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1.
Complement fixation tests using three B. ovis antigen preparations in warm fixation tests (WCFT) and cold fixation (CCFT) tests were done on 541 ram sera. Semen samples from the same rams were examined culturally to identify B. ovis excretors. The CCFT, using an antigen prepared by heat extraction of B.ovis cells, had a sensitivity of 97% in 124 rams which were shedding B.ovis. The specificity was 99% in 144 rams from non-infected flocks. Seventy-seven per cent of 156 rams which reacted to this test were shedding B. ovis in their semen. Tests with other antigens were inferior in sensitivity and/or specificity. The WCFT gave lower titres than CCFT. Vaccination caused large numbers of false positive reactions in 4 flocks. 相似文献
2.
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 lymphnodes. 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. ovisin 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
3.
Abstract Sir:- A project to investigate the efficacy of the complement fixation test (CFT) for the diagnosis of Brucella ovis infection in rams has recently been completed. The investigation was undertaken by field and laboratory staff of the Division of Animal Health and several practitioners. The results of CFT's done with 3 antigens by waim and cold fixation methods (WCFT and CCFT) were correlated with results of cultures done of semen from the same rams. It is our aim to publish a full report in this Journal at a later date. In view of the widespread interest in the subject some of the important findings are summarised below: -
? Semen and blood samples were collected from 541 rams in 40 flocks. -
? The type of antigen which has been used for a number of years in New Zealand was unsatisfactory. The CCFT using this antigen had a sensitivity of only 85% in 124 rams which gave positive semen cultures. These rams came from 16 infected flocks. -
? The CCFT using the best of the 3 antigens proved to be a remarkably reliable test. In the same group of infected animals mentioned above, 120 of the 124 infected rams had positive or suspicious CFT's. The sensitivity of the test was therefore 97%. The specificity was > 99% in 144 rams in 16 uninfected flocks. Only 1 suspicious titre was found in the uninfected group. -
? In 4 flocks in which B. ovis was never isolated, 18 of 58 sera gave positive or suspicious reactions. Recognition of this type of 'problem flock' is therefore important. A history and clinical picture which does not agree with serological results should always be thoroughly investigated. Semen should be collected from an appropriate number of cases for bacteriological examination. It is suspected that at least some ‘problem flocks’ may contain unreported vaccinated animals. Further investigation of ‘problem flocks’ will be an aim of the Animal Health Division in the future. 相似文献
4.
One hundred and thirty eight rams were allocated to four experimental groups. An inactivated Br. ovis vaccine was administered either once by the intraperitoneal route (1 i/p), twice by the intraperitoneal route (2 i/p), or twice by the subcutaneous route (2 s/c), and the last group was left unvaccinated. They were then challenged by the intravenous inoculation of between 123 and 1.23 × 10 8 live Br. ovis bacteria. The number of rams that succumbed to infection within the four groups was 4/35 (11%) for the 2 s/c, 7/33 (21%) for the 2 i/p, 9/35 (26%) for the 1 i/p and 18/35 (51%) for the unvaccinated rams. Vaccination reduced the number of rams that succumbed to experimental challenge and although there were differences between the vaccinated groups, these were not statistically significant. Following challenge, unvaccinated rams were the first to excrete Br. ovis in their semen; three weeks following inoculation. Next, those vaccinated by either one or two doses by the intraperitoneal technique began to excrete the organism (five weeks) and then finally those rams vaccinated twice by the subcutaneous route (seven weeks). 相似文献
5.
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
6.
A study was conducted to estimate the seroprevalence of Brucella ovis infection in rams in the Estrie and Bas-Saint-Laurent regions (Quebec). Rams sera ( n = 258) were serologically evaluated from 224 rams in 30 commercial flocks and from 34 rams at 2 slaughterhouses by using an enzyme linked immunosorbent assay. Epididymides and testes were examined by palpation on farms and microscopically for culled rams. No ram was seropositive to Brucella ovis or had lesions suggestive of brucellosis from the farm or slaughterhouse surveys. 相似文献
7.
