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1.
The genus pestivirus of the family flaviviridae consists of four recognized species: bovine viral diarrhoea virus 1 (BVDV‐1), bovine viral diarrhoea virus 2 (BVDV‐2), classical swine fever virus and border disease virus. A new putative pestivirus species tentatively named as either ‘HoBi‐like pestivirus’ or BVDV‐3 has recently been identified in Brazil, Italy and Thailand. Despite reports of serological evidence of BVDV in Bangladesh, the types of the virus circulating in cattle have not been identified. We conducted surveillance in cattle from May 2009 to August 2010 in three government veterinary hospitals to characterize BVDV in cattle of Bangladesh. We tested serum for BVDV using an antigen‐capture ELISA. Of 638 cattle samples, 3% (16/638) tested positive for BVDV antigen. The ELISA‐positive samples were selected for further molecular detection and characterization of BVDV. Molecular analysis of the partial 5′ untranslated region (UTR) nucleotide sequences of BVDV‐positive samples identified the rare HoBi‐like pestivirus or BVDV‐3 virus circulating in cattle of Bangladesh. The identification of this rare HoBi‐like pestivirus or BVDV‐3 strain in Bangladesh warrants further surveillance to evaluate its impact on livestock production.  相似文献   

2.
The ruminant pestiviral species BVDV ‐1, BVDV ‐2 and BDV , along with the putative species HoBi‐like, may cause substantial economic losses in cattle, sheep and goats. Brazil's large size, variable biomes and wide range of ruminant animal production within different geographic regions suggest that the presence and prevalence of ruminant pestivirus may differ by regions within Brazil. This study investigated the genetic diversity of ruminant pestiviruses and determined the frequency of active infections within two states of the Northeast Region of Brazil, Maranhão and Rio Grande do Norte. Serum samples from 16,621 cattle and 2,672 small ruminants from 569 different herds residing in this region were tested by RT ‐PCR followed by DNA sequencing. Seventeen positive cattle were detected (0.1%) from fifteen different herds (2.64%). All isolates were classified as HoBi‐like pestiviruses based on phylogenetic analysis. All small ruminant samples tested negative. The findings presented herein suggest that the Northeast Region of Brazil has a uniquely high prevalence of HoBi‐like viruses. The increasing reports of HoBi‐like viruses detected in cattle in the field suggest that natural infection with these viruses may be more widespread than previously thought. The identification of HoBi‐like viruses as the most prevalent type of ruminant pestivirus circulating in the Northeast Region of Brazil indicates the need for both continued monitoring and determination of the extent of economic losses associated with HoBi‐like virus infections. In addition, it must be taken into account in the choice of diagnostic tests and in vaccine formulations.  相似文献   

3.
Control of bovine viral diarrhoea (BVD) in Belgium is currently implemented on a voluntary basis at herd level and mainly relies on detection and culling of persistently infected (PI) animals. The present field study was conducted during the winter of 2010/2011 to assess the performances of diagnostic assays used in the testing scheme for BVD as proposed by the two Belgian regional laboratories. Individual blood samples were collected from 4972 animals, and individual samples from the same herd were pooled (maximum of 30 individual samples per pool) and screened for the presence of Bovine Viral Diarrhoea Virus (BVDV)‐specific RNA using a commercial real‐time RT‐PCR test (ADIAGENE). Individual samples from positive pools were then tested in parallel with the same RT‐PCR test and with an antigen‐capture ELISA test (IDEXX) to detect viremic animals. This study demonstrated that individual results differed according to the type of assay used (P < 0.001): 140 animals (2.8%) were positive by RT‐PCR and 72 (1.4%) by antigen‐ELISA. A second blood sample was taken 40 days later from 74 PCR positive animals to detect persistent viremia: 17 (23%) of these were still PCR positive and considered to be PI and the 57 that no longer tested positive were assumed to be transiently infected (TI) animals. All PI animals were positive also by antigen‐ELISA at both time points. Among TI animals, 10 (16%) were positive by antigen‐ELISA at the first but none at the second sampling. A highly significant difference in cycle threshold (Ct) values obtained by RT‐PCR was observed between PI and TI animals. ROC analysis was performed to establish thresholds to confirm with high probability that an animal is PI, based on the result of RT‐PCR test performed on a single individual blood sample.  相似文献   

4.
Recently, a putative new pestivirus species, provisionally named as Atypical Porcine Pestivirus (APPV ), was associated with the congenital tremor in piglets in North America and consequently in Europe and Asia. The present research aimed to describe the detection and characterization of APPV employing NS 5B gene partial sequencing, gross pathology and histologic examination of piglets displaying congenital tremor from two different farms of Southern Brazil. No gross lesions were observed, and the histological findings revealed moderate vacuolization of the white matter of the cerebellum. RT ‐PCR followed by DNA sequencing and a phylogenetic analysis confirmed the presence of APPV in samples from the two farms, which the samples were distinct in nature. Phylogenetic reconstruction reinforced the high genetic variability within the APPV s previously reported. This is the first report of APPV in South America suggesting that this new group of viruses may be widespread in swine herds in other countries as it is in Brazil.  相似文献   

