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1.
Anaplasma and Ehrlichia are important emerging tick‐borne pathogens in both humans and animals. Here, we conducted a molecular surveillance study in Gansu, China to assess the prevalence of Anaplasma and Ehrlichia spp. in red deer and sika deer based on polymerase chain reaction (PCR) analysis and sequencing of 16S rRNA or msp genes. PCR revealed that the prevalence of Anaplasma ovisAnaplasma bovis and Anaplasma platys of the Qilian Mountain samples was 32%, 9% and 9%, respectively; the prevalence of Anaplasma ovis, Anaplasma bovis, Anaplasma platys was 20%, 15% and 15% among the Long Mountain samples, respectively. Of the Long Mountain samples, two (5%) of the 40 samples were positive for Ehrlichia canis, but all 44 of the Qilian Mountain samples were negative for E. canis, and no other Anaplasma or Ehrlichia spp. were found in the samples. The phylogenetic tree showed that the newly isolated Anaplasma and Ehrlichia spp. could be classified as belonging to four clades, including an A. bovis cluster, A. ovis cluster, A. platys cluster and E. canis cluster. In addition, Bartonella schoenbuchensis was firstly identified in blood samples from red deer in Gansu, China. Our results provide important data to increase the understanding of the epidemiology of anaplasmosis and ehrlichiosis of red deer and sika deer and will assist with the implementation of measures to control anaplasmosis and ehrlichiosis transmission to red deer, sika deer and other animals in Gansu, China.  相似文献   

2.
Mycobacterium bovis, the causative agent of tuberculosis in animals, has a broad host range, including humans. Historically, public health concerns prompted programs to eradicate tuberculosis from cattle in many nations. Eradication efforts decreased the prevalence of bovine tuberculosis; nevertheless, some countries encountered significant obstacles, not least of which was a wildlife reservoir of M. bovis. Efforts to decrease the size of the affected wildlife populations have neither eliminated disease nor eliminated transmission to cattle. Consequently, the use of a vaccine for wildlife is being explored. The vaccine most studied is M. bovis BCG, an attenuated live vaccine, first developed 100 years ago. The most efficient and effective means of vaccinating wildlife will be an oral vaccine. White‐tailed deer in Michigan, USA, constitute a reservoir of M. bovis. White‐tailed deer are a popular game species, and as such, represent a food animal to many hunters. BCG persistence in deer tissues could result in human exposure to BCG. Although non‐pathogenic, BCG exposure could induce false‐positive skin test results, confounding the central component of public health surveillance for TB. The objective of the present study in white‐tailed deer was to evaluate persistence of lipid‐encapsulated BCG and a liquid suspension of BCG after oral administration at two different dosages. Vaccine was not recovered at any time after oral consumption of a bait containing a single dose (1 × 108 CFU) of lipid‐encapsulated BCG. However, persistence was consistent in deer consuming 10 lipid‐encapsulated baits (1 × 109 CFU), with BCG recovered from at least one deer at 1, 3, 6, 9 and 12 months after consumption. Persistence of up to 9 months was seen in deer vaccinated with orally with a liquid suspension. Persistence of BCG was limited to lymphoid tissue and never found in samples of muscle collected at each time point. Although the risk of exposure to hunters is low, BCG persistence should be considered prior to field use in white‐tailed deer.  相似文献   

