Disease resistance and immune-relevant gene expression in golden mandarin fish, Siniperca scherzeri Steindachner, infected with infectious spleen and kidney necrosis virus-like agent.

Infectious spleen and kidney necrosis virus (ISKNV), family Iridoviridae, genus Megalocytivirus, may cause high mortality rates such as those seen in mandarin fish, Siniperca chuatsi. ISKNV has attracted much attention due to the possible environmental threat and economic losses it poses on both cultured and wild populations. We have investigated the pathogenicity of ISKNV-like agent Megalocytivirus, isolated from infected pearl gourami, in golden mandarin fish, Siniperca scherzeri - a member of the Percichthyidae family - and in another Percichthyidae species, S. chuatsi. Fish were challenged with four different doses of ISKNV-like agent Megalocytivirus (1, 10, 100 or 1000 µg per fish) over a 30-day period, and cumulative fish mortalities were calculated for each group. No significant mortality was observed for fish challenged with the lowest dose (1 µg per fish) relative to a control group. However, all other challenged groups showed 100% mortality over a 30-day period in proportion to the challenge dose. Quantitative real-time PCR was performed to measure mRNA expression levels for six immune-related genes in golden mandarin fish following ISKNV-like agent challenge. mRNA expression levels for IRF1, Mx, viperin and interleukin 8 significantly increased, while mRNA levels for IRF2 and IRF7 remained constant or declined during the challenge period.

Marine biofilms as mediators of colonization by marine macroorganisms: implications for antifouling and aquaculture.

In the marine environment, biofilms on submerged surfaces can promote or discourage the settlement of invertebrate larvae and macroalgal spores. The settlement-mediating effects of biofilms are believed to involve a variety of biofilm attributes including surface chemistry, micro-topography, and a wide range of microbial products from small-molecule metabolites to high-molecular weight extracellular polymers. The settled organisms in turn can modify microbial species composition of biofilms and thus change the biofilm properties and dynamics. A better understanding of biofilm dynamics and chemical signals released and/or stored by biofilms will facilitate the development of antifouling and mariculture technologies. This review provides a brief account of 1) existing knowledge of marine biofilms that are relevant to settlement mediation, 2) biotechnological application of biofilms with respect to developing non-toxic antifouling technologies and improving the operation of aquaculture facilities, and 3) challenges and future directions for advancing our understanding of settlement-mediating functions of biofilms and for applying this knowledge to real-life situations.

[Optimization of an enzyme immunoassay for the detection of antibodies against avian reoviruses--with special consideration of the calculation of results and test interpretation]. / Optimierung eines Enzymimmunoassay zum Nachweis von Antikörpern gegen aviäre Reoviren--unter besonderer Berücksichtigung der Ergebnisberechnung und Testinterpretation.

Selected steps in the establishment of an enzyme-immuno-assay (EIA) are shown with an EIA for detection of antibodies against avian reoviruses of chicken. The centre of this work is to show the various possibilities of calculation and interpretation of the test results. The definition of the cut-off-value is the basis for the interpretation of the assay and the consequences for the veterinarians in the field and the animal owners. Basic parameters (sensitivity, specificity, predication value, prevalence) of the test validation are discussed with the example of the examination of a new hen flock in the EIA, compared to serum neutralisation test.

[Comparative studies of the standardization of erysipeloid immune sera "Dessau" from swine using the mouse-protection test and ELISA]. / Vergleichende Untersuchungen zur Wertbemessung von Rotlauf-Immunseren "Dessau" vom Schwein mittels Mäuseschutz-Test und ELISA.

Different serological methods were used in determining the valence of red murrain immune sera. By using a grow test it is possible to accomplish an immunological differentiation of the immune sera. The used ELISA was tested in comparison to the conventional mouse protective test (PRIGGE, 1950) with regard to its valuation of immune sera. Both procedures have been tested on a possible correlation. In almost all cases a correlation between high titres in ELISA and a mouse protective value over 100 I.E. could be proven. The statistical processing of the test results proved an assumed correlation of both procedures. But it is necessary to carry out further research in order to be able to recommend this procedure as an alternative for the mouse protection test.

[Detection of antibodies against Brucella in the aqueous humor using ELISA]. / Nachweis von Antikörpern gegen Brucellen im Augenkammerwasser mittels ELISA.

In aqueous bulbi of experimentally against Brucella abortus immunized guinea pigs and rabbits specific antibodies could be detected by ELISA-tests. This first demonstration of brucella antibodies in the aqueous shows that aqueous can be used for serological examinations. For practical use more investigations in experimental animals are necessary, e.g. on kinetics of orbital antibodies absence of interfering factors and biomechanics of proteins in aqueous.

[Detection of Erysipelothrix rhusiopathiae specific antibodies in the serum of experimentally-infected swine by ELISA and immunoblotting]. / Nachweis von Erysipelothrix-rhusiopathiae-spezifischen Antikörpern in Seren experimentell infizierter Schweine mit ELISA und Immunoblotting.

In an attempt to characterize the immuno response of the animal organism to experimental infection, ELISA and immunoblotting were used to test the antibody levels of erysipelas hyperimmune sera (HIS) which had been induced by Erysipelothrix rhusiopathiae. Also, 5 pigs were accidentally chosen to check on individual curves of antibody formation, following periodical inoculation up to HIS collection. All HIS verified and confirmed by the mouse protective test responded by high titres. Yet, the results so far obtained from HIS titration have failed to be conclusive as to valency. The animals selected for these experiments exhibited differentiated antibody levels during the phase of immunisation, although they were at one and the same level, when measured by the final titre, following last boostering. The desired rise in antibody levels was achieved only by the 4th to 9th boostering in almost all cases. Extinction values determined by ELISA were confirmed or supplemented by the results obtained from immunoblotting.