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1.
Antibody against Aeromonas salmonicida was detected in sera from immunised or experimentally infected rainbow trout by enzyme-linked immunosorbent assay (ELISA) using the biotin-avidin system. The ELISA titre correlated well with the agglutinin titres of the sera, but the ELISA was found to be more sensitive than the agglutination test. When the rainbow trout serum was separated by column chromatography, antibody activity (determined by ELISA and agglutination test) was detected in the IgM fractions. Minimum cross reaction was observed in the ELISA system between antigen prepared from A salmonicida and antibodies against Vibrio species and other species of Aeromonas. The specificity of the ELISA was also confirmed by inhibition test. Immunisation of rainbow trout with a virulent strain of A salmonicida provided good protection, though no correlation was observed between the protection and the ELISA titres of sera.  相似文献   

2.
A comparative pharmacokinetic study was conducted in rainbow trout (Salmo gairdneri) and African catfish (Clarias gariepinus) following intravenous (i.v.) and intramuscular (i.m.) administration of oxytetracycline (OTC) at a dose rate of 60 mg/kg body weight. Trout and catfish were kept in aerated tap water in tanks at constant temperatures of 12 degrees C and 25 degrees C, respectively. The two- and three-compartment open models adequately described plasma drug disposition in African catfish and rainbow trout respectively, following i.v. OTC administration. Compared to catfish (COP = 86 +/- 10 micrograms/ml) an eightfold higher extrapolated zero time concentration was obtained in trout (COP = 753 +/- 290 micrograms/ml). A significant difference was observed with respect to the relatively large apparent distribution volumes (Vd(area] after i.v. OTC administration (trout, mean value: 2.1 l/kg; catfish, mean value: 1.3 l/kg). The mean final elimination half-lives of both fish species were greater than previously reported in mammals (trout, 89.5 h; catfish, 80.3 h). A mean maximum plasma concentration (Cmax = 56.9 micrograms/ml) was obtained in trout at 4 h after i.m. administration of OTC. In catfish a lower Cmax of 43.4 micrograms/ml was determined at about 7 h. No significant difference was observed with respect to bioavailability following i.m. administration of OTC (trout, 85%; catfish, 86%).  相似文献   

3.
Abstract

A primary intraperitoneal (IP) vaccination of extracellular products (ECP) from Mycobacterium spp. (strains TB40, TB267, or Mycobacterium marinum) mixed with Freund's incomplete adjuvant and followed by a secondary IP injection at 8 weeks resulted in the elevation of both the nonspecific and the specific immune responses of rainbow trout Oncorhynchus mykiss. Increased nitroblue tetrazolium and phagocytosis activity were observed in these fish; peaks in activity occurred at weeks 2 and 6 after primary immunization with a third peak at week 10. Lysozyme activity, on the other hand, peaked at weeks 2 and 8 after primary immunization except in the TB40-immunized group. A third peak of lysozyme activity was observed at week 10 after primary immunization. The activity of the specific immune response was monitored by an enzyme-linked immunosorbent assay and Western blot. The results indicate that antibodies to the ECP of Mycobacterium spp. were present in rainbow trout serum and that they reacted with major ECP antigens at 65 and 16 kDa (kilodaltons) as well as with some minor antigens at 48, 46, and 40 kDa.  相似文献   

4.
The phagocytosis of Vibrio anguillarum by peritoneal macrophages from normal rainbow trout was enhanced by antibody and complement. Treatment of either macrophages or the bacteria by antibody also enhanced opsonisation. Five weeks after immunisation with V anguillarum, the phagocytic activity of macrophages from rainbow trout was increased significantly compared with the activity of those from unvaccinated fish. Although agglutinin titres did not increase until three weeks after immunisation, seven out of 10 fish challenged one week after immunisation survived, indicating that immunised fish had developed resistance to vibrio infection before significant levels of antibody or phagocytic activity became detectable.  相似文献   

5.
A fragment (called frg#11, amino acids, aa 56-110) of the protein G (pG) of viral haemorrhagic septicaemia virus (VHSV) was designed after previous results showed it to be recognised by approximately 40% of the trout immunised to VHSV [Dis. Aquat. Organ. 34 (1999) 167]. frg#11 was then cloned, expressed, purified and used to study the production of antibodies to its epitopes in trout immunised to VHSV. Anti-frg#11 trout antibodies could be detected in serum from individual trout surviving VHSV exposure, immunised by injection with purified VHSV or DNA-immunised with its pG gene whereas it was not detected in non-infected and non-immunised trout. The trout serum antibodies which reacted more strongly by ELISA using solid-phase frg#11 (continuous or linear epitopes on the sequence of the pG) had the lowest VHSV-neutralising activity (epitopes which are pG conformation-dependent). Because antibodies recognising continuous as well as conformation-dependent epitopes of the pG seem to be involved in protective trout immunological responses to VHSV, the estimation of anti-frg#11 antibodies could help to the dissection of the complex trout antibody response to VHSV infections. In addition, these preliminary results suggest that the determination of anti-frg#11 antibodies might also be used to complement in vitro viral neutralising assays which seem to be restricted to pG conformation-dependent epitopes.  相似文献   

6.
A procedure established for the selective isolation of the species of Streptococcus responsible for rainbow trout streptococcosis in South Africa, consisted of the inoculation of samples into nutrient broth which had been supplemented with 100 micrograms/ml of nalidixic acid, 160 micrograms/ml of oxolinic acid or 200 micrograms/ml of sodium azide. After incubation, the sample was plated onto tetrazolium agar on which the rainbow trout pathogenic Streptococcus species grew as a red colony. The colonies were isolated from the tetrazolium agar and identified as rainbow trout pathogenic isolates by biochemical and serological tests. In the laboratory the selective procedure is capable of detecting about 2 bacteria per ml. This procedure was used in the field and biochemically identical Streptococcus species were found in the mud and a freshwater crab from the water source of a site with a history of streptococcosis.  相似文献   

7.
Jones, S. G., Kamunde, C., Lemke, K., Stevens, E. D. The dose–response relation for the antinociceptive effect of morphine in a fish, rainbow trout. J. vet. Pharmacol. Therap.  35 , 563–570. There have been suggestions that analgesics be used by fish researchers. But in the absence of dose–response data for morphine, this suggestion seems imprudent. The purpose of the present study was to develop a dose–response relationship in fish using six doses of morphine. The response (movement of the fins or tail) to a noxious stimulus (electrical shock to the face region) was monitored before and after a dose of morphine intraperitoneally (i.p.). The i.p. dose of morphine ED50 in rainbow trout was 6.7 ± 0.8 mg/kg (n = 12 at each dose). The plasma morphine concentration EC50 was 4.1 ± 1.5 mg/L. In a second experiment, rainbow trout tested with equal amounts of morphine and naloxone (30 mg/kg) showed that the antinociceptive effect of morphine was blocked by naloxone. It has been suggested that stress‐induced analgesia has been a confounding factor in some fish studies. However, plasma cortisol levels in our study indicated that stress was not a confounding factor in the present experiments. The ED50 for morphine in fish was higher than that reported for humans or other mammals. Our observation showing a dose–response relation for morphine using a noxious stimulus supports arguments for its effectiveness as an antinociceptive drug in fish.  相似文献   

8.
Young cultures of rainbow trout macrophages were found to significantly increase in diameter following addition of muramyl dipeptide or of supernatants from testis/FCA sensitised leucocytes incubated with spermatozoa, or a testis extract. However, such supernatants caused little migration inhibition or increase in phagocytosis of spermatozoa by macrophages, whereas opsonization of spermatozoa with anti-sperm serum caused an almost six-fold increase in phagocytosis. These results suggest an interplay between humoral and cell-mediated immune reactions upon macrophages during experimental autoimmunity to the testis in trout.  相似文献   

9.
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10.
Chlorinated dioxins, as typified by the most potent isomer, TCDD, are immunosuppressive in mammalian species and can enhance the susceptibility to a number of diseases. In recent years chlorinated dioxins have been detected in fish in many freshwater and marine habitats. Thus far, the effects of these chemicals on the immune responses of fish have not been examined. We studied the influence of TCDD on the defense mechanisms of rainbow trout. Yearling trout were injected intraperitoneally with the vehicle, 0.1, 1.0 or 10 micrograms/kg of TCDD. Interactions with the humoral immune response to sheep red blood cells (SRBC) were assessed by the Jerne plaque assay using head kidney and spleen leukocytes. Serum antibody was measured by complement-mediated lysis of SRBC in a chromium release assay. Effects of TCDD on the cellular immune responses were evaluated by the response of thymic and splenic lymphocytes to Con A and PWM. In addition, the phagocytic activity of peritoneal macrophages was examined in vitro. Trout which received 0.1 or 1.0 micrograms/kg TCDD remained clinically normal, and defense mechanisms were unaltered in these fish. Trout which received 10 micrograms/kg of TCDD became hypophagic and exhibited fin necrosis, ascites and suppression of hematopoiesis. In this treatment group, Con A-induced blastogenesis of thymic and splenic lymphocytes was not significantly changed, however, suppression of the PWM-induced response of splenic lymphocytes occurred. No statistically significant alterations occurred in humoral immune responses, and phagocytic activity of peritoneal macrophages was not decreased. The dose-response curve for various biologic effects of TCDD in the rainbow trout appears different from that in sensitive mouse strains. The 30-day, single-dose, parenteral LD50 for TCDD in the C57BL mouse is 100 micrograms/kg, and TCDD suppresses both cell-mediated and humoral immune responses at 1-2 micrograms/kg in this mouse strain. In the rainbow trout, however, immunosuppression was evident only at doses of TCDD approaching the 80-day, single-dose, parenteral LD50 of 20 micrograms/kg.  相似文献   

11.
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12.
Antigens in the extracellular protein (ECP) complexes of Bacteroides nodosus, isolated from sheep with either benign or virulent footrot, were studied by immunoelectrophoresis (IEP). Rabbit antisera against ECP from virulent and benign strains, were used in homologous and heterologous crossed IEP. Four precipitin peaks unique to the virulent strain, and five peaks unique to the benign strain were identified. In an attempt to characterize the different antigens in ECP, rabbit antisera were raised against an outer membrane protein (OMP, mol. wt. 35 000 daltons), pili and various proteases of virulent and benign strains of B. nodosus. No precipitin band was observed when ECP from both B. nodosus strains were reacted against anti-OMP and anti-pilus antisera. However, single precipitin bands unique to one protease from the benign strain and one protease from the virulent strain were identified. The results suggest that specific antigens other than proteases or pili are important in determining whether a B. nodosus isolate is virulent or benign.  相似文献   

13.
Cattle infested with the common cattle grub, Hypoderma lineatum (Villers) develop specific humoral antibodies and a cellular immune reaction, defined by delayed-type hypersensitivity, to purified H. lineatum proteins. This investigation was designed to study the antigen-specific bovine lymphocyte response to hypodermin A (HyA), a serine protease of larval first-instar H. lineatum. Calves were vaccinated with either native or denatured HyA, and challenge-infested with H. lineatum. The kinetic development of a cellular immune response to HyA was monitored during vaccination and infestation. The HyA-specific responses were highly variable and weak during vaccination and infestation. Although HyA-specific lymphocyte blastogenic responses were observed, no correlation was noted between the magnitude of antigen-specific, peripheral lymphocyte proliferation and larval mortality. In striking contrast to responses observed during infestation, intense HyA-specific lymphocyte responses were observed with 3 calves 6 months after recovery from infestation. In addition, those responses were further heightened by a 250 micrograms booster injection of pure HyA.  相似文献   

14.
Poor quality eggs produced by the fully homozygous doubled haploids (DHs) may impair generation of clonal lines in fish species. In the present research, gynogenetic development of rainbow trout (Oncorhynchus mykiss) was induced in eggs originated from the DH females. Eggs were activated with the UV‐irradiated grayling (Thymallus thymallus) spermatozoa and subjected to the high hydrostatic pressure (HHP) shock to provide diploid clonal individuals. Only two of four DH females produced eggs that were successfully activated by the irradiated spermatozoa and subsequently developed into the gynogenetic embryos. Survival rates of rainbow trout from the clonal lines equalled 21.5% and 19.8% during embryogenesis and decreased after hatching to 18.6% and 14.9%, respectively. Some of the dead rainbow trout clones collected between hatching and swim‐up stage were emaciated and exhibited spinal deformities including scoliosis. Provided results confirmed limited developmental competences of eggs produced by rainbow trout DH females. Clonal rainbow trout developing in such eggs exhibited reduced survival and increased frequency of the body abnormalities.  相似文献   

15.
Successful active immunisation of horses against tetanus is dependent on a number of factors of which the toxoid preparation used, its method of application and the ability of the individual horse to respond are fundamental. Two immunisation schedules using an aluminium-based toxoid preparation were examined and the protection determined by monitoring the level of antitoxin afforded by each schedule. The results obtained demonstrated that 2 doses of this toxoid are necessary to ensure 12 months protection in all horses. These results are discussed in relation to the factors involved in active immunisation against tetanus.
Reference is also made to the occurrence of a transient phase of reduced levels of antitoxin following booster doses of toxoid in immunised horses during which it is considered these horses could become more susceptible to tetanus. The effect of a booster dose on immunised horses was examined and while there can be a reduction in the level of antitoxin in some immunised horses following this dose its effect is minimal, short-lived and for all practical purposes can be disregarded. The application of the booster dose in practice is also discussed.  相似文献   

16.
Abstract

Adult rainbow trout Oncorhynchus mykiss were immunized with formalin-inactivated, concentrated infectious pancreatic necrosis virus (IPNV). Although the immune response was variable among fish inoculated with a given virus type, sera were obtained that contained high titers of antibodies against known representatives of each of the three major serotypes and several unclassified field isolates of IPNV. Preparations of semipurified macroglobulins from the rainbow trout were subsequently used for comparative cross-neutralization testing of viruses. Cross-reactions were generally low between serotypes; however, diversity and heterogeneity existed among viral isolates from North American hatcheries (e.g., within serotype 1). For example, the Jasper subtype was clearly serologically distinguishable from other western Canadian isolates and from typical eastern Canadian isolates, which were similar to U.S. isolate VR 299. Specific salmonid immunoglobulin is suggested as a possible supplemental reagent, together with mammalian polyclonal and monoclonal antibody, for determining the epidemiology of IPNV in North America.  相似文献   

17.
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18.
The aims of the present study were to determine (a) the effectiveness of an attenuated live Cryptobia salmositica vaccine; (b) the effects of food deprivation on the immune response and its duration in rainbow trout (Oncorhynchus mykiss) immunised with a live C. salmositica vaccine or with a killed Aeromonas salmonicida vaccine. The fish were divided into three groups (I, II and III; 14 fish per group), those in Groups I and II were under food deprivation (0.40% of body weight), while Group III fish were fed to satiety. The study showed that the attenuated strain of C. salmositica did not cause anaemia and disease, and the fish were protected from clinical disease when they were challenged with virulent parasites. Parasitaemia in all fish vaccinated and challenged with virulent C. salmositica fluctuated and was relatively low; however, fish in Group III had higher parasitaemia than those in Groups I and II between weeks 8 and 14. The numbers of activated neutrophils increased [nitroblue tetrazolium (NBT) assay] after immunisation with both Cryptobia and Aeromonas vaccines and they remained high throughout the experiment. Antibody production (ELISA values) increased after vaccination and were slightly higher in Group III. ELISA titres against A. salmonicida increased after vaccination and decreased after 5 weeks. The titres increased again after the vaccinated fish were given booster, and they were higher than those in the first vaccinated fish.  相似文献   

19.
A combination of sulphadiazine and trimethoprim at a ratio of 5:1 (SDZ/TMP) was tested for possible immunomodulatory effects. The aim of the study was to follow the immune response after vaccination with simultaneous drug treatment. The fish were immunised with a commercial oil-based divalent (furunculosis/vibriosis) vaccine and were simultaneously given oral drug treatment. The specific immune response was monitored by analysing the levels of specific antibodies with ELISA. As indicators of the nonspecific immune response, the lysozyme activity of serum was measured and the phagocytic activity of circulating leucocytes was monitored by a chemiluminescence assay. Total circulating leucocyte counts and differentials were also monitored. The disease resistance was evaluated by challenge tests at the end of the experiment.The results indicate that SDZ/TMP at a ratio of 5:1 does not interfere negatively with the immune response in rainbow trout after vaccination. A slight stimulation in the antibody response as well as in the chemiluminescence response of circulating granulocytes was recorded in fish treated with the drugs in connection with vaccination. The drugs did not significantly affect the survival after challenge.  相似文献   

20.
Discovery of fish exhibiting clinical signs of ceratomyxosis in Washington State prompted concern over the potential impact of the myxozoan parasite Ceratomyxa shasta on native stocks of steelhead Oncorhynchus mykiss (anadromous rainbow trout). To investigate these concerns, a survey of 16 freshwater systems within the Puget Sound watershed, including Lake Washington, was conducted by sentinel exposure of susceptible fish (cutthroat trout O. clarkii and rainbow trout). Fish were exposed for 7 d during September 2003 and May 2004 and then were returned to a holding facility for monitoring of disease signs. Mortality caused by the parasite occurred only in the exposure group held at the University of Washington Hatchery, which receives its water from Portage Bay of Lake Washington. Fish from all other sites were negative for C. shasta, both visually and by polymerase chain reaction (PCR) assay, except for a single fish held at the Tumwater Falls Hatchery in September 2003. A single deformed spore was detected in that fish, but infection could not be confirmed by PCR and the parasite was not detected from any other fish held at that site during either the September or the May exposure. From these results, we conclude that C. shasta is not likely to have contributed significantly to the decline of steelhead populations throughout Puget Sound.  相似文献   

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