3.
Recently, an increasing number of Bartonella species have been emerged to cause human diseases. Among animal reservoirs for Bartonella spp., bats stand out due to their high mobility, wide distribution, social behaviour and long‐life span. Although studies on the role of vampire bats in the epidemiology of rabies have been extensively investigated in Latin America, information on the circulation and genetic diversity of Bartonella species in these bat species is scarce. In the present work, 208 vampire bats, namely Desmodus rotundus (the common vampire bat; n = 167), Diphylla ecaudata (the hairy‐legged vampire bat; n = 32) and Diaemus youngii (the white‐winged vampire bat; n = 9) from 15 different states in Brazil were sampled. DNA was extracted from liver tissue samples and submitted to real‐time PCR (qPCR) and conventional PCR (cPCR) assays for Bartonella spp. targeting five genetic loci, followed by phylogenetic and genotype network analyses. Fifty‐one out of 208 liver samples (24.51%) were positive for Bartonella DNA in the ITS real‐time PCR assay [40 (78.43%) of them were from D. rotundus from 11 states, and 11 (21.57%) samples from D. ecaudata from three states. Eleven genotypes were found for each gltA and rpoB genes. Several ITS sequences detected in the present study clustered within the lineage that includes B. bacilliformis and B. ancachensis. The Bayesian phylogenetic inference based on the gltA gene positioned the obtained sequences in six different clades, closely related to Bartonella genotypes previously detected in D. rotundus and associated ectoparasites sampled in Latin America. On the other hand, the Bartonella rpoB genotypes clustered together with the ruminant species, B. schoenbuchensis and B. chomelii. The present study describes for the first time the molecular detection of Bartonella spp. in D. ecaudata bats. It also indicates that Bartonella spp. of vampire bats are genetically diverse and geographically widespread in Brazil.  相似文献   

4.
In this work, an experimental model for chronic besnoitiosis in bovine was developed and characterized. Using a previously established calf model, two new variables (parasite stage and inoculation route) were combined and used. Twelve Holstein Friesian 3‐month‐old male calves were randomly divided into four groups of three animals each. Bradyzoites were obtained from a chronically infected bull and used for inoculation via three different inoculation routes. Three groups were inoculated with 106 bradyzoites by intravenous (G1), subcutaneous (G2) and intradermal (G3) routes, and a non‐infected control group (G4) was inoculated with PBS. The trial lasted for 90 days and included daily clinical monitoring as well as weekly skin biopsies and blood sampling. Sera were obtained to analyse both cellular and humoral responses. Once the calves were euthanized, tissues from the skin, eyes, respiratory and reproductive tracts, among others, were collected to study presence of the parasite. Clinically, the infection was classified as mild to moderate for the acute stage since all infected calves showed lymphadenopathy from four days post‐infection (pi) and fever from one week pi until 24 days pi. However, the most relevant results were achieved during the chronic stage that was classified as moderate to severe. In fact, pathognomonic conjunctival cysts were observed in all infected calves from 40 days pi onwards and were more abundant in G3. Moreover, one calf from this group developed skin lesions (49 days pi). The microscopic tissue cysts and Besnoitia DNA were detected primarily in skin, reproductive tract and respiratory tissue samples, and parasite load was higher in G3. In conclusion, the parasite stage (bradyzoite) and the inoculation route are key factors that influence the outcome of an infection. In particular, the intradermal route led to more severe clinical signs of the chronic phase in the inoculated calves.  相似文献   

5.
The recent spread of bovine besnoitiosis warrants further epidemiological investigations to improve the knowledge on disease development. Thus, a 4‐year longitudinal open cohort study was conducted in the first German cattle herd naturally infected with Besnoitia besnoiti . At seven herd‐visits between 2008 and 2012, fourteen breeding bulls (>1.5 years) and 131 females (>1 year) were examined clinically and serologically. In females, clinical and serological prevalences, incidence and remission rates were determined. In addition, the association of age, antibody levels and number of visible parasitic cysts with clinical and serological outcome was investigated. The seroprevalence (89.4%–100%) and serological incidence rate (140.5 per 100 animal‐years) were considerably higher than the clinical prevalence (23.5%–36.6%) and clinical incidence rate (16.7 per 100 animal‐years). Of 33 new clinical and 12 new serological cases, only 6.7% (3/45) attracted attention with clinical signs of acute bovine besnoitiosis. The apparent serological remission rate (1.9 per 100 animal‐years) was considerably lower than the clinical remission rate (37.3 per 100 animal‐years). A median cyst score of <1 and mean immunofluorescent antibody test (IFAT ) titre of ≤1,600 over the entire observation period was significantly associated with a negative clinical outcome at the end. Overall cyst score was not significantly associated with serological outcome and age had no significant influence on clinical and serological outcome. Within 4 years, there was a significant reduction in cyst scores and IFAT titres in the same animals, leading to eight clinically and serologically negative animals in the end. Two initially negative animals achieved clinical and apparent serological remission in about 2.5 years. In bulls, the time between herd entry and seroconversion was 7–30 months and the serological incidence rate was nearly identical to the rate in females (142.0 per 100 animal‐years). This shows that a high B. besnoiti prevalence leads to infection of bulls within a short time period.  相似文献   

