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1.
The diagnostic test for Tritrichomonas foetus in bulls is microscopic examination of cultured preputial samples. Trichomonads other than T. foetus can be present in a preputial sample. Both a staining technique and a polymerase chain reaction assay were useful in differentiating between T. foetus and another trichomonad observed in samples from virgin bulls.  相似文献   

2.
The traditional diagnostic test for Tritrichomonas foetus involves collection of preputial or vaginal samples followed by culture in a growth media and microscopic examination. Recently, polymerase chain reaction (PCR) techniques have been described for use as a diagnostic assay. The objective of this study was to evaluate a previously described PCR assay for detecting T. foetus in cultured preputial material. The detection limits of the assay for T. foetus organisms in a growth medium, in samples prepared from washing microscope slides, and in preputial material cultured in a growth medium were determined. Preputial samples were collected from 13 bulls uninfected with T. foetus. The PCR assay was able to detect 5 T. foetus organisms in the growth medium and the cultured preputial material. Amplification products were obtained from samples prepared from washes of microscope slides containing as few as 3 visualized organisms. The PCR assay was able to detect organisms in culture at a lower concentration than was possible by direct microscopic examination. This low detection limit may allow the PCR assay to be used to enhance the sensitivity of the current diagnostic test. In addition, the assay could be used to confirm the identification of T. foetus organisms observed by direct microscopic examination when other confirmation techniques, such as staining and phase microscopy, are not practical.  相似文献   

3.
To test the efficacy of a polyvalent Tritrichomonas foetus vaccine, 130 nulliparous heifers were randomly assigned to either receive the test T foetus vaccine or to serve as nonvaccinated controls. The polyvalent test vaccine consisted of a Campylobacter fetus/Leptospira canicola-grippotyphosa-hardjo-icterohaemorrhagiae-pamona bacterine containing 5 x 10(7) killed T foetus/dose. The polyvalent control vaccine consisted of the aforementioned formulation without T foetus. Heifers were administered 2 doses of control or experimental vaccine at 3-week intervals. Heifers were bred to T foetus-infected bulls and their conception and pregnancy rates were determined throughout gestation. In addition, serum samples were analyzed to determine induced concentrations of antitrichomonal antibodies and vaginal secretions were sampled to determine T foetus infection rates in control and vaccinated animals. One week after each of the 15-day breeding periods, 60% (6 of 10) of tested vaccinates and 80% (8 of 10) of tested control animals were T foetus culture-positive. The mean duration of infection of vaccinates was 3.8 weeks (+/- 7.5 days), compared with 5.4 weeks (+/- 7.5 days) of infection for control heifers. All vaccinates developed increased immunofluorescence and serum neutralizing antibody titers following the first immunization, and had additional increases of at least fourfold in response to the second injection. In contrast, no consistent increase in immunofluorescence or serum neutralizing antibodies was observed in control animals. Conception rates were 89.2% for vaccinates and 85.9% for control animals 30 days after breeding and 80 to 90% of these remained pregnant 60 days after breeding.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
Preputial fluids from 567 virgin Angus and Hereford bulls, 1-2 years old, were inoculated into Sutherland medium, and approximately 8.4% produced cultures with a protozoan suggestive of Tritrichomonas foetus. Under brightfield microscopy, large numbers of single-celled motile organisms with multiple anterior flagellae, a posterior flagellum, axostyle, and a visible undulating membrane were detectable. Motility was jerky and rolling, as described for T. foetus. Air-dried smears of cultures stained with Giemsa or Diff-Quick + iodine revealed an organism similar to T. foetus, although somewhat more rounded. Several organisms appeared to have four anterior flagellae. Scanning electron microscopy (5000x) of representative samples revealed four anterior flagellae on most organisms, and an axostyle that was consistently longer than that seen in T. foetus. Using pan-trichomonal primers and T. foetus-specific primers in a polymerase chain reaction (PCR) assay, amplification products of 372bp were detected in all virgin bull isolates, but only with the pan-trichomonal primers. Positive control isolates of T. foetus yielded amplification products of the expected size (372 and 347bp) with the two sets of primers, respectively. We conclude that these protozoa are not T. foetus, and note the similarity of these findings with those reported earlier in North American beef cattle. Because in several countries there is no legal treatment for bovine trichomonosis, veterinarians recommend slaughter of bulls with positive preputial cultures. The existence of easily mis-identified non-T. foetus trichomonads in the bovine prepuce suggests that the current "gold standard" diagnostic test (culture of preputial scrapings or washings) should be augmented with a more specific confirming test, such as the PCR employed in this study.  相似文献   

