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1.
Torque teno sus virus (TTSuV) is emergent in swine herds. Recent studies have shown an increased frequency of TTSuV2 in Porcine circovirus type 2 (PCV2)-associated diseases (PCVAD), which are endemic in many swine-producing countries, including Brazil. Coinfection with several other viral and bacterial agents results in an increased incidence of more severe PCVAD. Given the limited information on TTSuV and PCV2 coinfection, especially in Brazilian swine herds, this study made a preliminary estimation of the occurrence of coinfection in swine herds by testing samples from different categories. Between 2008 and 2009, 111 samples of feces and 23 serum samples from 5 swine herds were tested for PCV2 and TTSuVs and the results analyzed for associations between these agents. No significant differences in coinfection frequency were observed for PCV2 + TTSuV1 or for PCV2 + TTSuV2 between nursery piglets (P = 0.730), growing pigs (P = 0.331), or sows (P = 0.472). However, a significant difference was observed for PCV2 + TTSuV1 + TTSuV2 between nursery piglets and growing pigs (P = 0.004; Fisher’s exact test). Phylogenetic studies agreed with the grouping of TTSuV1 and TTSuV2 into 2 different clades, with no distinct pattern of clustering of these isolates with the animal categories.  相似文献   

2.
The objectives of this study were to (1) investigate the occurrence of hepatitis E virus (HEV) in pigs from large-scale and family-scale farms, (2) genetically characterize the strains isolated, and (3) study the pathogenesis of swine HEV infection via immunohistochemistry. A total of 50 pigs from 10 farms in Mato Grosso State, Brazil were divided according to type of production system into either large-scale farms (n?=?5) or family-scale farms (n?=?5). Samples of liver, gallbladder, small and large intestines, bile, and feces from the pigs were analyzed by nested PCR with primers targeting the ORF2 region of HEV and by immunohistochemistry. Of the eight HEV-positive samples from pigs of family-scale farms, phylogenetic analysis revealed that seven of the swine HEV isolates clustered with subtype 3b of genotype 3 and one isolate was categorized with subtype 3 f. The HEV antigen was detected mainly in the small intestine samples from family-scale farms, suggesting an early stage HEV infection. HEV was not detected in the samples of pigs from large-scale farms, reinforcing the need for additional studies to evaluate the risk of transmission of HEV to humans from pigs from family-scale farms in Mato Grosso State.  相似文献   

3.
Mycoplasma suis, the etiological agent of swine hemoplasmosis, is an epicellular bacterium that adheres to the surface of pig erythrocytes leading to deformations of the target cells. Little is known about the occurrence of M. suis in wild swine populations around the world, its economic impact on swine herds, and the risk of human infection. The aim of this study was to investigate, by quantitative real-time PCR (qPCR) based on the 16S rRNA gene, the occurrence of M. suis in a captive population of white-lipped peccaries (100 Tayassu pecari) and in free-living wild boars (14 Sus scrofa) in Brazil. None of the white-lipped peccaries were positive for M. suis, whereas seven (50%) wild boars were positive in qPCR assays. The quantification of M. suis-16S rRNA copies/μL ranged from 1.42 × 10° to 3.906 × 101 in positive animals, indicating a low bacteremia and a chronic carrier status in free-living wild boars. In conclusion, M. suis might be a non-frequent pathogen in wild suids maintained in captivity. Despite the low bacteremia, the prevalence of M. suis in wild boar population in Brazil seems to be high.  相似文献   

4.
Brucella suis has been recognized as the major etiological agent of human brucellosis in areas free from Brucella melitensis infection. However, with changes in swine management, the occurrence of swine brucellosis has decreased as has the human incidence of B. suis infection. A swine brucellosis outbreak within a herd from Jaboticabal (S?o Paulo, Brazil) was detected in July 2006. The herd comprised approximately 300 sows and 1,500 finishing animals. Many sows within this herd experienced abortions, while others exhibited vaginal discharge; three sows suffered posterior paralysis. Among 271 sows, 254 (93.7%) tested positive for brucellosis by complement fixation, and among 62 randomly bled finishing animals, 17 (27.4%) also tested positive. The B. suis biovar 1 was cultured from 14 aborted fetuses and six sows. Brucella was identified using routine methods. Fourteen farm workers were tested using agglutination tests, with three workers showing evidence of Brucella antibody titers. A 39-year-old woman, who worked with maternal pigs and had direct contact with aborted fetuses, presented an agglutinating titer of 480?IU/mL and displayed clinical signs of infection. Our findings suggest that despite a reduction of swine brucellosis throughout Brazil, B. suis infection still occurs, thereby posing a zoonotic risk.  相似文献   

