Cryptosporidiosis associated with bacterial enteritis in a goat kid

A 7-day-old male Nubian-Alpine crossbred goat was examined because of listlessness, anorexia, and diarrhea. The presumptive diagnosis was severe enteritis. Large numbers of Clostridium perfringens and a non-pathogenic heavily encapsulated Escherichia coli were isolated from the feces. Cryptosporidium parvum was identified on the qualitative fecal examination. The kid improved after treatment with fluids and antibiotics.     

Detection of Cryptosporidium oocysts in soil samples by enzyme-linked immunoassay

An ELISA protocol was adapted for detection of Cryptosporidium parvum oocysts in soil samples and the limit of detection of the test was determined. A modified indirect antigen capture ELISA protocol was developed using monoclonal antibodies against the oocyst outer wall. The accuracy of the ELISA was compared to spiked soil samples and measured in terms of sensitivity and specificity of the test. The performance of the ELISA was evaluated in field soil samples and measured using the kappa-statistics. Similarly, the performance of the ELISA was compared to the concentration flotation method, to a modified concentration flotation method and to a commercial ELISA (ProSpecT) in field fecal and soil samples.The limit of detection of the test was selected to be 10,000 oocysts/g. At this limit of detection, the ELISA had a sensitivity of 95% and specificity of 100%. The agreement between the ELISA and the modified flotation-concentration method in detecting Cryptosporidium oocysts in soil samples was 32% (kappa=0.32). The ELISA had the same relative sensitivity (82%) in comparison to both the flotation and ProSpecT in determining Cryptosporidium-infection status of an animal. The kappa-statistics was 0.26 for both tests. The developed ELISA proved to be a valuable diagnostic test for detecting oocysts in soil samples and has a potential application in determining the infection status of animals.     

Detection of rotavirus in faecal specimens with a monoclonal antibody enzyme-linked immunosorbent assay: Comparison with polyclonal antibody enzyme immuno-assays and a latex agglutination test

Monoclonal antibodies have been produced against the 81/36F strain of rotavirus. One of them, was chosen as diagnostic reagent: it showed high ELISA reactivity with all the bovine, human and porcine rotavirus strains tested and reacted with VP6, structural protein product known to support the common rotavirus antigen.

A sandwich ELISA procedure using the chosen monoclonal as “capture and detecting” antibody was performed to detect rotavirus in faecal samples from experimentally inoculated newborn calves: it always gave a negative response with meconium and a positive response for the stool specimens which rotavirus have been isolated. This assay was compared with Enzygnost and Slidex Rota Kit tests and with a non-commercial sandwich ELISA test using polyclonal antibodies: it showed more sensitivity than the agglutination test and was as sensitive as the other two tests to detect rotavirus in routine diagnostic material. The test evaluated showed no equivocal results.     

Detection of Cryptosporidium parvum oocysts in environmental water in Hokkaido, Japan

Control of cryptosporidiosis is important in public health. Rivers that are polluted with Cryptosporidium and drinking water that is treated for drinking water production from polluted rivers could result in the waterborne disease of cryptosporidiosis. We carried out an epidemiological study of natural water supplies in Hokkaido, one of the largest dairy prefectures in Japan. To detect Cryptosporidium oocysts in environmental water, the filtration method was used for 28 samples, which were collected from 10 rivers. A method adapted from the United States Environmental Protection Agency (U.S. EPA) filtration method using a cartridge filter has been used for the collection of samples. Oocysts were separated from a pellet by discontinuous sucrose gradient method. Twelve samples were collected from 10 rivers and parasites were purified by iron (III) flocculation method. Cryptosporidium parvum oocysts were identified with the immunofluorescence antibody technique using DIF kit (Cellabs Pty. Ltd., Sydney/Australia). We detected Cryptosporidium oocysts in 6 out of 10 rivers sampled. Fifty percentage (14/28) of the samples were Cryptosporidium-positive. The average number of Cryptosporidium oocysts was 16.73/100 L (max. 80/100 L).     

