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1.
Between 1989 and 1997 different factors related to warble fly infestation (prevalence, intensity, climate, breed) were studied in north-eastern Algeria. Mean prevalence during the period was 76%. This figure was obtained from a cattle market survey of four different regions (Jijel, Constantine, Guelma, and El Tarf). One-hundred percent of the herds were found to be infested in El Tarf and 61% of animals were infested. Within a herd, the intensity of infestation decreased with the age of the cattle. The mean number of warbles per animal decreased as reinfestations occurred. The peak of the emergence of warbles observed between January and March was progressively delayed in the older animals. Two species of Hypoderma were present in cattle in Algeria (H. bovis and H. lineatum) with a predominance of H. lineatum (63%) in the semi-arid area (Batna) and a majority of H. bovis (75%) in humid area (Jijel). Warbles appeared earlier in Batna (October) than in Jijel (November). The Prim'Holstein breed was more susceptible to the warble fly infestation than Montbeliard or local breeds. The implementation of a control programme for hypodermosis in Algeria is urgent. Control can be achieved through a mass treatment of cattle. This approach must take into account the factors described in this study which influence the epidemiology of the disease. 相似文献
2.
Knowledge of the internal life cycle of goat warble fly infestation is scarce despite ample data available on the aetiology, epidemiology, immunodiagnosis and treatment of such infestations. This study was carried out at the slaughterhouse of Rossano Calabro (Cosenza, southern Italy) on 154 animals from 10 months to 6 years of age from May 1997 to June 1998. 1206 Przhevalskiana silenus larvae were collected during the trial period from the subcutaneous tissue of the slaughtered animals. The larval stage average size ranged from 4.7 mm, for first instar larvae (May), to 16.6 mm, for third instar larvae (February), in the first cycle of infestation. No larvae were found in March-April, coinciding with the pupation period. Small first instar larvae were found at the beginning of the second cycle of infestation (May-June). Necroscopic examinations were also carried out on internal organs and no larvae were found. The results pointed out that the internal life cycle of P. silenus is exclusively subcutaneous and there is no internal migration of the larvae. 相似文献
3.
The potential for cross-transmission of Hypoderma lineatum from cattle to domestic goats (Capra hircus) was examined using artificial infestation techniques. Two routes of infestation, subcutaneous injection and dermal penetration, were used to expose goats to newly hatched first instars. Presence of antibodies and appearance of circulating antigen (hypodermin C) were evaluated at selected intervals for up to 40 weeks post-infestation. In addition, immunoblots against H. lineatum first-instar proteins were conducted using sera taken at 10 weeks post-infestation. Goats were palpated for the presence of developing larvae at sub-dermal sites beginning at week 30 pi. No developing larvae were palpated at any time, regardless of the route of infestation nor was circulating antigen detected in any infested goats. Antibodies were present at weeks 6 and 10 and week 27 pi in both infested groups. Immunoblots indicated all infested goats produced antibodies to first instar H. lineatum antigens. H. lineatum appears to be incapable of completing development in domestic goats although the transient appearance of ELISA detectable antibodies and the presence of bands on immunoblots suggests that at least some larvae survive long-enough to engender a humoural response. The host specificity of H. lineatum is discussed in light of the general concepts of host-parasite relationships of oestrids. 相似文献
4.
Evaluation of an antigen capture ELISA for the early diagnosis of Hypoderma lineatum in cattle under field conditions 总被引：1，自引：0，他引：1
Panadero R Vázquez L Colwell DD López C Dacal V Morrondo P Díez-Baños P 《Veterinary parasitology》2007,147(3-4):297-302
An antigen capture or sandwich ELISA (sELISA) was evaluated for the diagnosis of Hypoderma lineatum in cattle under field conditions in northwestern Spain. The kinetics of circulating hypodermin C (HyC) and specific antibodies during the course of natural infestation were determined in a group of 10 Frisian calves. In addition, oesophagi and blood samples were taken from 105 cows at a slaughterhouse in order to compare three methods for the diagnosis of H. lineatum: sandwich ELISA for the detection of the antigen HyC (sELISA), indirect ELISA for the detection of antibodies anti-HyC (iELISA) and the detection of first instars (L1) in the oesophagus. In naturally infested cattle, HyC was present in circulation at low levels during the early and late phases of the infestation. However, in the middle phase, coinciding with the presence of L1 in the oesophagus, two peaks of increased HyC concentration were observed. Specific antibodies increased progressively until the first appearance of larvae in warbles on the back. There was no correlation between antigen or antibody levels and the number of grubs in the back. Prevalence of first instars in the oesophagi of slaughtered cows was 21.9% (23/105). The percentage of cattle that were positive for circulating antigen was slightly higher (24.8%), suggesting the recent destruction of migrating larvae in some animals. However, there was no correlation between the number of L1 and HyC levels. With the iELISA, 79% of the animals were positive to Hypoderma, which means that a high percentage of those animals have been exposed to the parasite but they had no apparent current infestation. The sELISA is a good tool to follow larval development within the host; however, the episodic elevation of HyC levels limits the usefulness of this test for the early diagnosis of Hypoderma under field conditions. 相似文献
5.
为建立牛皮蝇蛆病的抗体检测方法,本研究从纹皮蝇I期幼虫中提取总RNA,采用RT-PCR扩增了Hypodermin C(HC)基因.将该基因片段插入到原核表达载体pET-30a(+)中进行原核表达.获得了31ku以包涵体形式表达的重组HC蛋白.Western blot结果表明表达产物能够与阳性牛血清IgG特异性结合,具有良好的抗原活性.以纯化的重组HC作为包被抗原建立了牛皮蝇蛆病间接ELISA诊断方法,实验确定抗原最佳包被浓度为15.63 μg/mL,血清最佳稀释度为1:80,阳性标准判定为待检血清OD值＞0.256.所建立的诊断方法具有较好的特异性、敏感性和可重复性.应用该检测方法对230份临床血清进行检测,阳性率为20.6％.研究结果表明该间接ELISA方法是一种有效的牛皮蝇蛆病血清学检测方法. 相似文献
6.
Cattle exposed to their third consecutive warble (Hypoderma lineatum and H. bovis) infestation had significantly reduced apparent and accumulative grub populations and produced significantly fewer grubs than animals exposed to their first infestation. These resistant animals had enhanced reactivity to mitogens (concanavalin A (con A) and pokeweed) upon reinfestation and a strong antigen-specific response at 2 months post-infestation. Their responsiveness to con A and antigen was also enhanced at 7 months post-infestation when grubs appeared in the backs, and the response to antigen continued at 10 months post-infestation. Responsiveness to mitogens in previously uninfested animals was similar to the control response throughout the infestation apart from the suppression of the con A response at 7 months post-infestation. These animals finally responded to antigen at 10 months post-infestation. These results suggest that acquired resistance to hypodermosis has a cellular basis with participation of both B- and T-cell components. 相似文献
7.
Ki-hyun Cho Jeongmi Kim Hyun-ah Yoo Dae-hee Kim Seung-yong Park Chang-seon Song In-soo Choi Joong-bok Lee 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(4):503-509
Simple methods for measuring the levels of serum antibody against canine distemper virus (CDV) would assist in the effective vaccination of dogs. To develop an enzyme-linked immunosorbent assay (ELISA) specific for CDV, we expressed hydrophilic extra-viral domain (HEVD) protein of the A75/17-CDV H gene in a pET 28a plasmid-based Escherichia (E.) coli vector system. Expression was confirmed by dot and Western blotting. We proposed that detection of E. coli-expressed H protein might be conformation-dependent because intensities of the reactions observed with these two methods varied. The H gene HEVD protein was further purified and used as an antigen for an ELISA. Samples from dogs with undetectable to high anti-CDV antibody titers were analyzed using this HEVD-specific ELISA and a commercial CDV antibody detection kit (ImmunoComb). Levels of HEVD antigenicity measured with the assays and immunochromatography correlated. These data indicated that the HEDV protein may be used as antigen to develop techniques for detecting antibodies against CDV. 相似文献
8.
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
9.
对临床上采集的244份不同背景的羊血清样本,用纯化的重组N蛋白为包被抗原建立的检测小反刍兽疫病毒(PPRV)抗体的间接ELISA进行检测,运用统计学方法摸清了检测结果的分布规律,并同时用OIE参考实验室抗体检测试剂盒进行检测,结果表明,两种检测方法的符合率为91.73%。利用TG-ROC软件分析了ELISA抗体检测临界值,该试剂盒与国外试剂盒相比,其相对特异性和敏感性分别为98.6%和85.4%。 相似文献
10.
