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1.
Fresh, diluted semen containing 1.55 X 10(6) cfu/ml of Campylobacter fetus subsp. venerealis was incubated with 500 iu of penicillin, 500 micrograms of streptomycin, 160 micrograms of lincomycin and 300 micrograms of spectinomycin per ml at 35 degrees C for 0, 1, 2, 5, 10, 20 or 40 minutes. The semen was cooled to 5 degrees C, packaged in 0.25 ml French straws and then frozen in liquid nitrogen for 2 weeks. Immediately after thawing and removal of the antibiotics by centrifugation semen samples from each of the seven treatment groups were cultured as for C. fetus. Semen samples were also examined by in-vitro tests for sperm motility prior to and post-freezing. Incubation with the antibiotics for 5, 10, 20 or 40 min prior to freezing reduced the numbers of C. fetus in the semen to non-detectable levels in 38%, 69%, 88% and 100% of samples respectively. The incubated semen showed no significant reduction of sperm motility although fertility trials have not been done.  相似文献   

2.
Campylobacter jejuni abortion in a heifer   总被引：1，自引：0，他引：1  
Campylobacter jejuni was isolated from the lung and stomach contents of an aborted bovine fetus. The bacterial isolate was classified according to morphologic, biochemical, and thermotolerance characteristics as well as sensitivity to antibiotics and biochemical agents. Serotyping was specific for C jejuni and excluded this isolate from the more common bovine causes of campylobacteriosis, C fetus subsp venerealis or C fetus subsp fetus. This report stresses the need for careful speciation of all Campylobacter isolates from aborted fetuses, especially in conditions where routine vaccination has not reduced abortion rates in the herd. Campylobacter jejuni is much more prevalent in causing human infections than is C fetus subsp venerealis or C fetus subsp fetus. Therefore, from a public health standpoint identification is important.  相似文献   

3.
The objective of the present study was to characterize the phenotypic and molecular aspects of Campylobacter fetus strains isolated from bovine herds with reproductive problems. Thirty-one Brazilian field isolates, together with one reference strain of each subspecies of C. fetus, were analyzed. The strains were submitted to phenotypic identification followed by subspecies characterization using the polymerase chain reaction (PCR) and numeric evaluation of restriction fragment length polymorphism (RFLP) separated by pulsed-field gel electrophoresis (PFGE). Phenotypically, 4 isolates (12.1%) were classified as C. fetus subsp. fetus, and 29 isolates (87.9%) were classified as C. fetus subsp. venerealis. However, according to molecular analysis, only 1 isolate (3.0%) was classified as C. fetus subsp. fetus (the reference strain), whereas 32 isolates (97.0%) were considered C. fetus subsp. venerealis. SalI digestion of C. fetus genomic DNA, obtained from the 33 strains, yielded 7-10 DNA fragments ranging in size from 40 to 373kb, with 12 distinct patterns. Furthermore, the numeric analysis by neighbor-joining of the DNA from the 33 strains resulted in a dendrogram in which 2 distinct groups were identified. It was concluded that phenotypic characterization of C. fetus subspecies might lead to erroneous classification of field isolates. Although RFLP-PFGE is a powerful and reliable technique to characterize C. fetus, it has the inconvenience of being time consuming and laborious. Whereas PCR, besides providing rapid results, was found to be reliable and convenient for the characterization of field isolates of C. fetus.  相似文献   

4.
Pathogenicity of 17 Campylobacter isolates for pregnant guinea pigs was investigated. Of 14 isolates, 12 (86%) produced rates of abortion ranging from 13% to 87%. Two isolates did not produce abortion. Reference strains of C fetus subsp venerealis produced abortion in 60% to 87% and C fetus subsp fetus produced abortion in 60% of the guinea pigs. Inoculated organisms were recovered from uterus, blood, liver, kidney, spleen, and gallbladder of the guinea pigs at rates as high as 83% for 2 ovine isolates and as low as 13% for 2 bovine and 1 human isolates. Most isolations were from the uterus. Two avian isolates were not recovered. Within the C jejuni and C coli group, the ovine and the human isolates appear to be more pathogenic. Swine, bovine, and avian isolates were less pathogenic. Seemingly, the pregnant guinea pig was a suitable and practical model for evaluating the pathogenicity of Campylobacter organisms, regardless of their host of origin.  相似文献   

