摘要：In the process of working with anatomical material supplied to the Animal Disease Diagnostic Center of the Primorskaya State Agricultural Academy, in the order of forensic examinations, a characteristic feature consisting in differences in the structure of the organs of animals living in natural habitat and in captivity was revealed. Evolutionary forces are reflected in the adaptability of animals to survive in the wild, honing adaptive characteristics and sweeping away all unnecessary things. Studying previously published works on the topic in question, it can be noted that the heart of animals in their natural habitat is slender, with a strong left side and relatively weak right side. As a rule, trabecular structures in such animals are smoothed, maximally “built” into the walls of the heart chambers. It is not often possible to find crossbeams as an element of myoendocardial formations in wild animals. However, for the internal structures of the human heart and domesticated animal species, this is not uncommon. There is an opinion that additional muscle-trabecular elements, such as: muscle crossbeams [3]; additional papillary muscles; pectinate muscles of the atria, located in a storey network - take part in the intensification of heart contractions and the creation of a swirling blood flow, providing its translational-rotational movement. This process can be considered an adaptive response to a decrease in physical activity during the evolution of a species, formed from birth to death of an organism. In the course of postmortem examinations, we examined the heart of a four-year-old female Amur tiger raised in captivity with the distinctive features of myoendocardial formations in comparison with other individuals of this species.
