The new EFSA scientific opinion on the welfare of pigs on farm analyses the latest scientific and practical evidence on the welfare challenges caused by the most common rearing systems in the EU and gives detailed recommendations on how to prevent or manage them.  

The opinion presents 16 highly relevant welfare consequences along with their possible preventive and remedial measures. Additionally, the panel selected several animal based measures (ABMs) – e.g. the presence of certain lesions or behaviours - that can be reliably used for monitoring or enforcement purposes. 

Measuring animal welfare has traditionally been considered a challenge but this new report makes it clear that there are tools available that can help the legislator go in the right direction.

The most frequent welfare challenges identified by EFSA across pig rearing systems and categories of pigs were: 

• Group stress
• Inability to perform exploratory or foraging behaviour
• Soft tissue and integument damage
• Prolonged hunger (affecting dry sows and gilts, piglets, and boars) 

Of these, the EFSA considered that inability to perform exploratory or foraging behaviour was the most relevant for all the pig categories under consideration, including for sows during lactation and suckling piglets. This point warrants a reflection because current EU legislation on pig welfare mandates that all pigs should have access to appropriate enrichment materials to keep them meaningfully occupied with rooting, foraging, and exploring, all activities for which pigs are highly motivated. Unfortunately, this norm has been systematically flouted by the vast majority of the pig industry, with the effect that pigs continue to be kept in predominantly barren conditions and tail docked to manage tail biting. 

In this updated opinion, the EFSA reinstates in no uncertain terms that pigs have an intrinsic need to explore and to forage and that bad welfare follows if they are denied this opportunity. Thus, pen floor design should allow for the provision of appropriate enrichment materials in sufficient quantities. Alternatively, rubber mats should be placed in pens with fully slatted flooring. The substrates most suitable as enrichment materials are straw, hay and silage. Other materials are suboptimal, as already clearly stated in the European Commission’s (EC) Recommendation on measures to reduce tail docking. The EFSA also concludes that during a tail biting outbreak pigs should be immediately given novel and attractive organic enrichment materials.

Another conclusion of the report, an aspect that animal advocates have been stressing for decades, is that intensive indoor rearing is the practice that causes the most welfare issues. This means that, to be impactful in improving the welfare of the 146 millions of EU pigs, revised legislation will have to introduce profound changes as alternative, higher welfare systems currently represent less than 1% of the total number of pig farms. In particular, the EFSA recommends giving growing pigs more space compared to the current minimum legal requirements as this will have a positive impact on animal welfare and even on growth rates. Part of the flooring should be solid to allow the animals to rest by lying down and to facilitate the provision of bedding and enrichment materials.

In response to the successful “End the Cage Age'' ECI, the EC specifically required EFSA to assess the advantages, the welfare challenges and the mitigation measures associated with eliminating the use of individual stalls for gilts and sows and the report provides guidance on how this transition could occur. The EFSA concludes that gilts and sows should be permanently kept in groups. Hence, gestation stalls and conventional farrowing crates should no longer be used. As for farrowing and lactation, the EFSA concludes that, with the necessary adaptations in management and training of stockpersons, free-farrowing pens are as effective as conventional farrowing crates in terms of pre-weaning piglet mortality (14.2% for “fully crated” sows). Importantly, the EFSA highlights that temporary crating systems for farrowing and lactation should not be adopted unless their size is the same as free-farrowing pens and unless they can be easily converted into free-farrowing pens. This is a very important recommendation for the legislator to avoid the “enriched cage” escape route, an unscientific half measure that would cost sows and piglets yet more decades of unnecessary suffering. 

The opinion also stresses the importance of providing sows with nest-building materials, the most effective being those with longer structures provided in a deep layer, such as long-stemmed or long-cut straw or hay. Selection for large litters has several negative welfare consequences for sows and piglets alike and should be reconsidered. The EFSA recommends that selection for litter size should be limited to an average number of 12–14 piglets born alive.

The current minimum weaning age of 28 days for piglets should remain (and possibly increased based on further research). Additionally, the derogation allowing weaning at 21 days, which is largely used to maximise productivity, should be reconsidered. Piglets weaned at 28 days or later have better immunity and gut health and they may be less predisposed to tail biting later in life.

The opinion states that immunocastration and keeping entire pigs are preferable to surgical castration in terms of animal welfare and that in any case surgical piglet castration without anaesthesia and analgesia should no longer be performed. Additionally, tail docking should not be performed. The EFSA does acknowledge that these procedures can and should be avoided, stressing that effective pain relief protocols are mostly unavailable or impractical on farm. However, the report still offers recommendations on how to carry out these painful procedures when they are considered unavoidable. 

By contrast, we believe that - with the exception of individual animals or litters requiring veterinary care and if the procedures are carried out by a licensed veterinarian with adequate pain relief - revised pig welfare legislation should no longer include derogations to a full ban on pig mutilations, as there is a high risk that such derogations will become the rule (as is currently the case for tail docking).

On the specific request of the Commission, the EFSA also reached a consensus on seven ABMs that can be scored at the slaughterhouse to assess on-farm pig and cull sow welfare. At the moment, some indicators are already routinely collected for food hygiene and animal health purposes but they can also be very useful to monitor animal welfare on farm. Reliable classification systems and their harmonisation will be necessary in some cases to standardise the use of these AMBs in the future across Member States.

The widespread presence of chronic hunger, lameness and other injuries in some categories of pigs are also worrying and should be taken seriously in the upcoming revision of pig welfare legislation. In particular, chronic hunger in pregnant gilts and sows and the welfare of suckling piglets and breeding boars need to be urgently addressed, and in the case of boars also better studied.

This new EFSA opinion provides many useful indications on how to at least partially mitigate the serious animal welfare challenges in intensive pig farming. Of course, considering the opportunities ahead, it could have been even more ambitious. For instance, the mandate was limited to negative aspects of animal welfare. This is a missed opportunity as animal welfare science now recognises that kept animals should not only be spared suffering but should also experience positive mental states, which is the closest we can probably get to giving them “lives worth living”. The new legislation should definitely include this fundamental aspect, which lies at the core of our recent white paper on the revision of the EU animal welfare acquis.