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1.
Summary

In the period from August 1981 to April 1983, 10243 random samples of urine from slaughtered cattle were inspected for the presence of the stilbene derivatives diethylstilbestrol (DES), dienestrol (DE), and hexestrol (HEX). Fast screening of all samples was performed by radioimmunoassay (RIA) with prior clean‐up column chromatography. In this screening, 216 samples were indicated for confirmatory analyses by combined high performance liquid chromatography‐gas chromatography‐mass spectrometry (HPLC‐GCMS) on account of an immunochemical response equivalent to 1 μg/ 1 DES or more. The presence of DES was confirmed in 184 samples, DE in 5 samples and HEX in 14 samples. In the remaining 13 samples no stilbene derivative could be confirmed.

From the results in 1984, after the introduction of the Meat Inspection Act, it is concluded that the use of stilbene derivatives in cattle in the Netherlands has dropped almost to zero. Of 4558 samples investigated, only 6 (0.13%) were indicated as ‘stilbene’ positive. The presence of DES was confirmed in 2 samples and DE in 4 samples.  相似文献   

2.
Summary

The second part of an experiment is described in which 20 one year old bulls were injected with diethylstilbestrol (DES) dipropionate containing preparations. Analysis of DES content was performed in several tissues, such as the injection site, diaphragm muscle, psoas muscle, liver, kidney and bile. In the injection site appreciable amounts of DES were found. Measurable amounts of DES were also found in liver and kidney until 4 weeks after injection. In bile, DES concentrations were even higher than those in urine, and were well correlated with DES concentrations in urine.

Implications for screening purposes are discussed.  相似文献   

3.
Abstract

Serum samples from 15 yearling channel catfish Ictalurus punctatus convalescing after experiencing enteric septicemia of catfish were distributed into three representative serum pools, each containing equal volumes of serum from five fish. Serologic recognition of each pooled serum sample against Edwardsiella ictaluri and Escherichia coli whole cells and against secretory antigen (exoantigen) derived from E. ictaluri was measured by enzyme-linked immunosorbent assays (ELISA). Serum samples were purified by affinity chromatography with a heterologous Ra,-mutant lipopolysaccharide that was derived from rough Salmonella typhimurium TV 119 and was covalently bound to an agarose matrix. Removal of antibodies recognizing the lipopolysaccharide by cross-reactive affinity purification caused significant decreases in serologic recognition of E. ictaluri (P < 0.10) and E. coli (P < 0.01) whole cells; however, serologic recognition of the E. ictaluri-specific exoantigen was not significantly decreased. These results indicate that serologic recognition of the exoantigen is highly specific and that cross-reactive immune responses recognizing homologous gram-negative core antigens will not cause false-positive test results when the specific capture ELISA is used to detect exposure to E. ictaluri  相似文献   

4.
In this experiment 20 one year old bulls received a single intramuscular injection of the anabolic preparation diethylstilbestrol dipropionate (DES-DP) (an oil preparation or an emulsion). Four animals received a corresponding placebo. The application of DES-DP to bulls caused characteristic histological alterations in the peripheral glandular epithelium of the prostate, which could be observed until four weeks after treatment. The value of histological investigation as a screening method was, however, limited by the occurrence of only few metaplastic lesions and a rapid recovery. By contrast, immunohistochemistry using a polyclonal cytokeratin antiserum K40 appeared to be a specific and very sensitive method to detect oestrogen-induced lesions in the prostate. In only two animals, six weeks after injection with the DES-emulsion, false-negative results were obtained, demonstrating the potential value of this screening method. The excretion of DES in the urine and faeces was monitored using radioimmunoassay following chromatographic purification of the urine and faeces extracts. The excretion of DES in urine was faster for animals of the oil group. The DES content in urine decreased to the 1 microgram/l level after 42 days (emulsion group) or 70 days (oil group). The excretion in faeces was comparable to that in urine. After day 21 the excretion patterns of the two excreta were indistinguishable.  相似文献   

5.
Summary

The new combination of isocratic high performance liquid chromatography (HPLC) with on line UV spectrum detection via a diode array configuration has been applied to the detection and identification of anabolics present in application sites of cattle.

