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1.
A commercial flock of Suffolk and Suffolk-cross breeding rams was monitored for 5 years in an effort to control epididymitis caused by Brucella ovis. Scrotal palpation, semen evaluations, and vaccination against B ovis were used the first 3 years. Serologic evaluation (complement fixation and ELISA) was added the fourth year, and bacteriologic culturing was added to the program the fifth year. Semen culturing in the fifth year revealed 9 (37.5%) of 24 rams were actively excreting B ovis; 6 of those 9 rams were seronegative. Neither semen quality nor the presence of WBC in the semen were dependable criteria to detect these seronegative carriers. In spite of the high percentage of B ovis excretors, few clinical signs of epididymitis were detected in the flock during the last 3 years of the study. It was hypothesized that vaccination protected rams against the clinical disease but not the carrier state. The importance of culturing semen for assessment of a control program was emphasized.  相似文献   

2.
Rams shedding Brucella ovis in semen but without palpable abnormalities of the epididymides were treated with long-acting oxytetracycline for 15 days and dihydrostreptomycin for 7 days (n = 9) or conventional oxytetracycline and dihydrostreptomycin (n = 9) for 7 days. Nine rams were not treated. More treated rams were considered to have satisfactory breeding soundness examination results at posttreatment weeks 3, 7, 12, and 19. Nontreated rams continued to shed B ovis in semen. After treatment, B ovis was not recovered from 78% of rams given long-acting oxytetracycline and dihydrostreptomycin or from 89% of rams given conventional oxytetracycline and dihydrostreptomycin. At week 21, all rams were euthanatized, and specimens of the testes and epididymides were bacteriologically cultured for B ovis. Brucella ovis was not recovered from the testes of rams or from the epididymides from rams not shedding the organism in the semen. In one treated ram, B ovis was recovered from the semen but not from other tissues. All rams remained ELISA-positive, with the exception of 2 treated rams that ceased shedding B ovis in semen immediately after treatment was started; both these rams became ELISA-negative on the last examination at week 19.  相似文献   

3.
A clinical palpation and semen smear examination of 647 rams submitted to the Regional Veterinary Laboratory during 1967 revealed that 42 (6,5%) of these animals had clinical epididymitis or orchitis, 6 (0,9%) showed other types of genital lesions and 98 (15,1%) suffered from subclinical genital infection. A. seminis and A. seminis-like organisms were isolated from semen specimens of 18 out of 35 rams with clinical epididymitis or orchitis, 25 out of 33 rams with subclinical infection and none out of 13 rams which showed no neutrophils in their semen. On 4 stud farms where Elberg Rev. 1 vaccine was meticulously applied and the complete absence of Brucella ovis infection was established, of a total of 327 rams examined, 10 (3,6%) were found to be clinically and 72 (22,0%) subclinically affected. A. seminis was isolated from 5 out of 6 of these rams with clinical lesions and 10 out of 15 of those which showed evidence of subclinical infection.  相似文献   

4.
Testicles from rams in flocks experiencing ram epididymitis in Idaho and eastern Oregon were cultured. Twenty-six breeding rams from 6 flocks were cultured and only Brucella ovis was isolated. Virgin rams (65) harbored numerous species of small fastidious gram-negative rods, including Actinobacillus actinomycetemcomitans, Haemophilus spp, Moraxella spp, and Pasteurella spp. Thus, there appeared to be 2 separate disease entities, dependent on sexual experience of the animal.  相似文献   

5.
The measures taken to eradicate Brucella ovis infection from a naturally infected flock of 64 rams are described. Lesions of epididymitis were detected in 18 rams, all of which gave either positive or suspicious reactions in the complement fixation test. A further 20 rams gave serological reactions in the complement fixation test. Subsequently, semen was collected from 14 of these 20 rams and B. ovis was cultured from the semen of all 14 rams. Serum samples from two rams failed to react in the complement fixation test. However, they were identified as infected with the aid of an enzyme-linked immunosorbent assay and the subsequent culture of semen samples. It is suggested that, when eradicating B. ovis infection from ram flocks, the enzyme-linked immunosorbent assay be used in addition to both the complement fixation test and the physical examination. Using a combination of tests as described can increase the likehood of an earlier eradication of B. ovis infection.  相似文献   

