This article was first printed in Spiegel on 28 December 2017 and is reprinted here in the English translation.
A moderated debate between Prof. Stefan Treue, (pictured below) animal physiologist, neuroscientist and director of the German Primate Center – Leibniz Institute for Primate Research in Göttingen and Jörg Luy, philosopher, veterinarian and animal ethicist at the Research and Advisory Institute for Applied Ethics and Animal Welfare Instet in Berlin.
Spiegel Moderation: Ann-Katrin Müller and Philip Bethge.
SPIEGEL: Mr. Lucy, researchers in Japan have recently transplanted cynomolgus nerve cells that had previously been bred in the laboratory. The monkeys were suffering from Parkinson’s disease. After the transplant they could move better again.
Luy: That sounds great, but it’s not, because Parkinson’s disease was artificially caused in the animals. If you want my short ethical assessment: unacceptable.
SPIEGEL: Would you stick to this assessment if a close relative of yours had Parkinson’s and would benefit from the monkey-engrafted transplant?
Luy: Unfortunately, we have a Parkinson’s case in the family. But that does not change my assessment. It is unlikely that the Javan monkeys have voluntarily consented to this transplantation experiment, let alone the procedure that artificially causes Parkinson’s disease. Therefore, the experiment is ethically not allowed. One would never make such attempts on people.
SPIEGEL: Does not the healing of a disease have a higher ethical value?
Luy: That’s a very dangerous thought. If you continue to spin, you will end up with human experiments. They might also help patients. If we even weigh process and utility, then the crucial point is: is it worth it for the test object to participate in the experiment? Is it a fair deal?
SPIEGEL: Mr. Treue, in Germany about 3,000 primates are currently being kept for animal research, especially crab ape and rhesus monkeys, and there are tens of thousands worldwide. Socially, experiments on primates are apparently considered justifiable throughout the world. Also from you?
Treue: No one is happy about animal testing, but on certain research questions they are necessary and justifiable. Exactly this is also the legal situation: There is no general prohibition of animal experiments, but a process of consideration. In other words, experiments on animals are prohibited unless a long list of conditions are met.
SPIEGEL: What does “weighing” mean? If cancer patients would benefit from experiments on primates, then you can do them?
Treue: The criterion is whether the expected suffering is ethically justifiable. It is about the difficult balance between the potential suffering of the animal and the gain in knowledge for research, medicine and society.
Luy: I often hear this answer: Animal experiments can be imagined for serious human illnesses, but you cannot accept them for being succinct. But there is a mistake in thinking. Here are the same mechanisms used as in shopping. People buy a product if the price-performance ratio is right. Translated on animal experiments this means: For the benefit of X, the stomachache Y is acceptable, which I have with the experiment. But this is not how our sense of morality and justice works. We change the perspective, even more, we transform ourselves imaginatively into those affected, be it humans or animals. If, from the point of view of the affected individual, we cannot accept the treatment, then our sense of morality signals: unacceptable.
SPIEGEL: How do you measure the suffering of the experimental animals, Mr. Treue? You cannot ask the monkey how he is and how much pain he finds acceptable.
Treue: This can not be measured with absolute reliability, but we can, for example, monitor behavior or physiological reactions such as the release of stress hormones. But right: An animal cannot agree with the experiments, because he lacks the cognitive abilities. Ultimately, we carry out this process of consideration. The protection and needs of people are particularly important.
SPIEGEL: Because of our cognitive abilities?
Treue: No, because we are more capable of suffering.
SPIEGEL: So we can also sense the suffering of the other, in this case the primate?
Luy: We feel it is disrespectful to harm others. Primates look similar to us, so we have more respect for them than for animals that are less similar to us.
SPIEGEL: Surely it cannot be an ethically relevant criterion if I feel close to a species of animal optically.
Luy: Yes, that’s a mistake. But these mistakes are everyday. People would be outraged if someone pulled a gorilla on a leash behind them. No one gets upset with a dachshund.
SPIEGEL: Mr. Treue, under what conditions is an attempt on primates justified for you?
Treue: For example, if there is no alternative species for a question. If I can test a vaccine on a mouse as well as a primate, only the mouse test is approvable. If there is a good computer model, no animal experiment is justifiable.
Luy: How are you weighing up? When do you come to the point where you say that an animal experiment is ethically unjustifiable for this research question?
Treue: The criterion is whether the question is of great importance.
SPIEGEL: Are there any questions you would not research because you would not accept the burden of primates?
Treue: But yes. Classic examples are cosmetics or weapons research. These are not essential questions for society. The brain, on the other hand, whose function we are investigating, is so central to our self-understanding, to medical and fundamental biological issues, that a better understanding of its functioning is of great importance.
SPIEGEL: Is it mandatory to use primates in certain drug tests?