Ahmadu B Lovelace CE Samui KL Mahan S 《The Onderstepoort journal of veterinary research》2004,71(2):161-164
A survey was carried out to define the distribution of heartwater in goats that originated from six districts in communal grazing semi-arid areas of Zambia. A total of 181 samples (40.1%) out of 451 serum samples from adult goats were positive for Ehrlichia ruminantium antibodies after screening using indirect MAP-1B antigen ELISA technique with statistically significant differences (P < 0.01) between the six districts. Out of 1 036 adult goats examined for tick infestation, 105 were infested by ticks, with Amblyomma species being the most dominant tick encountered. Amblyomma variegatum, which is the vector for heartwater transmission in Zambia constituted 42.4% of the tick species, identified. The overall tick infestation rate was 10% while the tick:goat ratio was 2.1:1. Amblyomma variegatum appears to be widespread throughout the study area, as are antibodies to E. ruminantium. 相似文献
11.
重组N蛋白抗原检测PRRSV抗体ELISA的研究Ⅳ.与IDEXX ELISA试剂盒及Western blot的比较 总被引：5，自引：0，他引：5
利用重组N蛋白抗原建立了检测猪繁殖与呼吸综合征病毒（PRRSV）抗体的ELISA方法并组装成试剂盒，将试制的3批试剂盒分别与IDEXX生产的试剂盒及Western—blot进行了符合率试验。试验结果表明，所研制的试剂盒与Western blot的符合率达97．67％以上。对460份临床血清分别用自制的试剂盒和IDEXX公司生产的试剂盒进行检测，其中有37份不相符合，用Western blot对这37份血清进行验证，有35份血清检测结果与自制的试刺盒检测结果一致。由此表明，自行研制的试剂盒，其特异性和敏感性均能满足目前临床上该疫病的流行病学分析或免疫抗体检测。 相似文献
12.
【目的】建立非洲猪瘟病毒（African swine fever virus,ASFV）ELISA抗体检测方法。【方法】以重组截短p72（p72s）蛋白作为检测抗原,通过方阵滴定法,确立ELISA的抗原、待检血清和酶标抗体的最佳工作浓度,优化抗原包被、酶标板封闭、血清/酶标抗体反应及底物显色等工作条件;应用受试者工作特征（receiver operating characteristic,ROC）曲线阈值评价标准,确定方法的阴阳性临界值;检测方法的特异性、敏感性、批内与批间重复性;最后分别用建立的ELISA方法和商品试剂盒检测124份血清,比较两者的阳性检出率,并通过Western blotting验证ELISA的检测结果。【结果】ELISA方法的抗原最佳包被浓度为0.5 μg/mL,待检血清与酶标抗体的最适稀释度分别为1∶100和1∶5 000;反应条件为：抗原于37 ℃孵育1 h后经4 ℃包被酶标板过夜、于37 ℃封闭1 h或室温封闭2 h、待检血清和酶标抗体分别于37 ℃反应60和45 min及加入底物后于室温避光显色20 min;阴阳性血清的判定标准为：当待检血清的D450 nm值≥0.365时,判定为阳性;当D450 nm值＜0.365时,判定为阴性。该方法只与ASFV阳性血清发生特异性结合,与猪瘟病毒、伪狂犬病病毒、猪繁殖与呼吸综合征病毒等病毒抗血清均无交叉反应;能检测到ASFV抗血清中的总蛋白量为0.091~0.153 mg/mL,低于商品试剂盒的最低检测量（0.110~0.554 mg/mL）;批内和批间重复性试验的平均变异系数分别为4.70%与5.125%。对临床血清样本检测时,建立方法和商品试剂盒的阳性检出率分别为75.81%（94/124）和32.26%（40/124）。进一步验证表明,Western blotting与ELISA的检测结果完全一致。【结论】建立了基于ASFV-p72s蛋白的ELISA抗体检测方法,该方法特异、敏感和重复性稳定,能够用于ASF临床诊断与流行病学调查,具有极大的开发应用潜力。 相似文献
13.
以纯化的PRV抗原为包被抗原,优化ELISA反应条件,建立了可检测PRV血清抗体的间接ELISA诊断方法。标定抗原的最佳包被量为0.802μg/mL,血清样品最佳稀释度为1∶100,最佳作用时间为60min,判定标准为OD 450nm值大于0.357为阳性,小于0.296为阴性,在0.296与0.357之间为可疑。该方法检测其他6种常见猪病病毒(CSFV、PCV-2、PRRSV、PPV、JEV、TGEV)的阳性血清均为阴性;与商品化ELISA试剂盒相比较,符合率、敏感性和特异性分别为90.0%、87.1%、92.3%。本研究建立的PRV间接ELISA抗体检测方法具有良好的重复性、敏感性和特异性,为PRV免疫猪群抗体监测、快速诊断和PR流行病学调查提供一种快速、简便的血清学诊断方法。 相似文献
14.