5.
A two-step semen-extending protocol was compared to a one-step protocol in its efficiency in inhibiting growth of Haemophilus somnus, Campylobacter fetus ssp. venerealis, Mycoplasma bovis , and Ureaplasma diversum in experimentally infected semen. In both protocols, the effect of an antibiotic mixture of 500 μg gentamycin, 100 μg tylosin, 300 μg lincomycin, and 600 μg spectinomycin (GTLS) was compared to a mixture of 500 IU penicillin, 500 IU streptomycin, 150 μg lincomycin, and 300 μg spectinomycin (PSLS). The one-step extending method was as effective as the two-step extending method. Both antibiotic mixtures were equally effective in controlling C. fetus . For H. somnus and U. diversum , the PSLS mixture was more effective than the GTLS mixture. It was striking that both antibiotic mixtures had no effect in decreasing the numbers of M. bovis .  相似文献   

6.
The susceptibilities of 40 recent Belgian field isolates of Mycoplasma bovis to 10 antimicrobial agents were assessed. Tiamulin was the most active antimicrobial agent against M bovis, with an initial inhibitory concentration (IIC50) of 0.06 microg/ml, but it is not licensed for the treatment of cattle. All three fluoroquinolones tested (danofloxacin, enrofloxacin and marbofloxacin) were effective against strains of M bovis, and had a minimum mycoplasmacidal concentration (MMC50) less than or equal to 1 microg/ml. Gentamicin was poorly effective, having an IIC50 of 8 microg/ml. Many strains of M bovis were resistant to tylosin, spectinomycin, lincomycin, tetracycline and oxytetracycline.  相似文献   

7.
AIMS: To determine regional prevalences of beef cow herds in New Zealand positive for Campylobacter fetus subsp venerealis antibodies in samples of vaginal mucus tested using an immunoglobulin (Ig) A enzyme-linked immunosorbent assay (ELISA), and to examine the suitability of the IgA ELISA for detecting infection with C. fetus subsp venerealis under field conditions in New Zealand. METHODS: Vaginal mucus samples (n=1,230) collected from beef cow herds (n=125) throughout New Zealand (approximately 10 samples/herd) were tested for antibodies to C. fetus subsp venerealis using an IgA ELISA. Test results were compared between herds classified as having low, medium and high fertility based on pregnancy test results interpreted in relation to the duration of the mating period used. In addition, a small number of samples were collected from dairy cows that were mated using artificial insemination (AI) and had no contact with breeding bulls. The influence of putative risk factors for the spread of venereal disease and the effect of sample quality on the status of herds according to test results was assessed using multivariate logistical regression. Preputial washings from 54 bulls from nine herds classified as low fertility in which mucus samples from > or =3 cows were IgA antibody-positive were cultured for the presence of Campylobacter spp, and isolates of C. fetus subspecies were characterised using a polymerase chain reaction (PCR) test. RESULTS: One or more mucus samples was positive to the IgA ELISA in 70% of all herds tested. The prevalence of IgA antibody- positive individuals was >20% in most regions of New Zealand and did not differ significantly for cows from herds classified as high, medium or low fertility (28%, 26% and 23%, respectively; p=0.39). No relationship was found between mucus antibody status and age of breeding group, herd size, herd fertility, number of herds that female replacements or breeding bulls were sourced from, whether a serving ability test (SAT) was used to assess bulls, or the quality of samples submitted to the laboratory. Campylobacter fetus subsp venerealis was not cultured from any of the 54 bulls sampled. Four other species of Campylobacter and related organisms were cultured, viz Arcobacter cryaerophilus, Campylobacter jejuni, Campylobacter fetus subsp fetus and Helicobacter cinaedi. CONCLUSIONS: The specificity of the IgA ELISA as a diagnostic test for C. fetus subsp venerealis was found to be unsatisfactory under New Zealand conditions. It is possible that an immunological response by cows to Campylobacter species other than C. fetus subsp venerealis caused cross-reactivity in the IgA ELISA. The results do not support the hypothesis that C. fetus subsp venerealis is widespread in New Zealand.  相似文献   