5.
A number of different culture media have been described for use in the diagnosis of Tritrichomonas foetus infection in bulls, and recently, a commercial culture kit has become available. The objective of this study was to compare the sensitivity of 2 culture-based diagnostic tests for T. foetus in bulls. One test used a commercial kit for transport and culture of the samples. The other test used a thioglycollate transport medium (TFTM) for transport and a modified Diamond's medium (MDM) for culture of the samples. Twenty-one bulls infected with T. foetus were sampled repeatedly. On each sampling day, samples collected from the left and right sides of the bull were tested with one of the 2 diagnostic tests being compared. The effect of the type of diagnostic test on the outcome of the test was evaluated with a chi-square test for the calculated odds ratio. Because repeated tests from the same bull cannot be considered independent measures, unadjusted chi-square tests were adjusted for the effect of clustering by bull. Samples tested using the commercial kit were 6.95 times as likely to be positive as samples tested with a diagnostic test using MDM (P < 0.001).  相似文献   

6.
Bovine herpesvirus 1 (BHV-1) is frequently associated with abortion in naturally and experimentally infected cattle. Most of the virus isolation and immunofluorescent antibody protocols described in the literature for detecting BHV-1 in bovine foetuses are rather laborious, costly and time-consuming. The detection is described of BHV-1 in the tissues of a naturally aborted bovine foetus by a nested PCR assay with no further hybridization procedures.Optimal results were achieved by filtering the foetal tissues on a chromatography column before DNA extraction, by using two pairs of primers in a nested PCR and by evaluating the amplification products on silver-stained polyacrylamide gels.This nested PCR was faster and easier to perform than the virus isolation test. To our knowledge, this is the first time that BHV-1 has been detected in the tissues of a naturally infected bovine foetus by means of a nested PCR. The test seems to be a practical alternative for rapid detection of BHV-1 in bovine foetus.  相似文献   

7.
Trichomoniasis is a sexually transmitted disease of cattle and a large bowel diarrheal disease of cats caused by Tritrichomonas foetus. Recently, other species of trichomonads have been identified from the prepuce of virgin bulls. It is not clear whether these non-T. foetus isolates are common (nor) or is it clear whether they are also present on the prepuce of breeding bulls. To answer these questions, we first developed an immunofluorescent assay (IFA) with T. foetus-specific monoclonal antibodies for comparison with a T. foetus-specific PCR assay. Results showed that all PCR positive isolates were also IFA positive, whether the isolates were from cats or cattle and PCR negative isolates were IFA negative. Bovine non-T. foetus (non-Tf) trichomonad isolates were detected by both assays in 14 virgin bulls, 10 breeding bulls, 21 bulls of undetermined breeding status (presumably breeding bulls) and 2 cows. These isolates from virgin bulls were mostly Tetratrichomonas spp. whereas the non-Tf isolates from most breeding bulls and the two cows were Pentatrichomonas hominis. All T. foetus isolates were from breeding bulls or bulls of undetermined breeding status. This IFA test which discriminates between T. foetus and non-Tf may be useful as a diagnostic assay, since no effective legal treatment is available, bulls positive for T. foetus are culled. With increasing reports of T. foetus large bowel infection in cats, these monoclonal antibodies may also be useful for diagnosis of feline infection. Since two isolates of non-Tf trichomonads were obtained vaginas of breeding cows, it may be that these parasites are sexually transmitted like pathogenic T. foetus.  相似文献   

