The bat skin shows an unusual morphology that corresponds to flying adaptations but also performs multiple functions including a protective barrier against microbes and parasites. Here, we compare the microscopic structure of the skin and hairs collected from the membranes with other body parts in the Common Pipistrelle (Pipistrellus pipistrellus) in relation to parasite availability. Statistical analysis of whole‐skin thickness revealed two main groups according to body regions; the first with thin skin (wing and tail membrane) and the second with thick skin (head and dorsum, abdomen, footpad). The density of hair was evaluated by a novel method, and it revealed that the density was significantly higher in the head region than in dorsal and ventral body parts. These differences possibly play a role for bat ectoparasites when choosing the preferred region of their host. Along the axis of each hair, the scale morphology was found to be variable. Hair morphology, however, did not vary among body regions. Mast cells were numerous in the hairy areas around vessels and hair follicles of the dorsum and abdomen, which are easily accessible to ectoparasites. Increased numbers of mast cells in hair‐bearing skin are part of the host adaptation system in parasite‐preferred locations.

Ultrastructure of the olfactory epithelium was studied in ovine foetuses aged 74 and 79 days, in newborn and 30-day-old lambs, and in a 730-day-old sheep. Differentiation of apical parts of supporting cells, cilia on sensory cell dendrite endings, redistribution of centrioles from dendrite into endings and presence of a large amount of glycogen inclusions in supporting cells were apparent at day 74 of the intrauterine development. Supporting cells represented the major portion of the olfactory epithelium at day 79. The epithelial surface was covered by a dense network of cilia, but distal segments were seen only sporadically. The amount of microtubuli increased in dendrite cytoplasm. At birth, the cytoplasm of olfactory endings contained numerous light vesicles, mitochondria and centrioles. The free surface of supportive cells was furrowed into numerous microvilli. Distal segments of olfactory cilia were observed at the age of 30 days only. The segments contained a reduced number of axial microtubuli and contacted microvilli of supporting cells. The pattern and ultrastructure of olfactory cells of an adult sheep did not differ from those of a 30-day-old lamb. Degenerating olfactory cells were observed only sporadically. Supranuclear cytoplasm of supporting cells contained glycogen inclusions and bundles of tonofibrils. Sense organs, transmission electron microscopy, olfactory epithelium, ontogenesis

Kociánová I., F. Tich˘, A. Goro‰ová: Ultrastructure of the Olfactory Epithelium of Kittens. Acta Vet. Brno 2001, 70: 375-379.The structure of the olfactory epithelium of a 35-to-40-day-old kitten was studied by transmission electron microscopy. The samples were collected from the ethmoidal labyrinth. At this stage of development, the regio olfactoria was lined by a typical pseudostratified olfactory epithelium built of olfactory cells, sustentacular cells, and basal cells. The height of the epithelium varied between 16 and 18 µm. A characteristic feature of the free surface of the epithelium was a considerable degree of differentiation. Protruding above the surface were endings of dendritic projections of sensory cells with a diameter of 0.8-to-1.0 µm carrying numerous atypical cilia and 1.0-to-1.5 µm long microvilli of sustentacular cells. Supranuclear segments of the supportive and olfactory cells contained a large amount of rough and smooth endoplasmic reticulum and numerous elongated mitochondria. Long dendritic projections of the olfactory cells were closely surrounded by apical cytoplasm of the sustentacular cells. Contacts among the cells were provided by close intercellular links. The data on the structure of the olfactory epithelium of 35-to-40-day-old kittens indicate that the epithelium at this age is fully functional. Sense organs, transmission electron microscopy, olfactory epithelium, ontogenesis

Gorošová A., E. Matalová, I. Kociánová, F. Tichý: Langerhans Cells in Feline Foetal Epidermis -Immunohistochemical Study of Spatial Distribution. Acta Vet. Brno 2008, 77: 307-312. Langerhans cells belong to the skin-associated lymphatic tissue (SALT). They are antigenpresenting cells derived from monocyte precursors in the bone marrow.The distribution of Langerhans cells was investigated in feline foetuses on day 40 of ontogenesis, in 9 selected body regions: regio intermandibularis, regio axilaris, regio prepubica, regio inguinalis, regio parietalis, regio interdigitalis, regio thoracis, regio sacralis and regio caudalis. Mouse monoclonal antibody against CD1 receptor (epitope CD1a) was applied to localize Langerhans cells in the skin samples.The highest number of Langerhans cells was found in biopsy of the dorsal part of the feline foetuses. Langerhans cells were present particularly among keratinocytes of stratum germinativum (stratum basale and stratum spinosum), scattered or clustered among epidermal cells closing the hair canal in the region close to the hair follicle. Langerhans cells were further located among cells of outer root sheath in the region of hair follicle infundibulum close to ostium of sebaceous glands ductus, some were found also in the upper part of the hair follicle isthmus.Langerhans cells seem to participate in skin disorders related to hypersensitivity and even tumour transformations. Distribution of these cells may play a role in disease predispositions; knowledge of the physiology and pathophysiology of Langerhans cells opens possible targeted treatments in veterinary medicine. Skin, cat foetus, SALT, CD1In general, skin represents an important anatomical and physiological barrier but also a communication means between organisms and their external environment. Moreover, skin is an integral part of the immune system. Different cell types present in the skin such as Langerhans cells (LC), dermal dendritic cells, epidermotropic T-lymphocytes together with skin draining lymph nodes belong to an integrated tissue system mediating skin immune protection and forming so called skin-associated lymphoid tissue (SALT) (Streilein et al. 1999).Both innate and acquired immunity operate in close relationship open exposure of the skin to various antigens. LC stimulate proliferation of important T-helper lymphocytes by antigen presentation on their surface, thus inducing also cytotoxic T-lymphocytes to moderate the allogeneic reaction. LC produce interleukin 1 and other cytokines, moreover, they are capable of phagocytosis and contain many different enzymes (Goodell et al. 1985).LC stem cells originate from pluripotent hematopoietic progenitor cells CD34+ in the bone marrow. Recent results identified monocytes with a high expression of Gr-1(Ly-6c/G) marker as the direct precursors for LC in vivo and showed the importance of the colony-

Abstract