Transcutaneous oxygen (PO2.TC) monitoring is commonly used in human medicine for evaluating skin viability. The application of transcutaneous monitoring for evaluating skin viability in dogs was investigated. The changes in PO2-TC values were measured from 16 avascular skin flaps created along the lateral hemithoraces of 4 dogs. Transcutaneous oxygen values were serially recorded from the vascular base and avascular apex of each flap for 12 hours after surgery. A single transcutaneous measurement was obtained from each flap base and apex 24 hours after surgery. Serial arterial blood gas analyses were obtained to compare central oxygen values with PO2-TC values. Full-thickness skin biopsy specimens were harvested from the base and apex of each flap 24 hours after surgery. The flaps were observed for 4 days and then excised for histologic examination. A subjective grading scale was used to assess histologic changes. Throughout the 12-hour period and at 24 hours, a statistically significant difference was found between the PO2-TC values for apices and bases of the flaps. The mean PO2-TC for all bases was 90.9 mm of Hg +/- 3.3 SEM, and the mean PO2-TC for all apices was 21.2 mm of Hg +/- 1.8 SEM. The mean regional perfusion index (apex PO2.TC/base PO2-TC) was 0.23 +/- 0.02. The subjective numbers assigned to the biopsy specimens were statistically evaluated by using a paired Student's t test and a Wilcoxon signed-rank test. A significant difference was found between the numbers for the collective bases and apices with both tests. A statistically significant difference was found between the numbers for the apex biopsy specimens taken 24 hours after creation of the skin flap and those taken when the flap was excised, whereas no difference was found between the numbers for the base biopsy specimens. On the basis of our findings, PO2-TC monitoring is a useful technique for assessing skin viability in dogs.

The area of skin supplied by the afferent fibers in one cutaneous nerve is called the cutaneous area (CA) for that nerve. The CA of peripheral branches of lumbar and sacral spinal nerves responsive to the stimulation of hair follicle mechanoreceptors were mapped in 27 dogs. The amount of overlap among the CA was similar to that found for other CA of the body. The CA of peripheral branches of the sciatic nerve were restricted to the lateral, cranial, and caudal aspects of the pelvic limb distal to the stifle. The CA of the saphenous nerve was located on the medial side of the limb, except for a small area located on the lateral side of the crus. The distal part of the CA of the saphenous nerve was completely overlapped in the hind paw by branches of the superficial peroneal nerve laterally and the medial plantar branch of the tibial nerve medially. The CA for the deep peroneal nerve was located on the dorsal surface of the webbing between digits 2 and 3 and the adjacent skin of these digits. The CA of the plantar branches of the tibial nerve were small in comparison with the diameter of the nerve, suggesting that these branches contained nerve fibers supplying other, deeper structures in the hindpaw and that damage to these nerves would interfere with cutaneous sensation in only a small region on the plantar surface of the hindpaw. Knowledge of the CA of the various branches of the sciatic nerve allows more accurate localization of injury to the sciatic nerve or its branches by using areas of anesthesia.

Cell proliferation kinetic values were established for the epidermis, hair follicle epithelium, and sebaceous glands of 8 Cocker Spaniels with primary idiopathic seborrhea. Values were established by intradermal pulse labeling injections of tritiated thymidine followed by cutaneous biopsy and autoradiography.The epidermal basal cell-labeling index was 4.96 +/- 0.97%, and the epidermal nucleated cell-labeling index was 3.33 +/- 0.71%. Calculated epidermal cell renewal time for the viable layers of the epidermis was 7.85 +/- 1.80 days. The hair follicle infundibulum basal cell-labeling index was 5.48 +/- 2.01%, and the sebaceous gland basal cell-labeling index was 5.94 +/- 4.15%. When compared with previously reported cell kinetic values for Cocker Spaniels and Beagles with healthy skin, these data indicate accelerated cellular proliferation in all 3 cutaneous structures in seborrheic Cocker Spaniels.