6.
Giardia duodenalis is a common intestinal parasite in humans and a wide range of livestock species. It is a genetically heterogeneous parasite that has been characterized in seven distinct genetic assemblages or cryptic species, and molecular markers can be used to differentiate both animal‐specific and potentially zoonotic genotypes. Little is known about G. duodenalis and the range of assemblages occurring in domestic livestock species in the UK. Here, we present data on the occurrence and molecular diversity of G. duodenalis detected in the faeces or large intestinal contents of cattle, sheep, pigs, goats and camelids from farms in the north‐west of England. Both healthy and clinically diseased animals were included in the survey. The presence of Giardia spp. and assemblages was determined by sequencing of the small‐subunit ribosomal RNA gene. The potential association of infection with various clinical and epidemiological parameters was studied in cattle using both univariate and multivariate analyses. Giardia spp. were detected in 127 (34.3%) of the 370 animals tested. G. duodenalis assemblage E was found to be predominant in cattle and sheep, followed by assemblage A. Mixed infections with assemblages A and E were also detected. Interestingly, some cattle, sheep and pigs were found to be infected with more unexpected assemblages (C, D, F). Pre‐weaned calves were more likely to test positive than adult animals, but no association between the occurrence of overt intestinal disease and G. duodenalis infection was detected. The common occurrence of assemblage A and the finding of unusual assemblages in atypical hosts suggest that in future, a multilocus analysis should be used to confirm the actual diversity of G. duodenalis in livestock and the presence of potentially zoonotic genotypes. These data also suggest that there is a need to re‐evaluate the clinical significance of G. duodenalis infection in livestock.  相似文献   

7.
Porcine circovirus 3 (PCV‐3) has emerged as a potential threat for swine industry, being consistently reported in the presence of several clinical signs all around the world. Recently, its presence in wild boar has been demonstrated at high prevalence. This evidence is surprising since the lower density of wild populations might not be expected to sustain such efficient viral transmission. Porcine circoviruses were proven to exhibit a certain plasticity in the host tropism and were detected in unrelated species, like mice, dogs and ruminants. However, if this scenario applies also to wild animals remains to be established. Therefore, this study aimed to investigate the presence of PCV‐3 in wild ungulates other than wild boar and in related hematophagous ectoparasites. One hundred and nine animals were sampled from different hilly and mountain areas of Friuli Venezia Giulia, including 9 chamois (Rupicapra rupicapra), 17 red deer (Cervus elaphus), 4 mouflons (Ovis musimon), 50 roe deer (Capreolus capreolus) and 29 wild boars (Sus scrofa). Additionally, host‐matched ectoparasites were collected when present. Porcine circovirus 3 was diagnosed using molecular techniques and sequencing. This study results confirmed the high PCV‐3 occurrence in wild boar and reported for the first time its presence, at low prevalence, in chamois and roe deer. Moreover, two ticks (Ixodes ricinus), one of which non‐engorged, collected from PCV‐3 negative roe deer, tested PCV‐3 positive. The genetic characterization of some of the strains collected from non‐swine hosts allowed to prove that, albeit clearly part of PCV‐3 species, they were genetically unique, demonstrating the absence of among‐samples contamination and thus confirming the actual presence of PCV‐3 genome in these new hosts. Therefore, this study highlights an unexpected broad PCV‐3 distribution and circulation in the wild, rising further questions on porcine circoviruses infectious cycle, epidemiology and origin, which will deserve additional investigations.  相似文献   

