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1.
AIM: To determine the aetiology of a recurring and severe form of infectious keratoconjunctivitis (IKC) in sheep. METHODS: Five sheep flocks that had experienced a severe form of IKC were examined. Clinical history, conjunctival swabs and blood samples were collected from affected animals. Culture for bacteria, and also specifically for Mycoplasma and Chlamydophila spp, and detection of Mycoplasma conjunctivae DNA by polymerase chain reaction (PCR) were attempted. Serum samples were tested for antibodies to M. agalactiae, M. capricolum, M. conjunctivae and Chlamydophila spp. RESULTS: Mycoplasma conjunctivae DNA was detected using PCR in 3/5 flocks, and in all flocks antibodies to M. conjunctivae were detected in sera. A pure growth of Branhamella ovis was cultured from conjunctival swabs from a small proportion of sheep in two flocks. No other pathogens were detected. CONCLUSIONS: This investigation demonstrated that M. conjunctivae was a primary pathogen causing severe IKC in sheep, and is the first report of detection of this organism in sheep in New Zealand. Introduction of clinically normal carrier sheep appeared to have caused the outbreaks. KEYWORDS: Infectious keratoconjunctivitis, Mycoplasma conjunctivae, Chlamydophila pecorum, Branhamella ovis, polymerase chain reaction, ELISA, complement fixation test.  相似文献   

2.
Summary

Five sheep, free from Mycoplasma conjunctivae and ocular Chlamydia infection, were experimentally inoculated with M. conjunctivae and five more sheep were exposed to the infection by contact. Keratoconjunctivitis developed in all ten sheep. As in natural outbreaks of infectious keratoconjunctivitis (IKC), clinical signs were generally moderate and transient, and recurred in some sheep. M. conjunctivae was detected throughout the 53‐day observation period. Clinical diagnosis was confirmed by histopathologic examination of three sheep. Moraxella ovis, found in six of the ten sheep before the start of the experiment, appeared to play no etiologic role in the development of IKC.  相似文献   

3.
Mycoplasma conjunctivae are etiological agents of infectious keratoconjunctivitis (IKC), commonly known as pink-eye in domestic sheep, goats and other wild animals in many parts of the world. A few young Lohi lambs maintained at Livestock Experiment Station (LES), Bahadurnagar, Okara, Pakistan showed clinical signs and symptoms of conjunctivitis, keratitis, severe lacrimation and varying degree of blindness. During January to March, 2011, a total of 36 ocular swabs were collected from IKC affected animals and were processed for isolation, identification, and characterization of M. conjunctivae. Sixteen (44.44 %) out of 36 samples showed turbidity in PPLO broth. Twelve (75 %) out of 16 broth samples showed colony growth on PPLO agar. All 16 (44.44 %) out of 36 turbid broth samples, 12 (75 %) out of 16 cultured on agar plate samples, and 21 (59 %) out of 36 sheep ocular direct swab samples were found positive for M. conjunctivae through polymerase chain reaction test by using M. conjunctivae-specific primer pair McoF1 and McoR1 and detecting a 750 base pair fragment on agarose gel. Topical application of 0.5 % sterile solution of gentamycin (100 mg/ml) (Gentafar 10 %, FARVET, Netherlands) proved suitable for the treatment of IKC in Lohi lambs as all clinical signs of IKC disappeared after 5 days of treatment with this antibiotic. This is the first report about the prevalence, molecular diagnosis, and treatment of M. conjunctivae in Lohi sheep affected with infectious keratoconjunctivitis at LES, Bahadurnagar, Okara, Pakistan.  相似文献   

4.
A specific PCR assay based on unique sequences of the rrs genes (16S rRNA) of Mycoplasma conjunctivae was developed for direct detection and identification of this pathogen from clinical material. DNA from eye swabs was amplified after a simple lysis step by either a single PCR with the M. conjunctivae specific primer pair McoR1 and McoF1, or by a nested PCR with the Mycoplasma genus specific primer pair MOLIGEN1-L and 16UNI-R in the first step and McoR1 and McoF1 in the second step. The specificity of the primer pair McoR1 and McoF1 was verified with purified DNA from the type strain, from 17 field isolates of M. conjunctivae and from several Mollicutes which are phylogenetically related to M. conjunctivae or which can be isolated from the same host animals. This method identified mycoplasma isolates from goat, sheep, ibex and chamois originating from different countries as M. conjunctivae. No cross amplifications with other mycoplasmas which are related to M. conjunctivae were observed. Eye swab samples containing known numbers of M. conjunctivae cells were analysed after direct lysis of the material. The detection level was estimated to be 20 cells per swab when the nested PCR procedure was used and 2 × 105 by the single PCR method. In an experimental infection model of sheep, the nested PCR method for detection of M. conjunctivae gave results which were comparable to mycoplasmal culture. These are the implications for diagnostic purposes: M. conjunctivae isolates can be identified by the one-step PCR method, whereas for detection and identification of M. conjunctivae in clinical material the two-step method should be used (higher sensitivity).  相似文献   

