In June 2015, a highly fatal and acute disease broke out in a duckling farm in Hyogo Prefecture, Japan. The birds exhibited poor growth, reduced movement, lying in a dorsal recumbent position, depression, lethargy, ataxia and opisthotonus, with a high mortality rate of approximately 76%. By performing a reverse transcription-polymerase chain reaction (RT-PCR) using primers specific for duck hepatitis A virus type 1 (DHAV-1), we obtained the PCR products of a predicted size. The nucleotide sequences of the PCR products showed a >96% identity with that of the DHAV-1, HB02 strain, which was isolated in China. To our knowledge, this is the first time that the DHAV-1 virus has been isolated since its outbreak in Japan in 1963.

ABSTRACT. A melanotic neurofibroma in a steer was investigated histologically, immunohistochemically and ultrastructurally. A very large tumor mass was located in the region of the head and right cheek. The tumor tissue consisted of an admixture of cells resembling Schwann cells and spindle-shaped cells, and they frequently contained melanin granules. Neoplastic Schwann cells were positive for S100 protein, with variation in intensity of staining, but most spindled cells were S100 negative. The tumor cells displayed ultrastructural features similar to those of Schwann cells or perineurial cells. The presence of melanosomes in varying stages of melanization in both cell types suggests that they have a common origin. This is a tumor of neural crest origin showing schwannian and perineurial differentiation, with ectopic production of melanin granules.-KEY WORDS: bovine, melanotic neurofibroma, S100 protein.

Abstract.A diagnosis of plasma cell myeloma was made in a 6-year-old Holstein cow that showed continuous nosebleed, progressing emaciation, and hyperglobulinemia. Necropsy revealed enlargement of the caudal mesenteric lymph nodes. Lymph nodes and spleen were infiltrated by neoplastic plasma cells. Renal lymph nodes, bone marrow, and kidneys also were affected. Amyloid-like material that was negative for Congo red was present in most of the affected lymph nodes. Congo red-positive amyloid material was noted in spleen, kidneys, liver, and adrenal glands. Neoplastic plasma cells exhibited immunohistochemical reactions for -light chain and 3 classes of heavy chain but not for -light chain. Nonamyloid deposits were labeled with antisera against -light chain and heavy chains. Plasmacytoid cells, which stained positively for IgG, IgM, or IgA, were intermingled in all lesions. Production of 3 types of immunoglobulins may be caused by heavy-chain class switching, constantly occurring in certain proportions.Plasma cells are a differentiated form of B lymphocytes and actively synthesize immunoglobulin. Plasma cell myeloma (multiple myeloma) or plasmacytoma is a neoplastic proliferation of plasma cells. 1 Most human myelomas secrete complete immunoglobulin molecules of a single heavy-chain and light-chain type, indicating monoclonality. Two or more monoclonal proteins have been found in a small number of cases. 5 Production of 2 types of heavy-chain immunoglobulin molecules has been demonstrated in swine lymphomas including a plasmacytoma. 7,8,16 Two forms of immunoglobulin tissue deposition, AL amyloidosis and nonamyloid immunoglobulin deposition disease, occur in humans with multiple myeloma. 3 Amyloidosis associated with plasma cell tumors has been reported in dogs, cats, 13 and horses. 2 Plasmacytic neoplasms in ruminants are rare. 11,12 This report is a description of a case of bovine plasma cell myeloma characterized by the production of 3 types of immunoglobulins, and amyloid and nonamyloid immunoglobulin deposition.Five months after fourth parity, a 6-year-old Holstein cow exhibited epistaxis, anorexia, depression, and a rectal temperature of 39.0 C. Body condition continued to deteriorate with rapidly progressing emaciation. The cow was euthanatized 1 month after the onset of clinical signs. Before euthanatization, blood evaluation showed anemia (red blood cell count, 3.3 ϫ 10 6 /l; normal range, 5.0-10.0 ϫ 10 6 /l; hematocrit, 14.0%; normal range, 24.0-46.0), and the white blood cell count was 11,800/l (normal range, 4,000-12,000/l). Total protein and albumin concentrations in serum were 7.70 g/dl (normal range, 6.55-7.65 g/ From Himeji Livestock Hygiene Service Center, 2-10-16 Taderahigashi, Himeji 670-0081, Japan (Kameyama), and Hokkaido Research Station, National Institute of Animal Health, 4 Hitsujigaoka, Toyohira, Sapporo 062-0045, Japan (Ishikawa, Shibahara, Kadota). dl) and 1.10 g/dl (normal range, 3.15-3.85 g/dl), respectively. Serum electrophoresis produced a biclonal peak in the gammaglobulin fraction ac...

ABSTRACT. Establishment of a disposal plan for carcasses in advance is important for prevention of epidemics. A disposal plan for contaminated goods such as poultry carcasses infected with highly pathogenic avian influenza (HPAI) virus was studied in Hyogo Prefecture, Japan. We investigated all poultry farms with over 1,000 birds for their locations, species and numbers of birds, structure and size of poultry facilities and land spaces of the farms. Moreover, we judged whether they could dispose of all the carcasses at their farms. In 2005, 5.5 million layers and 2.7 million broilers were being kept. If HPAI had broken out, 44.0% of the farmers could bury all the carcasses, and 65.6% could compost them at their farms. However, 23.4% could not dispose of them except by burning them at incineration facilities. We decided to choose burning first for rapid disposal as long as the virus was not a pandemic type.KEY WORDS: avian disease, epidemiology, influenza.

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