8.
Dirofilaria immitis and Dirofilaria repens are mosquito‐borne nematodes which infect primarily dogs as their main definitive hosts. They cause cardiopulmonary (D. immitis) or cutaneous (D. repens) dirofilariasis in canids and other carnivores and can accidentally be transmitted to humans where they can induce a variety of clinical outcomes depending on organ localization. Dirofilaria spp. infection in dogs was assessed using molecular methods (PCR and sequencing) to identify the different Dirofilaria species occurring in 200 dogs from Northern and Central Tunisia. The overall molecular prevalence of Dirofilaria spp. was 17.5% (35/200). The prevalence of D. immitis (14.5%) was significantly higher than for D. repens (3%). Molecular prevalence of D. immitis was significantly higher in suburban compared to urban and rural regions. There was no difference in molecular prevalence of D. immitis or D. repens according to the dogs’ (sex or use). Dirofilaria immitis amplicons (accession numbers KR676386 ) fall into the same clade with D. immitis from China, India and Taiwan. Comparison of the partial sequences of D. repensITS2 rDNA gene ( KR676387 ) revealed 99.6% similarity with D. repens reported in dogs from USA. It had also 97.6% similarity with D. repens from mosquitoes in Czech Republic. High dog parasite burdens should motivate both medical doctors and veterinarians to consider these frequent infections.  相似文献   

9.
Vertical transmission of Leishmania infantum was demonstrated in domestic mice captured close to the home of a patient with leishmaniasis. Leishmania infantum DNA was detected in 88.9% of synanthropic Mus musculus adult rodents and 29.2% of their unborn foetuses. Mother‐to‐infant transmission was observed in all females whose gestational stage was sufficiently advanced to allow foetal analysis (foetal length 2–2.5 cm). The infection rate in foetal samples ranged from 11.1% to 50.0%, with parasite loads of up to 6,481 parasites/5 mg tissue. A low density of Phlebotomus perniciosus was also found (0.2 specimen/CDC trap). Six infected mice captured in March were only 1.5 months old and could thus not have had contact with the vector. Vertical transmission thus appears to play a greater role in the spread of leishmaniasis than previously thought, particularly since rodents are natural hosts for the parasite and are prolific in nature.  相似文献   

10.
The prevalence of infection by Anaplasma spp. (including Anaplasma phagocytophilum) was determined using blood smear microscopy and PCR through screening of small ruminant blood samples collected from seven regions of Morocco. Co‐infections of Anaplasma spp., Babesia spp, Theileria spp. and Mycoplasma spp. were investigated and risk factors for Anaplasma spp. infection assessed. A total of 422 small ruminant blood samples were randomly collected from 70 flocks. Individual animal (breed, age, tick burden and previous treatment) and flock data (GPS coordinate of farm, size of flock and livestock production system) were collected. Upon examination of blood smears, 375 blood samples (88.9%) were found to contain Anaplasma‐like erythrocytic inclusion bodies. Upon screening with a large spectrum PCR targeting the Anaplasma 16S rRNA region, 303 (71%) samples were found to be positive. All 303 samples screened with the A. phagocytophilum‐specific PCR, which targets the msp2 region, were found to be negative. Differences in prevalence were found to be statistically significant with regard to region, altitude, flock size, livestock production system, grazing system, presence of clinical cases and application of tick and tick‐borne diseases prophylactic measures. Kappa analysis revealed a poor concordance between microscopy and PCR (k = 0.14). Agreement with PCR is improved by considering microscopy and packed cell volume (PCV) in parallel. The prevalence of double infections was found to be 1.7, 2.5 and 24% for Anaplasma‐Babesia, Anaplasma‐Mycoplasma and Anaplasma‐Theileria, respectively. Co‐infection with three or more haemoparasites was found in 1.6% of animals examined. In conclusion, we demonstrate the high burden of anaplasmosis in small ruminants in Morocco and the high prevalence of co‐infections of tick‐borne diseases. There is an urgent need to improve the control of this neglected group of diseases.  相似文献   

