THEMATIC REPORT: Best Practices Avoiding pain in castration

Brief literature overview

The literature review for Work Package 4: Castration of male piglets has been a traditional practice in European pig farming, mainly to prevent “boar taint.” This unpleasant odour and taste arise from the buildup of skatole and androstenone in uncastrated males. Since there are several animal welfare concerns related to surgical castration of male pigs, EFSA has recommended two primary alternatives: raising entire male pigs or using immunovaccination to suppress testicular function (EFSA, 2022). However, the issue of boar taint and consumer acceptance of immunovaccination complicate the shift away from surgical castration. Some supply chains have started to adopt these alternatives but surgical castration remains common in most Member States. Nevertheless, efforts have been made in these and other countries to avoid pain in castration, following EFSAs recommendations (EFSA, 2022), via banning surgical castration without analgesia and anaesthesia, which has been implemented in several European countries (Lin-Schilstra and Ingenbleek, 2021) and alternative approaches to surgical pig castration are gaining traction due to rising animal welfare concerns (De Briyne et al., 2016; EFSA, 2022). From the use of anaesthesia, to avoiding castration all together, there is a large diversity of approaches to this issue. These diverse strategies illustrate how cultural attitudes, market demands, and regulatory environments shape how countries address the welfare implications of piglet castration (Mateos et al., 2024).

Challenges

The Working Package 4 (WP4) deals to minimize the pain in castration. Challenges in this area relate to the conditions for carrying out physical castration, immunocastration or the production of entire males. The challenges are to ensure meat quality acceptable to markets and to accurately define the issues needed for viable, scalable and welfare alternatives supported by technical training to meet consumer demands.

• Challenges around physical Castration Practice
  • How should practical work be organised to castrate efficiently (local or general anaesthesia) related to farrowing system (stall housed or loose pen or outdoor production)?
  • Which are the best methods used to reduce the stress and pain associated with injections and piglets handling at castration in case of local or general anaesthesia (restraining method, delay before castration, udder access delay after castration)?
  • What ways to reduce castration costs according to anaesthesia practices (local or general)?
     
• Challenges around Immunocastation Practice
  • What additional cost/benefit of immunocastration at farm level for normal pigs (2 injections+ time) or heavy pigs (3 injections+ time) or local native breeds?
  • Which practical and efficient immunological castration protocol (clear calendar for 2 or more injections depending on pig slaughter weight), work organisation, arduousness, equipment and operators’ safety?
  • How to succeed in marketing and consumer acceptance with immunocastration?
  • Which ways to obtain quality products when using immunocastration (controls at farm level, detection of odorous carcasses at the abattoir)?
     
• Challenges around Entire Male Production
  • How management of entire male to reduce mounting, aggression and effects, like locomotion disorders, stress, …?
  • Which entire male breeding methods to reduce odour without changing carcass weight.
  • How to adapt entire male meat quality to fulfil the fresh meat market and processing industry?

Scoring methodology

Collected Good Practices were scored by the individual expert members of the Thematic Group. In order to assess how effectively each Good Practice addresses the theme of avoiding pain at castration and the related challenges specifically mentioned in the literature review, the experts scored each practice based on its excellence/technical quality (especially: challenges addressed, scientific evidence, efficacy, ongoing development, innovation), impact (especially: benefits for the pig sector, economic impact, knowledge exchange), and exploitation/ probability of success (especially: Feasibility, transferability, scalability, exploitation speed) by assigning each criterion a score on a scale from 0-5 (0=ineligible – 5=excellent).

Process of selection and discussion

In order to select the TOP5 of Good Practices, the Thematic Group experts met with the Work Package leader after individually scoring of Good Practices to discuss the selection of Best Practices. We had to analyse 11 Good Practices related to “pain alleviation at castration”, 5 Good Practices related to entire male production and 5 related to immunocastration. For this the final accumulated mean total scores and rankings were presented to provide the Thematic Group experts with an overview of the Good Practices after the scoring phase. During the meeting the first four Good Practices were kept due to highest mean score: 3 about immune castration and 1 about castration. It was the proposed to choose a BP about castration as a fifth Good Practice.

The TOP 5 for the WELFARMERS Round 1 are then the followings on the practices around 2 major challenges of WP 4:

• Immunocastration
  • Enhancing the value of immunocastration for 144 kg pigs fattened on litter since 2016: an ethical commitment for the pig sector
  • Immunocastration in large pens with 350-450 pigs, mixed sex. How to perform immunocastration in a herd with large pens.
  • Rationalising the practice of immunocastration: an effective solution for preventing mounting behaviour and guaranteeing carcass quality
     
• Reduce pain at castration
  • Local anaesthesia to reduce pain at castration
  • Respecting the Piglets in Castration with Local Anaesthesia

It was suggested for the next ROUND 2 of Good Pratices selection to be focused on Good practices around “Entire Male”.