6.
Palpation of the testicles and epididymides was used to determine the prevalence of ram epididymitis (RE) in Utah range flocks over a 5-year period. Of 62 range flocks examined, 58 had rams with palpable lesions. A comparison was made of prevalence by right vs left testicle involvement, but no significant difference was found. Culling all rams with palpable lesions from the flock progressively reduced the annual incidence, but did not eliminate RE from any flock. Semen and specimens of reproductive tract tissue were obtained from representative flocks for bacterial culture. Brucella ovis was found commonly in range flocks, but was not isolated from RE-affected rams in virgin, ram-producing flocks. In the ram-producing flocks, a gram-negative, pleomorphic rod-type organism was found. It was concluded that RE should be considered as 2 disease entities, based on the finding of 2 causative organisms and the management systems under which those organisms are found. Brucella ovis was the major cause in persistently infected range flocks, whereas the gram-negative pleomorphic rod-type organism is the apparent cause of RE in virgin, ram-producing flocks.  相似文献   

7.
The sensitivity and specificity of a PCR assay with primers derived from the insertion sequence IS6501 was compared with that of bacteriological culture and serological tests for the diagnosis of Brucella ovis infection in rams. No amplifications were detected with DNAs from the strains phylogenetically related to Brucella and from the seven bacterial species considered as the main etiologic agents of epididymitis in rams. In addition, the specificity of the PCR was 100% when testing semen samples from Brucella-free rams. The comparison of the semen culture and PCR results from 192 semen samples tested, showed a proportion of agreement of 0.91 between both tests. The PCR-based test described has sensitivity similar to that of semen culture and could be used as a complementary test for the direct diagnosis of Brucella ovis in semen samples of rams.  相似文献   

8.
Economics of Brucella ovis control in sheep: epidemiologic simulation model   总被引：1，自引：0，他引：1  
The epidemiology and economics of Brucella ovis control in a hypothetical, commercial sheep flock (100 rams and 2,500 ewes) were investigated. The investigation consisted of an epidemiologic simulation model, reported here, and a decision-tree analysis, reported in a companion paper. The epidemiologic model was designed to simulate the transmission and persistence of B ovis in a ram flock during the mating season as well as the nonmating (isolation) season. A constant contact rate was selected for the nonmating season and a varying contact rate was selected for the mating season to reflect changes in numbers of ewes in estrus. These contact rates were used to evaluate all possible combinations of 5 control alternatives for flock infection rates ranging from 0% to 38%. Vaccination was found to be more effective as a control strategy when the prevalence of flock infection was high (greater than 15%); however, it did not substantially reduce B ovis transmission when the prevalence of flock infection was low (less than 10%). The effect of increasing vaccine efficacy from 40% to 80% had minimal effect on incidence of new cases. The speed with which B ovis could be eradicated depended on the initial prevalence of infection and the screening tests used (palpation, semen testing for leukocytes, and ELISA). All combinations of screening tests verified the usefulness of palpation. Simulation model results indicated that it may be feasible to eradicate B ovis from flocks with moderate to high (10% to 38%) prevalence of infection by culling on the basis of 2 sequential tests.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

