摘要:

AbstractThe biochemical properties and antibiotic sensitivity patterns of 13Pasteurella piscicidaisolates from Greece are described and compared with 10 Japanese and five European (Italian and French) isolates. Morphologically and biochemically, all isolates ofP. pisciddatested were nearly identical and only minor differences could be detected with reference to the level of acid production from sugars (especially from glucose). Greek, Italian and French isolates showed similar antibiotic sensitivity patterns, being resistant to erythromycin, kanamycin and streptomycin, and sensitive to most of the other antibiotics tested. Resistance was also demonstrated for some isolates towards the potentiated sulphonamides. The Japanese isolates appeared to be resistant to a larger range of antibiotics including erythromycin, kanamycin, streptomycin, oxolinic acid, oxytetracycline and chloramphenicol. Multiple resistance of Japanese strains was also noted. These results are discussed in the light of future measures for the control of pasteurellosis.

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1995.tb01260.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract.Rainbow trout developed a humoral immune response against numerous antigens of sonicated amoebae which were emulsified with Freund's complete adjuvant and injected into the peritoneum. The amoebae were cultured from the gills of Atlantic salmon, Salmo salar L., affected by amoebic gill disease. Antibodies in fish sera were detected by both enzyme‐linked immunosorbent assay (ELISA) and immunoblotting. Non‐spedfie reactivity in fish serum against Escherichia coli, the bacterium used in co‐cultivation of amoebae in vitro, was removed by immunoadsorption. Results obtained using ELISA and immunoblotting were comparable and indicated no significant difference in response to immunization with 10, 50 or 250 μg of sonieatcd amoebic protein. Amoebae contained immunogenie components of>100, 100, 89, 49, 37 and

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1995.tb01261.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractThe lesions of an enterococcal septicaemia occurring in turbot,Scophthalmus maximus(L.), cultured in several farms in northwest Spain are described. The agent of this septicaemia was identified previously as anEnterococcus‐like bacterium. Two main patterns of lesions were observed in the diseased turbot: a focal form characterized by exophthalmia, muscular haemorrhages, acute branchitis, and suppurative inflammation of periorbital tissues, eyeball, meninges and brain; and another generalized form with similar lesions, but showing more extensive haemorrhages, ulceration and purulent inflammation of the skin, desquamative enteritis, and necrosis of spleen and kidney. Fatty changes of the liver were observed in all turbot examined (diseased and controls), which indicates that these alterations were not related to the infection. Experimentally inoculated turbot developed lesions corresponding to the generalized form of the natural disease. Although theEnterococcusstrain was recovered in pure culture from all the organs, Gram‐positive bacteria could not be visualized histologically in the lesions of muscle and br

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1995.tb01262.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractBacteria capable of inhibiting growth of a pathogenicVibriosp. were isolated from the gastrointestinal tract of cultured halibut larvae during the first feeding and weaning stages. No such bacteria were found among isolates from the surface of eggs or the gastrointestinal tract of yolk sac larvae. The fraction of pathogen‐inhibitors among the total number of isolates ranged between 0–100% (first feeding) and 0–66% (weaning). All pathogen‐inhibitors were Gram‐negative rods, and 95% were oxidase and catalase positive fermentative isolates, capable of producing acid aerobically from a varying range of carbohydrates. These isolates possessed the characteristics of theVibrio/Aeromonas‐group, but only 19% were sensitive to the vibriostatic agent 0/129. Isolates from eggs and yolk sac larvae were dominated by bacteria belonging to theCytophaga/Flexibacter/Flavobacterium‐ group. The high fraction of isolates with the ability to inhibit growth of the pathogenicVibriosp. among the total number of isolates indicates that pathogen inhibition may be an important mutualistic role of the intestinal flora of early life stag