A study was undertaken to determine the pressor and toxic effects of etoposide, an antineoplastic agent, when administered IV in 0.9% sodium chloride solution (0.4 mg of etoposide/ml) over a 30-minute period to dogs at a dosage of 40 mg/m2 of body surface. On day 1, 6 adult German Shorthaired Pointers were anesthetized with halothane, and blood pressures were measured via a femoral artery catheter before, during, and after the etoposide was administered. Systolic, diastolic, and mean blood pressures of each dog increased significantly (P less than 0.01) within 30 minutes after initiation of etoposide infusion. On day 3, when the dogs were not anesthetized, etoposide was again administered to each dog, using the same dosage. Each dog developed a moderate to severe cutaneous reaction characterized by moderate to severe pruritus, urticaria, and swelling of the head and extremities that began during the second infusion of etoposide. These same cutaneous reactions were seen on day 30, when etoposide was administered to 3 of the previously treated dogs and 2 previously untreated Beagles. We concluded that the administration of the commercial preparation of etoposide is likely to cause a significant reduction in blood pressure of anesthetized dogs, and that the drug is likely to induce a moderate to severe cutaneous reaction when administered to unanesthetized dogs.

Cutaneous leiomyomas (leiomyosarcomas) are smooth muscle tumors that occur single or as multiple lesions. They usually arise from the arrector pili muscles (piloleiomyomas) and less commonly from the muscle of veins (angioleiomyomas). This report describes histologic and immunohistochemical features of one cutaneous piloleiomyoma and two angioleiomyosarcomas. Three 7-12-year-old female dogs were presented with single or double cutaneous nodules. Histologically, the neoplastic masses were composed of densely or loosely arranged interlacing bundles. The neoplastic cells were ovoid to elongate, and had eosinophilic cytoplasms and perinuclear cytoplasmic vacuolation. Nuclei were central to eccentric, cigar shaped, oval to elongate. In two cases high mitotic index in high power field, multifocal necrosis and local invasion were also noted. Masson's trichrome and van Gieson staining revealed muscle origin tumors in these cases. Immunohistochemically, the tumor cells were strongly positive for smooth muscle actin. In our best knowledge, this is the first report of cutaneous smooth muscle tumors in dogs in Korea.

A 7-month-old brown pig with a discoid and pedunculate mass measuring 14.0×12.5×2.5 cm on the skin of the right shoulder was noted at the slaughter house in Jeju. The surface of mass approximately 7×4 cm was interfaced with skin. The color of mass with firm consistency was mainly black and partially white on cut surface. Histopathologically, numerous unencapsulated endocrine-like cellular nodules of epithelioid cell type with abundant intracytoplasmic black pigment, melanin, were occupied in dermis and subcutis.

In this study, we describe a case of epitheliogenesis imperfecta (EI) observed in the fetus of Korean native cattle. The fetus had multifocal areas of skin defect, especially on the distal portions of the four limbs, and the affected areas were bright-red and glistening. Histopathologically, these areas were characterized by complete absence of squamous epithelium, infiltration of inflammatory cells into the dermis, atrophy of hair follicles, sebaceous and sweat glands. To the best of our knowledge, this is the first report of epitheliogenesis imperfecta in Korean native cattle.

The purpose of the present study was to investigate the effect of bovine amniotic membrane grafts on healing of full-thickness skin wound in dogs. Two 3cm*3cm area-matched full-thickness skin wounds were induced bilaterally on the dorsolateral aspect of the trunk of 15 dogs Chlorhexidine-treated amnion, dried amnion, silver sulfadiazine and 0.9% sterile saline solution were applied on the wound area and examined grossly and histopathologically. Begining 14 days after wounding, amnion applied group had appreciably less amount of inflammatory exudate and hemorrhage than sulfadiazine and saline treated groups. From 14 days after wounding, the degree of wound contraction in amnion groups, especially in the dried amnion group was greater than that of the sulfadiazine and saline treated groups. The percentages of wounds completely healed on 28 days after wounding in saline treated group, chlorhexidine-treated amnion group, dried amnion group and sulfadiazine treated group were 33%, 50%, 83% and 50%, respectively. Microscopically neovascularization and fibrosis were first noticed on 5 days after wounding in the dried amnion group and sulfadiazie treated group, on 7 days in the chlorhexidine-treated amnion group and on 14 days in the saline treated group. Epithlialization in thedried amion and sulfadizine treated groups ws first noticed on 9 days after wounding, which was faster than that in the other groups. The present study suggests that bovine amniotic membrane, especially dried bovine amnion is effective on healing of full-thickness skin wound in dogs through both wound contraction and epithelialization.