11.
To determine the prevalence of Bartonella species and identify which species of Bartonella naturally infects the striped field mouse (Apodemus agrarius) in the Republic of Korea (ROK), spleens from 200 mice were assayed by nested polymerase chain reaction (nPCR) targeting the RNA polymerase subunit beta (rpoB) gene and the 16S‐23S internal transcribed spacer (ITS) region for members of the genus Bartonella. Utilizing PCR techniques, the prevalence of Bartonella spp. ranged from 31.5% (63/200) to 62.0% (124/200) for the rpoB and ITS gene fragments, respectively. The most prevalent species, Bartonella grahamii, was assigned to 17 genotypes and closely related to the zoonotic pathogens, B. taylorii, B. tribocorum, B. phoceensis and B. henselae, which also were detected. Two Bartonella isolates (KRBG28 and KRBG32) were recovered from blood of A. agrarius captured in Gyeonggi Province, ROK. Comparison of the 16S rRNA, hemin‐binding protein E (hbpE), glutamate dehydrogenase 1 (gdh1), invasion‐associated protein B (ialB), cell division protein (ftsZ), citrate synthase (gltA), 60 kDa heat shock protein (groEL), rpoB gene fragments and the ITS region sequences from the isolates with GenBank was confirmed as B. grahamii. Phylogenetic analysis based on the alignment of concatenated sequences (4933 bp) of KRBG28 and KRBG32 clustered with B. grahamii, forming an independent clade between Asian and American/European B. grahamii genogroups.  相似文献   

12.
The dissemination of vector arthropods harbouring zoonotic pathogens through the uncontrolled transboundary trade of exotic and pet animals poses an important threat to Public Health. In the present report, we describe the introduction of pathogenic Rickettsia africae and R. aeschlimanni in ticks removed from imported tortoises in Qatar. A total of 21 ticks were collected from pet spur‐thighed tortoises (Testudo graeca) from Doha, May 2018, and studied for species identification and characterization of Rickettsia spp. Morphological and molecular analysis of ticks allowed their identification as Hyalomma aegyptium. Molecular analysis of partial ompA and gltA genes showed that Rickettsia sequences found on these ticks clustered with sequences classified as R. aeschilimanii and R. africae. Since pre‐adult stages of H. aegyptium also feed on humans, this tick species may play a role in the transmission of R. aeschilimanii and R. africae. We alert for the introduction of non‐native pets as vehicles for tick importation, known vectors for animal and human pathogenic agents. Importation of exotic species into non‐autochthonous countries deserves strict control to enforce robust surveillance and mitigate potential exotic diseases epidemics.  相似文献   