8.
Accuracy of culture for diagnosis of Tritrichomonas foetus was investigated in 2832 naturally exposed range beef bulls from 124 herds. Preputial fluid samples were inoculated into the culture medium, incubated at 37 degrees C, and daily examined. Diagnostic test was evaluated using Bayesian techniques to estimate sensitivity and specificity without a gold standard. Median posterior test sensitivity was 72.04% (95% probability interval: 58.07-86.38%) and specificity was 95.37% (95% probability interval: 94.07-96.65%). Low diagnostic test accuracy may have resulted from host and/or diagnostic test procedure related factors. Under natural range conditions, more accurate methods for T. foetus diagnostic and repeated preputial samplings of bulls may be necessary on trichomonosis control programs.  相似文献   

9.
OBJECTIVE: To evaluate the efficacy of and optimize a commercially available culture system for sensitive and specific in-clinic culture of Tritrichomonas foetus from cat feces. DESIGN: Prospective study. SAMPLE POPULATION: Samples of freshly voided feces from 117 purebred cats and pure cultures of T. foetus obtained from a cat with chronic diarrhea. PROCEDURE: Optimal conditions for use of the culture system, such as quantity of fecal inoculum (0.025 to 0.2 g) and cultivation temperature (25 or 37 degrees C [98.6 or 77.0 degrees F]), were determined. Specificity of the system was examined by attempted culture of Giardia lamblia and Pentatrichomonas hominis. Sensitivity of the system to detect T. foetus was determined by inoculation of culture system pouches with serially diluted T. foetus suspensions with and without feces. RESULTS: Detection limit of the culture system was 1 and 1,000 T. foetus organisms without and with feces from cats, respectively. Optimal fecal inoculum was < 0.1 g of feces. At 37 degrees C, cultures yielded positive results in 24 hours; organisms remained viable for 1 to 6 days, and bacterial overgrowth was common. At 25 degrees C, cultures yielded positive results in 1 to 11 days; organisms were long-lived, and bacterial overgrowth was uncommon. Neither G. lamblia or P. hominis survived in the culture system. CONCLUSIONS AND CLINICAL RELEVANCE: The culture system was sensitive and specific for culture of T. foetus in feces of cats. Performance was optimal when test kits were inoculated with < or = 0.1 g of freshly voided feces and cultured at 25 degrees C.  相似文献   

10.

Background

In recent years, the protozoan Tritrichomonas foetus has been recognised as an important cause of chronic large-bowel diarrhoea in purebred cats in many countries, including Norway. The aim of this cross-sectional study was to determine the proportion of animals with T. foetus infection among clinically healthy cats in Norway and to assess different risk factors for T. foetus infection, such as age, sex, former history of gastrointestinal symptoms and concurrent infections with Giardia duodenalis and Cryptosporidium sp.

Methods

The sample population consisted of 52 cats participating in three cat shows in Norway in 2009. Samples were examined for motile T. foetus by microscopy, after culturing and for T. foetus-DNA by species-specific nested PCR, as well as for Giardia cysts and Cryptosporidium oocysts by immunofluorescent antibody test (IFAT).

Results

By PCR, T. foetus-DNA was demonstrated in the faeces of 11 (21%) of the 52 cats tested. DNA-sequencing of five positive samples yielded 100% identity with previous isolates of T. foetus from cats. Only one sample was positive for T. foetus by microscopy. By IFAT, four samples were positive for Giardia cysts and one for Cryptosporidium oocysts, none of which was co-infected with T. foetus. No significant associations were found between the presence of T. foetus and the various risk factors examined.