8.
As a result of the high lability and slow growth of Campylobacter fetus subspecies, the laboratory diagnosis of bovine genital campylobacteriosis has always been difficult. This is especially true under South African conditions, where farms are far apart, laboratories are only present in major centres and there are high ambient temperatures. In order to overcome the shortcomings associated with traditional diagnostic methods, the implementation of a molecular assay was sought. This work describes how a previously published PCR assay (MG3F/ MG4R primers) was adapted, optimised and applied in the diagnostic laboratory to test preputial samples directly for the presence of Campylobacter fetus. Field evaluation of the assay revealed an analytical sensitivity and specificity of 85.7% and 99%, respectively. Subsequent genotyping and phenotyping of a diverse collection of South African field isolates revealed that South Africa has an unexpected and previously unreported high incidence of Campylobacter fetus subsp. venerealis biovar intermedius strains. These strains were not identified correctly by the subspecies-specific primer set evaluated. Until such time that cost- effective genotyping methods are available to diagnostic laboratories in South Africa, and other countries with these atypical Campylobacter fetus subsp. venerealis strains, the need for bacterial culture will persist. Identification to subspecies level of isolates at present remains dependent upon a single phenotypic criterion, namely tolerance to 1% glycine.  相似文献   

9.
Experiences, including results of original experimental work on Campylobacter fetus, C. jejuni and C. coli induced diseases of cattle, sheep, dogs, rabbits poultry and men in Hungary are reviewed. Out of 31 cases of abortion in cows 29 (93.5%) were causes by C. fetus subsp. venerealis and only one case each (3.2%) by C. fetus subsp. fetus and C. jejuni, respectively. Out of the 29 strains of C. fetus subsp. venerealis, 26 belonged to serogroup 01 (A) and only 3 to serogroup 02 (B). Campylobacter abortions in sheep flocks were caused in 18 cases (78.3%) by C. fetus subsp. fetus and in 5 cases (21.7%) by C. jejuni. The latter strains belonged to Penner's serogroup 1 (6 strains), 5 (4 strains) and 8 (5 strains), respectively. In scouring dogs 12.7% of the cases were caused by C. jejuni. The same pathogen caused diarrhoea also in young rabbits. Isolated strains belonged to serogroup 2. In cases of Campylobacter hepatitis of laying hens, egg production has been reduced by 8 to 15% for 2 to 3 weeks. Row poultry meat represents often the source of infection for men. The 32 strains of C. jejuni isolated from faecal samples of men affected with diarrhoea belonged to 12 serogroups.  相似文献   

10.
Subcutaneous administration of vaccines prepared from cells of Campylobacter fetus subsp fetus strain A28 to heifers gave substantial protection against infertility due to C. fetus subsp venerealis strain B6. Strains A28 and B6 had different heat-stable antigens and conformed respectively to serotype B and serotype A of Berg et al (1971). The results suggested that the protective antigens were heat-labile antigens common to both strains. Although vaccines prepared from serotype B strains of C. fetus subsp fetus could be used to immunise cattle against vibriosis, the results did not suggest that their use in preference to those prepared from C. fetus subsp venerealis would offer any advantages.  相似文献   

11.
A broth microdilution technique was used to determine the antimicrobial susceptibility of 15 field isolates of Mycoplasma hyorhinis to 10 antimicrobial agents, representative of different classes, and contrasting newer agents to existing ones. For the macrolides, the MIC(90) for tylosin and tilmicosin was 1 and 4 microg/ml, respectively, but was > or = 16 microg/ml for erythromycin. Tetracycline, lincomycin and enrofloxacin each had an MIC(90) of 2 microg/ml. The mycoplasma had similar levels of susceptibility to the aminoglycoside and aminocyclictol classes exhibiting an MIC(90) of 4 microg/ml for gentamicin and 2 microg/ml for spectinomycin. The isolates exhibited high MICs to trimethoprim/sulfamethoxazole with an MIC(90) > or = 16/304 microg/ml. In summary, M. hyorhinis isolates from the US had low MICs against a variety of antimicrobials tested, with the exception of erythromycin and trimethoprim/sulfamethoxazole.  相似文献   

12.
Temporary contamination of the penis and prepuce with Campylobacter fetus subsp. venerealis and Campylobacter fetus subsp. venerealis biotype intermedius may occur when immunised bulls mate with infected heifers. However, 2 experiments showed that this contamination was not a significant cause of genital infection in susceptible heifers that subsequently mated with bulls.  相似文献   

