摘要:

Abstract.Ultrastructural observations on a possible aetiological agent and tissue changes in a previously described disease of hatchery reared larval oystersCrassostrea gigasThünberg are reported. Spherical bodies, implicated in gastro‐intestinal impaction, show a strong resemblance to the marine fungus,Hyalochlorella marina. Similarities include a thick outer wall structure, plate‐like mitochondria and dense cytoplasm with small vacuoles.The dense fascicular masses, previously observed histologically at epithelial surfaces, consist of accumulations of irregular electron opaque bodies. Large accumulations of these bodies appear to exacerbate tissue damage and prevent normal velar function. In comparison with the reported virus‐like particles in this disease, these dense inclusions and associated lesions are more frequently observed and thus seem to be more important in the disease process.Notes on normal epithelial surfaces of larvalCrassostreaspp. are in

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1980.tb00178.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Abstract.Sphaerospora angulataFujita, 1912, has been identified as a frequent renal parasite of cultured carp populations in Hungary. Its prevalence ranged from 10 to 50% in the pond farms surveyed. The youngest carp infected were 21/2–3 months old. Infections were not common in one‐summer fish and tended to become less frequent with increasing age of the host.The developing stages ofS. angulataare found in the contorted tubules of the trunk‐kidney but never invade the parenchymal tissue of the trunk or head‐kidneys. The pansporoblasts developing in the wide proximal segment of the renal tubules, and the spores arising from the pansporoblasts are typically coelozoic parasites, for they apparently do not damage the tubular lining epithelium, nor its brush border. The main adverse effect ofS. angulatais probably depression of resistance owing partly to deprivation of the host of nutrients secreted by the glomeruli and partly to mechanical obstruction of the distal tubular s

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1980.tb00179.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Abstract.Viral haemorrhagic septicaemia (VHS) is reported for the first time in sea‐water cultured rainbow trout. Heavy mortalities with typical signs and lesions A VHS virus (serotype 1) was isolated from the diseased fish. The mortalities were caused only by the VHS virus and 80 days post transfer of trout to sea‐water the mortalities reached 85%, of the initial population.The disease was experimentally transmitted to rainbow trout, both in sea‐water 3·104pfu/ml of virus or by intramuscular injection of various doses of VHS1(7·1017·104or 7·104pfu per fish). Death occurred in all infected groups and started earlier in sea‐water. Typical signs of VHS were observed in moribund fish. Viral multiplication was demonstrated to have occurred in

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1980.tb00180.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Abstract.Blood spots in the eye and haemorrhages in the musculature of the caudal peduncle were the main indication of disease in Australian hatchery reared brook troutSalvelinus fontinalis(Mitchill) and Atlantic salmonSalmo salarL. Mortalities of 0·1‐0·5% per day occurred for 3–4 weeks in fish stocked in circular ponds in the months of February and March when temperatures were falling from 23–11·C. The bacterium belonging to the Family Enterobacteriaceae had similarities withYersinia ruckeri(the RM bacterium) andSerratia liquefaciens. As a temporary designation SBS was used. It is recommended that its taxonomic position remain subjudicefor the present. Inoculation experiments on brook trout and landlocked Atlantic salmon indicated that signs appeared 2–7 days after inoculation and that rainbow troutSalmo gairdneriRichardson were resistant to t

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1980.tb00181.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Abstract.Giemsa stained blood smears prepared from blennies caught on the shores of southern England and from cod taken from the Celtic and North seas revealed fish with clinical ‘piscine erythrocytic necrosis’ (PEN). The findings recorded here extend the distribution data on PEN infections and report that the infection in the blenny and cod may possibly have a similar developmental pattern. Data are presented on the prevalence of the infection in the fish population samples and on the proportion of infected cells in the smears exami

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1980.tb00182.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Abstract.This paper reports for the first time the application of the direct negative staining technique for the rapid confirmation of the viral nature of blenny‘piscine erythrocytic necrosis (PEN). The virus in negatively stained preparations has an internal core structure which appears in exact opposite contrast to that seen in thin sectioned virus. The resultant images from both negative staining and thin sectioning suggest that the organization of the core is unique amongst intracytoplasmic deoxyriboviruses (ICDVs

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1980.tb00183.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Abstract.Electron microscopical and histopathological investigations were carried out on the anterior kidney often 1‐year‐old farmed rainbow trout naturally infected with the external signs of viral haemorrhagic septicaemia (VHS). The histopathology of the liver and the haematology of peripheral blood were also examined. The presumptive virus of VHS was directly demonstrated for the first time in the anterior kidney.All diseased fishes showed necrotic changes in the kidney and the liver. The melano‐macrophage centres of the anterior kidney showed a partial destruction accompanied with a loss of melanin. A progressive destruction of the erythrocytes was observed. The liver exhibited moderate to extensive necrosis (karyorrhexis and karyolysis with lymphocytic invasion in the necrotic areas). Neither intranuclear nor intracytoplasmatic inclusions were observed. In the peripheral blood diverse stages of erythrocytic degeneration, amitoses of the erythrocytes and a five‐fold increase in lymphocyte numbers were o

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1980.tb00184.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1980.tb00185.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1980.tb00186.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1980.tb00187.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY