Lately, I came across a number of campaigns that called for an end of animal research in Germany. Some had a factual appearance, like the appeal from Doctors Against Animal Experiments not to donate to the ALS-Association. Others were heart wrenching, like the undercover video footage from a monkey lab by Stern TV. Yet others were open hate campaigns, like the newspaper advertisements agitating against Professor Kreiter. What they all have in common is that they create the impression that terrible suffering of lab animals stands in contrast to little or no benefit for humans. Any emotionally capable person has to conclude that this is highly unethical. Why then do animal research? Balancing harm against benefits – or caused suffering against diminished suffering – is indeed the core issue for the ethical assessment of animal research. Knowing the extent of both is indispensable for anyone who wants to form an opinion on the topic.
Three million animals die in experiments in Germany every year (92% rodents and fish). For comparison, 750 million animals die for meat production in Germany every year. Some animal rights activists are of the opinion that animals should be granted the same rights as humans. If we did that, animal research would be unjustifiable, as would be eating meat or keeping pets. Although most of us do not share that opinion, there is agreement that suffering caused in animal experiments should be as little as possible. For that reason, every application for an animal experiment requires an explanation as to why the respective question cannot be answered without animals (e.g. in cell culture), or using less complex animals (e.g. fly instead of mouse). Further, there are strict regulations for husbandry (e.g. cage sizes), animal care (e.g. administration of pain relievers following surgery), or humane killing. Naturally, such measures have limits, and in many experiments animals do suffer. People who deny this suffering or try to play it down impede an honest debate. Just as hindering for an honest debate is the false statement that animal experiments could be replaced today by alternative methods, such as cell culture, imaging methods, or computer simulation. All these methods are being employed enthusiastically today. However, in many cases only the combination with animal research can yield meaningful results. Based on discussions with friends, I realize that it can be difficult to evaluate the contradictory claims of opponents and supporters of animal research. Fortunately, this is not an irresolvable case of “one person’s word against another’s”. The information, on which the contradictory conclusions are based, is accessible to everyone. Everyone can retrace in detail that animal-free research methods have limits that can be bridged by animal research. If I want to know how a cancer cell reacts to certain substances, I can study that in cell culture. However, if I want to know how a cancer cell invades an organ and develops into a tumor, and what the role of the immune system is in that, I need an organ and an immune system, i.e. an animal. Modern imaging methods allow looking inside a living being without hurting it. Unfortunately, these methods have a poor resolution. For example, they can show where in the brain visual information is processed. However, if I want to understand how these brain regions turn light information into the conscious recognition of an object, I need a resolution that is only achievable in invasive experiments. Computers can only simulate something of which we have understood the principles. If a specific connection in the brain is unknown, it cannot be incorporated in any model. It is the expanding knowledge that we achieve through animal research that makes our models more accurate.
Almost all major medical breakthroughs of the last more than 100 years we owe to animal research, e.g. antibiotics, insulin for diabetics, vaccinations, blood transfusions, down to the most basic knowledge, such as that bacteria can cause disease. The ever repeating statement that animal research was irrelevant to human health is simply false. It is either ignorant or a lie, depending on who states it. If we abolished animal experiments today, we would have to abandon hope for finding effective treatments against ALS, Alzheimer’s, Parkinson’s, or Ebola, or to grow replacement for diseased organs in the lab, in the foreseeable future. An often missed benefit of animal research is species conservation. I must first study the physiological requirements of an animal before I can recognize what threatens the survival of its species in the wild. The population of Oriental white-backed vultures began to decline rapidly and without apparent reason in the 1990s. Initially, a virus was suspected. In 2004, it could be demonstrated that the analgesic diclofenac, which is administered to cattle by local farmers, is lethal to vultures. How can you demonstrate this? By feeding diclofenac-treated livestock to vultures in a controlled animal experiment. Diclofenac was banished and the species saved from extinction (for the time being). Without doubt, this study has caused suffering for the 17 vultures that died for it. Does this mean the experiment was unethical and it would have been preferable to inactively watch the species go extinct?
Our profession is to create knowledge. To this end, we use the most appropriate available instrument. For many questions, animal research is the only available instrument. We do not close ourselves to alternatives. We are the ones who develop and continuously improve them. When I decided for my career path, I thoroughly reflected on this balance – caused suffering against diminished suffering. I came to the conclusion that research with the aid of animal experiments is not only ethically justifiable but an ethical obligation for our society. We want to cure Alzheimer’s. We want to cure cancer. We want to understand how the brain produces consciousness. We do not know which of these goals we will achieve. But we do know that we must try.
The author conducts experiments with mice to study fatal familial insomnia. Findings from his work could benefit patients with this rare hereditary disease, as well as people with less dramatic sleep disturbances.