Morphology of the adrenal gland blue rock pigeon (Columba livia L.)

Abstract

The blue rock pigeon (Columba livia L.) is a cosmopolitan, synanthropic or urbanist bird. Its use as a biological model to clarify the features of the structure of organs, systems and devices is incomplete. The adrenal gland plays an important role in the body of birds. Its hormones affect the growth and differentiation of tissues, regulate metabolism, affect the body's resistance to infections, stress, intoxication, low temperatures. The aim of the work was to find out the features of the morphology of the adrenal gland of the blue rock pigeon. Anatomical, histological, morphometric and statistical research methods were used. It was found that in the blue rock pigeon, the adrenal gland is a paired organ located ventrally from the cranial lobe of the kidneys. It has a pale yellow color, elongated-pyramidal or elongated-rounded shape, absolute mass of 0.019 ± 0.001 g. of the linear dimensions of the adrenal gland of the blue rock pigeon, the largest is the length (3.53 ± 0.04 mm), slightly smaller – the width (2.59 ± 0.16 mm), the smallest – the thickness (1.33 ± 0.03 mm). The left adrenal gland is longer and wider than the right adrenal gland. The adrenal parenchyma of the blue rock pigeon is represented by cellular strands of interrenal and suprarenal tissues, which are intertwined with each other. Indicators of their relative area in the peripheral zone (71.50 ± 3.46 and 25.83 ± 3.51 %, respectively), compared with the central zone (71.00 ± 3.50 and 26.17 ± 3.56 %, respectively), do not differ. Cells of the interrenal tissue of the adrenal gland of the blue rock pigeon are columnar or cubic in shape, with an eosinophilic colored cytoplasm and a rounded or oval nucleus, which is placed eccentrically. Relative to the cells of suprarenal tissue, they have a polygonal shape, basophilic cytoplasm, and a rounded, centrally located nucleus. Venous sinuses are registered between the cell strands of interrenal and suprarenal tissues. The wall of the venous sinuses is formed by flat endotheliocytes, in some places sinusoidal hemocapillaries invaginate in it. The relative area of venous sinuses in the peripheral and central zones of the adrenal gland of the blue rock pigeon is almost the same – 2.67 ± 0.33 and 2.83 ± 0.48 %, respectively. Clusters of multipolar neurons and nodes of the autonomic nervous system are recorded in the capsule, parenchyma, or outside the adrenal capsule of the blue rock pigeon. The established features of the macro- and microscopic structure, morphometric indicators of the adrenal gland of the blue rock pigeon can be used to create a base for its normal morphological characteristics, which will make it possible to assess the Morpho-functional state of the adrenal gland of birds of this species under the influence of various factors and pathology.