Two 1-year-old Korean native steers in the same herd presented severe hemorrhagic diarrhea. Case 1 had severe dehydration and died after 3 days, whereas case 2 had anorexia, depression, and severe diarrhea with mucus and blood. Only case 2 was necropsied, and bovine viral diarrhea virus-2a (BVDV2a) was detected in the tissues of its alimentary tract. Gross lesions, including erosion, ulceration, and extensive hemorrhage, were observed in the digestive tract mucosa. Immunohistochemistry revealed marked positive staining for BVDV2a antigen in the large intestine. These findings are indicative of hemorrhagic disease caused by BVDV2a in a native Korean steer.

We describe 7 cases of splenic smooth muscle tumors in dogs. Histopathological and immunohistochemical analysis revealed that 6 cases were diagnosed as splenic leiomyosarcoma and 1 case as leiomyoma. All dogs underwent splenectomy without chemotherapy, and one of them was euthanized 2 months after surgery because of hepatic metastasis. Of the remaining 6 dogs, 5 died in the postoperative period and only one dog survived > 4 years. The median survival of the 6 dogs was 16.9 months. To the best of our knowledge, this is the first detailed study on splenic smooth muscle tumors in dogs in Korea.

Peripheral nerve sheath tumors (PNSTs) are heterogeneous tumor groups of peripheral nerves that originate from either Schwann cells or modified Schwann cells, fibroblasts, or perineural cells. In this study, signalment and clinical data such as tumor location and size were evaluated for 15 cases of PNSTs collected from local animal hospitals. The mean age of dogs with malignant PNST was higher than that of dogs with benign PNST. Additionally, the male to female ratio in dogs with PNST was 1 : 4. In dogs with PNST, the primary sites of involvement were the hindlimb, forelimb, around the mammary glands, the neck, and the abdomen. Histiopathologic examination revealed that eight PNSTs were benign and seven were malignant. The tumor cells were composed of loosely to densely arranged interlacing bundles and wavy spindle cells arranged in short bundles, palisading, and whirling. High mitotic figures, local invasion, multifocal necrosis and atypical multinucleated giant cells were observed in malignant PNST cases. All PNSTs showed immunoreactivity for vimentin and S-100. However, only 93.3% and 73.3% were immunoreactive for NSE and GFAP, respectively. Overall, these results indicated that immunohistochemical markers such as vimentin, S-100 and NSE could help confirm the diagnosis of canine PNSTs.

The obligatory intracellular protozoan parasite Toxoplasma gondii is a major world wide cause of infectious ovine abortion. In some different diagnostic techniques that are being used to detect this pathogen in ovine fetuses, immunohistochemistry (IHC) is a very sensitive and expensive one. Histopathology is not truly a specific and sensitive test for Toxoplasma infection but it can be helpful to choose some suspected tissues for IHC. In this study 9.5% of 200 samples (aborted ovine fetuses internal organs such as brain, liver, heart, lung, kidney, spleen) (4.6~14.4% with 95% CI) were positive in IHC with a very good logical agreement among different diagnostic techniques (κ = 0.73, 0.8) and with no significant difference among different fetal age groups (p 0.05).

The vomeronasal organ (VNO) plays an important role in reproduction and social activities in ruminants including goats. A morphological study on the structure of VNO and its epithelial cells was carried out in Korean black goats. Grossly, the VNO of Korean goats opens into mouth through incisive ducts. Microscopically, the epithelium of VNO consisted of medial sensory epithelium and lateral non-sensory epithelium. Several blood vessels and nerve bundles were observed in the lamina propria encased by vomeronasal cartilage. Immunohistochemical staining showed that protein gene product (PGP) 9.5 was immunostained in the receptor cells of the sensory epithelium and in some cells of the non-sensory epithelium. Galectin-3 was mainly observed in the supporting cells of sensory and non-sensory epithelium. Lectins including wheat germ agglutinin, Ulex europaeus agglutinin, Bandeiraea simplicifolia lectin Isolectin B4, Dolichos biflorus agglutinin and soybean agglutinin used in this study were bound in VNO sensory, non-sensory epithelia as well as in the lamina propria with varying intensity. Collectively, this is a first descriptive morphological study of VNO of Korean black goat with special reference to lectin histochemistry.

