996). Reliable fail-safe ventilation systems are essential to prevent heat stress and respiratory disease. Pigs should also be provided with adequate lighting (minimum 40–50 lux for at least 8 hours daily with a distinct dark period) and noise levels below 85 dB to support circadian rhythms and minimise chronic stress (European Commission Directive, 2003). In free-range systems, adequate shade, wallows, and sufficient space must be provided to enable natural thermoregulation and behaviour.
d) The provision of enrichment
The provision of environmental enrichment has been demonstrated to enhance welfare and mitigate negative behaviours, including aggression, bar-biting, sham-chewing, and tail biting 1 (Mkwanazi et al., 2019; Ralph et al., 2017; Winfield et al., 2017). To minimise aggression associated with group mixing and to optimise both welfare and production outcomes, pigs should be housed in stable groups from weaning to market wherever possible (Pigs, 2008). When mixing cannot be avoided, environmental enrichment must be provided to all pigs, including growing stock, sows, gilts, to help reduce aggressive behaviours and improve welfare. Enrichment provision must be provided to all pigs and is discussed in detail elsewhere.
Recommendations
- The AVA advocates for a complete phase-out of gestation stalls as soon as practicably possible.
- The AVA encourages prioritisation of alternative farrowing systems that minimise the need for confinement while protecting piglets.
- The AVA encourages transitioning from boar stalls to enriched individual pens or, where safe and socially compatible, group housing with sufficient space for free movement, supported by industry investment and phased implementation.
- National Standards and Guidelines must be developed and legislated uniformly across jurisdictions to replace the MCOP, addressing gaps identified in the current MCOP. The legislation should reflect current and emerging evidence to enhance health and welfare of all classes of pigs.
- Governments should provide financial support for research into reduced-confinement alternatives for sows and boars, in collaboration with industry investment.
Other relevant policies and position statements
- Enrichment for commercially raised pigs
References
APIQ. (2022). APIQ_Standards_Manual_V5.2_12_2022_0. https://australianpork.com.au/sites/default/files/2022-12/APIQ_Standards_Manual_V5.2_12_2022_0.pdf
APL. (2025). National Environmental Guidelines for Indoor Piggeries (NEGIP)_5e_2025. https://australianpork.com.au/sites/default/files/2025-05/National%20Environmental%20Guidelines%20for%20Indoor%20Piggeries%20%28NEGIP%29_5e_2025.pdf
Buoio, E., Cialini, C., & Costa, A. (2023). Air quality assessment in pig farming: The Italian classyfarm. Animals, 13(14), 2297.
Chidgey, K. L. (2024). Review: Space allowance for growing pigs: animal welfare, performance and on-farm practicality. Animal: An International Journal of Animal Bioscience, 18 Suppl 1, 100890. https://doi.org/10.1016/j.animal.2023.100890
Coles. (2024). ColesSupplyStandards. https://www.supplierportal.coles.com.au/csp/supplychain/ColesSupplyStandards.pdf
Dumniem, N., Boonprakob, R., Parsons, T. D., & Tummaruk, P. (2023). Pen Versus Crate: A Comparative Study on the Effects of Different Farrowing Systems on Farrowing Performance, Colostrum Yield and Piglet Preweaning Mortality in Sows under Tropical Conditions. Animals, 13(2), 233. https://doi.org/10.3390/ani13020233
Eurpoean Commision Directive. (2003). European Commission Directive. Amending Directive 91/630/EC Laying Down Minimum Standards for the Protection of Pigs. 2003/93/EC. https://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2001:316:0036:0038:NL:PDF
Free Farrower. (2021). 360° Freedom FarrowerTM. https://www.freefarrowing.org/farrowing-systems/temporary-crating/360-farrower/
Glencorse, D., Plush, K., Hazel, S., D’Souza, D., & Hebart, M. (2019). Impact of non-confinement accommodation on farrowing performance: A systematic review and meta-analysis of farrowing crates versus pens. Animals, 9(11), 957.
Jones, J. B., Burgess, L. R., Webster, A. J. F., & Wathes, C. M. (1996). Behavioural responses of pigs to atmospheric ammonia in a chronic choice test. Animal Science, 63(3), 437–445. Cambridge Core. https://doi.org/10.1017/S1357729800015332
KilBride, A. L., Mendl, M., Statham, P., Held, S., Harris, M., Cooper, S., & Green, L. E. (2012). A cohort study of preweaning piglet mortality and farrowing accommodation on 112 commercial pig farms in England. Preventive Veterinary Medicine, 104(3), 281–291. https://doi.org/10.1016/j.prevetmed.2011.11.011
Makovska, I., Dhaka, P., Chantziaras, I., Pessoa, J., & Dewulf, J. (2023). The Role of Wildlife and Pests in the Transmission of Pathogenic Agents to Domestic Pigs: A Systematic Review. Animals : An Open Access Journal from MDPI, 13(11), 1830. https://doi.org/10.3390/ani13111830
Mkwanazi, M. V., Ncobela, C. N., Kanengoni, A. T., & Chimonyo, M. (2019). Effects of environmental enrichment on behaviour, physiology and performance of pigs—A review. Animal Bioscience, 32(1), 1–13. https://doi.org/10.5713/ajas.17.0138
Parliament of Victoria. (2024). Inquiry into pig welfare in Victoria.
Pigs: Model code of practice for the welfare of animals (3rd ed). (2008). CSIRO Publishing.
PigSAFE. (2021). PigSAFE. https://www.freefarrowing.org/farrowing-systems/individual-farrowing-pens/pigsafe/
Plush, K., Lines, D., Staveley, L., D’Souza, D., & Van Barneveld, R. (2024). A five domains assessment of sow welfare in a novel free farrowing system. Frontiers in Veterinary Science, 11, 1339947.
Ralph, D. C., Cronin, D. G., & Bld, J. D. (2017). Enrichment in the sucker and weaner phase altered exploratory behaviour and the immune system of pigs. Final Report APL Project 2015/038. South Australian Research and Development Institute (SARDI).
RSPCA. (2018). 2018-11_PIGS_Standards (Version 5th). https://rspcaapproved.org.au/wp-content/uploads/2022/03/2018-11_PIGS_Standards.pdf
Rydhmer, L., Hansson, M., Lundström, K., Brunius, C., & Andersson, K. (2013). Welfare of entire male pigs is improved by socialising piglets and keeping intact groups until slaughter. Animal: An International Journal of Animal Bioscience, 7(9), 1532–1541. https://doi.org/10.1017/S1751731113000608
SunPork. (2025). SunPork Group Website—Maternity Rings. SunPork Group Website. https://www.sunporkgroup.com.au/maternity-rings/
Tails. (2025). Tail Biting Risk Support Tool. https://tailsdst.com.au/
Winfield, J. A., Macnamara, G. F., Macnamara, B. L., Hall, E. J., Ralph, C. R., O’Shea, C. J., & Cronin, G. M. (2017). Environmental enrichment for sucker and weaner pigs: The effect of enrichment block shape on the behavioural interaction by pigs with the blocks. Animals, 7(12), 91.