Anatomic Features of the Spleen in Vertebrate Animals

Filtering, purifying, depositing functions of the spleen are closely connected with the system of blood circulation, which occurs in it. Moreover, the anatomical structure is determined by the design of vascular circulation in the body. The purpose of the work was defining the anatomical features of the vascular circulation of the spleen depending on the form of the organ in representatives of different classes of vertebrates. Material and methods. The spleen was taken from sexually mature animals of both sexes in the ratio of 1: 1 in the phase of morphofunctional maturity of the organ: catfish, frog; lizards, pigeon, chicken, quail, sheep, pig, horse, bovine and rabbit. Angiography of vessels was performed after the introduction of 76 % triombrast and ultrasound. Linear parameters of the body (width, length) were determined in mm by direct measurement. The index of spleen development was calculated as a percentage of the ratio of width to length. Results and discussion. The anatomical structure and morphology of the spleen are determined by the place of animals in the evolutionary series of vertebrates. The spleen of all animals under study was located under the ribs to the left. In poikilothermic animals, it was located in ripples. The spleen was fixed with a binder apparatus in homeothermic animals. The number of gates depends on the form of the organ and is ranged from 1 to 4. We detected the out of organ branching of the splenic artery. A tree-like type of vessel branching is characteristic for a spleen of round shape, the elongated form is characterized by the location of the arteries and veins by segments. In the phylogenetic series of vertebrates, the spleen shape is different and is determined by the index of spleen development (ISD): round-elongate (elliptical) is in the frog (ISD = 74.91 %), chicken and quail (ISD = 68.08 % and 63.29 ± 2.18 %); elongated form is in the lizard (ISD = 26.56 %), bovine (ISD = 32.50 %) and horse (ISD = 25.84 %); narrow and strongly elongated form is in a pigeon (ISD = 12.50 %), rabbit (ISD = 8.66 %), pig (ISD = 12.98 %); in the catfish it is triangular-elongated or trapezoidal-elongated (ISD = 77.02 %). In sheep, it has variable characteristics: triangular, elliptical or triangular-elliptic and trapezoidal (ISD = 69.81 %). Conclusions. The anatomical features of the spleen depend not only on the class and the species of animals. In the case of surgical intervention, an ultrasound examination of the body is required. It will allow a spleen-saving operation to be performed as effectively as possible. The following anatomical features must be taken into account: age, sex, breeding, and, most importantly, individual anatomical features.