13.
The dynamics of bovine besnoitiosis were studied in an area where the disease is endemic. A four‐year longitudinal study was conducted for the first time in three infected beef cattle herds located in the Urbasa‐Andía Mountains (Navarra, Spain). Each herd was visited four to seven times, and clinical and serological prevalence rates and incidence rates were estimated. Clinical inspections to identify compatible clinical signs with the disease stages were conducted at the beginning and end of the study. Serological assessment was initially performed by ELISA. Seronegative animals with clinical signs and seropositive animals with relative index per cent (RIPC) values lower than 30 that did not increase during the study period were analysed by Western blot to optimize the sensitivity and specificity of the ELISA test. Clinical prevalence rates were slightly higher (62% on average) than the seroprevalence rates (50% on average), and tissue cysts located in the vestibulum vaginae and sclera were the most frequently detected clinical signs. The proportion of seropositive animals with clinical signs varied from 16.7% to 73.6% among the herds, and 17% of cattle with clinical signs proved to be seronegative by both serological tests. An average 22% serological incidence rate was also reported in addition to clinical incidence rates that varied from 12.5% to 16.7%. Additionally, parasitemia was investigated in the herd that showed the highest clinical and seroprevalence rates. Only one PCR positive blood sample was detected. Thus, the role that blood may play in parasite transmission needs to be further investigated. Infected herds maintained both high prevalence and incidence rates in the absence of control measures and a high number of parasite carriers. Finally, economic impact studies on reproductive and productive losses associated with besnoitiosis need to be performed to implement a cost–benefit control programme.  相似文献   

14.
Sarcocystosis is a parasitic disease caused by varying Sarcocystis species infecting humans and animals. It is commonly found in small ruminants causing pathogenic effects. This contributes to detrimental economic loss for local farmers and the local economy due this disease. Although the distribution of Sarcocystis can be found all over the world, the species infecting small ruminants in Tunisia is still unknown. Through this study, we aim to estimate the molecular prevalence of natural infection with Sarcocystis spp. in sheep and goats using molecular identification. Also, phylogenetic analyses were used to identify the different species of this parasite infecting small ruminants in northern Tunisia for the first time. DNA was extracted from 198 and 121, sheep and goats meat samples, respectively. The molecular prevalence of Sarcocystis spp. in sheep and goats was 58.6% (116/198) and 50.4% (61/121), respectively. Compared to the Noire de Thibar and cross‐breeds, the Barbarine sheep had the highest infection prevalence (63.4%) (=  .004). Five of the 116 positive samples were sequenced identifying Sarcocystis tenella from sheep. For goats, the sequencing results showed that five positive PCR products belonged to Sarcocystis capracanis species.  相似文献   

15.
Alpine Mycobacterium caprae isolates found in cattle and red deer display at least three genetic variations in the region of difference four (RD4) that can be used for further differentiation of the isolates into the subtypes ‘Allgäu’, ‘Karwendel’ and ‘Lechtal’. Each genomic subtype is thereby characterized by a specific nucleotide deletion pattern in the 12.7‐kb RD4 region. Even though M. caprae infections are frequently documented in cattle and red deer, little is known about the transmission routes. Hence, robust markers for M. caprae subtyping are needed to gain insight into the molecular epidemiology. For this reason, a rapid and robust multiplex PCR was developed for the simultaneous detection of three M. caprae RD4 subtypes and was used to subtype a total number of 241 M. caprae isolates from animals (145 cattle, 95 red deer and one fox) from Bavaria and Austria. All three subtypes occur spatially distributed and are found in cattle and in red deer suggesting transmission between the two species. As subtypes are genetically stable in both species it is hypothesized that the described genetic variations developed within the host due to ‘within‐host replication’. The results of this study recommend the genomic RD4 region as a reliable diagnostic marker for M. caprae subtype differentiation.  相似文献   

16.
Porcine brucellosis is a disease caused by Brucella suis, which is characterized by reproductive disorders in pigs. The number of cases of swine brucellosis has risen in many European countries, likely because of the presence of a wild reservoir of B. suis in wild boar. This study aimed at evaluating factors that may influence the probability of infection with Brucella spp. in wild boar and at assessing the impact of a previous contact with Brucella spp. on reproductive parameters of wild boar. Two hundred and four wild boar living in Extremadura (south‐western Spain) were studied. The presence of anti‐Brucella antibodies was determined using an indirect ELISA, while the presence of living bacteria in genital organs was evaluated through microbiological cultures. Sex, age, density of wild boar in summer and presence of outdoor pigs were selected as possible risk factors for being seropositive for Brucella spp. in wild boar. In addition, reproductive parameters such as breeding status or potential fertility in females and testis weight in males were estimated and related to the presence of anti‐Brucella antibodies. A total of 121 animals were seropositive, resulting in a prevalence of 59.3% (95% CI). In addition, seven isolates of B. suis biovar 2 were obtained. Wild boar density in summer, as well as age and sex, was proposed as factors to explain the probability of Brucella seroconversion, although wild boar density in summer was the key factor. Current measures of reproductive parameters were not influenced by a previous contact with Brucella spp. Isolation of B. suis confirms that wild boar could represent a risk to domestic pig health in the study area. Wild boar density seems to have a great influence in the probability of infections with B. suis and suggests that density management could be useful to control Brucella infection in wild boar.  相似文献   