5.
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6.
ABSTRACT

Aims: To compare detection by real-time PCR of DNA from Mycoplasma bovis on mucosal swabs taken from the palatine tonsillar crypt and the mainstem bronchi of clinically asymptomatic calves after slaughter.

Methods: We compared the sensitivity of mucosal swabs taken from two sites: the palatine tonsillar crypt and the mainstem bronchi. Paired samples were taken post-mortem at slaughter from 55 clinically well calves from an infected herd and were tested by real-time PCR for the presence of M. bovis-specific DNA.

Results: Mycoplasma bovis DNA was detected in 51 palatine tonsillar crypt swabs (92.7 (95% CI?=?82.4–98.0)%) and seven mainstem bronchial swabs (12.7 (95% CI?=?5.3–24.5)%). All seven calves with positive mainstem bronchial swabs also had positive palatine tonsillar crypt swabs.

Conclusions: When compared to mucosal swabs of the mainstem bronchi, mucosal swabs of the palatine tonsillar crypt were seven times more sensitive for the post-mortem detection of M. bovis DNA. The viability of detected M. bovis was not assessed, because any cattle carrying viable or non-viable M. bovis DNA were determined to be a potential risk to eradication. Palatine tonsillar crypt mucosa may be a useful anatomical site for real-time PCR detection of M. bovis DNA in naturally infected calves. More work is needed to define the persistence and viability of M. bovis at this anatomical site.

Clinical relevance: The results of this study helped form the basis of surveillance tools used in M. bovis control and eradication efforts. Familiarity with these results may help veterinarians better communicate with their clients about the science behind the eradication efforts.  相似文献   

7.
《Veterinary microbiology》1998,61(4):279-288
We evaluated the susceptibility of alpine ibex (Capra ibex ibex) to mycoplasmal conjunctivitis induced by a strain of Mycoplasma conjunctivae isolated from domestic sheep by inoculation of three alpine ibexes with 1.2×106 colony forming units of M. conjunctivae in the conjunctival sac of both eyes. One more ibex was exposed to the infection by contact. Experimental animals were free of M. conjunctivae and ocular Chlamydia infection before inoculation. Conjunctivitis and serous to mucous lachrymation became apparent in all four ibexes. Clinical signs began within 2 days in inoculated animals and 22 days after the beginning of the experiment in the contact ibex. M. conjunctivae was demonstrated up to the 63th day post-inoculation by cultural and PCR-methods. After 63 days, histopathologic examination revealed nearly normal ocular tissues, and M. conjunctivae could be detected from two eyes only. No other infectious agents which might cause conjunctivitis or keratitis, including Chlamydia psittaci and Branhamella ovis, were involved. Our investigation indicates that sheep-strains of M. conjunctivae can induce conjunctivitis in alpine ibex, thus showing pathogenicity of this organism for Caprinae species other than domestic sheep and goats.  相似文献   

8.
After several thousand sheep had been imported from Australia and New Zealand to Croatia during 1995, many native sheep that had been in contact with the imported animals acquired a severe ocular disease closely resembling infectious keratoconjunctivitis. In affected flocks glucose-fermenting mycoplasma were isolated from 48 per cent of conjunctival swabs and Branhamella ovis from 58 per cent. Twelve of 42 culturally and biochemically identical isolates were identified as Mycoplasma conjunctivae by polymerase chain reaction. From the conjunctivae of two animals M conjunctivae and M arginini were isolated in mixed culture. For many reasons most farmers removed the imported animals from their flocks and only sporadic cases of the disease were recognised in 1996. At the end of 1997, six flocks which were clinically free of the disease but had been affected during 1995, and five flocks with no history of the severe ocular disease were examined clinically and microbiologically, and were found to be free of M conjunctivae infection. At the time, B ovis was cultured almost exclusively from sheep originating from flocks which had been affected during 1995 and/or 1996. It was usually isolated in pure culture or as the predominant bacterial species, and was often accompanied by mild conjunctivitis. There were no microbiologically confirmed new cases of infectious keratoconjunctivitis during 1998 and 1999.  相似文献   

