Histological features of the atrioventricular node of the heart of a goat of the Anglo -Nubian breed

Abstract

 The synoventricular system of the heart of farm animals is still not sufficiently studied and has fragmentary reports in veterinary practice. The functional significance of this system for the body plays a huge role in its life. Independent generation of a nerve impulse by atypical cardiomyocytes,  first of all, the sinoatrial node, as well as other links of the synoventricular system, provides automatism, consistency, and synchronicity of contractions of the heart muscle. The Anglo-Nubian breed is a unique breed of goat due to its high indicators of meat and dairy products. Due to the rather "wet" climate of the North-Western region of the Russian Federation, which is characterized by high humidity, cold temperatures and windiness,  AngloNubian goats often suffer from diseases of the respiratory and cardiovascular systems. The aim of our study is to study the histological features of the structure of the atrioventricular node of the AngloNubian goat. 
The study was conducted on the basis of the Department of Animal  Anatomy of the St. Petersburg State University of Veterinary Medicine. A total of 10  carcasses of Anglo-Nubian goats aged 12 months were examined. To achieve the obtained results, the following research methods were carried out: fine  anatomical preparation and production of histological preparations.
As a result of the study, it was found that the atrioventricular node in an Anglo- Nubian goat at the age of 12 months is located ventrally from the oval fossa next to the coronary sinus located in the atrial septum on the side of the right atrial cavity. The atrioventricular node consists of contractile cardiomyocytes, P  cells, and T cells. We established morphometric parameters of the area of the cells of the atrioventricular node, their thickness, as well as the size of the diameters of their nuclei.