Many commercial enzyme-linked immunosorbent assays (ELISAs) are unable to differentiate antibody responses to different avian influenza virus (AIV) subtypes. Developing an ELISA for specifically detecting the H5 antibody is the purpose of this study. Four monoclonal antibodies (Mabs) were raised using A/duck/Yunlin/04 (H5N2). They were confirmed as being specific to H5. Two of these antibodies showed hemagglutination inhibition (HI) activity using the HI test. Using immunodot blot assays, three Mabs recognized both Eurasian and American H5, whereas the other Mab recognized only the tested Eurasian H5 virus. When testing denatured H5 antigen, one of the Mabs lost its antigen binding activity using Western blotting. For detecting the H5 humoral response in serum, one monoclonal antibody was purified and labeled with horseradish peroxidase to set up a blocking ELISA. Chicken sera that blocked H5 Mab binding by > 29% were considered H5 antibody positive. Inhibition percentages for sera from chickens infected with other AIV subtypes, H1 to H15, were < 29%. This blocking ELISA was used for 478 field chicken serum samples. The results showed that the sensitivity and specificity of this ELISA were 98.3% (232/236) and 95.9% (232/242), respectively. This blocking ELISA could be used specifically for detecting the H5 humoral responses in chickens. 相似文献
15.
F. Borges G. W. Sybrecht G. von Samson-Himmelstjerna 《Equine Veterinary Education》2019,31(3):122-125
A massive infestation with warble fly larvae was observed in a mare in Lower Saxony, Germany. From a herd of 20 horses, only a single mare accidently escaped the routine treatment with macrocyclic lactone in autumn and showed the myiasis infestation next year in January. Eighteen subcutaneous nodules were found on the back (n = 2), ribs (n = 3), flank (n = 5) and croup (n = 8). Deer, the specific hosts of the warble fly Hypoderma diana, was abundant on this farm and some other risk factors for the hypodermiosis are discussed herein. This is the first report of myiasis caused by H. diana in horses in Germany. This massive warble fly infestation in a horse in Germany reported here is important to alert equine health professionals concerning the prevention of this disease in the routine parasite control programme. 相似文献
16.
Giangaspero A Alvinerie M Traversa D Paoletti B Lespine A Otranto D Boulard C 《Veterinary parasitology》2003,116(4):333-343
The prophylactic efficacy of microdoses of injectable and pour-on ivermectin formulations against larval stages of Przhevalskiana silenus was assessed in naturally infected goats in the region of Calabria (southern Italy).Sixty-eight goats from two goat farms were divided into five groups: one group remained untreated, while the other four groups were treated with microdoses of ivermectin (5 and 10 microg/kg injectable formulation and 10 and 20 microg/kg pour-on formulation).The microdoses of ivermectin were fully effective in the treatment of goat warble fly infestation (GWFI) as no larvae emerged from the warbles in the treated groups, while all the larvae emerged in the control groups. Irrespective of the type of formulation used, the difference between the treated groups and the control group was statistically significant (P< 0.001). By contrast, no statistical differences were found between the goats treated with the injectable formulation and those receiving the pour-on applications, and between the two doses of the injectable and pour-on formulations used. Given the plasma concentrations it attains at its lowest dose (0.052 - 0.042 ng/ml for the injectable formulation and 0.030 ng/ml for the pour-on) the injectable formulation seems to offer the most reliable route for the administration of ivermectin microdoses and it is acceptable for milk consumption. The introduction of ivermectin in the early eighties and the use of microdoses in some cases have made it possible to control cattle hypodermosis in large areas of Europe. As with cattle hypodermosis, the administration of ivermectin microdoses in goats is particularly interesting because of the low costs involved and the low levels of residues found in goat milk; it may thus constitute the basis for GWFI control campaigns in areas where the disease is prevalent. 相似文献
17.