Treue: Normally, two species of mammals are used, and depending on the type of drug and the risk potential one sees, a primate species is often present – especially in the toxicity test.
Luy: So most of the primates get poisoned …
Treue: It depends on whether the animals belong to a control group or a measurement group.
Luy: For the measuring group, the experiment usually ends lethally.
Treue: Such attempts have become much rarer, and primates play a minor role. Sometimes, however, there is nothing left. Doctors and patients must know at what dose a drug that otherwise works well, is life-threatening.
SPIEGEL: What kind of experiments do you do at the Primate Center in Göttingen?
Treue: I try to find out how the brain works, how brain processes, nerve processes take place in healthy animals.
SPIEGEL: What is this about? For a benefit or purely knowledge gain?
Treue: This is an interesting choice of words by you. The gain in knowledge is nevertheless a benefit. But you probably mean a medically definable benefit. If you take the position that every single animal experiment would have to cure a patient, then I have to answer you: That’s not how science works. A fundamental experiment always has an unknown result and initially no obvious and immediate medical benefit. Historically, however, those scientists who made the biggest breakthroughs wanted to openly understand how biological systems work.
SPIEGEL: Mr. Luy, are we not even obliged to use primates for research because it would be unethical to forego gaining knowledge?
Luy: No, because theoretically there would be a much better method: we could experiment with ourselves. And that’s the really exciting question for the ethicist: For what reason are we not experimenting with humans? There seems to be a limit to research? No patient has ever complained, as far as I know, that the research is no further because it has not resorted to, for example, people sentenced to death.
Treue: I hear this argument again and again. And it is by no means the case that there is a clear limit. There are indeed experiments made on people. Only: how far are they allowed to go? For example, we do not allow the sale of organs. At the same time, there are many medical studies involving people, even though they are not patients at all. They do that because they think it helps society.
Luy: Wait a minute, the participants get financial compensation. This is not altruism, but a deal. Without money you have to search your human subjects for a long time.
Treue: In a commercialised medicine, a subject would be pretty stupid to give up the money. Nevertheless, there are a lot of studies where you have to spend hours in an uncomfortable position and only get the money for the bus ride.
Luy: The deal is fair and people can decide for themselves if they want to join in the experiment. Why does that not apply to animals as well? The ethicist Peter Singer was one of the first to ask the question in 1975: Why do we actually measure with two different measures? Why do not we ask the animals? Or at least put ourselves in their position and decide consistently from their point of view, whether an experiment is okay, because the profit is an appropriate compensation for the suffering?
Treue: That can never work, because it’s almost always about a benefit that does not benefit the test animal itself.
Luy: That’s not the point. Just like the sports student volunteering for a medical impact assessment, I could reward the animal for volunteering. In fact, a pharmaceutical company has investigated whether it is possible to voluntarily make blood collections in pigs. Lo and behold, the pigs stopped for a single treat and had their blood taken. Apparently they found the deal fair. If animal experiments were that way, they would be ethically clean.
SPIEGEL: Mr. Treue, you fix your monkeys in so-called primate chairs. There, the animals can not move their heads during the experiments. Do the monkeys voluntarily consent to it?
Treue: It’s all reward-based.
Luy: Excuse me? They give the animals nothing to drink for days, they finally get something at the test. That’s not a reward.
Treue: No, that’s wrong! The animals are given the opportunity to drink daily, and not only their hydration, but also their health is under daily observation.
Luy: To my knowledge, the animals have not been able to move without thirst.
Treue: They are already working on the tasks, but not as long as when we can use their favorite liquid as a reward.
Luy: See? Someone from the German Animal Welfare Association told me that they had people as fixed as the animals in the primate chair. The subjects would have begged after 20 minutes and whined that they are released again.
Treue: And you believe that? There are many medical interventions in which patients are not allowed to move their heads. They also do not whine after 20 minutes. The primates become accustomed step by step to not being able to move their heads while in the chair. The animal is rewarded for every task in which it participates. Otherwise, there is no reward, but no punishment. This ensures that the animal remains healthy. Now we can argue about when it is suffering when one is thirsty.
SPIEGEL: Do you see the prospect of getting along in research without animal research?
Treue: We are already working a lot with computer models. We also use imaging techniques. Apart from the complex ethical questions, this is much cheaper than experiments with primates. If I knew how to do my research without animals, I would immediately abandon the primates.
Luy: Scientists are very creative people. There are many other ways to do research, including the target species, i.e. humans. Although this takes longer in case of doubt, the results are more useful. I cannot think of anything for which there could be no alternative to animal testing.
Treue: I can think of almost every medical breakthrough. We can meet again in 100 years. Maybe then the research is so far that primate experiments are superfluous.
SPIEGEL: Mr. Luy, Mr. Treue, we thank you for this conversation.