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1995.tb01263.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractSnakeheads,Channa striatus(Bloch), were inoculated with a spore suspension of the specific pathogenicAphanomyces, isolated from fish affected by epizootic ulcerative syndrome (EUS), in South East Asia. Fish were held at three different temperatures: 19, 26 and 31 °C. Histological changes induced by the infection are described. In the early stages of the disease, degenerative changes were observed in all samples, but inflammatory infiltrate was much more marked in fish kept at 26 and 31 °C. By 8 days post‐injection, extensive mycotic granulomatosis was observed in the samples kept at 26 and 31 °C. The fish kept at 19 °C developed a severe invasive myonecrosis with limited macrophage response. From 14 to 28 days post‐injection, healing became well established at 26 and 31 °C and surviving fish kept at these temperatures recovered completely by 28 days. The lesion was still progressing at 21 days post‐injection in fish kept at 19 °C, and all such fish succumbed by this time. Thus, mortalities in the fish kept at 19 °C were considerably higher than in the groups of fish kept at 26 and 31 °C. The findings help to explain why mortalities from EUS occur when water tempera

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1995.tb01264.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractA skin disease of intensively reared salmonids in Ontario hatcheries, known to the farmers as‘no‐mucus skin disease’, is reported for the first time. It was characterized by erosive and ulcerative lesions found mainly on the flanks of fingerlings, which resulted in exposure of the tips of the scales. Associated with these lesions were colonies of bacteria seen in the SEM to be clustered round the mucous cell pores and under‐running the margins of epithelial cells. The cause of this condition is unknown, although the response of fish to formalin treatment, and the presence of bacilli seen in skin scrapings and in the SEM, suggest that bacteria are resp

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1995.tb01265.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractCopepodids ofCaligus epidemicussurvived for up to 7, 8 and 5 days at 19, 22 and 26 °C, respectively, without food. Activity was high up to 3 days and then declined, but 3‐ or 4‐day‐old copepodids were more infective than younger copepodids, suggesting an initial dispersal phase. Although the success of attachment to perchlets,Ambassis marianus, was higher in small volumes of water, there was no statistically significant association between water volume (1, 4, 60 and 2001) and success of attachment. Most copepodids and early chalimus stages in single and multiple infections were attached to the pectoral fins, but did not settle preferentially beside other copepodids on the skin of the host. The parasite was overdispersed (negative binomial distribution) when groups of fish were exposed to 100 copepodids. Perchlets were killed when exposed to large numbers of copepodids and adultC. epidemicus, but survived for at least 5 days after exposure to 25 or fewer copepodids and five or fewer adults (although not necessarily all att

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1995.tb01266.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractAn epidemiological longitudinal study comprised information obtained from 124 randomly selected Norwegian sea‐sites housing post‐molts of Atlantic salmon,Salmo salarL. Information on crude cumulative mortality, fish characteristics and farm factors was gathered by the veterinary practitioners servicing the farms. The observation period lasted from the time of sea transfer of the smolts in the spring until 1 October 1991. On average, 116480 smolts were transferred to each sea‐site. The mean crude cumulative mortality of post‐smolts during the period concerned was 16.8%. The cumulative farm‐level incidence was 54.0% for furunculosis, 39.5% for infectious pancreatic necrosis (IPN) and 10.5% for vibriosis. Occurrence of any of these specific infectious diseases in the post‐smolt was significantly associated with mortality. The risk of furunculosis was significantly related to the location of the sea site. Mixing of smolt from many freshwater hatcheries in the sea farm increased the risk of IPN significantly. In addition, the risk of IPN was related to age of site and geographic location. The mean cumulative mortality in 1‐year‐old smolt groups was 17.5%, significantly greater than in two‐year‐old fish (7.9%). In addition, the method used to transport fish from the freshwater hatchery to the sea site was significantly associated with mortality. Neither the weight of smolts at sea transfer nor the date of transfer were significantly r

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1995.tb01267.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1995.tb01268.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0140-7775    

DOI:10.1111/j.1365-2761.1995.tb01269.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY