摘要:

Abstract.The histopathology of red‐sore disease, caused by the gram‐negative bacterium,Aeromonas hydrophila, is described for largemouth bass,Micropterus salmoides. Externally, lesions range from those affecting a few scales (pin‐point), to those associated with extensive chronic ulcerations; there is focal haemorrhage, oedema and dermal necrosis which exposes underlying muscles producing infiltration of mononuclear and granulocytic inflammatory cells. Internally, the liver and kidneys are foci for toxic products produced byA. hydrophilawith, in the most severe cases, complete destruction of the structural integrity of both organs. Pathological changes were not serious in either the spleen or heart, even in cases with massive damage in the liver and kidney. Internal and external lesions were similar in both natural and experimentally induced infections. The pathobiology of red‐sore disease in bass is postulated to be linked to elevated water temperature stimulating increased metabolism, decreased body condition and stress, leading to the increased production of corticosteroids and the concomitant rise in susceptibility to in

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1979.tb00169.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.Rainbow trout exposed to environmental free C02concentrations ranging from 12–60 mg/1 for a minimum of 275 days developed nephrocalcinosis. Gross, histopathological and chemical examinations demonstrated that prevalence and severity of nephrocalcinosis increased with increasing CO2concentrations. The condition was characterized by calcification and granuloma formation in kidney and stomach. Diet, but not water, PO4‐P concentration appeared to modify the prevalence and severity at each CO2concentration tes

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1979.tb00170.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.Fifty‐four per cent of the specimens in a sample of 147 lake whitefish (Coregonus clupeaformis) from northern Quebec exhibited a pronounced lack of bilateral symmetry in the distribution of metacercariae of the genusDiplostomum. This asymmetry was shown not to be a product of chance. A comparable degree of asymmetry was generated by a computer simulation incorporating a positive feedback mechanism. The simulation and the biological significance of such asymmetry are discusse

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1979.tb00171.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.The geographical distribution of an epizootic of perchPerca fluviatilisL., characterized by severe epidermal lesions and marked fish kills, is described. A wide variety of fungal and bacterial infections were found in diseased fish but the evidence suggests that they were not the primary cause of this condition. The primary pathogenic agent (assuming that it exists) or predisposing environmental factor has yet to be discovered. The severity of this disease is illustrated by monitoring the course of the epizootic in the perch population in Windermere. All age groups of fish were affected during the course of one year although the fish at spawning time appeared to be particularly vulnerable. There was a dramatic increase in the perch mortality in Windermere in 1976 and it is estimated that over 98% of the adult population (over 1 million fish) died in that year.

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1979.tb00172.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.Incidental observations of Atlantic tomcod during routine laboratory processing revealed that a portion of the adult population collected during the 1977–78 spawning season had enlarged livers containing dark coloured tumours and other abnormalities. Of the total of 264 livers collected between 16 January and 27 February 1978 and grossly examined for prevalence of abnormalities, 25% appeared to contain neoplastic nodules and hepatocellular carcinoma. One liver contained a massive tumour (7 × 12 mm) that involved approximately 60% of the liver. The exact causes of the high prevalence of hepatocellular carcinoma are unknown but poly‐chlorinated biphenyls (PCBs) are suspected of having a possible role. The Hudson River is known to contain elevated concentrations of PCBs. Twelve tomcod livers from the 1977–78 spawning population representing both normal and hepatoma conditions contained concentrations of PCBs ranging from 10–9 to 98–2 ppm (mean of

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1979.tb00173.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.The activity of piromidic acid (PA, 8‐ethyl‐5, 8‐dihydro‐5‐oxo‐2‐prior lidinopyrido [2,3–d] pyrimidine‐6‐carboxylic acid) against bacteria in fish was evaluatedin vitroandin vivo.In vitro, PA was effective against a wide range of pathogenic bacteria stocked in this laboratory and freshly isolated from fish. PA was active against organisms showing multiple drug‐resistance and showed no cross‐resistance to chloramphenicol, tetracycline and sulfamonomethoxine.In vivo, orally administered PA was effective against experimental infections withAeromonas hydrophilaandVibriospp. in goldfish and eels. The efficacy of PA against these infections was equal to or higher than that of chloramphenicol, and higher than that of tetracycline. Distribution of PA in the Ash was investigated by bioassay and autoradiography. In the bioassay, orally administered PA was easily absorbed and distributed in the blood and tissues of major organs within 1 h after the administration. Peak levels were attained 2 to 4 h post dosing, and no residue was detected in the blood and tissues 48 h post dosing. The results obtained from the autoradiographic investigation in goldfish were similar to those from the bioassay. Therapeutic levels of PA were well tolerated by fish when

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1979.tb00174.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.The spleen, kidney and liver melano‐macrophage centres of 14 species of clinically normal teleost fish were examined histochemically for ferric iron. Iron was present in varying amounts within the splenic centres of most specimens, but by contrast it was rarely found in the centres of the kidney and the liver.Under conditions of starvation and in diseased fish, a markedly increased deposition of ferric iron occurred in the splenic centres of nearly all fish examined. By comparison, the iron content in the kidney and liver centres was generally still very low. These results suggest that there exist important functional differences between the pigment centres of different haemopoietic tissues of teleost

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1979.tb00175.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1979.tb00176.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Book reviewed in this article:Primer of Serology. By A.N.C. Delaat.Diseases of Fishes. Enviro and Fish Diseases. Book 5. G. A. Wedemeyer, F. P. Meyerand I. Smith.Salmaon and Trout farming in Norway. By D. J. Edwards.Methods for Physical&Chemical Analysis of Fresh Waters, IBP Handbook No. 8. 2nd edn. By H. L. Golterman, R. S. Clyno&M. A. M. Ohnstad.

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1979.tb00177.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY