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1.
Seventy-two epaulette sharks, Hemiscyllium ocellatum (Bonnaterre), were infected with the nematode parasite Proleptus australis Bayliss, 1933. The parasite population was overdispersed. Infection intensity ranged from 3 to 1002 worms per fish stomach, and there was a positive correlation between shark length and number of parasites present. The majority of worms were attached to the stomach wall, and scanning electron microscopy and histological examination showed that worms penetrated the stomach lining. Worms were observed within the lamina propria of the stomach and occasionally penetrated the muscularis mucosa. Little to no inflammatory or cellular immune reaction to the presence of the parasites was observed, except in one case where a worm was being degraded by a host tissue response. There was a large amount of connective tissue proliferation as a result of nematode attachment, but no obvious effects on the overall health of the sharks were seen. Three sharks were also found to be infected by the cestode Callitetrarhynchus sp.  相似文献   

2.
Abstract. The humoral immune response of turbot, Scophthalmus maximus (L.), to antigens from the microsporean parasite Tetramicra brevifilum Matthews & Matthews, 1980, was studied. Thirty days after intraperitoneal immunization with whole T. brevifilum spores in Freund's complete adjuvant, double indirect ELISA indicated that initial production of antibodies to parasite surface antigens was considerably higher than production of antibodies to the antigens contained in a crude extract (CE) of spores. Following re-immunization without adjuvant on day 30, levels of antibodies to surface antigens gradually declined, whilst levels of antibodies to CE antigens increased. The antibody response of intraperitoneally immunized fish was characterized by Western blotting of total soluble antigens obtained by heating and reduction of T. brevifilum spores at 95–100°C in Tris-HCl buffer containing SDS and dithiothreitol: a series of bands with molecular weights between 20 and 53 kDa was recognized by immunized turbot sera. Four additional bands (with molecular weights between 15 and 18kdA) were recognized by serum from re-immunized fish. ELISA studies of sera from naturally infected fish revealed a surprisingly low incidence of strong T. brevifilum seropositivity (61% individuals); antibodies to surface antigens predominated in seropositive individuals. The low background response levels and high sensitivity of the ELISA used in this study indicate that the assay is of value for the monitoring of serum antibody levels in turbot. However, given the relatively low seropositivities observed in naturally infected turbot, particularly to CE antigens, the use of anti- T. brevifilum serum antibody levels for the diagnosis of infection by this parasite may lead to false negative results.  相似文献   

3.
为研究三联特异性卵黄抗体对哈维氏弧菌、溶藻弧菌与副溶血弧菌的体外抑菌效果,通过制备哈维氏弧菌、溶藻弧菌与副溶血弧菌三联灭活疫苗,免疫蛋鸡。收集鸡蛋制备卵黄抗体并检测其效价、纯度和特异性。通过免疫荧光、扫描电镜和体外抑菌实验初步探究其制备的三联特异性卵黄抗体对三种弧菌的体外抑菌效果。结果显示,ELISA检测特异性卵黄抗体效价高达1:51200,并维持5周;SDS-PAGE对分离纯化的卵黄抗体分析显示,随着纯化步骤的进行,卵黄抗体中的蛋白杂带逐渐减少,纯度变高。免疫荧光和免疫印迹实验表明,特异性卵黄抗体与抗原的结合具有较高的特异性。扫描电镜进一步观察发现,相比非特异性卵黄抗体,特异性卵黄抗体处理过的弧菌,菌体互相黏附在一起,菌体细胞表面粗糙,细胞壁破损。在体外抑菌实验中,特异性卵黄抗体对弧菌具有明显的抑制效果,且抑制作用呈现剂量依赖性。综上所述,本研究制备的三联特异性卵黄抗体能够与哈维氏弧菌、溶藻弧菌和副溶血弧菌发生特异性结合,通过体外实验发现,卵黄抗体通过凝集和黏附,破坏菌体细胞的完整性,从而发挥抑菌作用。  相似文献   

4.
Abstract. Forty-five channel catfish, Ictalurus pitnctaius (Rafinesque), fingerlings were inoculated with Edwardsiella ictaluri to determine the usefulness of monoclonal antibodies for indirect fluorescent antibody techniques for confirming clinical diagnosis of enteric septicaemia of catfish. Bacteriological and indirect fluorescent antibody results were compared statistically and found to correlate in 90·3% of the cases. A method for incorporating monoclonals for indirect fluorescent antibody into the speciation of Edwardsiella ictaluri and the use of monoclonal antibodies in diagnosis is described.  相似文献   

5.
The influence of water temperature and water oxygenation on the specific antibody response was evaluated by indirect ELISA in sea bass (Dicentrarchus labrax L.) immunized against human‐γ‐ globulins emulsified in Freund's complete adjuvant. A higher antibody response was observed in fish reared at 24 and 30 °C, than at 12 and 18 °C. For the fish group reared at 24 °C, the immunological observation was carried out until 300 days after immunization. At the end of this period, fish kept at 24 °C still showed immunological competence, although the antibody response began to decrease significantly from 120 days after the immunization. Fish reared under mild hyperoxia and normoxia conditions had higher antibody responses than fish reared under mild hypoxia conditions. Moreover, at the end of the experimental period of 56 days the antibody response of fish reared under hyperoxia conditions was significantly higher than the immune response detected in fish reared under normoxia and hypoxia conditions.  相似文献   

6.
Abstract. Monoclonal antibodies specific to Bonamia ostreae (Ascetospora), the intrahaemocytic parasite of the flat oyster, Ostrea edulis L., were used in an indirect fluorescent antibody assay, firstly to define the subcellular location of their epitopes and, secondly, as a means of diagnosis of the disease.  相似文献   

7.
Infectious salmon anaemia is an important disease of Atlantic salmon. One of the current methods of diagnosis is the indirect fluorescent antibody test (IFAT), using a monoclonal antibody specific to the haemagglutinin of the virus. The conformationally dependent nature of this antibody could be a drawback in its usefulness in other tests. This study describes the development and optimization of a polyclonal antiserum against infectious salmon anaemia virus, including a method of separating virus from cell culture components within culture supernatant. The antiserum was subsequently optimized for use in a variety of immunological diagnostic tests, including IFAT and an alkaline phosphatase-based immunoassay, and Western blot.  相似文献   

8.
The histopathology, immunohistochemistry and ultrastructure of the alimentary canal of chub, Leuciscus cephalus (L.), from the River Brenta, naturally infected with the acanthocephalan Pomphorhynchus laevis Müller, 1776, was studied and described. Of 62 chub examined, 54 (87%) were infected with P. laevis ; the intensity of infection ranged from five to 130 parasites per host, and a density of 8 P. laevis per cm2 was common. Examination of histological material of infected chub revealed that both male and female acanthocephalans deeply penetrated all layers of the gut wall by means of their slender neck, bulb and proboscis. As a result, a capsule was formed around the bulb and proboscis on the external surface of the host intestine. In parasitized chub, four main types of reaction against the body of the acanthocephalan were recognized. Pomphorhynchus laevis caused local damage to the intestinal wall, eliciting catarrhal-erosive enteritis in the lumen and a fibroblastic-collagenous and fibro-epithelioid encapsulation in its thickness with tissue zonation according to the depth of parasite penetration. Furthermore, eosinophilic granular cells (EGC) within the inflammatory tissue were identified by immunohistochemical methods and transmission electron microscopy.  相似文献   

9.
The ability of rainbow trout, Oncorhynchus mykiss (RBT), to produce a localized mucosal immune response was investigated following intraperitoneal (i.p.) or peranal (p.a.) immunization with a protein-hapten carrier, fluorescein isothiocyanate conjugated to keyhole limpet haemocyanin (FITC/KLH). Antibody levels in serum, mucus, tissue culture supernatant from blood and spleen leucocytes, and excised skin, intestine and gill tissues were determined by ELISA. Significantly, elevated antigen-specific antibodies were elicited in both serum and mucus of fish immunized i.p. Mucosal antibody responses, in general, paralleled serum responses over time. Leucocytes isolated from spleen and blood of i.p. immunized fish at week 10 produced significantly elevated antibody levels against FITC when cultured in vitro. Excised skin, intestine and gill tissues from these fish also exhibited significantly elevated antibody responses indicating localized production in the mucosa from tissue-specific B cells. A localized mucosal immune response was elicited only after i.p. and not p.a. immunization, suggesting that systemically stimulated B cells migrate to mucosal tissues where they produce antibodies locally.  相似文献   

10.
Histochemical and ultrastructural investigations were conducted on the mucous cells of the intestine of brown trout, Salmo trutta L., naturally infected with the cestode Cyathocephalus truncatus (Pallas, 1781) and the acanthocephalan Echinorhynchus truttae Shrank, 1788. A subpopulation of 45 S. trutta were examined of which 15 specimens harboured E. truttae, 15 of which were infected with C. truncatus and 15 fish, the control group, were uninfected. In histological sections, hyperplasia and hypertrophy of the mucous cells were evident at the site of parasite infection. Enhanced mucus secretion was also recorded in infected fish. The number of mucous cells close to the site of parasite attachment within the intestine was significantly higher than the number detected in uninfected individuals and in infected individuals at sites 1 cm or greater from the point of parasite attachment. There were no significant differences between the number of mucous cells found at the latter two sites. Alcian blue and periodic acid‐Schiff’s staining of representative histological sections revealed a significant increase in the number of mucous cells staining positively for acid glycoconjugates compared to the number of cells found in the intestines of uninfected S. trutta. In transmission electron microscopy sections, each mucous cell typically possessed an elongated, basally positioned nucleus. The cytoplasm was observed to possess numerous electron dense and lucent vesicles, in addition to well‐developed rough endoplasmic reticulum, Golgi apparatus and a few round mitochondria.  相似文献   

11.
A systemic iridoviral disease associated with high mortality was initially recognized in cultured mullet, Mugil cephalus L., and tiger grouper, Epinephelus fuscoguttatus Forsskal, by histopathology and transmission electron microscopy. Polymerase chain reaction was performed on tissues and viral isolates, using four published primer sets developed for the Red Sea bream iridovirus (RSIV). An indirect fluorescent antibody test was also performed on virus-infected ATCC gruntfin (GF) and seabass, Lates calcarifer Bloch, (SB) cells using a monoclonal antibody, RSIV M10. Our results suggested that the mullet and tiger grouper iridovirus bears genetic and antigenic similarities to RSIV.  相似文献   

12.
Abstract. Rainbow trout that recovered from experimental Cryptobia salmositica infection 6 and 10 weeks earlier were protected against multiple intraperitoneal challenges of 50 000 and 10 000 parasites isolated from infected fish. The immunity was non-sterile; low parasitaemias were detected following a larger challenge (112 000 parasites). The indirect haemagglutination test was used to detect C. salmositica -specific agglutimns. Antibody titers increased during the first 18 weeks of infection. The infectivity of cultured C. salmositica was neutralized by incubation in heat-inactivated immune plasma. Infectivity of C, salmositica from infected fish was not neutralized by similar treatment. Complement fixing antibody was detected using the in vitro immune lysis test. Immune lysis occurred when cultured C. salmositica were used. Adoptive transfer of both leucocytes and plasma from immune fish conferred partial protection against the parasite in naive recipients. Complement fixing antibody may be important during early acute infection while phagocytosis may be important during the later chronic phase.  相似文献   

13.
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14.
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15.
Abstract. The African catfish, C. gariepinus (Burchell), a candidate species for aquaculture in southern Africa, is frequently infested by the branchiuran ectoparasite Dolops ranarum. Normal integument, as well as damage caused by this parasite, is described by means of scanning electron microscopy and histology. Wound healing and the attachment and feeding mechanism of the parasite is described.  相似文献   

16.
Enteromyxum leei is a myxozoan histozoic parasite that infects the intestine of several teleost fish species. In gilthead sea bream (Sparus aurata), it provokes a chronic disease, entailing anorexia, delayed growth, reduced marketability and mortality. Direct fish-to-fish transmission, relevant in aquaculture conditions, has been demonstrated for E. leei via effluent, cohabitation, and oral and anal routes. However, the minimum time of exposure for infection has not been established, nor the possible effect on the fish immune response. Two effluent trials were performed at different temperatures (high: average of 25.6°C; and low: constant at 18°C), different times of exposure to the effluent (1, 3, 5 and 7 weeks) and different population densities. The results showed that 1 week was enough to infect 100% of fish at high temperature and 58.3% at low temperature. High temperature not only increased the prevalence of infection in posterior intestine, but also induced a higher production of specific antibodies, limiting the progression of the infection along the intestine. Longer time of exposure to the parasite and higher fish densities facilitated E. leei infection. These results show that effective diagnosis, lowering animal density and removal of infected fish are key aspects to manage this disease in aquaculture facilities.  相似文献   

17.
Abstract. Two monoclonal antibody probes were produced against PK'X' cells. The parasites were partially purified by filtration and centrifugation of kidney tissue from rainbow trout with proliferative kidney disease and used as antigen for immunization of mice. The resulting monoclonal antibodies reacted with PK'X' cell antigens in enzyme-linked immunosorbent assay and immunohistochemistry tests. One antibody (Mab 12) appeared to be specific for PK'X'in kidney tissue, while the other (Mab 18) cross-reacted with host cell antigens in the kidney tubules. These probes are invaluable tools for the investigation of parasite surface antigens and life cycle studies.  相似文献   

18.
Abstract. Up to 88-9% of five-bearded rocklings, Ciliata mustela L., from three localities in Wales harboured the coelozoic myxozoan parasite Zschokkella russelli Tripathi. Previously recorded only from the gall-bladder of British rocklings, Z. russelli was also found to produce proliferation, enlargement and thickening of hepatic ducts, lowering of the duct epithelium and pericholangitis. Histological, scanning and transmission electron microscopy techniques were used to examine the parasite, and comparisons were drawn between Z. russelli from Welsh fish and infections recorded elsewhere, particularly from Plymouth, Devon.  相似文献   

19.
The results of comparative immunohisto-chemical staining studies with two lectin probes, GS-I and SBA, and five monoclonal antibodies raised against the PKX myxosporean are presented. In order to investigate the postulated link between PKX and Sphaerospora spp., the lectins and monoclonal antibodies were tested against PKX, Sphaerospora renicola, Sphaerospora oncorhynchi, Sphaerospora elegam, Sphaerospora truttae and Sphaero-spora sp. from Atlantic salmon, Salmo salar L., and Ceratomyxa shasta. SBA appears a useful tool for tbe diagnosis of all Sphaerospora spp. infections and was also positive for C. shasta. GS-I and monoclonal antibodies (12, C5, D4 and A3) appear to be specific for both the extrasporogonic and sporogonic stages of PKX. Although MabB4 was raised to PKX, it appears to stain some of the sporogonic stages of Sphaerospora spp. but not C. shasta. The results of the lectin and monoclonal staining of PKX and Sphaerospora oncorhynchi indicated that further work was required to prove or disprove the hypothesis that PKX and S, oncorhynchi are the same organism.  相似文献   

20.
A monoclonal antibody (designated MAb-007) was produced against the pathogenic haemoflagellate Cryptobia salmositica Katz. This IgG3 antibody recognized the 47-kDa antigenic polypeptide of C. salmositica (SDS-PAGE and Western immuno-blotting). The antibody did not agglutinate live parasites, and there was no change in the staining intensity of the 47-kDa band on Western immunoblots after immunoabsorption of MAb-007 with live intact parasites. The 47-kDa antigen recognized by MAb-007 was localized in the cytoplasm of the parasite (immunogold labelling and electron microscopy). The monoclonal antibody cross- reacted with the 47-kDa polypeptides of C. bullocki Srrout and C. catostomi Bower & Woo. It was used in an antigen-capture ELISA for the detection of parasite antigen in the plasma of rainbow trout inoculated with the parasite, or with an attenuated vaccine strain of C. salmositica. All pre-infection plasma were negative while all infected fish with detectable parasitaemias were positive for antigen at 1–9 weeks after infection. Parasite antigen was even detected in vaccinated fish that were negative for parasites using the wet mount microscopic technique. The antigen-capture ELISA detected C, salmositica antigen in whole cell lysate preparations at concentrations as low as 0.5 μg ml-1. Fifty microlitres of fish plasma was required in the antigen-capture ELISA, and the use of a plate reader and 96-well plates facilitated rapid analysis of a large number of plasma samples. The sensitivity of the assay makes it a potentially useful tool for detection of Cryptobia infections.  相似文献   

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