Combination of the characteristic retention time in the HPLC chromatogram and a comparison of the full spectrum between 190–400 nm of the anabolic components with that of a standard resulted in a very reliable identification. By means of this method 117 samples of application sites were investigated for the presence of anabolic residues. Of the xenobiotic anabolics, 19‐nortestosterone (NT) was found most frequently (in 96 cases), whereas diethylstilbestrol (DES) was found in only 11 cases.

In all samples the identification of NT and DES was confirmed by high resolution gas chromatography‐mass spectrometry (GCMS).  相似文献   

6.
己烯雌酚及其免疫检测技术概述   总被引:4,自引:0,他引:4  
己烯雌酚是一种人工合成的雌性激素,因其残留对人体和环境有明显的危害,对相关产品中己烯雌酚残留的检测受到世界各国共同关注。本文对国内外己烯雌酚的免疫检测方法(酶联免疫法、放射免疫法、荧光免疫分析等)及免疫检测中的关键问题进行了阐述。  相似文献   

7.
Abstract

AIM: To investigate polymeric nanoparticles as an oral delivery system for protein biocontrol agents for control of the brushtail possum, Trichosurus vulpecula.

METHODS: Insulin-loaded poly(ethyl 2-cyanoacrylate) (PECA) nanoparticles were prepared using interfacial polymerisation, and characterised for size, zeta potential, and efficiency of encapsulation of insulin. In-vitro release of insulin-loaded PECA nanoparticles was quantified using reverse-phase highpressure liquid chromatography (HPLC). The in-vivo pharmacokinetics of insulin in PECA nanoparticles was investigated following I/V administration, and when injected directly into the caecum alone or in conjunction with the permeation enhancer EDTA. Blood samples were collected at intervals from ?5 to 180 minutes, and the concentration of insulin in plasma was quantified using a radioimmunoassay (RIA) validated for possum plasma.

RESULTS: Poly(ethyl 2-cyanoacrylate) nanoparticles were produced with a uniform particle size of 200–300 nm, and the mean entrapment of insulin was 78%. In-vitro release of insulin from the PECA nanoparticles was controlled, although incomplete, and approximately 30% of the insulin remained entrapped. The bioavailability of insulin when administered in a PECA nanoparticulate formulation injected directly into the caecum was <1%, and was not increased by addition of the permeation enhancer.

CONCLUSIONS: The nanoparticulate formulations investigated as part of this study resulted in low bioavailability of the peptide insulin in the brushtail possum.  相似文献   

8.
In the period from August 1981 to April 1983, 10243 random samples of urine from slaughtered cattle were inspected for the presence of the stilbene derivatives diethylstilbestrol (DES), dienestrol (DE), and hexestrol (HEX). Fast screening of all samples was performed by radioimmunoassay (RIA) with prior clean-up column chromatography. In this screening, 216 samples were indicated for confirmatory analyses by combined high performance liquid chromatography-gas chromatography-mass spectrometry (HPLC-GCMS) on account of an immunochemical response equivalent to 1 microgram/1 DES or more. The presence of DES was confirmed in 184 samples, DE in 5 samples and HEX in 14 samples. In the remaining 13 samples no stilbene derivative could be confirmed. From the results in 1984, after the introduction of the Meat Inspection Act, it is concluded that the use of stilbene derivatives in cattle in the Netherlands has dropped almost to zero. Of 4558 samples investigated, only 6 (0.13%) were indicated as 'stilbene' positive. The presence of DES was confirmed in 2 samples and DE in 4 samples.  相似文献   

9.
Background: Canine visceral leishmaniasis (CVL) is a worldwide parasitic zoonosis caused by Leishmania (Leishmania) infantum around the world. Canids are the definitive hosts and sand flies the intermediate hosts.

Objective: To test the hypothesis that a new species-specific primers (Lch14:Lch15, targeting a multiple alignment for L. infantum kDNA minicircle) is an efficient diagnostic tool for L. infantum.

