Posted 27 декабря 2021,, 14:08

Published 27 декабря 2021,, 14:08

Modified 24 декабря 2022,, 22:37

Updated 24 декабря 2022,, 22:37

Nature: carnivores get cancer more often than herbivores

Nature: carnivores get cancer more often than herbivores

27 декабря 2021, 14:08
Фото: Khao Sok Paradise Resort
This conclusion was made as a result of a large-scale study of animals from the zoo. According to scientists, this can be explained by the depleted microbiome of meat-eating animals.

Researchers from the University of Southern Denmark have studied the incidence of cancer in mammals living in zoos. To do this, they studied data on the health status of 110 148 individuals belonging to 191 animal species, reports Nature.

The results demonstrated that cancers are common in all mammalian species. However, when it comes to the degree of susceptibility to cancer, it differs from animal to animal. Carnivores are more likely to get cancer: more than a quarter of the leopards, foxes and red wolves in the study died for this reason. But ungulate mammals like sheep and antelopes, which are usually herbivores, have shown high resistance to this disease.

The researchers speculate this may be due to the low diversity of the microbiome in carnivores. Other possible explanations are insufficient physical activity (animals in zoos do not get food for themselves) and susceptibility to oncogenic viral infections.

Because the study took place among animals in zoos, scientists had a more accurate idea of the age of each participant. This is important because cancer is an age-related disease, and the age of wild animals is usually unknown. On the other hand, it is difficult to assess the incidence of cancer and its impact on populations living in the wild, since an animal that becomes seriously ill usually dies quickly - either from hunger or from the teeth of predators. In the course of the study, the scientists also examined the so-called Peto paradox - a known fact that the incidence of cancer is not directly related to the number of cells in the body.

Tumors are diseases that result from harmful mutations, and mutations usually occur during cell division. It would seem that the conclusion follows from this that animals with larger bodies, which have a longer life span and therefore undergo more cell division, have a higher risk of developing tumors. Several studies have confirmed this theory in humans: taller people do have cancer more often. However, this correlation does not work for animals: elephants and mice are equally likely to develop cancer, although the former are much larger and live much longer.

The results of a study by Danish scientists also confirm that the risk of developing cancer in different mammals does not depend on body weight and life expectancy. It seems that with the development of larger body sizes and increased life expectancy, a more effective mechanism for suppressing tumors has developed.

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