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White tail disease (WTD) is a serious problem in Macrobrachium rosenbergii hatcheries and nursery ponds in Asia. The causative agents have been identified as M. rosenbergii nodavirus ( MrNV) and its associated extra small virus. This is the first report demonstrating MrNV virus in M. rosenbergii displaying WTD signs in Taiwan by reverse transcriptase-polymerase chain reaction (RT-PCR). Amplified fragments of 850 and 425 bp for RNA-1 and RNA-2 of MrNV, respectively, were obtained by RT-PCR. RT-PCR products of about 850 and 1121 bp for RNA-1 and RNA-2 of MrNV were also obtained using different primer pairs. The amplicons were individually cloned into pGEM-T vector and sequenced. Using this recombinant plasmid of MrNV RNA-2 as DNA template, the non-radioactive DNA probes were prepared by PCR amplification with DIG–11-dUTP. The probes were used to successfully detect MrNV infection in the striated muscle tissues of WTD-diseased prawns using in situ hybridization. The 1121 bp genomic fragment of RNA-2 of MrNV consisted of a unique open reading frame with 1116 nucleotides, and it encoded a structural protein with 371 amino acids. The nucleotide sequence of the partial genome of MrNV RNA-2 revealed a 97% identity with an Indian isolate. A phylogenetic tree constructed using the nucleotide sequence of the viral capsid gene from insect and fish nodaviruses revealed that the MrNV Taiwan isolate could be interpreted as a new genus within the family Nodaviridae. However, its position showed more affinity with Alphanodavirus than with Betanodavirus. The study confirmed the presence of MrNV infection in freshwater prawns cultured in Taiwan suffering from WTD. [ABSTRACT FROM AUTHOR]

Post-larvae of Macrobrachium rosenbergii infected with white tail disease (WTD) have been reported in Taiwan. The causative agents have been identified as M. rosenbergii nodavirus ( MrNV) associated with extra small virus (XSV). The present study is the first report confirming the presence of XSV virus in M. rosenbergii displaying WTD symptoms in Taiwan by reverse transcription polymerase chain reaction (RT-PCR). A 772 bp amplified product was obtained by RT-PCR, cloned and sequenced. The nucleotide sequence analysis of the 772 bp DNA fragment revealed 98% and 97% identity with XSV isolated from China and India, respectively. Comparison of the deduced amino acid sequences of the XSV partial genome showed strong homology (99% and 97%) with isolates from China and India. Phylogenetic analysis revealed the XSV-Taiwan isolate was more closely related to the Chinese rather than the Indian isolates. The results demonstrated the presence of XSV virus co-infection in M. rosenbergii cultured in Taiwan suffering from WTD. [ABSTRACT FROM AUTHOR]

Presents the histological study of Macrobrachium muscle virus (MMV) infection on cultured freshwater prawn, Macrobrachium rosenbergii in Taiwan. Use of transmission electron microscope in assessing the outbreaks of the disease; Histopathological changes of the disease; Feature and structure of the infected freshwater prawn.

The development of Caligus multispinosus was studied using instars reared from eggs in the laboratory and specimens obtained from the gills of pond-cultured black sea bream. Nine stages were identified, namely, two nauplii, one copepodid, four chalimus stages, one preadult and the adult. The distinctive feature of the spinulose outer spines on leg 4 appeared late in development (preadult stage) and the frontal filament produced in chalimus I is kept throughout the chalimus stages. [ABSTRACT FROM AUTHOR]

Since 1993, an epizootic viral disease has occurred in net-cage cultured red sea bream, Pagrus major (Temminck & Schlegel), in Peng-hu Island located on the south-western coast of Taiwan. The diseased fish exhibited abnormal swimming and were lethargic, but few visible external signs were observed. The cumulative mortality because of the disease sometimes reached 50-90% over 2 months. Histopathogical studies of the affected fish showed enlarged basophilic cells in the gill, kidney, heart, liver and spleen. These necrotic cells were Feulgen-positive and stained blue using Giemsa. Transmission electron microscopy revealed icosahedral virions in the cytoplasm of the necrotic cells. The viral particles consisted of a central nucleocapsid (75-80 nm) and envelope, and were 120-150 nm in diameter. These results suggest that the virus belongs to the Iridoviridae. Using polymerase chain reaction (PCR), approximately 570 bp fragments were produced from the viral DNA using as a template 1-F and 1-R primers derived from red seabream iridovirus (RSIV) from red sea bream in Japan. Similar results were also obtained using nested-PCR with different primer sets (1-F, 2-R and 2-F, 1-R). Although the size and some features of epizootics of this virus differed from RSIV in Japan, it shows close genetic affinities with the latter and it is suggested that RSIV has been introduced to Taiwan.

Six species of copepods of the genus Caligus (Caligidae, Siphonostomatoida) parasitic on marine fishes of Taiwan are reported. They are: C. absens n. sp. from Priacanthus blochii and P. macracanthus; C. epinepheli Yamaguti, 1936 from Scolopsis vosmeri; C. kanagurta Pillai, 1961 from Decrapterts kurroides; C. laticaudus Shiino, 1960 from Lutjanus vitta and Parapristiopoma trilineatum; C. nengai Rangnekar, Rangnekar & Murti, 1953 from Triacanthus biaculeatus; and C. rotundigenitalis Yü, 1933 from Drepane punctata, Liza macrolepis and Terapon jarbua. C. distortus Pillai & Natarajan, 1977 is relegated to a synonym of C. nengai and C. multispinosus Shen, 1957 reported by Lin et al. (1994) from the cultured sea bream Acanthopagrus schlegeli is a misidentification for C. rotundigenitalis Yü, 1933.