Methods: The presence of L. infantum DNA was assessed in blood samples of 69 stray dogs using the conventional PCR (cPCR) and quantitative PCR (qPCR). Additional 50 lymph nodes and 50 bone marrow samples (positive and negative samples for parasitological tests) from dogs from endemic and nonendemic areas for CVL were also used.

Results: L. infantum strains, and all positive lymph node and bone marrow samples for parasitological test gave positive results for cPCR and qPCR, presenting analytical sensitivity of ~100 parasite mL?1. For the blood samples, 40/69 (58%; CI 95%; 46%–69%) resulted positive for L. infantum in both tests. All positive samples were confirmed by sequencing.

Conclusion: This study showed the importance of the specific detection of L. infantum based on species-specific primers by molecular techniques, highlighting the application as a confirmation method in epidemiological studies and to adopt the best control measures.  相似文献   

10.
Although incorporating proteases into sperm medium is considered the most effective procedure to eliminate camel semen viscosity, it drastically affects viability, morpho-functional properties and, hence, fertilization potential of spermatozoa. The present work aimed at evaluating adequacy of employing magnetic nanoparticles-based sperm purification technique for eluting impaired and apoptotic camel spermatozoa from cryopreserved semen doses following protease-based semen liquefaction. Thirty cryopreserved semen doses (50 x 106 sperm/straw) representing the following liquefaction treatments: control (untreated), 0.1 mg/ml papain or 5 U/ml bromelain were used (n = 10 straws per treatment). Immediately after thawing (38°C for 40 s), sperm concentration of each straw within treatment was readjusted to 15 x 106 sperm/mL by dilution in PBS (37°C). Sperm physical and cytological properties were then assessed (non-purified semen). Thereafter, each specimen was subjected to lectin-functionalized DNA-defrag magnetic nanoparticles sperm purification, and the same sperm traits were re-evaluated after undergoing purification (purified semen). Sperm DNA fragmentation level within each group, prior to and after magnetic nano-purification, was also determined by fluorescent imaging. The results showed a dramatic improvement (p < .05) in post-thaw motility (%), viability (%), normal sperm (%), intact acrosome (%) and HOST-reacted (%) spermatozoa in protease-liquefied semen following sperm magnetic nano-purification. Additionally, the highest (p < .05) DNA fragmentation level was recorded in all cryopreserved semen groups prior to purification, whereas the lowest (p < .05) was observed in the protease-treated specimens after magnetic nano-purification. These results indicate that protease-based semen liquefaction prior to cryopreservation in conjunction with magnetic nano-purification post-thawing holds potential for reducing the proportion of damaged and dead spermatozoa, hence improving camel sperm fertilization competence.  相似文献   

11.
ABSTRACT

Aims: To compare detection by real-time PCR of DNA from Mycoplasma bovis on mucosal swabs taken from the palatine tonsillar crypt and the mainstem bronchi of clinically asymptomatic calves after slaughter.

Methods: We compared the sensitivity of mucosal swabs taken from two sites: the palatine tonsillar crypt and the mainstem bronchi. Paired samples were taken post-mortem at slaughter from 55 clinically well calves from an infected herd and were tested by real-time PCR for the presence of M. bovis-specific DNA.

Results: Mycoplasma bovis DNA was detected in 51 palatine tonsillar crypt swabs (92.7 (95% CI?=?82.4–98.0)%) and seven mainstem bronchial swabs (12.7 (95% CI?=?5.3–24.5)%). All seven calves with positive mainstem bronchial swabs also had positive palatine tonsillar crypt swabs.

Conclusions: When compared to mucosal swabs of the mainstem bronchi, mucosal swabs of the palatine tonsillar crypt were seven times more sensitive for the post-mortem detection of M. bovis DNA. The viability of detected M. bovis was not assessed, because any cattle carrying viable or non-viable M. bovis DNA were determined to be a potential risk to eradication. Palatine tonsillar crypt mucosa may be a useful anatomical site for real-time PCR detection of M. bovis DNA in naturally infected calves. More work is needed to define the persistence and viability of M. bovis at this anatomical site.