Comparative assessment of a double antibody enzyme immunoassay test kit and a triple antibody enzyme immunoassay for the diagnosis of Trichinella spiralis spiralis and Trichinella spiralis nativa infections in swine. 总被引：1，自引：1，他引：0 
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下载免费PDF全文 Enzyme immunoassays using the triple antibody enzyme linked immunosorbent assay (ELISA) with both Trichinella spiralis spiralis and T. spiralis nativa excretory-secretory (ES) antigens and a commercial Trichinella spiralis enzyme immunoassay test kit were carried out on sera from pigs that were infected with light, moderate and high doses of infective T. spiralis spiralis and T. spiralis nativa respectively. Seroconversion occurred in all pigs given infective Trichinella larvae although no trichinae were recovered from pigs given T. spiralis nativa larvae and examined between days 92 and 99 postinfection by pepsin digestion. Anti-Trichinella antibodies were detected in pigs infected with T. spiralis spiralis and T. spiralis nativa by ELISA using either the homologous or heterologous ES antigen. The commercial Trichinella spiralis enzyme immunoassay test kit also detected anti-Trichinella antibodies in both the T. spiralis spiralis and T. spiralis nativa infected pigs. The commercial test kit did not appear to be as sensitive as the triple antibody ELISA since it usually took two to three days longer for seroconversion to be detected by the former procedure. Finally seroconversion occurred more rapidly in swine infected with T. spiralis spiralis than with pigs receiving comparable doses of T. spiralis nativa. 相似文献
18.
This study was aimed to establish an indirect ELISA to detect antibodies against different strains of porcine epidemic diarrhea virus (PEDV). Puried nonstructural protein 7(Nsp7) was used as coating antigen, and the indirect ELISA was established by optimizing the ELISA reaction conditions. The results showed that the optimal reaction conditions were as follow:The amount of coating antigen was 0.20 μg/well, and the coating condition was at 37℃ incubation for 1 h then 4℃ overnight; The working dilution of serum samples and HRP-labelled secondary antibody were 1:300 and 1:10 000, and the incubation time were 2 and 1.5 h, respectively; TMB substrate incubation time was 15 min. Serum sample was determined as positive when its S/P>0.1694 and negative when its S/P<0.1398. The ELISA was specific, reproducible and sensitive. Forty samples of suspected PEDV serum samples were tested by the established ELISA, and the coincidence rate between the ELISA and the commercial kit was 95%. The ELISA established in this study could be used clinically to detect the antibody level of different strains of PEDV, and it also had the potential for early diagnosis of PEDV, providing a basis for the development of effective measures to control PEDV. 相似文献
19.
In order to establish an indirect ELISA method for detection of equine herpesviruses type 4 （EHV4） antibody, the glycoprotein G （gG） protein with specific epitope worked as a detection antigen. After optimizing conditions, the indirect ELISA method was developed successfully，specificity and repeatability tests were determined. The result was that the EHV4 gG only reacted with antibodies against EHV4;but not with antibodies against EHV1; both the intro-batch and inter-batch variation coefficiencies were lower than 10%.Concordance of the indirect ELISA relative to commercial EHV1/4 antibody kit was above 90%.The results indicated that the indirect ELISA method could be used for the detection and epidemiological surveys of EHV4 infection. 相似文献
20.
Evaluation of canine serum for the presence of antiretinal autoantibodies in sudden acquired retinal degeneration syndrome 总被引：2，自引：2，他引：0
OBJECTIVE: To determine the presence of serum antiretinal antibodies in sudden acquired retinal degeneration syndrome (SARDS) affected dogs and the size of the antigen to which these antibodies bind via the use of enzyme-linked immunosorbent assay (ELISA) and Western blot immunoassays. ANIMALS STUDIED: Serum was collected from 13 dogs affected by SARDS and five dogs with normal ocular examinations. PROCEDURES: All serum samples were subjected to ELISA with saline-soluble canine retinal tissue and Western blot analyses with SDS solubilized normal canine retinal tissue as the antigen. Antirecoverin (23 kDa) and antiheat shock cognate (65 kDa) antibodies were used as positive controls for both procedures. Affinity-purified goat antidog IgG and IgM labeled with horseradish peroxidase were used for all clinical samples and goat antirabbit IgG was used as the secondary antibody for the positive controls. RESULTS: ELISA demonstrated antibody reaction with all samples. Western blot immunoassays identified multiple bands in all canine serum samples, as well as in negative controls. Approximate sizes of the bands were 25 and 50 kDa, corresponding to IgG light and heavy chains, respectively. CONCLUSION: No antiretinal autoantibodies were identified in the serum of dogs affected by SARDS as compared to normal canine patients. 相似文献