Conclusions

T. foetus was found to be a common parasite in clinically healthy cats in Norway.  相似文献   

11.
Tritrichomonas foetus (T. foetus) is the causative agent of bovine trichomonosis, a sexually transmitted disease leading to abortion (from 1 to 8 months gestation), infertility, and occasional pyometra. The annual losses to the U.S. beef industry are estimated to be in the hundreds of millions of dollars. Currently, the "gold standard" diagnostic test for trichomonosis in most countries is the cultivation of live organisms from reproductive secretions. The cultured organisms can then be followed by PCR assays with primers that amplify T. foetus to the exclusion of all other trichomonad species. Thus, negative results present as null data, indistinguishable from failed PCR amplification during T. foetus specific amplification. Our newly developed assay improves previously developed PCR based techniques by using diagnostic size variants from within the internal transcribed spacer 1 (ITS1) region that is between the 18S rRNA and 5.8S rRNA subunits. This new PCR assay amplifies trichomonad DNA from a variety of genera and positively identifies the causative agent in the bovine trichomonad infection. This approach eliminates false negatives found in some current assays as well as identifying the causative agent of trichomonad infection. Additionally, our assay incorporates a fluorescently labeled primer enabling high sensitivity and rapid assessment of the specific trichomonad species. Moreover, electrophoretic separation of amplified samples can be outsourced, thus eliminating the need for diagnostic laboratories to purchase expensive analysis equipment.  相似文献   

12.
A photometrically-measured indirect fluorescent antibody (IFA) test was developed to measure antibody levels in three heifers vaccinated intramuscularly with two injections (two-week interval) of a vaccine containing formalin-killed Tritrichomonas foetus in oil adjuvant; a separate animal served as a nonvaccinated control. Sera were collected weekly and tested for specific IgG against T. foetus. Antibodies were detectable within two weeks of the initial injection and reached reciprocal titers as high as 7700 as estimated from previously tested reference sera. Titers peaked at six to eight weeks and remained at relatively high levels for the eleven-week study period. The fluorometric assay was easily developed and economical to perform; in addition, it more accurately estimated IgG levels than standard slide IFA tests.  相似文献   

13.
An enzyme-linked immunosorbent assay (ELISA) was developed for detecting antibody to Tritrichomonas foetus using both whole cell antigen (WCA) and membrane protein antigen (MPA). The test was used to detect specific antibody in serum, preputial washings and seminal plasma samples from 7 adult bulls which were vaccinated subcutaneously on 3 occasions with a membrane protein vaccine against T. foetus var brisbane in an oil adjuvant, and from 4 unvaccinated control animals. One month after administration of the third dose of vaccine, vaccinated and control bulls were repeatedly challenged with the live vaccine strain of the T. foetus. A steady increase in serum antibody titre was detected after each inoculation of vaccine when both antigens were used in the ELISA. However, MPA was more sensitive. After challenge, vaccinated bulls developed an increased titre. No specific antibody was detected in control bulls, except in one bull after challenge in which seroconversion was detected. The serum antibody titres of both groups of animals were also measured with the microagglutination test which proved less sensitive than the ELISA. Antibody titres to both antigens, although lower than in serum, were detected in the seminal plasma of vaccinated animals. The control bulls remained non-responsive. No antibody was detected by ELISA in preputial washings from either control or vaccinated bulls prior to challenge. Post-challenge, some of the vaccinated bulls were responsive with both antigens whereas the control bulls remained negative.  相似文献   