Extract Sir, —A recent issue of the Animal Health Division's excellent publication Surveillance (1978 No.5 Spring), reported that the Palmerston North Animal Health Laboratory had encountered a case involving 40 two-year-old rams, the majority of which had intramuscular perirenal abscesses. It was reported that these abscesses were due to vaccination with a single dose of Br. ovis vaccine, administered by the intraperitoneal route. 相似文献
8.
SUMMARY The epidemiology of ovine brucellosis was investigated in 6 ram flocks in which anomalous reactions to the complement fixation test was recorded. It was shown that rams can become infected as young as 4 months of age. Naturally infected animals have an epididymitis and excrete Brucella ovis in their semen or they may only show a serological response for a short time then recover. The base line titres of chronically infected animals stay relatively constant. The importance of abortive infection and possible reinfection is discussed. 相似文献
9.
Abstract AIM: To describe the pathology of the reproductive tract of red deer stags with active Brucella ovis infection and in stags in which B. ovis infection had resolved. METHODS: Twenty-three red deer stags of varying history were slaughtered and their epididymides and accessory sex glands examined grossly and by histopathology. At the time of slaughter five of the stags had an active B. ovis infection of 24–55 days duration following exposure to infected rams, 10 stags had been experimentally infected with B. ovis by intravenous inoculation 649 days previously and had developed an active infection but the bacterial infection had resolved at least 308 days prior to slaughter, and eight stags had not been exposed to B. ovis at any time. RESULTS: Of the five stags with an active infection, one had gross enlargement of the epididymides that could be detected by scrotal palpation. Histological lesions in all five stags included mild to severe, predominantly non-suppurative epididymitis, vesiculitis, prostatitis and ampullitis, with neutrophil exudation in associated glandular ducts. Additional lesions in the epididymides were spermatic granulomas and epithelial hyperplasia with intra-epithelial cyst formation. Of the 10 stags in which the bacterial infection had resolved, two had gross enlargement of the epididymides. The histological lesions were similar to those in stags with active infection but were generally milder, with increased periductal scar tissue in the epididymides. The lesions seen in stags resembled those seen in rams with B. ovis infection but they were usually less florid and had fewer plasma cells. No gross abnormalities or histopathological lesions were detected in the non-infected stags. CONCLUSIONS: Only a small percentage of red deer stags infected with B. ovis develop lesions of epididymitis that can be detected by scrotal palpation. Gross and histological lesions of the genital tract of stags associated with B. ovis infection are similar to the lesions seen in rams. Lesions in stags persist for >300 days after the bacterial infection has resolved. CLINICAL RELEVANCE: Brucella ovis infection should be considered when there are gross lesions of epididymitis or histological evidence of inflammation in the epididymides or accessory sex glands of red deer stags. Retrospective diagnosis of B. ovis in stags could be achieved by histological examination of the reproductive organs. 相似文献
10.
Summary A serological survey of 2160 Merino stud rams on 36 farms detected positive reactions greater than or equal to 1/100 in 42% of animals using the microscopic agglutination test (MAT) to Leptospira interrogans serovar hardjo. Twenty flocks had seroprevalence values greater than 30% with 15 flocks having values 60%. The enzymelinked immunosorbent assays showed that 47% and 3% of rams on the 36 farms were positive for IgG and IgM antibodies, respectively. Forty-five percent of hardjo reactions were in rams that had not been exposed to cattle. Significant correlations were found between IgM reactors and creek/dam water pumped into troughs, and between MAT/IgG reactors and total flock size. No statistical relationships were detected between positive reactors and two different annual average rainfall gradients, the time of the year in which samples were obtained, or agricultural regions of South Australia. Infections with an organism of the Sejroe serogroup is widespread in Merino stud rams. 相似文献
11.
Extract Sir:- I am concerned about the validity of the Complement Fixation Test (C.F.T.) for Brucella ovis in rams. 相似文献
12.