9.
Commercial ram flocks in the Tamworth area of northern New South Wales were surveyed to estimate the proportion of flocks, and rams, infected with Brucella ovis. The flock prevalence (percentage of flocks containing seropositive rams) of 9.1% for Merino flocks was significantly lower than that for British-breed flocks (43.8%, p=0.006) and mixed-breed flocks (46.7%, p=0.017). The mean flock prevalence over all flock types was 32.9%. These estimates were supported by data obtained from diagnostic testing for brucellosis carried out during the previous 6 years. The seroprevalence in rams was 10.8% overall, 2.5% for Merinos, 19% for Border Leicester and 26% for Dorset rams. Within infected flocks, the estimated prevalences were 21%, 65% and 67% for Merinos, Border Leicester and Dorset rams respectively. The seroprevalence in Merino rams was significantly lower than that for both other breeds (p<0.001) for all flocks and in infected flocks. There was no apparent association between age and serological status, or age and the prevalence of epididymitis.  相似文献   

10.
A simple enzyme linked immunosorbent assay (ELISA) was developed for the serological diagnosis of Brucella ovis infections in rams. Serums from brucellosis accredited-free flocks and flocks known to be infected with B. ovis were tested and the results correlated with warm complement fixation (CF) test and bacteriological examination of semen. Both the ELISA and the CF test detected 0.5% false positive reactions in rams from clinically negative flocks. However the ELISA detected significantly more positive reactors in infected flocks and the CF test failed to detect some rams excreting B. ovis. The ELISA proved to be a valuable test in eradicating brucellosis from infected flocks.  相似文献   

11.
The eradication of Brucella ovis from a commercial flock of 36 Romney rams was complicated by four infected rams remaining undetected despite four successive flock examinations using the complement fixation test. These four rams were subsequently tested using an enzyme-linked immunosorbent assay and a gel diffusion test and shown to be infected by semen culture. All four rams could have been identified as infected at the initial test if the enzyme-linked immunosorbent assay had been used in addition to the complement fixation test. Although gross evidence of epididymitis was found in only one ram at necropsy, three had histological lesions of epididymitis and all four had a seminal vesiculitis.  相似文献   

12.
The complement fixation test (CFT), the enzyme labelled immunosorbent assay (ELISA) and the gel diffusion precipitin test (GD) were compared, for the diagnosis of Brucella ovis infection in rams. The sensitivities of the tests in 109 rams which were shedding B. ovis in their semen were: CFT 96.3%; ELISA 97.2%; GD 91.7%. The specificities of the tests in 141 rams from non-infected flocks were: CFI 99.3%; ELISA 98.6%; GD 100%. Predictive values of the three tests were measured in 285 rams from infected flocks. Thirty-eight percent of these rams were shedding B. ovis in their semen. Predictive values of positive tests were: CFT 75.5%; ELISA 66.7%; GD 72.5%. Predictive values of negative tests were: CFI 97.1%; ELISA 97.6%; GD 93.8%.  相似文献   

13.
Brucellosis in sheep, caused by Brucella ovis, is primarily a chronic infectious disease of rams with epididymitis as its most characteristic lesion. Six hundred rams from an infected farm were clinically and serologically examined once a year, over a 3-year period. An increase from 2.1% to 6.3% in the prevalence of animals serologically positive to B. ovis occurred over the 3 years. However, the prevalence of rams with lesions in the reproductive tract declined from 14.2% to 6.5% in the third year following one year of strict culling of clinically affected and rams that were serologically positive for B. ovis. Clinical lesions found in the 179 affected rams fell into two main categories: rams with epididymitis and rams with affected lymph nodes. These results suggest that the prevalence of the disease relates mainly to the sexual activity of the animal and not to age in itself. A single cull based on the results of clinical examination and serological test results was unable to decrease the prevalence of B. ovis in an extensive Corriedale sheep flock.  相似文献   

14.
The serological response to Brucella ovis and the shedding of the organism in semen was followed for a period of 13-14 months in 42 naturally infected rams. Most rams remained chronically infected and excreted the organism in their semen throughout the investigation. B. ovis was isolated from 87.9% of the semen samples from the infected rams. The most common sites from which B. ovis could be isolated at necropsy were the epididymides and accessory sexual glands. In one ram the organism was isolated from lung, spleen, kidney and iliac lymph nodes. Three rams ceased to shed B. ovis in their semen during the course of the investigation. Seventy-five (11%) of 686 sera from infected rams were negative in the complement fixation test (CFT) although 76% and 77% of CFT-negative sera were positive in the gel diffusion precipitin test (GDT) and enzyme labelled immunosorbent assay (ELISA) respectively. The high incidence of CFT-negative infected rams was due to the selection for the investigation of many rams with histories of negative or vacillating CFT titres. Sera from five rams which never shed B. ovis in their semen reacted erratically in the three serological tests. The five rams were from heavily infected flocks and were kept in contact with infected rams throughout the investigation.  相似文献   