Serologic evaluation of cattle inoculated with Toxoplasma gondii: comparison of Sabin-Feldman dye test and other agglutination tests

Six cows and 6 calves were each inoculated with 100 or 100,000 Toxoplasma gondii oocysts. Serum samples were analyzed, using the Sabin-Feldman dye test (DT), indirect hemagglutination test, latex agglutination test, and the modified direct agglutination test (MAT). Antibody titers in cows were lower than in calves. In the cows, DT titers increased briefly during the first month after inoculation, after which the titers were negative; however, T gondii was isolated from the tissues of 4 cows. Indirect hemagglutination and latex agglutination titers were generally less than 1:256. The MAT titers increased to 1:1,024 during the first month after inoculation. In 5 of the 6 cows, the MAT titers persisted. The 6th cow had a preinoculation MAT titer of 1:2,000 for 3 to 6 months. Therefore, the DT was not useful in serologic surveys for T gondii in cattle; the MAT was the most sensitive test and may be useful in the diagnosis of T gondii infection in cattle.     

牛、羊布鲁氏菌病试管凝集试验与微量凝集试验检测方法的比较

血清学检测方法因其快速、安全、高效等特点被广泛应用于布鲁氏菌病的检测和诊断。本文通过对保存的226份牛、羊血清样品同时使用试管凝集法与微量凝集试验进行检测并比较分析其在诊断中的意义。结果显示,微量法与试管法两者的符合率为97.79%,两种检测方法无统计学差异。但微量法的阳性检出率要高于试管法,同时由于微量法具有操作简便、快捷及结果判定更为直观、简单等优点,因此,微量凝集试验更适宜在我国基层布鲁氏菌病大量样本监测、诊断中推广应用。     

Clinical evaluation of a cryptococcal antigen latex agglutination test for diagnosis of cryptococcosis in cats

A commercial cryptococcal antigen latex agglutination test was used to evaluate sera from 20 cats with cryptococcosis and 184 cats without cryptococcosis. Cryptococcal antigen was detected in the sera from 19 of 20 cats with cryptococcosis. Antigen was not detected in sera from any of the cats without cryptococcosis. The test had sensitivity of 95% and specificity of 100%.     

猪伪狂犬病血清抗体检测——Dot-ELISA法和乳胶凝集试验法的比较

Ｄｏｔ -ＥＬＩＳＡ即斑点酶联免疫吸附试验 ,是检测猪伪狂犬病血清抗体的一种常用方法 ,此方法操作比较简便 ,反应快速 ,结果特异准确。对于猪伪狂犬病抗体的检测 ,最近又有人建立了乳胶凝集试验 ,此方法更为简单易行 ,只需一块玻片、一支吸管 ,将待检样品 (血清、全血和乳汁 )置于玻片上 ,加乳胶抗原一滴 ,搅拌并摇动 ,2～ 5分钟内即可观察结果。为了弄清两种方法对猪伪狂犬病血清抗体的检测结果是否一致 ,笔者采用两种方法 ,对采自本市猪场的2 48份猪血清同时进行了抗体检测 ,两种方法的结果基本一致 ,差别只在于对弱抗体血清的反应程度…     

Detection of a small number of Cryptosporidium parvum oocysts by sugar flotation and sugar centrifugation methods

Detection rates from the samples including a small number of Cryptosporidium parvum oocysts were compared between the sugar flotation and the sugar centrifugal flotation methods. As the results, the oocysts were detected from 70 and 80 of 100 samples including 6.0x10(2) and 1.0x10(3) oocysts per 1 ml by the flotation method, respectively, whereas from 52 and 53 of the same samples by the centrifugal flotation method. Therefore, it was considered that the flotation method is the most suitable method for the detection from samples including a small number of Cryptosporidium oocysts. It is also suggested that results of the sugar flotation method were reliable for samples including more than 1.0x10(3) oocysts/ml.     

Hammondia heydorni oocysts in the faeces of a greyhound in New Zealand

AIMS: To identify oocysts found in faecal material of a greyhound. METHODS: Polymerase chain reaction (PCR) and DNA sequencing were used to study genomic DNA isolated from oocysts purified from faeces of a greyhound. RESULTS: Database searches with the DNA sequences obtained showed they were derived from Hammondia heydorni. A species-specific PCR was developed to detect H. heydorni DNA. CONCLUSIONS: Light microscopy in conjunction with PCR and DNA sequencing definitively identified the presence of H. heydorni oocysts in faeces of a greyhound. CLINICAL RELEVANCE: This study confirms the presence of H. heydorni in New Zealand and indicates the need to correctly identify similar oocysts from dogs, rather than assume they are Neospora caninum.     

