Морфологічна характеристика шкіри та волосся клінічно здорових собак та котів

Abstract

The article describes the histological characteristics of the skin of clinically healthy domestic dogs and cats, presents morphometric data on the thickness of the skin, layers of the epidermis, the area of the sebaceous glands and hair follicles; describes sexual and seasonal skin replacements in domestic dogs and cats, common in the east of Ukraine. The material for research is the skin of clinically healthy dogs and cats. Research method is histological. Punch-biopsy of skin fragments was performed in animals on the right from the middle of the lateral surface of the back. Fragments of skin after fixation in 10 % neutral formalin were examined by paraffin, followed by staining of slides with hematoxylin-eosin and by gelatin impregnation, staining with Sudan II, hematoxylin of Karachi. In horizontal and vertical skin sections, the following was investigated: the thickness of the epidermis, papillary and reticular layers, the length and width of the sweat and sebaceous glands, follicle of the hair, the location of hair bundles and the ratio of secondary follicles to primary ones. The histological characteristics of skin and derivatives in dogs and cats have been established. The information obtained from morphometric histostudies indicates significant fluctuations in the values in cats depending on the season; the difference in skin thickness in winter and summer reached 1407 μM and had the same parameters in females and males. The papillary and reticular layers of the dermis correlated with the total skin thickness as 53.9 and 60.3 % in winter and 45.4 and 38.7% in summer, respectively. Epidermal seasonal changes were less significant. The papillary layer of the skin of the domestic cat was more developed than the reticular layer, in contrast to the dogs. The area of the basal sebaceous glands in cats averaged 0.05 mm2 in summer and 0.013 mm2 in winter. In domestic dogs, skin thickness and hair density did not depend on seasonal changes, but on the sex of the animals; in females, the skin was on average 496 + 183 microns thick, and the density was not significantly higher than in males. The area of the sebaceous glands averaged 0,020 mm2 in dog, in cats 0.013 mm2 in summer and in winter – 0.05 mm2.