17.
The number of natural infections with Mycobacterium caprae in wildlife and in cattle in the Bavarian and Austrian alpine regions has increased over the last decade. Red deer (Cervus elaphus) have been recognized as maintenance reservoir; however, the transmission routes of M. caprae among and from naturally infected red deer are unknown. The unexpected high prevalence in some hot spot regions might suggest an effective indirect transmission of infection. Therefore, this study was undertaken to diagnose the occurrence of M. caprae in faeces and secretions of red deer in their natural habitat. A total of 2,806 red deer hunted in this region during 2014–2016 were included in this study. After pathological examination, organs (lymph nodes, lung, heart), excretions and secretions (faeces, urine, saliva and tonsil swabs) were further investigated by qPCR specific for Mycobacterium tuberculosis complex (MTC), M. bovis and M. caprae. Samples tested positive by qPCR were processed for culturing of mycobacteria. In total, 55 (2.0%) animals were confirmed positive for M. caprae by pathological examination, PCR and culturing of the affected organ material. With the exception of one sample, all of the secretion and excretion samples were negative for mycobacteria of the Mycobacterium tuberculosis complex (MTC). From one red deer, M. caprae could be isolated from the heart sac as well as from the faeces. Whole‐genome sequencing confirmed that both strains were clonally related. This is the first confirmation that M. caprae can be shed with the faeces of a naturally infected red deer. However, further studies focusing on a higher number of infected animals, sample standardization and coordinated multiple sampling are necessary to improve the understanding of transmission routes under natural conditions.  相似文献   

18.
Chlamydiae are globally widespread obligate intracellular bacteria, which several species are a well‐recognized threat to human and animal health. In Australia, the most successful chlamydial species are the infamous koala pathogen C. pecorum, and C. psittaci, an emerging pathogen associated with zoonotic events. Little is known about infections caused by other chlamydial organisms in Australian livestock or wildlife. Considering that these hosts can be encountered by humans at the animal/human interface, in this study, we investigated genetic diversity of chlamydial organisms infecting Australian domesticated and wild ungulates. A total of 185 samples from 129 domesticated (cattle, horses, sheep, and pigs) and 29 wild (deer) ungulate hosts were screened with C. pecorum and C. psittaci species‐specific assays, followed by a screen with pan‐Chlamydiales assay. Overall, chlamydial DNA was detected in 120/185 (65%) samples, including all ungulate hosts. Species‐specific assays further revealed that C. pecorum and C. psittaci DNA were detected in 27% (50/185) and 6% (11/185) of the samples, respectively, however from domesticated hosts only. A total of 46 “signature” 16S rRNA sequences were successfully resolved by sequencing and were used for phylogenetic analyses. Sequence analyses revealed that genetically diverse novel as well as traditional chlamydial organisms infect an expanded range of ungulate hosts in Australia. Detection of the C. psittaci and C. pecorum in livestock, and novel taxa infecting horses and deer raises questions about the genetic make‐up and pathogenic potential of these organisms, but also concerns about risks of spill‐over between livestock, humans, and native wildlife.  相似文献   