Comparison of staining and concentration techniques for detection of Cryptosporidium oocysts in cat faecal specimens.

Modified Ziehl-Neelsen (MZN), auramine-phenol (A-P) and fluorescein isothiocyanate-labelled (FITC-labelled) monoclonal antibody (MAb) techniques were compared for detection of Cryptosporidium parvum oocysts in cat faecal specimens inoculated with known numbers of C. parvum oocysts. Of the three techniques, the FITC-labelled MAb technique detected more oocysts than the MZN and A-P techniques (P < 0.05), but A-P was more efficient than MZN (P < 0.05). Comparison of sucrose flotation, zinc sulphate (ZnSO4) flotation and formol-ether (F-E) sedimentation techniques revealed that F-E was the most efficient of the three (P < 0.05) for concentration of C. parvum oocysts from cat faecal specimens. On average, the F-E technique recovered 37% of oocysts from the original sample, whereas the sucrose and ZnSO4 flotation techniques recovered 33% and 11%, respectively. The findings of this study suggest that MZN and A-P staining are both useful for screening C. parvum oocysts in cat faecal materials containing 10(6) oocysts or more, but FITC-labelled MAb should be used when the number of oocysts is low. Also, the F-E sedimentation technique is recommended for concentrating oocysts in cat faecal specimens.     

Detection of anthelmintic resistance: a comparison of mathematical techniques

Anthelmintic resistance has become an increasing problem particularly to gastrointestinal tract nematodes and appropriate methods are required to detect this phenomenon so the correct action can be taken. This paper compares a number of mathematical techniques that are used to analyse data. The negative binomial distribution is a mathematical distribution used to model aggregated data and hence is suitable to model the intensity of parasite burden and the magnitude of the faecal egg counts. Maximum likelihood techniques are utilised to exploit this mathematical distribution to analyse the magnitude of the faecal egg count reduction and decline in the worm burden in response to anthelmintic treatment. Data from experimental groups of sheep described in the accompanying paper are used. In addition, simulated data sets of faecal egg counts were created using a random number generator following appropriate negative binomial distributions. The results demonstrate this statistical model can detect evidence of anthelmintic resistance with a faecal egg reduction test that otherwise might require a slaughter trial to demonstrate. In addition, the simulated data sets confirm that there is a significant probability of failure to detect low anthelmintic efficacy with commonly used mathematical techniques. Consequently, the use of maximum likelihood mathematical techniques with a negative binomial statistical model would aid in the early detection of anthelmintic resistance using faecal egg count reductions and result in a lower probability of inappropriately assigning an anthelmintic as effective.     

Adaptation of a latex agglutination tube test for diagnosis of Mycoplasma hyopneumoniae swine pneumonia

A tube latex agglutination test (LAT) for diagnosis of Mycoplasma hyopneumoniae swine pneumonia was developed. In pigs inoculated with M. hyopneumoniae, LAT antibodies were generally detected 2–3 weeks post-inoculation, which was 1 week or more before complement-fixing antibodies were first detected in the corresponding pigs. Correlation of LAT results and gross and microscopic lung lesions of corresponding pigs revealed that LAT titers persisted after the pneumonic lesions had resolved.Latex agglutination titers in pigs exposed by contact with M. hyopneumoniae inoculated pigs were demonstrated 4–12 weeks post-contact.Latex agglutination antibodies were detected up to 48 weeks post-inoculation in pigs inoculated with M. hyopneumoniae and this was similar to the duration of detectable indirect hemagglutination titers. Complement-fixation titers, however, were demonstrated no longer than 28 weeks post-inoculation in corresponding pigs.Evaluation of repeatability of LAT results revealed some variation of LAT titers of sera titered on four different occasions.Sera from pigs inoculated with other swine mycoplasmas, including M. hyosynoviae and M. hyorhinis, did not react in the M. hyopneumoniae LAT. In addition, no detectable titers were demonstrated in the M. hyopneumoniae LAT using sera from pigs infected with Metastrongylus spp., Ascaris suum, or in sera from pigs vaccinated with any of four commonly used swine vaccines.