Clinical relevance: The results of this study helped form the basis of surveillance tools used in M. bovis control and eradication efforts. Familiarity with these results may help veterinarians better communicate with their clients about the science behind the eradication efforts.  相似文献   

12.
Abstract

Surface-exposed outer membrane proteins (OMPs) of Edwardsiella ictaluri were isolated by selective solubilization of inner membrane proteins from total membrane preparations. Purification of biotin-labeled, insoluble, surface-exposed proteins using streptavidin columns was performed, and single-dimension sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) showed four major OMPs, with apparent molecular weights of 22, 31, 59, and 72 kilodaltons (kDa). Purified surface-exposed proteins corresponded to proteins isolated from total outer membrane preparations resolved by SDS–PAGE, showing that surface-exposed proteins are within the outer membrane fraction and can be successfully isolated using affinity purification. Polyclonal antiserum against these surface-exposed OMPs was produced in New Zealand white rabbits, and protein recognition was determined using in-gel Western analysis. Rabbit antisera recognized three of the four protein bands (22, 31, and 59 kDa). The produced antisera blocked invasion of cells from fathead minnow Pimephales promelas by virulent E. ictaluri, showing that at least one of these proteins is involved in initial bacterial–host cell interactions.  相似文献   

13.
Abstract

The variation in progesterone secretion during the luteal phase and pregnancy in blue fox vixens was analyzed. Progesterone was measured in blood plasma once or twice a week using radioimmunoassay. The material was allocated into three groups; five mated, but barren, blue fox vixens, six mated vixens with implantation zonès in the uterus, but no cubs at parturition, and 26 normally parturient vixens. The progesterone profiles for the three different groups of females showed a steady increase in progesterone immediately after mating. Maximum values were observed on days 8–12 of pregnancy. Then the progesterone levels decreased gradually until delivery around day 52. The levels of progesterone were found to be significantly different (P<0.05) between non-pregnant and pregnant females from day 22 after mating. The plasma progesterone level seems to be affected by the presence of conceptuses.  相似文献   

14.
Background

Toxoplasma gondii is a common protozoan parasite among all mammals, in particular small ruminants, worldwide. Traditional husbandry can be a major risk factor for infection of sheep and goats with this parasite.

Objectives

The present study aimed to determine the current status of the prevalence for T. gondii in livestock of Qazvin Province.

Methods

In this cross-sectional study, the sera of 455 sheep and 375 goats were examined to detect anti-Toxoplasma IgG antibodies by using in-house indirect ELISA.

Results

Overall, 33.62% (153/455) of sheep and 36.41% (130/375) of goats were positive for anti-Toxoplasma IgG antibodies with no statistically significant difference. The prevalence rate of T. gondii among the sheep of Qazvin County was significantly higher than in Abyek and Abhar counties (p < 0.001).

Conclusions

The results of the present study indicate that the prevalence of T. gondii in sheep and goats of the study area is high. Therefore, the meat of the animals reared in this area can be a potential source of human infections by this parasite.

  相似文献   

15.
Abstract

Lipopolysaccharide (LPS) was purified from 40 isolates of Edwardsiella ictaluri by two methods: (1) enzyme digestion and hot aqueous phenol extraction and (2) enzyme digestion and gel exclusion chromatography. Purified LPS was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and by immunoblot analysis. Both methods of purification yielded smooth LPS as evidenced by a ladderlike pattern of more than 40 LPS bands. With silver staining, both low- and high-molecular-mass LPS bands were seen. Lower-molecularmass LPS stained more intensely than higher-molecular-mass LPS bands, indicating a preponderance of lower-molecular-mass LPSs. Lipopolysaccharide bands from the 40 isolates migrated similarly within SDS-PAGE gels, indicating a high degree of structural similarity among the isolates examined. The ladderlike array was more easily seen with immunoblot analysis than with silver staining of SDS-PAGE gels. Additionally, immunoblot analysis revealed a high degree of antigenic similarity among the 40 isolates.  相似文献   

