Pain Perception and Management
Introduction
The management of pain is quite a complex topic since animals cannot articulate pain the same way humans can. Pain management is entirely different depending on species and purpose of the animal. This reflection will summarize the most important key points and talk about how they relate to personal experiences with these topics.
What is pain?
Pain is described as an “unpleasant sensory and subjective emotional experience associated with actual or potential tissue damage or described in terms of such damage.” Consciousness is required for the pain to be perceived (Aminabaee et al., 2016: 1). On the 26th of February 2019 was the panel discussion ‘Schöner Töten’ with politicians about the recent animal protection violations in slaughterhouses in Germany. It was discussed when an animal is considered to be conscious and which movements of the animal indicate that the stunning procedure has failed. In Germany, this failure rate is 9%, which means 70 million animals per year (ARIWA, 2015). Since I, once every month, go to the slaughterhouse Leine-Fleisch GmbH to spend the last hours with the pigs before they get slaughtered, this touches me on a very personal level.
Anatomy and physiology of pain
In this module, it was taught that the information about a painful process is transmitted from the periphery to the central nervous system by a complex set of pathways. In the activism work, arguments like that plants are experiencing pain, too, and, therefore, it is not better to eat plants than animals are common. “Using a laser-powered microphone, researchers have picked up sound waves produced by plants; they release gases when cut or injured. Although not audible to the human ear, the secret voices of plants have revealed that cucumbers scream when they are sick, and flowers whine when their leaves are cut” (Dove, 2014, [online]). However, it is also known that plants do not have pain receptors or a central nervous system. Plants have mechanoreceptors which are reacting to touch and serve to maintain homeostasis, but they do not have the anatomy to experience suffering in a way humans and non-human animals do (Pearl, 2015). However, eating animals do harm even more plants, as animals are fed with plants (Fig. 1).
Figure 1: Plant consumption (Tam-Semmens, 2018).
Inter-species differences
A critical point in this module is that different species express the pain in different ways. To humans, it is essential to have specific knowledge to interpret if a particular species experiences pain and in which degree. Considering that experiencing pain is a subjective experience and, therefore, can be experienced differently in an individual, there are general differences in species. Especially noteworthy is if the animal is a predator, prey, or both. Pain is signaling weakness, so when grief is expressed, it makes an animal look like prey; the degree of expressed pain determines how comfortable a victim an animal is. To avoid looking like preyed upon counterparts, predatory animals will avoid showing signs of pain even when they feel it. From my experience, I found a pigeon on the street a while ago. She did not show signs of discomfort or injury, which was why I thought she probably needed some rest and sustenance. The next day she was dead, though, and I felt guilty. This lecture, yet again, showed that I should go straight to the vet, even if the animal appears to be healthy. Pigeons are prey animals, so maybe she suffered without showing any signs as to avoid being preyed upon.
Age
“... increases in pain sensitivity have been suggested to result from age-related anatomical, physiological, and biochemical changes, as well as compensatory changes in homeostatic mechanisms and intrinsic plasticity of some of the pathways involved in pain” (Yezierski, 2012: 1). Explanations like this are sometimes used when it comes to tail docking, castration (Fig. 2), and teeth cutting in young farm animals. All these procedures are typically performed without any pain relievers in the first week of an animal’s life. However, studies have shown that young animals are experiencing pain and distress even days after these surgeries (Prunier et al., 2003; Mainau et al., 2013). “During castration, physical resistance by the piglet, increased heart rate, and high-frequency (>1 KHz) squealing are reliable indicators of pain. One study showed that castrated piglets aged 3, 10, and 17 days produced a larger number of squeals than restrained, non-castrated animals (same group). The number of squeals was also greater in piglets at 10 and 17 days of age than in piglets at three days of age. This data suggests that surgical castration without anesthesia is painful at any age” (Mainau et al., 2013: 1).
Even though this indicates that there may be a difference in the pain experience determined by age, it could also mean that there is a difference in expressing pain at different ages. This study, at the very least, shows that at all ages, the piglets are experiencing pain and distress. In 2018, the German government decided to prohibit castration of piglets without anesthesia from 2021.
Figure 2: Castration of a piglet (Mainau et al., 2013).
I have been going to the slaughterhouse Leine-Fleisch for ten months now. At least once a month, I have noticed around ten trucks come to the slaughterhouse within the 3 hours we spend there. I never saw one pig with its tail still in place. They were cut 100% of the time (Fig. 3). Tail cutting is prohibited in Germany as of 1994. However, in 2018, over 90% of pigs had their tails cut in Germany (Unmuessig et al., 2019). The meat lobby is the fourth biggest industry in Germany (Beile et al., 2007). Because of their power and influence, the government tends to look the other way when it comes to violations of these, animal-related laws.
Figure 3: Cut tails (Taken by Author 2019).
Conclusion
In our days, it is broadly accepted that animals are sentient beings (Lisbon Treaty 2009, Article 13) and can, therefore, suffer.
It is pretty upsetting that we have all this knowledge about how animals experience pain, and still do not bother to perform cruel procedures such as tail cutting, mulesing, and castration without anesthesia. It is quite sad when money is put above morality. I am glad about lectures like this, as they give me background knowledge that I can use to convince people how our actual behavior is not acceptable.
Word count: 1077 words
References
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Lisbon Treaty2009 Article 13 Title II, opened for signature 13 December 2007. Official Journal of the European Union: Lisbon.
Mainau, E., Temple, D. and Manteca, X. (2013)Effect of castration on the welfare of pigs. The farm animal welfare fact sheet, 5. Available at: https://www.fawec.org/media/com_lazypdf/pdf/fs5-en.pdf[Accessed 06 March 2019].
Pearl, M. (2015) We Asked a Biologist If Plants Can Feel Pain. Available at: https://www.vice.com/en_uk/article/xd74nd/we-asked-a-botanist-how-sure-science-is-that-plants-cant-feel-pain-302[Accessed 05 March 2019].
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Tam-Semmens, H. (2018) A meat-eater actually ‘consumes’ about 18 times more plants than a vegan does. Graphic. Available at: https://www.quora.com/If-vegetarians-are-trying-to-save-all-the-animals-then-why-are-they-eating-all-their-food[Accessed 06 March 2019].
Unmuessig, B., Weiger, H. and Bauer, B. (2019) Tierhaltung in Deutschland – Wunsch und Wirklichkeit. Agrar-Atlas, 1, 34-35.
Yezierski, R.P. (2012) The effects of age on pain sensitivity: Pre-clinical studies. Pain Medicine, 13, (2), 27-36. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3565621/pdf/nihms342415.pdf[Accessed 05 March 2019].