9.
Infectious Ovine Keratoconjunctivitis (IOK) is a contagious ocular disease of sheep. A range of organisms have been observed as the aetiological agents of IOK. In this study, the presence of chlamydial pathogens (C. pecorum, C. abortus, C. psittaci) in conjunctival swabs was tested for. The swabs were collected from sheep with varying grades of IOK in an Australian pre‐export feedlot. The sheep had been rejected from a shipment because of the eye disease. The relative contribution of chlamydial pathogens to IOK and the rejection of animals was evaluated. In total, 149 conjunctival swabs were taken from rejected sheep (IOK Grades 1 to 6; n = 126) as well as those with healthy eyes (Grade 0; n = 23). Screening for chlamydial pathogens was done using species–specific qPCR assays. Chlamydial DNA was detected in 35.6% (53/149) of conjunctival samples. C. pecorum was the most predominant species with an overall prevalence of 28.9% (43/149). C. psittaci prevalence was 6.7% (10/149). Both organisms were detected in healthy as well as IOK‐affected eyes. All swabs tested negative for C. abortus. The results from this study demonstrate that Chlamydia spp can be readily detected in sheep presenting with IOK. The zoonotic C. abortus was not detected in any of the samples in this study, providing further evidence to the suggestion that this pathogen remains absent from Australia. Although the exact contribution of Chlamydia spp in the IOK pathogenesis is unclear, such studies are anticipated to be of benefit to Australian domestic and live export production systems.  相似文献   

10.
AIM: To develop a real-time PCR for the detection of Mycoplasma agalactiae, using PCR primers targeting the ma-mp81 gene.

METHODS: A group of 15 M. agalactiae isolates, 21 other Mycoplasma spp. isolates and 21 other bacterial isolates was used in evaluation of the assay.

RESULTS: All M. agalactiae isolates were detected by the assay and none of the non-target isolates was amplified. The analytical detection limit of the assay was 10 fg of purified genomic DNA and 104 cfu/ml milk inoculated with M. agalactiae. When applied to goat-milk samples collected from three herds free of M. agalactiae infection, the assay had a specificity of 100%.

CONCLUSIONS: The assay would be useful in a diagnostic laboratory, providing specific, sensitive and rapid detection of M. agalactiae.  相似文献   

11.
Abstract

AIMS: To obtain information and compare the prevalence of Chlamydiaceae in riverine buffalo (Bubalus bubalis) and cows (Bos taurus) in Egypt with and without clinical signs of reproductive disease.

METHODS: Vaginal swabs and blood samples were collected from animals attending Governmental Veterinary Clinics without (buffalo n=39, cows n=20) and with (buffalo n=63, cows n=53) signs of reproductive disease. Serum samples were tested for antibodies to Chlamydiaceae using complement fixation testing (CFT). Vaginal swabs were tested for Chlamydiaceae following inoculation into Vero cells and 6-day-old embryonated chicken eggs, using modified Giménez and immunoperoxidase staining, PCR analyses targeting the omp2 gene, and Restriction Fragment Length Polymorphism PCR (RFLP-PCR) for species identification.

RESULTS: Antibodies to Chlamydiaceae were detected in 30/39 (77%) and 50/63 (79%) buffalo without and with signs of reproductive disease, respectively, and 10/20 (50%) and 39/53 (74%) of cows with and without signs of reproductive disease, respectively. Positive samples from PCR analysis were identified in 31/39 (79%) and 37/63 (59%) buffalo without and with signs of reproductive disease, respectively, and 12/20 (60%) and 46/53 (89%) of cows without and with signs of reproductive disease, respectively. Using RFLP-PCR, 57/68 (84%) of samples from buffalo, and 47/58 (81%) from cows, were identified as Chlamydophila psittaci and the reminder as Cp. abortus. From the CFT and PCR results there was no significant difference in the prevalence of positive samples between species, or between animals without or with signs of reproductive disease.

CONCLUSION: The presence of anti-Chlamydiaceae antibodies in 77% of the animals with signs of reproductive disease and the detection of Chlamydiaceae in 72% of vaginal swabs of the animals suggest a pathogenic role by Chlamydiaceae in riverine buffalo and cows. The main Chlamydiaceae found in the genital tract of cattle in Egypt were Cp. psittaci and Cp. abortus.

CLINICAL RELEVANCE: Chlamydophila spp. should be included in diagnostic algorithms for reproductive disorders, in order to assess the real burden of Chlamydophila associated disease in buffalo and cattle and to evaluate the potential value of vaccines.  相似文献   

12.
Bacteriological and serological investigations were performed to assess whether the domestic sheep population is a reservoir of Mycoplasma conjunctivae in Switzerland. Among a sample of 69 sheep showing clinical signs of infectious keratoconjunctivitis (IKC) in three Swiss cantons, M. conjunctivae was identified 53 times (76.8%). A commercially prepared indirect ELISA was used to detect M. conjunctivae antibodies in 674 sera of adult sheep. We analysed a stratified random sample of 123 sheep herds from 25 out of the 26 Swiss cantons. At least one positive animal was detected in 89.4% of the herds. In positive herds (n=110), 57.1% of the individual animals tested positive. To assess the importance of sheep's age in the spread of M. conjunctivae, 209 sera of adult sheep and 93 lamb sera among eight sheep herds were analysed using the indirect ELISA. Seroprevalence in 2-6-month-old lambs was 50.5%, indicating that the IKC agent is spread in sheep flocks during raising. Lambs experimentally infected with M. conjunctivae carried the agent for 8 and 23 weeks, respectively, depending on the strain used for challenge. We conclude that the M. conjunctivae-infection is endemic and self-maintained in the domestic sheep population in Switzerland.  相似文献   

13.
Five sheep, free from Mycoplasma conjunctivae and ocular Chlamydia infection, were experimentally inoculated with M. conjunctivae and five more sheep were exposed to the infection by contact. Keratoconjunctivitis developed in all ten sheep. As in natural outbreaks of infectious keratoconjunctivitis (IKC), clinical signs were generally moderate and transient, and recurred in some sheep. M. conjunctivae was detected throughout the 53-day observation period. Clinical diagnosis was confirmed by histopathologic examination of three sheep. Moraxella ovis, found in six of the ten sheep before the start of the experiment, appeared to play no etiologic role in the development of IKC.  相似文献   

14.
Objective To investigate how different sampling techniques affect detection of DNA from feline herpes virus Type 1 (FHV-1), Chlamydophila felis and Mycoplasma felis and to study the correlation between positive test results and clinical signs in cats. Animals Fifty-one cats; 24 with ocular signs and 27 healthy control cats. Procedures Samples were collected from all cats using cotton swabs, conjunctival and corneal biopsies, and corneal scrapings. Samples were analyzed for presence of FHV-1, C. felis, M. felis, and feline DNA, defined by 28S rDNA, by using real-time PCR. Results In affected cats, FHV-1 was detected in only one cat; C. felis and M. felis were not detected in any affected cats. None of the three organisms was detected in any control cats. Feline DNA was demonstrated in all conjunctival samples, in 82% of corneal swabs, 92% of corneal scrapings, and 100% of keratectomy samples. Conclusions Because of the generally low detection rate for FHV-1, C. felis, and M. felis DNA in this study, differences regarding sampling technique could not be determined and correlation between positive test results and degree of clinical signs could not be made. Detection of feline DNA in most samples irrespective of sampling technique, suggests a low prevalence of FHV-1, C. felis and M. felis in this population of cats.  相似文献   

15.

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   

16.
The serological cross reactions between Mycoplasma conjunctivae, the etiological agent of infectious keratoconjunctivitis (IKC), and the antigenetically and phylogenetically closely related Mycoplasma ovipneumoniae, which is often found in sheep, were analysed. Cross reacting antigens were identified using sera from sheep with IKC and from sheep of herds known to be free of IKC, as well as rabbit hyperimmune serum specific to the two Mycoplasma species. Cross reactions were predominantly due to the strongly antigenic proteins of 42 kDa and 83 kDa. Serospecific antigens of M. conjunctivae could be separated from cross-reacting antigens by the extraction of Tween 20-soluble membrane proteins. The Tween 20-extracted proteins of the M. conjunctivae strain HRC/581T were used for the development of an indirect ELISA test. This ELISA test was shown to be a useful serological method for the diagnosis of M. conjunctivae infections and to identify infected sheep herds.  相似文献   