16.
Abstract

A kit for a solid-phase enzyme immunoassay (SOPHEIA®) of cortisol in human sera was evaluated and validated for measuring cortisol in plasma of rainbow trout Oncorhynchus mykiss. The accuracy of the SOPHEIA was demonstrated by the recovery of exogenous cortisol concentrations of 25, 50, 100, and 250 ng/mL in charcoal-stripped fish plasma. The amounts (mean ± SE) recovered from triplicate samples were 29.9 ± 2.75, 47.5 ± 3.41, 101.7 ± 12.08, and 232.0 ± 11.06 ng/mL, respectively. The intra- and interassay coefficient of variation (CV = 100 × SD/mean) for cortisol levels in undisturbed fish (26.6 ± 1.18 ng/mL) were 14 and 10%, respectively. The intra- and interassay CV for elevated cortisol levels in stressed fish (330.8 ± 19.90 ng/mL) were 8 and 13%, respectively. Cross-reactivity determined for nine steroids in teleostean fish was negligible. Cortisol concentrations in serial dilutions of pooled fish plasma were parallel to the standard curve. Sensitivity (minimum detection limit) was 3.04 ng/mL. The SOPHEIA compared favorably to radioimmunoassay measurements of cortisol (r = 0.98; P < 0.001).  相似文献   

17.
Background: Brucella abortus, the major causative agent of abortion in cattle and a zoonotic pathogen, needs to be diagnosed at an early stage. Loop-mediated isothermal amplification (LAMP) test is easy to perform and also promising to be adapted at field level.

Objective: To develop a LAMP assay for specific and rapid detection of B. abortus from clinical samples of cattle.

Methods: LAMP primers were designed targeting BruAb2_0168 region using specific software tool and LAMP was optimized. The developed LAMP was tested for its specificity with 3 Brucella spp. and 11 other non-Brucella spp. Sensitivity of the developed LAMP was also carried out with known quantity of DNA. Cattle whole blood samples and aborted fetal stomach contents were collected and used for testing with developed LAMP assay and results were compared with polymerase chain reaction (PCR).

Results: The developed LAMP assay works at 61 °C for 60 min and the detection limit was observed to be 100-fold more than the conventional PCR that is commonly used for diagnosis of B. abortus. Clinical sensitivity and specificity of the developed LAMP assay was 100% when compared with Rose Bengal plate test and standard tube agglutination test. SYB® green dye I was used to visualize the result with naked eye.

Conclusion: The novelty of the developed LAMP assay for specifically detecting B. abortus infection in cattle along with its inherent rapidness and high sensitivity can be employed for detecting this economically important pathogen of cattle at field level as well be exploited for screening of human infections.  相似文献   

18.
ABSTRACT

Aims: To determine the presence of infection and co-infection of Plasmodium lineages in introduced birds at translocation sites for the North Island saddleback (Philesturnus rufusater), to investigate their role as Plasmodium spp. reservoirs.

Methods: Blood samples were collected from introduced bird species, with a special focus on blackbirds (Turdus merula) and song thrushes (Turdus philomelos), at six locations in the North Island of New Zealand that were the origin, or translocation sites, for North Island saddleback. Where available, blood smears were examined, and blood samples were tested using nested PCR with subsequent sequence analysis, for the presence of Plasmodium spp.

Results: Of the 55 samples tested using PCR analysis, 39 (71%) were positive for Plasmodium spp., and 28/40 (62%) blood smears were positive for Plasmodium spp. Overall, 31 blood samples were from blackbirds with 28/31 (90%) samples positive for Plasmodium spp. Six distinct avian Plasmodium lineages were identified, including three cosmopolitan lineages; Plasmodium vaughani SYAT05 was detected in 16 samples, Plasmodium matutinum Linn1 in 10 samples and Plasmodium elongatum GRW6 in eight samples. Mixed infections with more than one lineage were detected in 12 samples. Samples from two Australian magpies (Gymnorhina tibicen) were positive for Plasmodium. sp. lineage MYNA02, previously not identified in New Zealand.