5.
Influenza is a viral disease that affects human and several animal species. In Brazil, H1N1, H3N2 and 2009 pandemic H1N1 A(H1N1)pdm09 influenza A viruses (IAV) circulate in domestic swine herds. Wild boars are also susceptible to IAV infection but in Brazil until this moment there are no reports of IAV infection in wild boars or in captive wild boars populations. Herein the occurrence of IAV in captive wild boars with the presence of lung consolidation lesions during slaughter was investigated. Lung samples were screened by RT-PCR for IAV detection. IAV positive samples were further analyzed by quantitative real-time PCR (qRRT-PCR), virus isolation, genomic sequencing, histopathology and immunohistochemistry (IHC). Eleven out of 60 lungs (18.3%) were positive for IAV by RT-PCR and seven out of the eleven were also positive for A(H1N1)pdm09 by qRRT-PCR. Chronic diffuse bronchopneumonia was observed in all samples and IHC analysis was negative for influenza A antigen. Full genes segments of H1N2 IAV were sequenced using Illumina's genome analyzer platform (MiSeq). The genomic analysis revealed that the HA and NA genes clustered with IAVs of the human lineage and the six internal genes were derived from the H1N1pdm09 IAV. This is the first report of a reassortant human-like H1N2 influenza virus infection in captive wild boars in Brazil and indicates the need to monitor IAV evolution in Suidae populations.  相似文献   

6.
Several strains of porcine bocaviruses have been reported worldwide since their first detection in Sweden in 2009. Subsequently, the virus has been reported to be associated with gastrointestinal and respiratory signs in weaner and grower pigs. Although Malaysia is host to a self-sufficient swine livestock industry, there is no study that describes porcine bocavirus in the country. This report is the first to describe porcine bocavirus (PBoV) in Malaysian swine herds. PBoV was identified in various tissues from sick and runt pigs using the conventional PCR method with primers targeting conserved regions encoding for the nonstructural protein (NS1) gene. Out of 103 samples tested from 17 pigs, 32 samples from 15 pigs were positive for porcine bocavirus. In addition, a higher detection rate was identified from mesenteric lymph nodes (52.9%), followed by tonsil (37.0%), and lungs (33.3%). Pairwise comparison and phylogenetic analyses based on a 658-bp fragment of NS1 gene revealed that the Malaysian PBoV strains are highly similar to PBoV3 isolated in Minnesota, USA. The presence of porcine bocavirus in Malaysia and their phylogenetic bond was marked for the first time by this study. Further studies will establish the molecular epidemiology of PBoV in Malaysia and clarify pathogenicity of the local isolates.  相似文献   

7.
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8.
ABSTRACT: Picobirnaviruses (PBV) are small, non-enveloped viruses with a bisegmented double-stranded RNA genome. In this study a PBV strain, PBV/Horse/India/BG-Eq-3/2010, was identified in the faeces of a 10 month old weaned female foal with diarrhoea in January 2010 from Kolkata, India. Surprisingly, sequence comparison and phylogenetic analysis of a short stretch of the RNA dependent RNA polymerase gene revealed close genetic relatedness (> 98% nucleotide identity) to a human genogroup I PBV strain (Hu/GPBV1) detected earlier from the same part of India. Our observations together with earlier findings on genetic relatedness between human and animal PBV warrant further studies on zoonotic potential.  相似文献   

9.
Streptococcus suis is an important pathogen in the swine industry. This article is the first to report the occurrence, risk factors, serotype distribution, and antimicrobial susceptibility of S. suis recovered from employees and environmental samples of swine slaughterhouses in Brazil. Tonsillar swabs from all 139 pig-slaughtering employees and 261 environmental swabs were collected for detection of S. suis and serotyping by monoplex and multiplex polymerase chain reaction, respectively. Antimicrobial susceptibility was determined by the disk-diffusion method. Although S. suis was not detected in any of the tested employees, it was isolated from 25% of the environmental samples. Significant differences (P < 0.05) in the occurrence of S. suis were observed between slaughterhouses and between areas of low, medium, and high risk. The most frequent serotypes were 4 and 29, each accounting for 12% of the isolates, followed by 5, 12, 21, and 31, each accounting for 6%. High rates of susceptibility to the antimicrobials doxycycline (100%), ceftiofur (94%), ampicillin (81%), and cephalexin (75%) were observed. However, multidrug resistance was observed in all the isolates. Because S. suis is present in the environment of swine slaughterhouses, on carcasses and knives, as well as on the hands of employees in all areas, all employees are at risk of infection.  相似文献   