SUMMARY Palpable lesions within the scrotum but not associated with the testis or epididymis were detected in 20 of 200 merino rams in 3 flocks during routine veterinary examination. In 13 of 15 rams further examined Corynebacterium pseudotuberculosis was isolated from the lesions, which were typical CLA type abscesses. C. pseudotuberculosis was not shed in semen, and semen quality was normal in all affected rams. 相似文献
13.
A gel diffusion test with sonicated Brucella ovis antigen and an enzyme-linked immunosorbent assay based on heat-extracted antigen were used to distinguish false from true reactions in a complement fixation test based on heat-extracted antigen. Of 142 complement fixing reactors (occurring in supposedly Brucellu ovis-free, accredited flocks), the gel diffusion test correctly identified the status of 139 animals as compared to 128 with the enzyme-linked immunosorbent assay. A combination of the two methods resulted in a correct identification of 141 animals. The procedures provide an easy, cheap and quick way to determine the true status of reactors that show up during routine use of the complement fixation test in Brucella ovis re-accreditation procedures. 相似文献
14.
Extract S ince the introduction in 1957 of a vaccination procedure to control Brucella ovis infection in sheep, many thousands of rams have been vaccinated annually throughout New Zealand almost without complications. 相似文献
15.
Sarcoptes scabiei infestation was diagnosed in 278 sheep from 12 fatling flocks. The sheep presented crusted skin lesions initially appear
on the lips or nostrils, the lesion on nostrils also extend towards around the eyes, the supraorbital fossae and in some cases
over entire face. The infested male lambs by mating behavior in fatling flocks caused transmitting the infection to fat tail
area and scrutum. Histopathological study of lesions demonstrated marked acanthosis, hyperkeratosis, parakeratosis. Tunnels
could be observed in the hyperkeratotic stratum corneum and mite segments were located mainly in the stratum corneum and also
in the stratum granulosum. Attempts to eliminate S. scabiei var. ovis were made in 3 naturally infested sheep herds, by two dippings with two weeks interval with Amitraz, Cypermetrin and Prompetamphos.
The results of this study indicate that acaricidal treatment of S. scabiei var. ovis in 3 naturally infested herds was successful, but a few cases of reinfestation were found in each treated group. 相似文献
16.
Mycoplasma ovis (formerly Eperythrozoon ovis) is an epierythrocytic parasitic bacterium of small ruminants known as haemotropic mycoplasma, which is transmitted mechanically by biting flies and contaminated instruments. Acute mycoplasmosis causes severe haemolytic anaemia and mortality in young animals. At the same time, chronic disease may produce mild anaemia and varying degrees of morbidity depending on several factors, including age, reproductive status, the plane of nutrition, immunological status and the presence of concurrent infection. Haemotropic Mycoplasma ovis is currently recognised as an emerging zoonotic pathogen which is widely distributed in the sheep and goat producing areas of tropics and subtropics, where the disease is nearly endemic. Human infection has been reported in pregnant women, immunocompromised patients and people exposed to animals and arthropods. The current diagnosis of haemoplasma relies on microscopic evaluation of Giemsa-stained blood smear and PCR. Although there are few published reports on the incidence of haemotropic Mycoplasma ovis infection of small ruminants in Malaysia, information on its prevalence, risk factors, severity and economic impacts is grossly inadequate. Therefore, a large-scale survey of small ruminant flocks is necessary to elucidate the current seroprevalence status and molecular characteristics of haemotropic M. ovis infection in Malaysia using ELISA and PCR sequencing technologies. In the future, surveillance programs, including vector forecast, quarantine, monitoring by periodic surveys and public enlightenment, will limit the internal and transboundary spread of M. ovis, enhance control efforts and mitigate production losses in Malaysia. 相似文献
17.
