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20种中草药杀灭离体小瓜虫的药效研究 总被引:7,自引:0,他引:7
选用20种不同中草药,研究其不同浓度的水提物对多子小瓜虫(Ichthyophthirius multifiliis)成虫、包囊和幼虫的离体杀灭实验效果。结果显示:0.1 g/L槟榔和乌梅对各个阶段的虫体均有杀灭效果,0.1 g/L大黄和黄芩1 h内对幼虫有杀灭效果,1.0 g/L浓度能杀灭成虫和包囊,表明槟榔、乌梅、大黄、黄芩的杀虫效果相对较好;贯众、乌药、枳壳等13种中药浓度达到10 g/L、50 g/L或100 g/L才具有一定杀虫作用,但效果不很显著;熟地黄、茯苓和黄芪即使浓度达到100 g/L时,也不能杀灭虫体。 相似文献
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小瓜虫病和车轮虫病均为重要的鱼类纤毛虫病。近年来对传统化学药物耐药的纤毛虫越来越多。本文介绍了用中药治疗团头鲂小瓜虫和车轮虫混合感染的过程,以期对类似病例治疗提供参考。 相似文献
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BACKGROUND: Infections of the ciliate protozoan Ichthyophthirius multifiliis Fouquet, 1876, can cause heavy mortalities in freshwater aquaculture systems. Following the ban of malachite green on fish for human consumption, currently available chemical therapies are only partially efficacious even when repeatedly applied. There is, therefore, an urgent necessity to identify more efficient and environmentally friendly control strategies. In the present study, the use of a substrate algae feeder leopard pleco, Glyptoperichthys gibbiceps, as a biological agent to control I. multifiliis infections on blue tilapia, Oreochromis aureus, reared in a warm‐water, experimental tank‐based system is explored. RESULTS: The free‐swimming protomont stage of I. multifiliis demonstrated selective settlement behaviour towards biofilm‐covered substrates. Following a controlled exposure, the number of I. multifiliis trophonts establishing on naive blue tilapia, O. aureus, was 4.9 ± 0.4 when reared with G. gibbiceps, significantly lower than when reared in isolation (13.3 ± 0.9; ANOVA, P < 0.001). CONCLUSION: This study demonstrates for the first time the potential of G. gibbiceps as a biological control to reduce I. multifiliis on commercially valuable fish stocks in warm‐water systems. This likely originated from the grazing activity of G. gibbiceps on the biofilm layer upon which the multiplicative stage of I. multifiliis was shown preferentially to settle. Therapeutic strategies against pathogenic protozoan species like I. multifiliis could greatly benefit from incorporating, where appropriate, a biological control targeting the external multiplicative life stages of the parasite, potentially reducing the current dependence on chemical interventions. Copyright © 2012 Society of Chemical Industry 相似文献
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Abstract Channel catfish, Ictalurus punctatus (Rafinesque), were immunized with Ichthyophthirius multifiliis (Ich) theronts and trophonts, and the immune response and host protection against both homologous and heterologous serotypes of Ich were evaluated. Immunizations were done with two immobilization serotypes (ARS4 and ARS6) of live theronts by bath immersion (trial I) and with sonicated trophonts by intraperitoneal (i.p.) injection (trial II). Cutaneous and serum antibody titres against Ich following immunization were measured and survival of catfish was determined after theront challenge. Theronts were immobilized by the antiserum from fish immunized with homologous theronts or trophonts, but not by the serum of fish immunized with the heterologous serotype. Serum from fish immunized by immersion with live theronts showed higher enzyme-linked immunosorbent assay titres against both homologous and heterologous serotypes than fish immunized by i.p. injection of trophonts. Channel catfish immunized by immersion with live theronts or by i.p. injection with sonicated trophonts developed an immune response against Ich and provided cross-protection against challenge from both serotypes (ARS4 and ARS6) of the parasite. Sonicated trophont antigens in aqueous solution by i.p. injection could stimulate an immune response in fish, but the immunity was of short duration. 相似文献
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This study explored the existence of apoptosis (programmed cell death) in Ichthyophthirius multifiliis Fouquet (Ich) theronts and determined the effect of cutaneous antibodies in skin culture fluid from fish immune to Ich on theront apoptosis. Apoptosis was detected in theronts and was clearly distinguished by fluorescent microscopy after staining with acridine orange and propidium iodide. The apoptotic theronts showed characteristic chromatin condensation and nuclear fragments containing chromatin pieces. The externalization of phosphatidylserine on the plasma membrane of apoptotic theronts was detected with fluorescein isothiocyanate-conjugated annexin using flow cytometry. Theront apoptosis was induced using the skin culture fluid from fish immune to Ich, which contained cutaneous antibodies against Ich. The highest apoptosis appeared in theronts exposed to immune skin culture fluid at a 1:10 dilution, compared with those at 1:20 and 1:40 dilutions. A direct correlation was noted between the percentage of apoptotic theronts and exposure duration to immune skin culture fluid. The study indicated that antibody reaction with theronts (immobilization) played an important role in theront apoptosis, but it could not be excluded that other components released from the excised skin had effects on theronts. 相似文献
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《Journal Of Applied Aquaculture》2013,25(1-2):155-161
ABSTRACT The objective of this study was to evaluate different salt concentrations in the treatment of Ichthyophthirius multifiliis. Silver catfish, Rhamdia quelen, fingerlings infected with I. multifiliis were submitted to four sodium chloride concentrations (g/L): 0,1,2, and 4 for 23 days. In a second experiment, fingerlings were maintained with 4 g/L salt, but for 45 days. Treatments with 2 and 4 g/L salt significantly increased fingerling survival compared with 0 and 1 g/L, and survival was significantly correlated with salt concentrations. In the second experiment, fish maintained at 4 g/L salt showed a gradual reduction of “white spots” and survival was 100%. Therefore, salt offers an alternative for treatment of silver catfish fingerlings infected with I. multifiliis. 相似文献
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De-Hai Xu Victor S Panangala Vicky L van Santen Kevin Dybvig Jason W Abernathy Phillip H Klesius Zhanjiang Liu & Riccardo Russo 《Aquaculture Research》2009,40(16):1884-1892
Ichthyophthirius multifiliis (Ich), a ciliated protozoan parasite of fish, expresses surface antigens (i-antigens), which react with host antibodies that render them immobile. The nucleotide sequence of an i-antigen gene of I. multifiliis strain ARS-6 was deduced. The predicted protein of 47 493 Da is comprised of 460 amino acids (aa's) arranged into five imperfect repeats with periodic cysteine residues with the structure: CX(19)20 CX2 CX16−27 CX2 CX20(21) CX3 . The N-terminal aa's typify a signal peptide motif while a stretch of C-terminal aa's resemble a glycosyl–phosphatidyl–inositol (GPI)-anchor addition site. The degree of deduced i-antigen aa sequence identity of strain ARS-6 (GenBank accession # ACH87654 and # ACH95659) with other I. multifiliis i-antigen sequences present in GenBank ranges from 99% to 36% identity with 52 kDa i-antigens of I. multifiliis strain G5 (accession #s AAK94941 and AAK01661 respectively). Immunoblot analysis of i-antigens following exposure of I. multifiliis theronts to catfish anti- I. multifiliis immune serum did not show any appreciable alteration in i-antigen expression. The mechanism that regulates i-antigen expression in I. multifiliis remains a puzzling question. 相似文献