In the present study, we investigated the expression patterns of ErbB family proteins in the pre-pubertal and pubertal mammary glands of dairy cows in association with gland development. For this study, we performed immunohistochemistry for ErbB-1-4 and Ki-67 cell proliferation marker. We found that the pre-pubertal and pubertal mammary glands had typical structures, including ducts and terminal end buds embedded in the stroma, and no development of lobuloalveolar structures. On immunohistochemistry, ErbB-2 and ErbB-3 were strongly expressed in the cytoplasm and nuclei in the epithelial cells of mammary ducts and terminal end buds, and stromal cells, whereas ErbB-1 and ErbB-4 were weakly expressed only in the cytoplasm of gland epithelium and stromal cells, irrespective of the developmental stage. Cell proliferation was inactive in the mammary gland cell compartments in both phases. Thus, expression of the ErbB family in the developing mammary glands was not associated with their functional effects, such as cell proliferation and lobuloalveolar development. In conclusion, ErbB receptors were differentially expressed in the epithelial and stromal cells of virgin mammary glands of dairy cows. Compared with rodent mammary glands, ErbB-3 and ErbB-4 were found to be highly expressed in bovine mammary glands.

In this study, immunohistochemistry was used to examine the changes in the density of colonic endocrine cells - argyrophil and argentaffin cells, chromogranin A (CGA), serotonin, somatostatin and glucagon-containing cells in trinitrobenzene sulfonic acid (TNBS)-induced rat colitis. Ulcerative colitis was induced by the instillation of 10 mg of TNBS into the colonic lumen through the anus. To confirm the inducement of ulcerative colitis, the macroscopic and microscopic scores as well as the colonic myeloperoxidase (MPO) activities were monitored for 8 days after TNBS instillation in the colonic lumens. In addition, the number of argyrophil and argentaffin cells, CGA, serotonin, somatostatin and glucagon-immunoreactive cells were counted in the colonic mucosa, respectively. After TNBS instillation into the lumen of the colon from the anus in rats, increases in macroscopic and microscopic scores in the colon tissues were observed along with increases in the colonic MPO activities. Therefore, ulcerative colitis was relatively well induced by the TNBS instillations. Marked decreases in the number of colonic endocrine cells were detected in the TNBS-treated animal compared to the sham control. These results suggest that colonic endocrine cells were also disrupted by TNBS-induced ulcerative colitis.

Postweaning multisystemic wasting syndrome (PMWS), which was first identified in western Canada in 1991 and more recently in the United States, Europe and Asia, is an emerging disease in pigs. Porcine circovirus type 2 (PCV-2) is the primary infectious viral agent causing PMWS, but the full expression of the disease may require the presence of other agents. It is reported that there is apparent synergism between PCV-2 and porcine parvovirus (PPV) in increasing the severity of the clinical signs and lesions of PMWS. From January 2006 to May 2008, a total of the 154 lymph node samples were collected from 4~12 weeks old pigs which had been submitted to the College of Veterinary Medicine, Jeju National University, Korea. These pigs were diagnosed as PMWS on the basis of clinical and pathological examination from 48 commercial herds in Jeju Island. Based on the immunohistochemistry, porcine parvovirus was detected in 69 cases (44.8%) from 154 weaned or grower pigs. PPV antigens were detected in the cytoplasm of histiocytic cells multifocally infiltrated in the cortex and paracortex of lymph nodes. The results of this study clarify that PPV is prevalent in pigs with PMWS on Jeju Island. Therefore PPV is one of the most important co-agents in the development of naturally acquired PMWS. This study may be helpful to the control of this disease and to epidemiological aspects.

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 10-year-old female Yorkshire terrier with the clinical signs of nasal swelling, epistaxis and nasal discharge was presented to the Veterinary Teaching Hospital in the Cheju National University. Abnormal nasal mass detected in physical examination and radiographic findings. After surgical excision, the sample of nasal mass was referred to Pathology Department of Veterinary Medicine. Grossly, the mass was soft, friable, and 2.5 × 4 cm in size. Histopathologically, the mass was composed of medium-sized non-keratinizing columnar to polyhedral cells arranged in anastomosing ribbon and large nest. It has complex in-folding of thick epithelial layers separated by fibrovascular septa. Tumor cells showed characteristic palisading arrangement of columnar cells, and perpendicularly distributed to the basement membrane. The cells had pale basophilic cytoplasm, oval nucleus and one or more nucleoli, and indistinct cellular border. Many tumor cell emboli were presented in lymphatics. Immunohistochemistry revealed that tumor cells were cytokeratic (CK) 19 and CK clone MNF116 positive and but CK7 and CK high molecular weight negative. Based on the gross, histopathologic, and immunohistochemical findings, the mass was diagnosed as transitional carcinoma in nasal cavity. In our best knowledge, this is the first report of transitional carcinoma originated from transitional zone of canine nasal cavity in Korea.