15.
The efficacy of Brucella Melitensis Rev 1 vaccine (Rev 1) for the prophylaxis of Brucella ovis ram epididymitis was evaluated. Twenty-nine 3-month-old rams were vaccinated with 2 X 10(9) Rev 1 and 14 were revaccinated with 5 X 10(8) at 14 months of age. Six rams remained unvaccinated as a control group. All rams were challenged with 5 X 10(8) B. ovis at 21 months of age. Before being slaughtered 8 weeks later, only one vaccinated ram developed epididymitis while four of the six control rams developed testicular alterations. Genital and selected extragenital organs and lymph nodes were removed at slaughter and inoculated on selective media. B. ovis was isolated from 26.6% of the vaccinated rams, 21.4% of the revaccinated rams and 100% of control rams. Portions of epididymis, testes and vesicular glands were also used for pathological studies. More severe lesions were observed in control rams than in vaccinated ones. In conclusion, these results show that vaccination of young lambs, followed or not by revaccination, is a suitable method for the prophylaxis of B. ovis infection of rams.  相似文献   

16.
Ovine brucellosis in alberta   总被引：2，自引：1，他引：1       下载免费PDF全文
Two parallel surveys of rams from Alberta sheep flocks were conducted to determine the presence of infection with Brucella ovis. In a retrospective study over a period of 24 months, using complement fixation test, 12 flocks out of 142 tested were considered infected. In another 17-month survey of slaughter rams by serology and culture methods 11 flocks out of 124 were found to be infected. The overall prevalence of ovine brucellosis was 8.6% of the flocks tested which represented 12.5% of the estimated sheep flocks in Alberta. Up to 67% of rams in infected flocks reacted to complement fixation test.

The complement fixation test was evaluated for its efficiency in the diagnosis of ovine brucellosis and compared with a limited number of an enzyme-linked immunosorbent assay (ELISA) results and clinical criteria. The complement fixation test as well as ELISA identified all culture positive rams. Both serological tests appeared satisfactory for the diagnosis of B. ovis epididymitis when the results could be interpreted in the light of flock history and clinical findings.

  相似文献   

17.
An enzyme-linked immunosorbent assay (ELISA), using an autoclave-extracted soluble antigen, for the detection of serum antibodies to Brucella ovis in sheep was developed. The test seemed to be both sensitive and specific, on the basis of the control groups studied. The antigen showed no deterioration in prepared plates stored at -70 C for up to a year. The ELISA was used in conjunction with palpation of rams for epididymal lesions as a means to detect and control B ovis infection in a naturally infected flock. All rams were evaluated by the ELISA. At the time that the first blood sample was obtained, all positive and suspicious reactors were removed. With subsequent blood sample collections, only the positive reactors were removed. Brucella ovis was not isolated from any rams during the following year, and none of the mature breeding rams developed epididymal lesions.  相似文献   

18.
Twenty-four rams inoculated with Brucella ovis by conjunctival and preputial routes were treated with a long-acting oxytetracycline alone or in combination with dihydrostreptomycin sulfate. The combined treatment eliminated Brucella ovis from 11 of 12 (91.6%) treated rams. Only 4 of 12 (33.3%) rams treated with oxytetracycline alone were bacteriologically negative. Neither treatment resolved clinical epididymitis in 2 rams affected before treatment. Many rams had pathologic lesions in the epididymis and ampullae, which limited the efficacy of antibiotic treatment.  相似文献   