10.
Hepatitis E is an infectious disease which virus (HEV) is highly disseminated in swine herd populations. Sporadic acute human hepatitis E cases have been associated to genotype 3 and 4 strains of HEV also reported in swine populations of endemic and non-endemic areas. With the aim to evaluate the incidence of animals with current infection of HEV, 115 bile samples were collected from three slaughterhouses under inspection by Animal Sanitary Protection Agency of Rio de Janeiro, Brazil. In parallel, effluent samples were collected from six sewage pipe exit sites of two slaughterhouses. HEV RNA was detected in 11 out of 115 (9.6%) bile samples collected and three waste samples from one slaughterhouse. Viral loads observed for bile samples varied from 10(1)-10(5) genome copies/mL and for effluent samples mean load was 10(2) genome copies/mL. Sequencing and phylogenetic analysis classified samples within genotype 3 subtype 3b closely related to the sample obtained from the first reported autochthonous human case and samples from swine of commercial herds in Brazil. Our data demonstrates that although most animals achieve slaughter age (around 20 weeks old) already immune to HEV, a significant number of animals are with current infection at commercial age. Further studies should be addressed to consider risk analysis and possible evaluation of inspection regulations considering food safety measures regarding hepatitis E zoonotic aspect in Brazil.  相似文献   

11.
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12.
Long pentraxin 3 (PTX3) is a conserved pattern-recognition secreted protein and a host-defence-related component of the humoral innate immune system. The aim of the present study was to characterize swine PTX3 (SwPTX3) protein expression in influenza virus infected pigs. First, we performed in silico studies to evaluate the cross-reactivity of PTX3 human antibodies against SwPTX3. Secondly, we used in vitro analysis to detect SwPTX3 presence in swine bone marrow dendritic cells (SwBMDC) upon stimulation with different agents by Western blot and immunofluorescence. Finally, the levels of SwPTX3 were assessed in experimental infection of pigs with different strains of influenza virus. This is a novel study where the expression of SwPTX3 was evaluated in the context of a pathogen infection. The initial characterization of SwPTX3 in influenza virus infected pigs contributes to understand the role of PTX proteins in the immune response.  相似文献   

13.
Porcine circovirus-2 and concurrent infections in the field   总被引：27，自引：0，他引：27  
Porcine circovirus-2 (PCV-2) is the necessary cause of post-weaning multisystemic wasting syndrome (PMWS) in swine; however, a variety of co-factors, including other infectious agents, are thought to be necessary in the full expression of disease. Porcine parvovirus (PPV) was found in the inoculum used in the first experiments to reproduce PMWS in gnotobiotic swine. Retrospective and prospective studies in the field and laboratory have demonstrated PCV-2 can act synergistically with PPV to enhance the severity of PMWS. PCV-2 has been shown to play a role in the porcine infectious disease complex (PRDC). Other co-infecting agents with PCV-2 in the lung include, porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV) and Mycoplasma hyopneumoniae. Exposure of pregnant sows to PPV, PRRSV, or encephalomyocarditis virus may interact with PCV-2 infected foetuses. The severity of hepatic lesions in PCV-2 infected pigs may be enhanced by co-infection with agents such as swine hepatitis E virus and Aujezsky's disease virus. Additional studies are required to determine the mechanistic basis for the interaction of PCV-2 with other agents in the pathogenesis of the various clinical syndromes that have been associated with PCV-2 infection.  相似文献   

14.
The present study describes detection of picobirnavirus (PBV) in faecal samples from bovine and buffalo calves employing the polyacrylamide gel electrophoresis (PAGE). A total of 136 faecal samples from buffalo (n = 122) and cow calves (n = 14) exhibiting clinical signs of diarrhoea and from healthy calves were collected during 2007–2010 from subtropical (central India) and tarai area of western temperate Himalayan foothills (Uttarakhand). The dsRNA nature of the virus was confirmed by nuclease treatment (RNase A, RNaseT1 and DNase 1). PAGE results confirmed 3.67% (5/136) positivity for PBV, showing a typical genomic migration pattern with two discrete bands with size of approximately 2.4 and 1.7 kbps for the larger and smaller segments, respectively. Among the five PBV samples identified, three were from buffalo calves and one from cow calf exhibiting clinical signs of acute diarrhoea, while one sample from non-diarrhoeic buffalo calf also showed the presence of PBV. None of the samples showed dual infection of rotavirus and PBV. The preliminary findings indicate sporadic incidences of PBV in bovine calves and emphasize the need for the development of better diagnostics for early detection and genetic characterization of these emerging isolates of farm animals of economic significance.  相似文献   

