Pain in food animals: a moral duty to prevent animals from suffering

Pain is a protective biological mechanism alerting to the onset of potential tissue damage, inducing both a sensory and emotional experience significantly affecting animal welfare².

Much research has been conducted in the last decade, leading to a better understanding of pain pathways and various mechanisms involved in pain expression, as well as the production of many recommendations and pain scoring tools; although there has been speculation about the fact that livestock pain management is far behind their companion animal counterparts.

In cattle, pain generally results from infectious diseases, injuries or lameness, but is also occasionally caused by humans, especially during routinely performed husbandry procedures.

Pain management, as well as other parameters such as stress and food, plays a critical role in animal welfare. As a matter of fact, chronic pain, and to a lesser extent acute pain, result in poor welfare of production animals^3. Being free from pain, injury and disease is a right and requirement for any animal. There is indeed a moral argument for reducing pain and discomfort in food animals, further highlighted by emerging societal and ethical considerations demanding improvement in welfare of food-producing animals, as well as transparent welfare practices, particularly when it comes to food safety and residue considerations, as sometimes pain management involves the widespread use of antimicrobial substances, with the risks associated with food safety and antimicrobial resistance.

Pain in food-producing animal is also closely intertwined with loss of productivity (milk, meat, wool production). In addition to the moral and ethical considerations of preventing animals from suffering, economic considerations are therefore also at stake. Pain affects food animal productivity, and therefore pain management has a direct impact on farmers well-being and income. An animal in pain won’t be able to produce enough, therefore leading to potential economic losses as well as impacting the farming community and potentially also creating psychological issues.

In reality, implementing pain management on farms can be a challenge.

Firstly, attitudes and approaches towards pain scoring and pain management in farm animals vary from one individual to another, therefore affecting the perception of pain and the subsequent implementation of pain management plan choices. Commonly performed husbandry procedures, such as disbudding (calves), dehorning, castration (piglets), calving, and tail docking (lambs), are often performed without the provision of any pain relief, despite the fact it is commonly acknowledged that such procedures cause acute pain. Providing pain relief during and after such husbandry procedures can be challenging for several reasons, including time, cost, safety and public health issues. It is now increasingly recognised that provision of pain relief for surgical husbandry procedures is required, or even mandatory in some countries, calling for an urgent need for the implementation of systematic adequate pain relief protocols.

So, while pain is often recognised and acknowledged in livestock, pain management plans are not systematically put in place. Costs, ease of use and administration of drugs, as well as legal restrictions specifically for the use of pain relief products in food-producing animal and who, whether it is the vet or the farmer, can administer these pain relief products, may be important factors preventing the use of analgesia in livestock⁶. Is there a way to find new approaches to pain management in farms and identify possible transformative patterns for pain management towards a more welfare centred approach?

Tail docking in piglets, which is the cutting or cauterizing of a part of the tail in the first week after birth to prevent tail biting in their later life, is a commonly performed husbandry procedure.

Research has suggested that tail biting can be avoided by providing pigs with enrichment materials such as straw, and that tail docking is not necessary^8,9. Despite this knowledge and a ban on tail docking according to European legislation dating from 2008¹⁰, many piglets are still routinely exposed to the painful procedure of tail docking, in many European countries except Finland and Sweden. This procedure is often performed without the provision of any pain relief, posing obvious welfare issues.

Enforcing legislation on pig welfare is one of the European Commission’s priorities in terms of animal welfare, although there are still lots to be done to achieve this. Netherlands plans to end routine piglets tail docking by 2030 with the Dutch pig sector. It is interesting to note that countries that have stopped routine tail docking seem to invest more in training for veterinary practitioners⁹.

Photo 2. Tail docking in piglet is a painful procedure banned in Europe, although routinely performed without any pain relief.

So, while it is often acknowledged that husbandry procedures such as tail docking are painful and should effectively be banned, these are still routinely performed, most often without any pain relief. Is there a way to mitigate pain in such situations? The development of easy to use, affordable and safe pain management strategies that would achieve rapid and sustainable uptake, and that could be voluntarily repeated by farmers even under financial restrictions, is challenging but of critical importance². Time, cost, safety and public health considerations should therefore be kept in mind while designing pain management protocols for on-farm husbandry procedures on food-producing animals. These pain management strategies should take into consideration potential residue concerns, especially the adequation of withdrawal periods with production goals, and ideally contribute to improved antimicrobial resistance stewardship by not systematically including antimicrobials in the overall treatment of affected cattle. Actually, the use of topical antiseptics could be part of such non-antimicrobial pain management strategies; topical antiseptics traditionally used in cattle include povidone iodine, chlorhexidine, hydrogen peroxide and cetrimide.

Research suggests that the use of topical or local anaesthesia, ideally combined with NSAIDs for analgesia, reduces pain during and after husbandry procedures and is therefore a robust and affordable strategy^2,3,11,12.  Recent research has shown that the use of a spray-on topical anaesthetic formulation* containing lidocaine, bupivacaine, adrenaline as well as an antiseptic (cetrimide) successfully mitigated the pain in lambs after tail docking⁷. This non-antimicrobial wound treatment, ideally administered in conjunction with parenteral or oral administration of an NSAID such as meloxicam, constitutes an affordable and efficacious method for farmers to improve animal welfare². The wound treatment has also been demonstrated to be safe and efficacious in pain management and wound healing incurred during surgical castration and tail docking of lambs^2,7,13, surgical castration and dehorning of calves^14,15, and debridement of hoof lesions in cattle to reduce lameness¹⁶. This product is licensed and used for anaesthesia and analgesia of aversive husbandry procedures in Australia and has been considered since as a pain management revolution in that country⁷.