19.
AIM: To determine the effects of Brucella ovis infection on semen characteristics of 16-month-old red deer stags (Cervus elaphus). METHODS: At monthly intervals during March, April and May, semen was collected using electro-ejaculation from 9 yearling red deer stags that had been artificially infected with B. ovis 3 months previously. In March, semen was also collected from 6 non-infected stags from the same peer group for comparison. Semen was evaluated for gross appearance, percentage of sperm showing forward motility, sperm morphology and sperm density/ml of semen, and the presence of white blood cells was determined. In addition, at the time of semen collection, the epididymes of each stag were palpated and lesions recorded. RESULTS: Grossly visible purulent material was present in semen from 6/9 infected stags and the percentage of sperm showing forward motility did not exceed 20% in any of these samples. Increased numbers of white blood cells and cellular debris were evident in semen from 8/9 infected stags. Compared with non-infected stags, sperm motility in semen from infected stags was significantly reduced (p<0.05). There were no differences in percentage of morphologically normal sperm between groups, but infected stags had more detached sperm heads present in semen than non-infected stags (p<0.05). Only 2 of the infected stags had lesions of epididymitis evident on scrotal palpation. CONCLUSIONS: B. ovis infection is likely to have a detrimental effect on stag semen quality. While there was variation between individual animals, overall sperm motility was decreased and semen from infected stags had increased numbers of white blood cells and detached sperm heads. CLINICAL RELEVANCE: The fertility of breeding stags may be reduced if they are infected with B. ovis and this possibility should be considered when investigating reproductive problems of deer.  相似文献   

20.
Breeding-soundness examination (BSE) and eradication of Brucella ovis infection in rams are critical components of flock-health programs. The aims of this retrospective, cross-sectional study were to describe the results of BSE in a large sample of rams in the Western USA and to determine the association between BSE outcome and the semen collection method (penis manually extended vs. retained in the preputial cavity), ram body-condition score (BCS), the presence of ulcerative posthitis, and the size of the flock of origin. We evaluated the first BSE in a given year for rams from Colorado, Wyoming, and Utah, USA, from 2000 through 2007. Breeding-soundness examination consisted of physical examination, scrotal circumference and BCS measurement, semen collection by electroejaculation, and microscopic examination of semen motility, morphology, and leukocyte concentration. We assigned a reason for failure to each failed BSE and used multivariable logistic and Poisson regressions to measure associations between ram and flock variables and the risk or reason for failure on BSE. A non-random, owner-selected subset of rams was tested for antibodies to B. ovis by serum indirect ELISA (iELISA). The Rogan-Gladen corrected B. ovis seroprevalence was measured. Of the 14,667 BSEs performed on 11,804 rams, 29.0% were classified as "failed;" the most common reason for failure was substandard semen parameters (43.8%). Breeding-soundness examinations were more likely to have been categorized as failure for inflammatory causes when performed on rams from medium-sized flocks (OR 1.6; 95% CI 1.1, 2.3) and large flocks (OR 1.4; 95% CI 1.0, 1.9) (P=0.02), suggesting that larger flocks are at higher risk of contagious diseases. The adjusted seroprevalence of B. ovis antibodies among tested rams in this study was 10.0%. Of 233 rams seropositive to B. ovis, 125 (53.6%) were subclinical, a finding that supports the importance of this test in ram BSE. We found that emaciation in rams was associated with an increased risk of BSE failure from substandard semen parameters (P<0.001), but ulcerative posthitis and the semen collection method were not (P=0.09 and 0.34, respectively). However, collection of semen with the penis retained in the preputial cavity resulted in greater odds of leukospermia relative to semen collection with the penis extended (OR 4.1; 95% CI 2.9, 5.9; P<0.001), presumably from contamination of the semen sample with preputial leukocytes. For ram BSE, therefore, semen collection with the penis manually extended from the sheath is recommended to limit leukocyte contamination of the sample.  相似文献   

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