15.
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16.
Porcine circovirus 2 (PCV2) is a recently identified agent that has been associated with postweaning multisystemic wasting syndrome (PMWS) in swine populations. In this report, the potential spectrum of disease associated with PCV2 is expanded by evidence of vertical transmission and associated reproductive failure. PCV2 was isolated from a litter of aborted piglets from a farm experiencing late-term abortions and stillbirths. Severe, diffuse myocarditis was present in 1 piglet associated with extensive immunohistochemical staining for PCV2 antigen. Variable amounts of PCV2 antigen were also present in liver, lung, and kidney of multiple fetuses. The presence of other agents that have been associated with fetal lesions and abortion in swine, including porcine parvovirus, porcine reproductive respiratory syndrome virus, encephalomyocarditis virus, and enterovirus, could not be established.  相似文献   

17.
Hepatitis B virus (HBV) is the prototype of the Orthohepadnavirus genus and represents an important cause of chronic hepatitis, liver cirrhosis, and hepatic cancer in humans worldwide. To verify the occurrence and genetic variability of orthohepadnavirus among neotropical bats, we tested 81 liver samples of New World bats from São Paulo State, Southeastern Brazil, collected during 2012. PCR, sequencing, and phylogenetic analysis of Surface/Polymerase and Core viral genes confirmed the occurrence of the first isolate of bat orthohepadnavirus detected in South America. These results may contribute to subsequent studies of the origin, variability, host species, and evolution of bat orthohepadnaviruses in South America.  相似文献   

18.
SIV与PRRSV、CSFV、PCV-2和PRV交叉感染的检测   总被引：2，自引：0，他引：2  
采用RT-PCR方法对37份疑似猪流感病毒(SIV)感染病料进行了病原学检测。同时,还运用PCR和RT-PCR方法对SIV阳性病料进行了猪繁殖与呼吸综合征病毒(PRRSV)、猪瘟病毒(CSFV)、猪圆环病毒2型(PCV-2)和猪伪狂犬病毒(PRV)目的基因片段的扩增。结果,扩增出了SIV特异目的基因片段,且4份病料都为混合感染,感染状况分别为SIV/PRRSV/PRV,SIV/CSFV/PRRSV三重感染,SIV/PCV-2和SIV/PRRSV二重感染。  相似文献   

19.
Torque teno sus virus (TTSuV) is responsible for the infection of pig herds around the world. The aim of this study was to analyse the presence of natural infection by both species of TTSuV in suckling piglets from major pig-producing regions of Brazil. Faecal samples (n?=?135) from 1 to 3-week-old suckling piglets from the Southern, Southeast and Midwest regions of Brazil were analysed by PCR assay to detect TTSuV1 and 2. TTSuV1 and 2 DNA was identified in 65 (48.1?%) and 23 (17?%) of piglet faecal samples, respectively. Co-infection by both species of TTSuV was detected in 17 (12.6?%) samples. Detection of TTSuV1 was significantly higher than that of TTSuV2 in the three Brazilian regions together (p?<?0.05). Based on age of animals, TTSuV1 infection was statistically higher than TTSuV2 in each age group (p?<?0.05). For all of the age groups together, no statistical difference was detected in the number of TTSuV1 and 2 positive results (p?>?0.05). These findings revealed that TTSuV infection has disseminated in pig herds from different geographic Brazilian regions, and the presence of TTSuV in suckling piglet faecal samples suggested the early infection by the virus and the potential of these animals in spreading the virus.  相似文献   

20.
《Veterinary microbiology》2015,175(2-4):374-381
Genetic heterogeneity of Mycoplasma hyopneumoniae in pigs has been reported, however there has been limited reproducibility on the molecular methods employed so far. The aim of this study was to modify and standardize a high-resolution multiple locus variable number tandem repeat analysis (MLVA), to investigate the genetic variability of M. hyopneumoniae circulating in the United States of America (USA), Brazil, Mexico and Spain. The MLVA was standardized on the basis of the number of tandem repeats in two Mycoplasma adhesins, P97 and P146, which are proteins involved in the adherence of the pathogen to cilia. A total of 355 samples obtained from the four countries were analyzed. The Simpson's diversity index for the assay was D = 0.976 when samples from all countries were combined. A large number of MLVA types (n = 139) were identified, suggesting that multiple M. hyopneumoniae variants are circulating in swine. The locus P97 had 17 different types with 2–18 repeats. The P146 locus showed higher heterogeneity, with 34 different types, ranging from 7 to 48 repeats. MLVA types that presented more than 30 repeats in P146 were found in Spain and Brazil, while shorter repeats were observed in the USA and Mexico. This simplified MLVA method proved to be an efficient tool for typing M. hyopneumoniae with a high degree of stability, repeatability, and discriminatory power. In conclusion, M. hyopneumoniae showed a high variable number tandem repeat heterogeneity and this assay can be applied in molecular epidemiology investigations within farms and productions systems.  相似文献   

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