13.
The prevalence of bovine venereal campylobacteriosis (BVC) was investigated in the Lake Chad basin of Nigeria. Preputial washings and cervico-vaginal mucus samples were obtained from 270 cattle presenting a history of abortion and lowered fertility, kept in traditional and institutional farms. All the samples investigated were cultured using standard bacteriological technique. Campylobacter fetus was isolated from six bulls and four cows. In all cattle sampled, the isolation rates were 2.2% for C. fetus subsp. venerealis and 1.5% for C. fetus subsp. fetus; the herd and within-herd prevalence rates for C. fetus were 22.2% and 3.4%, respectively, while the overall active infectivity rate was 3.7%. BVC probably contributes to lowered fertility and abortions found in cattle in the Lake Chad basin of Nigeria, associated more with C. fetus subsp. venerealis than C. fetus subsp. fetus.  相似文献   

14.
A study was conducted to assess the use of ozone (O3) to control pathogens or contaminants of concern to animal breeders and regulatory officials. In separate experiments, samples of fresh bovine semen and Pseudomonas aeruginosa, Escherichia coli, or Campylobacter fetus subsp. venerealis were diluted with antibiotic-free milk (10(6) sperm and 10(6) organisms/mL of diluted semen), exposed in the previous day to a constantly monitored level of 5, 10, 15, or 20 micrograms/mL of O3 for 3-5 min. After 10 min at 30 degrees C, sperm motility was assessed and the samples cooled to 5 degrees C. Two and 18 h after the beginning of cooling, aliquots of each semen sample were evaluated for motility and cultured for organisms. Reductions were observed in P. aeruginosa and E. coli colony counts of 2 logs, and in C. fetus of 5 logs, after exposure for 2 h to O3 at a concentration of 5 micrograms/mL that had a moderate effect on sperm motility (reduction of 20%). Fewer than 100 colonies, i.e., a 4 logs reduction of all bacteria, were counted after dilution with ozonized-treated milk at 20 micrograms/mL of O3. However, this concentration of O3 reduced sperm motility by 50% 10 min after dilution. The results of these experiments indicate that a concentration and exposure time to O3 can be selected to reduce P. aeruginosa, E. coli, and C. fetus in contaminated bull semen diluted with milk while having only minimal effects on sperm motility.  相似文献   

15.
Since the introduction of AI, venereal diseases caused by Tritrichomonas fetus and Campylobacter fetus subsp. venerealis haved been eradicated in The Netherlands. Campylobacter fetus subsp. fetus can cause sporadic abortion and early embryonic death. When natural breeding is practised, venereal diseases must be included in the list of differential diagnoses of fertility problems. A case study of a Campylobacter fetus subsp. fetus infection is described.  相似文献   

16.
The minimum inhibitory concentrations (MICs) of tetracycline, enrofloxacin, tylosin, spiramycin and a lincomycin:spectinomycin 1:2 combination, against 24 Sicilian isolates of Mycoplasma agalactiae, the causative organism of contagious agalactia were determined in vitro by a broth dilution method. Enrofloxacin was the most effective antimicrobial in vitro with a range of MIC values from 0.125 to 0.500 microg/ml and an MIC(50) of 0.203 and MIC(90) of 0.365 microg/ml. Using the MIC(50) and MIC(90) values the remaining four antimicrobials are ranked in order of in vitro effectiveness as follows: tylosin (MIC(50)0.292; MIC(90)0.525 microg/ml) was slightly more effective than tetracycline (MIC(50)0.296; MIC(90)0.533 microg/ml), followed by lincomycin:spectinomycin (MIC(50)0.521; MIC(90)0.938 microg/ml) and spiramycin (MIC(50)1.583; MIC(90)2.850 microg/ml). MIC values above 1.000 microg/ml were obtained using tetracycline, tylosin and spiramycin for some M. agalactiae isolates.  相似文献   