Tzu Chi Taiwan Marrow Donor Registry (TCTMDR) was established in 1993 to recruit and HLA-type volunteers who would be willing to donate bone marrow. TCTMDR is currently the largest marrow registry for Chinese in the world, with over 150,000 prospective donors registered as of July 1997. We present here the gene and haplotype frequencies based on 80,353 HLA class I-typed and 18,217 HLA class II-typed healthy Chinese in Taiwan. The resulting frequencies are used for estimating the probability of finding an HLA-matched donor for a patient. The common HLA class I antigens include A1 (gene frequency: 32.9%), A2 (29.7%), A24 (17.5%) and A33 (11.0%); B60 (18.1%), B46 (12.8%), B58 (9.8%) and B13 (7.8%); Cw3 (51.4%), Cw1 (11.6%) and Cw7 (8.6%). The common HLA class II antigens are DR4 (16.6%), DR9 (15.6%), and DR12 (14.0%); DQ7 (20.7%), DQ9 (12.7%), and DQ5 (12.1%). The common two-locus haplotypes observed with a P-value less than 0.001 are A2-B46 (haplotype frequency: 8.5%), A33-B58 (7.5%), A11-B60 (6.6%); B58-DR17 (7.0%), B46-DR9 (6.4%) and B60-DR4 (4.9%). The common three-locus haplotypes are A33-B58-DR17 (5.3%), A2-B46-DR9 (3.9%) and A11-B60-DR4 (2.0%). As expected, the gene frequency pattern of Taiwanese is more closely related to that of southern Hans than to the pattern of northern Hans, Japanese, Caucasians and African-Americans. Using our registry, 323 of 571 domestic patients (57%) successfully identified one or more matched donors. The empirical result correlated well with a mathematical simulation having an estimated 59% match when donor pool reaches 150,000.

Outbreaks of high mortality among the cultured kuruma prawn Penaeus japonicus without overt gross signs occurred during August and December of 1994 in I-Lan, Taiwan. Eleven luminous bacterial strains were isolated from the hepatopancreas of moribund prawns from five different farms by use of tryptic soy agar (TSA, supplemented with 2% NaCl) and/or thiosulfate citrate bile salt sucrose (TCBS) agar. These strains, together with our two previously unpublished isolates, were characterized and identified to be Vibrio harveyi in comparison with two ATCC Type strains and one strain previously isolated from the tiger prawn, P. monodon.

Analysis of the neonatal mortality record at the neonatal unit of Changhua Christian Hospital for the five-year period from 1989 to 1993 (period 2) is presented and compared with that of the period 1979-1983 (period 1). This retrospective study is to evaluate whether the mortality rate and causes of neonatal death are affected by the changing perinatal care environment in Changhua area. This study shows that the mortality rate of the all admitted babies was dramatically decreased in period 2 (18% vs 12.35%, P < 0.01) and the mortality rate of delivered babies in our hospital was significantly decreased in period 2, too. (32.74% vs 11.61%, P < 0.001). However, the mortality rate of the babies referred from other hospitals was not different between the two periods (12.30% vs 12.72%, P > 0.05). These results can be explained by the higher quality of prenatal and delivery care, higher standard of neonatal intensive care for the sick neonates in period 2 and a comprehensive transport system which was established in 1987. RDS, prematurity, sepsis, asphyxia (particularly MAS with PPHN) and congenital malformations were still the main causes of neonatal death in period 2. We suggested that prevention, early diagnosis and intervention of these disorders and regionalization of perinatal care with a more comprehensive transport system are mandatory in Changhua area.

The large number of hemocytes infiltrated several abnormal tissues of kuruma shrimp (Penaeus japonicus), including musculature, hepatopancreas, lymphoid organ, gill filament and sponge tissue. In addition, there were many denatured hemocytes existing inside acidophilic particles and forming granules. Futhermore, in hepatopancreas of kuruma shrimp, a white spot baculovirus (WSBV; 40-50 x 50-300 nm) was discovered in UH (undifferential haemocyte). The epithelium cells, which including stomach cuticle and underlying epidermis of exoskeletal cuticle, could also be infected by WSBV in another main cultural species--grass shrimp (P. monodon). During a period of high water temperature, with pond shrimp in normal condition, the CFU/ml of water bacteria rose from 10(5) to 10(7), but this number had decreased to 10(5) CFU/ml by the time moribund shrimp began to appear. Coincidentally, the total bacterial number isolated from hepatopancreas and musculature of moribound shrimp was over 10(5) (CFU/g) and 10(3)-10(5), respectively. The fauna of bacteria was taken over by the active metabolitic species which were represented by Vibrio species causing the pond shrimp to undergo either behavioral changes, such as swimming on the water surface, or histological changes, such as having whitish muscle color, hemocyte infiltration and granuloma formation etc. Pathogenetic species of Vibrio including V. parahaemolyticus, V. alginoly ticus V. anguillarum, V. fischery and V. damsela were isolated from those tissues of moribund shrimp. The main pathogens, isolated from musculature and hepatopancreas, were V. parahaemolyticus and V. alginolyticus. On the other hand there, was no bacterium could be isolated from the musculature of healthy shrimp and only a single species of Gram (+) coccus--Micrococcus--was isolated from the tissue of hepatopancreas.