Rapid evidence assessment of farrowing systems that can improve piglet survival and welfare and sow welfare


The problem

There are animal welfare concerns about the continued use of permanent crating systems for

farrowing and lactating sows. Research into alternative farrowing and lactation systems has been active for over 40 years (especially in the UK), but the recent societal and political interest in this area has sparked a great deal more research and development internationally and greater commercial uptake of different systems and practices.

 Many countries are starting to phase out permanent crating of sows. The UK pig sector already operates at 40% free farrowing with commercial outdoor production. However, the indoor pig sector continues to be dominated by conventional farrowing crates. Uptake of alternatives has been limited, with constraints including farmer concerns over poorer piglet survival, ease of management and cost. There have been several scientific reviews attempting to summarise the evidence base for different systems but there remains a lack of clarity on what works and what will be compliant in the future.


Evidence was gathered from a range of sources, including peer-reviewed publications, grey literature and practical experience from early adopters of alternative systems and practices in the UK. Evidence was also provided by international contacts, where alternative farrowing systems are well established or being implemented as part of a transition towards less confinement.

The academic and technical information collated will be translated into narrative summaries. These summaries will be aimed at helping farmers understand different farrowing systems and practices that can be actioned on farm now (e.g. husbandry improvements) and/or facilitate the transition to systems that offer welfare improvements and consider sustainability for the industry.

This will provide AHDB with an overall picture of the practices applicable to both piglets and sows as well as evidence on stockperson wellbeing.


The report compares three levels of temporary crating, two levels of zero confinement and group farrowing, and two-stage multisuckle systems.

The report critically reviews the literature for the different systems identified considering:

  • Performance-prevalence of mortality
  • Welfare impacts and opportunities
  • Stockperson needs and farrowing systems
  • Economic and environmental considerations

Narrative summaries for each system describe the system, its effectiveness, where it works, the cost, how to do it well, the strength of the evidence and links to further information.

Project code:
21 June 2021 - 03 September 2021
AHDB sector cost:
£19,303 (plus VAT)
Total project value:
£19,303 (plus VAT)
Project leader:
SAC Commercial Ltd


REA for AHDB on alternative indoor farrowing systems Baxter Moustsen Bell 310821 (002)

About this project

The aim of the project was to produce a report summarising the current state-of-the-art farrowing systems and practices and how they best meet the needs of the piglets, sow and stockperson.

The research had several core objectives:

  • To provide rapid evidence assessments (REAs) on farrowing system practices that improve total piglet survival and pre-weaning performance, as well as to consider other aspects of the piglet’s welfare status within the five domains framework*
  • To provide REAs on welfare compromises and unintended consequences to the sows of any farrowing system practices, as well as practices that do address aspects of the sow’s welfare status within the five domains framework
  • To provide REAs on farrowing system practices that consider the well-being of the stockperson
  • To provide REAs on farrowing system practices that consider the economic and environmental costs
  • To translate REAs into narrative summaries for each practice that can be presented to farmers through AHDB’s Evidence for Farming Initiative (EFI)
  • To outline existing evidence syntheses and the nature of these syntheses, as well as to identify gaps in the evidence base as a focus for further research priorities
  • To outline where there are future data developments and technologies that may give greater insights than current research and data methods
  • To provide feedback on AHDB’s ‘organising framework for evidence’ and ‘generation and application of evidence standards’ working drafts

*The Five Domains is a model used to evaluate the welfare of an individual or group of animals, with a strong focus on mental well-being and positive experiences. The ‘Domains’ of nutrition, environment, health, behaviour and mental state essentially cover the same five elements as the Five Freedoms. However, the Five Domains explore the mental state of an animal in more detail and acknowledge that animals’ emotional needs are equally important as their physical needs.

Find out more about the Five Domains: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5575572/