14.
OBJECTIVES: To determine the efficacy of ronidazole (RDZ), tinidazole (TDZ), and metronidazole (MDZ) against Tritrichomonas foetus in vitro and of RDZ for treatment of feline naturally occurring or experimentally induced T. foetus infection. ANIMALS: A cat naturally infected with T. foetus infection and diarrhea. Ten specific-pathogen-free (SPF) kittens. PROCEDURE: RDZ, TDZ, and MDZ were tested for activity against 3 different feline isolates of T. foetus in vitro. RDZ then was administered to a naturally infected cat at 10 mg/kg PO q24h for 10 days. SPF kittens were infected orogastrically with feline T. foetus and treated with either placebo or RDZ (10 mg/kg PO q12h for 14 days). Cats with relapsing infection or those receiving placebo were treated subsequently with RDZ (either 30 or 50 mg/kg PO q12h for 14 days). Feces were examined for T. foetus by direct microscopy, culture, and polymerase chain reaction (PCR) testing weekly. RESULTS: Both RDZ and TDZ killed T. foetus at concentrations >0.1 microg/mL in vitro. In the naturally infected cat, RDZ abolished diarrhea and T. foetus infection for 85 days after treatment, at which time infection and diarrhea relapsed. Retreatment with RDZ eradicated diarrhea and T. foetus infection for over 407 days. In experimentally induced infection, RDZ at 10 mg/kg caused initial improvement, but infection relapsed in all 5 cats 2 to 20 weeks after treatment. At 30 or 50 mg/kg, 10/10 cats were negative for T. foetus infection for follow-up durations of 21 to 30 weeks after treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Oral administration of RDZ at 30 to 50 mg/kg q12h for 14 days resolved diarrhea and eradicated infection (on the basis of polymerase chain reaction [PCR] testing) in 1 naturally infected cat and 10 experimentally inoculated cats receiving a different isolate of T. foetus.  相似文献   

15.
OBJECTIVE: To determine the efficacy of tinidazole for treatment of cats with experimentally induced Tritrichomonas foetus infection. ANIMALS: 8 specific-pathogen-free kittens. PROCEDURES: Tinidazole was tested for activity against a feline isolate of T foetus in vitro. Kittens were infected orogastrically with the same isolate and treated or not with tinidazole (30 mg/kg, PO, q 24 h for 14 days). Amoxicillin was administered 28 weeks after completion of tinidazole administration to induce diarrhea. Feces were repeatedly tested for T foetus by use of PCR assay and microbial culture for 33 weeks. RESULTS: Tinidazole killed T foetus at concentrations >or= 10 microg/mL in vitro. In experimentally induced infection, tinidazole administered at 30 mg/kg decreased T foetus below the limit of molecular detection in 2 of 4 cats. Recrudescent shedding of T foetus, as elicited by amoxicillin-induced diarrhea, was diminished in cats that received prior treatment with tinidazole. CONCLUSIONS AND CLINICAL RELEVANCE: Although tinidazole decreased the detection of T foetus and treated cats were resistant to later efforts to incite the infection, inability of tinidazole to eradicate infection in many cats poses a serious impediment to the drug's effectiveness in practice.  相似文献   

16.
OBJECTIVE: To compare sensitivity for diagnosing Tritrichomonas foetus infection in bulls using 2 sampling tools and to calculate negative predictive values for infection. DESIGN: Randomized clinical trial. ANIMALS: 30 Bos taurus bulls naturally or experimentally infected with T foetus. PROCEDURE: Preputial scrapings were obtained once/wk for 6 weeks using an artificial insemination pipette and a metal brush; which tool was used first for each bull was randomly determined. Samples were collected first from the left side of the prepuce and then from the right side and placed in commercially available transport media chi 2 Values and confidence limits were adjusted for effect of clustering of results by bull. RESULTS: Significant differences in sensitivity of results were not found between samples collected using the brush or pipette. Using the pipette, sensitivity was estimated to be 91.6% (95% confidence interval, 84.3 to 95.7%); negative predictive values ranged from 41 to 99% for prevalence of infection of 90 to 5%, respectively. Sensitivity was 88.8% for first sample obtained and 96.1% for second sample obtained. CONCLUSIONS AND CLINICAL RELEVANCE: Collection of preputial scrapings with an artificial insemination pipette or a metal brush and use of a commercially available culture system can provide a sensitive diagnostic test for T foetus infection in bulls. Calculated negative predictive values indicated that 1 or 2 tests would suffice in most clinical situations. For bulls from herds in which T foetus is endemic, 2 to 4 tests/bull may be required to ensure that each bull is not infected.  相似文献   