Conclusions and clinical relevance: This is the first report from New Zealand in which specific Plasmodium spp. mixed infections have been found in introduced birds. Co-infections with several cosmopolitan Plasmodium lineages were identified, as well as the first report in New Zealand of an exotic avian Plasmodium sp. lineage, in Australian magpies. Whilst the role of introduced birds in maintaining and spreading pathogenic avian malaria in New Zealand is unclear, there is a potential infection risk to native birds, especially where distributions overlap.  相似文献   

19.
Background: Besides the anticoccidial drug resistance problem, increasing consumer concerns about food safety and residues have propelled the quest for alternative prevention and control strategies amongst which phytotherapy has gained appeal due to a renewed interest in natural medicine.Objective: The objective was in vivo screening of four phytochemicals/extracts and a fungal immunomodulatory protein (FIP) against an Eimeria acervulina infection in broilers.Animals and methods: Four phytochemicals/extracts (extract from Echinacea purpurea, betaine (Betain?), curcumin, carvacrol (two different doses)), and a recombinant FIP from Ganoderma lucidum cloned and expressed in Escherichia coli were investigated for their anticoccidial potential. The experiment was conducted in a battery cage trial with 54 cages of eight birds each. Broilers infected with E. acervulina (a low and high infection dose of 104 and 105 sporulated oocysts, respectively) and treated with the phytochemicals/extracts or the FIP were compared with broilers treated with the anticoccidial salinomycin sodium (Sacox®) and with an untreated uninfected and an untreated infected control group. Coccidiosis lesion scores, body weight gains and oocyst shedding were used as parameters.Results: The results showed a coccidiosis infection dose effect on the mean coccidiosis lesion scores. The phytochemicals/extracts and the FIP failed to reduce coccidiosis lesion scores and oocyst shedding, while salinomycin efficiently controlled the E. acervulina infection and enabled significantly higher body weight gains.Conclusion: In conclusion, the selected phytochemicals/extracts and the FIP did not reduce the lesions of an experimentally induced E. acervulina infection.  相似文献   

20.
AIMS: To undertake disease surveillance for Chlamydia psittaci in native birds as part of a pilot study to examine pathogen diversity on Hauturu-o-Toi/Little Barrier Island. To retrospectively review the Massey University post-mortem database to determine previous cases of avian chlamydiosis in New Zealand.

METHODS:Mistnetting of forest birds was conducted across an elevational gradient on Hauturu-o-Toi/Little Barrier Island. Minitip culture swabs were used to collect cloacal samples from native birds. These swabs were screened for Chlamydia family DNA using two PCR methods. Positive results were sequenced. A retrospective review of the Massey University post-mortem database of all avian cases from 1990 to 2011 was conducted.

RESULTS:Ten native birds including four bellbirds (Anthornis melanura), three rifleman (Acanthisitta chloris), two hihi (Notiomyces cincta), and one whitehead (Mohoua albicilla) were sampled and one otherwise healthy female hihi was positive by both PCR screening methods for Chlamydophila. Sequencing confirmed 99–100% genetic similarity to C. psittaci. A retrospective review of the Massey University post-mortem database revealed no previous diagnoses of avian chlamydiosis in wild native New Zealand birds although it has been detected in captive parrots, and wild and captive exotic pigeons.

CONCLUSIONS:This is the first report of the detection of C. psittaci from a wild native bird in New Zealand. The bird was a Passeriforme from an endangered species that was captured free-living on Little Barrier Island. The incidence of avian chlamydiosis in native birds in New Zealand appears to be very low, based on the retrospective review of the post-mortem database.

CLINICAL RELEVANCE: It is unlikely that avian chlamydiosis is a significant problem for hihi population health. The detection of this organism has greater significance for other more susceptible species on Little Barrier Island and for human health, particularly for conservation workers involved in wildlife translocations. It further suggests that passerine birds may be a reservoir for C. psittaci in New Zealand ecosystems.  相似文献   

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