19.
Brucella‐exposure and infection is increasingly recognized in marine mammals worldwide. To better understand the epidemiology and health impacts of Brucella spp. in marine mammals of Brazil, molecular (conventional PCR and/or real‐time PCR), serological (Rose Bengal Test [RBT], Competitive [c]ELISA, Serum Agglutination Test [SAT]), pathological, immunohistochemical (IHC) and/or microbiological investigations were conducted in samples of 129 stranded or by‐caught marine mammals (orders Cetartiodactyla [n = 124], Carnivora [n = 4] and Sirenia [n = 1]). Previous serological tests performed on available sera of 27 of the 129 animals (26 cetaceans and one manatee), indicated 10 seropositive cetaceans. Conventional PCR and/or real‐time PCR performed in cases with available organs (n = 119) and/or blood or swabs (n = 10) revealed 4/129 (3.1%) Brucella‐infected cetaceans (one of them with positive serology; the remaining three with no available sera). Pathological, IHC and/or microbiological analyses conducted in PCR/real‐time PCR and/or seropositive cases (n = 13) revealed Brucella‐type lesions, including meningitis/meningoencephalitis, pneumonia, necrotizing hepatitis, pericarditis and osteoarthritis in some of those animals, and positive IHC was found in all of them (excepting two live‐stranded animals without available organs). Brucella spp. culture attempts were unsuccessful. Our results demonstrated exposure, asymptomatic, acute and chronic Brucella sp. infection in several cetacean species in the Brazilian coast, highlighting the role of this pathogen in stranding and/or death, particularly in Clymene dolphin (Stenella clymene) and short‐finned pilot whale (Globicephala macrorhynchus) off Ceará State. Novel hosts susceptible to Brucella included the franciscana (Pontoporia blainvillei), the Guiana dolphin (Sotalia guianensis) and the spinner dolphin (Stenella longirostris). Additionally, three coinfection cases involving Brucella spp. and cetacean morbillivirus, Edwarsiella tarda and Proteus mirabilis were detected. To the best of our knowledge, this is the first long‐term and large‐scale survey of Brucella spp. in marine mammals of South America, widening the spectrum of susceptible hosts and geographical distribution range of this agent with zoonotic potential.  相似文献   

20.
Babesia ovis is a tick‐transmitted protozoan haemoparasite causing ovine babesiosis in sheep and goats leading to considerable economic loss in Turkey and neighbouring countries. There are no vaccines available, therapeutic drugs leave toxic residues in meat and milk, and tick vector control entails environmental risks. A panel of eight mini‐ and micro‐satellite marker loci was developed and applied to study genetic diversity and substructuring of Bovis from western, central and eastern Turkey. A high genetic diversity (He = 0.799) was found for the sample of overall Bovis population (n = 107) analyzed. Principle component analysis (PCoA) revealed the existence of three parasite subpopulations: (a) a small subpopulation of isolates from Aydin, western Turkey; (b) a second cluster predominantly generated by isolates from western Turkey; and (c) a third cluster predominantly formed by isolates from central and eastern Turkey. Two Bovis isolates from Israel included in the analysis clustered with isolates from central and eastern Turkey. This finding strongly suggests substructuring of a major Turkish population into western versus central–eastern subpopulations, while the additional smaller Bovis population found in Aydin could have been introduced, more recently, to Turkey. STRUCTURE analysis suggests a limited exchange of parasite strains between the western and the central–eastern regions and vice versa, possibly due to limited trading of sheep. Importantly, evidence for recombinant genotypes was obtained in regionally interchanged parasite isolates. Important climatic differences between the western and the central/eastern region, with average yearly temperatures of 21°C versus 15°C, correspond with the identified geographical substructuring. We hypothesize that the different climatic conditions may result in variation in the activity of subpopulations of Rhipicephalus spp. tick vectors, which, in turn, could selectively maintain and transmit different parasite populations. These findings may have important implications for vaccine development and the spread of drug resistance.  相似文献   

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