17.
Tritrichomonas foetus is a serious veterinary pathogen that causes bovine trichomonosis, a sexually transmitted disease that eventually leads to abortion and infertility. T. foetus has a simple life cycle that consists of only a trophozoitic form. During unfavorable environmental conditions, the trophozoites, which are polar and flagellated, can adopt a spherical shape and internalize their flagella. These rounded organisms are known as pseudocysts. Although it is currently assumed that T. foetus pseudocyst formation is reversible and that it represents a response to stressful conditions, there are no reports showing the presence of this form in vivo. For this reason, the aim of this study was to verify whether T. foetus pseudocysts are encountered in naturally infected bulls. Towards this goal, fresh preputial samples obtained from seven mature bulls that were naturally infected with T. foetus were analyzed using complementary techniques, such as video microscopy, fluorescence microscopy, scanning and transmission electron microscopy. The analyses revealed that approximately 55% of the parasites were in pseudocyst form in each preputial sample, whereas approximately 25% of T. foetus displayed pear-shaped bodies. Previous research demonstrated that in vitro T. foetus pseudocysts are able to divide by a budding process. Here, this division mode was observed in approximately 20% of fresh T. foetus obtained from preputial bovine samples. Thus, this study shows that in infected bulls, pseudocysts are present and occur more frequently than the pear-shaped parasites.  相似文献   

18.
Characterization of Tritrichomonas foetus antigens, using bovine antiserum   总被引：3，自引：0，他引：3  
Tritrichomonas foetus antigens were identified, using the serum of an Angus heifer that had been repeatedly immunized with suspensions of 1 X 10(8) organisms in Freund's complete adjuvant. Antibody activity against T foetus was determined by dot-blot analysis, using horse-radish peroxidase-conjugated anti-bovine immunoglobulin to detect bound antibody. The antiserum contained antibodies against surface and flagellar components of live or fixed T foetus, as determined by use of immunofluorescence. The antiserum reacted with approximately 38 proteins in a pool of 55 to 60 components resolvable by polyacrylamide-gel electrophoresis of T foetus extracts.  相似文献   

19.
The development of the ileal Peyer's patches (ilPP) and follicle associated epithelium (FAE) was examined in 30 bovine foetuses ranging from 73 to 271 days of gestation by light and transmission electron microscopic methods. The first primordial ilPP was encountered in the foetus at 164 days of gestation The ilPP were found to have been formed from the aggregation of lymph follicles in the foetus at 227 days of gestation whereas in the foetus at 271 days of gestation the follicular development was observed to have been completed. While the cells in the FAE in the foetus at 164 days of gestation and those older were cuboidal, those of the foetus at 271 days of gestation were columnar. As from the foetus at 227 days of gestation, however, the FAE was found to be composed of uniform lymphoepithelial cells with an increase in the number of intraepithelial leukocytes. In the early stages, whereas the apical surfaces of the FAE cells appeared shorter with microfolds, with advancing age the apical surfaces of the FAE cells were observed to be heterogeneous. Our results suggest that bovine ilPP and FAE cells are histologically and functionally mature before birth.  相似文献   

20.
Zhang W  Deng C  Liu Q  Liu J  Wang M  Tian KG  Yu XL  Hu DM 《Veterinary parasitology》2007,149(1-2):72-76
The first identification of Neospora caninum infection in the tissues of aborted bovine foetuses in China is reported. Aborted foetuses were collected from 16 dams, and 12 of the dams had high serum antibody titres to N. caninum determined using an ELISA test kit. The Nc-5 gene of N. caninum was amplified from DNA samples extracted from brains of four aborted foetuses using a Neospora-specific PCR assay, confirming N. caninum infection in the aborted foetuses. Histology and immunohistochemistry showed thick-walled (3 microm) tissue cyst in 25 microm diameter in the brain of one foetus. Non-suppurative encephalomyelitis, focal haemorrhage, hepatic lesions consisted of lymphocyte infiltration and haemorrhage were also found in the heart and lung of the foetus. Thus, we have confirmed for the first time the infection of N. caninum in aborted foetuses of cattle in the People's Republic of China.  相似文献   

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