17.
Mycoplasma conjunctivae is considered the major cause of infectious keratoconjunctivitis (IKC) in Alpine ibex (Capra i. ibex) and chamois (Rupicapra r. rupicapra). While it is known that domestic sheep can act as healthy carriers for M. conjunctivae, this question has not been addressed in wild ungulates so far. In this study, bacteriological investigations and field observations were performed to assess whether free-ranging Alpine ibex can be healthy carriers of M. conjunctivae. Among 136 ibex without clinical signs of IKC, M. conjunctivae was identified 26 times (19.1%) by TaqMan PCR. To assess the potential pathogenicity of M. conjunctivae strains isolated from asymptomatic eyes, strains from three healthy ibex and from 15 IKC-ibex and IKC-chamois were analysed genetically by DNA sequence analysis of the variable part of the lppS gene. No significant differences were observed between strains from asymptomatic and clinically affected animals, reflecting the assumption that healthy ibex may act as carriers for M. conjunctivae strains that may be pathogenic for other individuals. Our results further indicate that development of IKC is associated with M. conjunctivae load in the eyes. In addition, a questionnaire survey revealed that IKC is generally less common in ibex than chamois and that infection in wild ungulates is not necessarily linked to the presence of sheep. These data support the hypothesis that apparently healthy ibex may be important in the epizootiology of IKC and indicate that host predilection may play a role in IKC development.  相似文献   

18.
Abstract: An injured juvenile red‐tailed hawk (Buteo jamaicensis) was evaluated at the Veterinary Medical Teaching Hospital at the University of California, Davis. The hawk was quiet, alert, and emaciated, and had a closed comminuted, mid‐diaphyseal ulnar fracture. CBC results included heterophilia with a left shift, monocytosis, and increased plasma fibrinogen concentration. The blood smear included rare heterophils containing small, dark blue inclusions approximately 1–2 μm in diameter that ranged from round to coccobacillary in shape and formed variably shaped aggregates; the morphology of the inclusions was suspicious for Chlamydophila or Ehrlichia spp. pathogens. The hawk died, and histopathologic examination of tissues obtained at necropsy found severe multifocal histiocytic and heterophilic splenitis in addition to chronic hepatitis, myocarditis and epicarditis, meningoencephalitis, and airsacculitis. Using immunohistochemistry the presence of Chlamydia/Chlamydophila spp. antigen within multiple tissues was confirmed. Chlamydophila psittaci DNA was demonstrated in whole blood and fresh splenic tissue via real‐time PCR. Direct fluorescent antibody staining of air‐dried blood smears was positive in rare leukocytes for Chlamydia/Chlamydophila spp. antigen, and immunocytochemical staining of blood smears for Chlamydia/Chlamydophila spp. antigen was focally positive in rare heterophils. These findings may represent the first reported diagnosis of natural avian C. psittaci infection by visualization of organisms in peripheral blood heterophils. Immunocytochemical evaluation of blood smears was valuable in confirming the diagnosis and may be a useful antemortem test to discriminate between bacteria and other inclusions within heterophils.  相似文献   

19.
During the period from January 2002 to December 2003, serum samples were collected from 104 small ruminant flocks consisting of 18 sheep flocks, 27 goat flocks, and 59 mixed flocks containing both sheep and goats in northern Jordan. Only female sheep and goats were sampled. At least five females aged over 2 years per flock per species were sampled and examined for Mycoplasma mycoides subspecies capri using the latex agglutination test. To increase the chances of detecting positive flocks, sick or older ewes were sampled. Specific information was obtained using a questionnaire to identify potential risk factors for M. mycoides subsp. capri seropositivity in small ruminants. The true flock-level seroprevalences of M. mycoides subsp. capri were 34%, 32%, and 38% in small ruminants (sheep and goats), sheep, and goats, respectively. Differences between flock-level seroprevalences in sheep and goats were not significant (p = 0.7). Multivariable logistic regression analysis of 21 production and health management practices showed four to be associated with M. mycoides subsp. capri seropositivity including flocks which were grazed and fed concentrate supplement (OR = 4.6), improper cleaning of milking utensils (OR = 4.7), buying new animals to replace culled ones (OR = 0.3), and treating against helminths when clinical signs of helminth infections appear (OR = 0.4).  相似文献   

20.
Mycoplasma bovoculi and Mycoplasma bovis were both isolated from conjunctival swabs taken from young calves showing symptoms consistent with infectious bovine keratoconjunctivitis (pinkeye). No Moraxella spp. or other nonmycoplasma bacteria were isolated in association with this severe clinical outbreak. Based on laboratory tests and clinical observations, the first phase of the disease was likely pneumonic in nature, possibly caused by bovine respiratory syncytial virus and M. bovis. In the subsequent phase of the disease course, infection with both M. bovoculi and M. bovis resulted in ocular disease. A combination of microbiological, serological, and molecular diagnosticmethods was used to elucidate the etiology of the outbreak.  相似文献   

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