Why pigs are used as organ donors for humans, and not monkeysBy Pictolic https://pictolic.com/en/article/why-pigs-are-used-as-organ-donors-for-humans-and-not-monkeys
Organ transplantation is a complex and risky operation, which is resorted to in extreme cases. Usually, a transplant is done if other methods of treatment are powerless and the patient's life is at risk. Unfortunately, only 5 percent of those who need a transplant can find a human donor. Difficulties arise both because of the lack of organs and because of their incompatibility with the patient's body. Therefore, recently animals have often been used as donors.
It is most logical to use monkeys as organ donors for humans. These mammals are as similar to us as possible, not only in appearance, but also in the structure of the body. Despite this, we don't hear about liver, lung, or heart transplants from primates to humans. But information about pig donors regularly appears in the press.
But why is an animal that is absolutely not related to us best suited for saving human health and life? Why does medicine not involve large apes? There are several reasons why primates are not suitable for us as donors.
One of the main reasons is the limited number of monkeys that can become donors. Chimpanzees would be best suited for this, but their population is decreasing every year. Also, breeding primates in captivity cannot be considered a way out — they reproduce poorly and grow slowly.
Ethical issues also play a role. There is still debate about how much intelligence is developed in great apes. Numerous experiments have proved that they are far from the human level, but animal rights activists do not think so. Attracting chimpanzees, orangutans and gorillas as donors would cause serious protests.
There is another problem that cannot be solved yet. Diseases of monkeys are poorly studied, and some of them are transmitted to humans. Therefore, by transplanting the organs of these animals to people, you can release the "genie from the bottle" and organize another epidemic with many deaths.
Strangely enough, but the disadvantages inherent in monkeys are completely absent in pigs. These animals are widespread all over the world, reproduce easily and grow quickly. For most of us, the death of a pig does not cause strong emotions. And how else, because the meat of these pets has been used for food for thousands of years. But the most important thing is that pig organs are ideally similar in shape, size, weight and location of vessels and nerves to human ones.
A pig's heart weighs an average of 320 g, and a human heart weighs 300 g. The lungs of an animal have a mass of 800 g, and in humans 790 g. For the kidneys, the ratio is 260 and 280 g, and for the liver — 1600 and 1800 g. Moreover, the Institute of Molecular Biology has found that pig growth hormone is 70 percent similar to human growth hormone. Even the body temperature matches!
Pigs began to be used in medicine even before the era of transplantology. Until the "artificial liver" devices appeared, patients with the affected organ were connected to the pig liver. Medical preparations developed for humans were also tested on animals.
Unfortunately, there is no complete compatibility between a human and a pig. Therefore, despite the achievements of science, sometimes there are rejections. Relatively recently, they started using a new way to reduce the risk. The human genetic material is injected into the pig embryo, which is planned to be transplanted later. In this way, a donor is grown, almost "related" to the patient.
The merits of pigs to medicine are marked by several monuments in different countries of the world. The people to whom they saved their lives also pay tribute to these animals. A pig valve has been working in Arnold Schwarzenegger's heart for several years. After the operation, the actor and bodybuilder completely excluded pork from the diet and started several decorative pigs at home.