17.
OBJECTIVE: To determine the susceptibility of strains of Pasteurella multocida subsp multocida isolated from lung specimens of pigs with pneumonia to 20 antimicrobials and to evaluate the emergence of resistance to those antimicrobials in Spain during the past 2 decades. SAMPLE POPULATION: 63 isolates recovered from 1987 to 1988 and 132 isolates recovered from 2003 to 2004. PROCEDURE: A broth microdilution method was used to determine minimal inhibitory concentration (MIC) range and values for MIC50 and MIC90. Resistance of a strain to an antimicrobial agent was determined by use of the breakpoint value when available. RESULTS: Isolates were generally susceptible to penicillin, ampicillin, ceftiofur, gentamicin, apramycin, neomycin, spectinomycin, chlortetracycline, erythromycin, tilmicosin, enrofloxacin, and florfenicol, and most isolates were resistant to clindamycin, tylosin tartrate, and tiamulin regardless of the time period. A substantial increase in resistance to sulfa-chlorpiridazine, sulfadimethoxine, sulfathiazole, and trimethoprim-sulfamethoxazole was observed, and a minor increase in resistance to oxytetracycline was also detected. Several multiresistance patterns were observed, most frequently among isolates recovered in the 2003 to 2004 interval. CONCLUSIONS AND CLINICAL RELEVANCE: Ceftiofur, florfenicol, and enrofloxacin are recommended for treatment of infections caused by P multocida subsp multocida in Spain. Increased frequency of resistance to oxytetracycline and sulfonamide drugs may be a contraindication for their use.  相似文献   

18.
Rosaramicin, an agent shown to be effective in vitro against ureaplasma of bovine origin was tested as an additive to bovine semen extender. Although some reduction in semen quality occurred it was still deemed satisfactory for use. In a test involving 41 cows inseminated once at estrus with rosaramicin-treated semen (162 mcg/mL) the nonreturn rate was 24% compared to a calculated average for this semen of 63% (n = 3310). The effect of centrifugation, time and temperature was examined in vitro using a combination of 150 mcg of lincomycin, 300 mcg of spectinomycin and 450 mcg of tylosin against ten strains of bovine ureaplasma. This combination has ureaplasmacidal activity and is suggested as an additive to semen extenders for the control of ureaplasma.  相似文献   

19.
An immunohistochemistry (IHC) procedure for the detection of Campylobacter fetus antigens using an avidin-biotin complex technique was performed on formalin fixed bovine and ovine fetal tissues from 26 natural cases of Campylobacter spp. abortion (four ovine and 22 bovine). The species of Campylobacter isolated included C. fetus ssp. venerealis from 13 bovine fetuses, C. fetus ssp. fetus from two ovine and one bovine fetus, Campylobacter jejuni from seven bovine fetuses, Campylobacter lari from two ovine fetuses and an unspeciated Campylobacter species in one bovine fetus. Histologic lesions identified in the aborted fetuses included placentitis, serositis, pneumonia, gastroenteritis, hepatitis and encephalitis. Campylobacter fetus antigens were identified by IHC in 13 of 13 bovine fetuses from which C. fetus ssp. venerealis was isolated and in two of two ovine fetuses from which C. fetus ssp. fetus was isolated. The IHC stains were negative in tissues from seven bovine fetuses from which C. jejuni was isolated, one bovine fetus infected with C. fetus ssp. fetus, one bovine fetus infected with the unspeciated Campylobacter and two ovine fetuses infected with C. lari. In positive cases, the IHC stain most frequently identified bacteria in the lung and gastrointestinal tract. The C. fetus IHC procedure performed on formalin fixed tissues is a practical tool for the diagnosis of natural cases of ovine and bovine abortion caused by C. fetus.  相似文献   

20.
Objective To evaluate a polymerase chain reaction assay for identification of Campylobacter fetus and differentiation of the defined subspecies.
Design Characterisation of bacterial strains by traditional phenotyping, polymerase chain reaction, a probabilistic identification scheme and macrorestriction profiling using pulsed field gel electrophoresis.
Procedure The results of identification of 99 bacterial strains as determined by conventional phenotyping or by poly-merase chain reaction were compared. Two of these were type strains of C fetus subsp fetus and C fetus subsp venerealis ; the remaining strains were field isolates putatively identified as C fetus . In cases where the subspecies identity was disputed, isolates were identified by means of a probabilistic identification scheme and by macrorestriction profiling.
Results The agreement between strain identities initially suggested by traditional phenotypic methods and the PCR assay was found to be 80.8%. The polymerase chain reaction proved to be a reliable technique for the species and subspecies identification of C fetus ; equivocal results were obtained in only two instances. Initial misidentifications by conventional phenotyping methods were attributed to methodological differences used in various laboratories.
Conclusion Our results indicate that misidentification of C fetus i n routine diagnostic laboratories may be relatively common. The PCR assay evaluated gave rapid and reproducible results and is thus a valuable adjunctive method for the identification of C fetus and subsequent subspecies differentiation.  相似文献   

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