The aim of this study was to clarify the causes of scrotal enlargement in rams and bucks in Qassim region of Saudi Arabia. Enlarged scrotal contents of rams and bucks (n = 153) were examined by visual inspection, palpation, and ultrasonography. Blood samples were obtained and tested for Brucella sp. infection. Clinical and ultrasonographic findings showed that scrotal enlargement was mainly associated with orchitis, peri-orchitis, and epididymitis. Miscellaneous findings were scrotal hernia, scrotal hematoma, and hydrocele. The frequencies of orchitis, peri-orchitis, and epididymitis were 47.4, 21.1, and 14.1% in Awassi rams; 54.5, 21.7, and 8.7% in Najdi rams; 52.3, 20.5, and 9.1% in Ardi bucks; and 50, 16.7, and 16.7% in Damascus bucks, respectively. Orchitis was associated with no-abscess formation (23%), single-abscess formation (15.4%), and multiple-abscesses formation (61.6%). Peri-orchitis was characterized by hard consistency, atrophy of the testes, and extensive connective tissue formation. Epididymitis was observed mainly at the tail of the epididymis (82.4%) but rarely at the head (17.6%). Epididymitis was associated in many cases with abscessation (70.6%). Males with orchitis, peri-orchitis, and epididymitis were positive for Brucella melitensis and Brucella ovis in the frequency of 21.3% and 48.8%, respectively. In conclusion, scrotal enlargement in rams and bucks in Qassim region is caused mainly by inflammation of the testis and/or epididymis and associated tremendously with brucellosis seropositivity. 相似文献
18.
Breeding circles allow genetic management in closed populations without pedigrees. In a breeding circle, breeding is split over sub‐populations. Each sub‐population receives breeding males from a single sub‐population and supplies breeding males to one other sub‐population. Donor‐recipient combinations of sub‐populations remain the same over time. Here, we derive inbreeding levels both mathematically and by computer simulation and compare them to actual inbreeding rates derived from DNA information in a real sheep population. In Veluws Heideschaap, a breeding circle has been in operation for over 30 years. Mathematically, starting with inbreeding levels and kinships set to zero, inbreeding rates per generation (Δ F) initially were 0.29%–0.47% within flocks but later converged to 0.18% in all flocks. When, more realistically, inbreeding levels at the start were high and kinship between flocks low, inbreeding levels immediately dropped to the kinship levels between flocks and rates more gradually converged to 0.18%. In computer simulations with overlapping generations, inbreeding levels and rates followed the same pattern, but converged to a lower Δ F of 0.12%. Δ F was determined in the real population with a 12 K SNP chip in recent generations. Δ F in the real population was 0.29%, based on markers to 0.41% per generation based on heterozygosity levels. This is two to three times the theoretically derived values. These increased rates in the real population are probably due to selection and/or the presence of dominant rams siring a disproportionate number of offspring. When these were simulated, Δ F agreed better: 0.35% for selection, 0.38% for dominant rams and 0.67% for both together. The realized inbreeding rates are a warning that in a real population inbreeding rates in a breeding circle can be higher than theoretically expected due to selection and dominant rams. Without a breeding circle, however, inbreeding rates would have been even higher. 相似文献
19.
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
20.
SUMMARY The scrotal contents of 2,281 Merino rams of wide age range examined at 3 abattoirs in Perth, Western Australia, showed a 40% prevalence of rams with 1 or more gross lesions. The percentage prevalence of gross lesions found on autopsy were: adhesions 21, testicular atrophy/hypoplasia 14, testicular calcification 13, congenital cyst of the epididymis 6, cryptorchidism 4, chronic epididymitis/scrotal abscesses 2, varicocoele 2, testicular aplasia1, seminoma1. The prevalence of lesions increased with age of rams. Testicular atrophy was often present when varicocoele, chronic epididymitis and scrotal abscess affected that side of the scrotal sac. Corynebacterium spp was the most frequent isolate from chronic epididymitis. Actinobacillus seminis was isolated once and Brucella ovis was not isolated. About 20% of the rams showed lesions compatible with a diagnosis of reproductive unsoundness. A large proportion of lesions were revealed only after removal of the scrotum and most of these did not appear to affect normal spermatogenesis except for an estimated 9% of rams, which showed mild atrophy/hypoplasia. Samples of these testes showed mild to moderate changes in spermatogenesis on histopathology. It was postulated that the latter group of rams might represent those ill-defined clinical cases which show equivocal results on appraisal of semen samples despite the presence of palpably normal testes. 相似文献
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