Peculiarities of pathomorphological examination of snakes

Abstract

The article presents data on the morphology of snakes and features of the pathomorphological study of representatives of this suborder of reptiles. There is also a brief description of the most common pathological conditions of reptiles, which are fatal without adequate veterinary care. Characteristic morphological features of snakes are described: a long narrow body, which is adapted for crawling, most of the internal organs are elongated, placed asymmetrically, some of them have lost their paired part. The skin of snakes is dry, almost devoid of glands, the outer layers of the epidermis form horny scales and shields. The snake's heart is three-chambered, three blood trunks independently depart from the ventricle separated by an incomplete septum: two aortic arches and the pulmonary artery, and the carotid arteries that supply arterial blood to the head and forelimbs depart only from the right aortic arch. Gas exchange occurs mainly in the lungs (in most snakes, the left lung is rudimentary) and the mechanism of respiration of the suction type. The digestive organs are elongated, and the liver is monocotyledonous. Metanephric kidneys provide isolation and water exchange. The body temperature of reptiles is not constant and largely depends on the ambient temperature (poikilotherm). Before the opening, the anamnesis is collected, and the type of reptile is determined. During the pathological examination, it is necessary to follow safety rules, especially when examining poisonous snakes. On external review, the skin is carefully inspected, attention is paid to the presence of ectoparasites (especially mites), remnants of the epidermis after the last molt, external damage, and so on. The mucous membrane of the oral cavity, teeth, external nostrils, cloacal slit are examined. To access the body cavity, a paramedial incision is made in the body cavity wall, bypassing large vessels. Internal organs should be discussed following the preservation of their anatomical and physiological relationships. In the process of pathomorphological examination, it is necessary to select material for histological, histochemical, bacteriological, virological, mycological, parasitological, and other types of laboratory tests to use a comprehensive approach diagnosis. Particular attention should be paid to diseases common to reptiles and humans (salmonellosis, leptospirosis).