5.
The natural infections of HoBi‐like pestiviruses in cattle have been reported in South America, Europe and Asia. In China, although the detections of HoBi‐like pestivirus have been reported, the epidemiological investigation was limited. From January 2014 to October 2015, several flocks of sheep/goats in Henan province in central China suffered respiratory diseases which were recovered slowly after antibiotics treatment. To test whether it is the HoBi‐like pestivirus caused this symptom, 49 serum samples and 22 nasal swabs were then collected for analysis by serology and RT‐PCR. Serological result revealed that prevalence of pestivirus in small ruminants was 12.2% (6/49) in central China. Sequence analysis of partial 5′‐UTR nucleotides of pestivirus‐positive samples suggested that HoBi‐like pestivirus might have circulated in sheep/goats of China for a period and have evolved into new genotype clusters. It is apparent that the study provides the molecular evidence of natural infections in goat/sheep species with HoBi‐like pestiviruses in China.  相似文献   

6.
Summary Two European laboratories independently detected atypical bovine pestiviral nucleic acids in three commercial batches of foetal bovine serum (FBS) that was claimed by the producers to be of Australian origin. Additional batches of FBS were obtained directly from Australia to exclude possible contamination of the Australian FBS with that of South American origin during manufacturing/packaging in European countries. RT‐PCR amplification of partial 5′untranslated region and the complete Npro gene yielded a specific band with expected size, which was confirmed by DNA sequencing. Bayesian analysis of sequence data demonstrated a closer phylogenetic relation of the newly detected atypical bovine pestiviruses to those of South American origin, which were related to the recognized bovine pestivirus species, bovine viral diarrhoea virus. Taken together, the results indicated the presence of atypical bovine pestiviruses in the Australian FBS, and most likely in Australian Continent.  相似文献   

7.
Bovine cysticercosis (BC) is an important disease because of its zoonotic nature. There is a significant variation in the prevalence of BC in different countries, ranging from <0.01% to more than 20%. In this study, we followed the changes of BC prevalence in Israel during the last four decades and examined its association with import of live cattle. During 1973–2007, 629 549 cattle were subjected to post‐mortem inspection conducted in ‘Marbek’ slaughterhouse located in the south of Israel. A specific comparison was made between the prevalence of BC in local and imported cattle during 2003–2007. Of 629 549 cattle, 2568 were infected with Cysticercus bovis (0.4%). From 1980, there was a gradual decrease in the prevalence of BC (R2 = 0.53) with exceptional peaks. Moreover, from 1973 to 1998, only 4% of the documented cases appeared in outbreaks as opposed to 38% after 1998 when mass importation of live cattle to Israel was initiated. All of these late outbreak cases appeared in imported cattle of which 95% originated from Australia. During the years 2002–2007, importation from Australia was found as a significant risk factor for infection with BC, with prevalence in these cattle reaching 1.8% in 2006. The time from importation to BC detection suggests that infection occurred either in Australia or during the transport into Israel. We conclude that despite a reduction in the prevalence of BC as a result of a possible improvement in sanitary conditions at the farms, meticulous meat inspection is still essential in Israel and possibly in other developed countries exporting and importing live cattle.  相似文献   

8.
The clinical features and economic impact of the infection caused by an emerging group of pestiviruses, namely HoBi‐like pestivirus, in a cattle herd of southern Italy are reported. In 2011, the virus was first associated with respiratory disease, causing an abortion storm after 1 year and apparently disappearing for the following 3 years after persistently infected calves were slaughtered. However, in 2014, reproductive failures and acute gastroenteritis were observed in the same herd, leading to a marked decrease of productivity. A HoBi‐like strain closely related to that responsible for previous outbreaks was detected in several animals. Application of an intensive eradication programme, based on the detection and slaughtering of HoBi‐like pestivirus persistently infected animals, resulted in a marked improvement of the productive performances.  相似文献   

9.
Bovine viral diarrhoea virus (BVDV) causes one of the most important diseases of cattle in terms of economic costs and welfare. The aims were to estimate herd prevalence and to investigate the factors associated with antibodies in bulk tank milk (BTM) in dairy herds through a matched case–control study. To estimate herd prevalence, BTM samples were randomly selected (n = 314) from a population (N = 1604). The true prevalence of BVDV was 24.3% (CI 95% = 20.1–29.3%). For the case–control study, BVDV antibody‐positive herds (high antibody titres) were classified as cases (n = 21) and matched (n = 63) by milk production with herds presenting low antibody titres (ratio of 1 : 3). Three multivariable models were built: 1) full model, holding all 21 variables, and two models divided according to empirical knowledge and similarity among variables; 2) animal factor model; and 3) biosecurity model. The full model (model 1) identified: age as a culling criteria (OR = 0.10; CI 95% = 0.02–0.39; < 0.01); farms that provided milk to other industries previously (OR = 4.13; CI 95% = 1.17–14.49; = 0.02); and isolation paddocks for ill animals (OR = 0.14; CI 95% = 0.01–0.26; = 0.02). The biosecurity model revealed a significant association with the use of natural mating (OR = 9.03; CI 95% = 2.14–38.03; < 0.01); isolation paddocks for ill animals (OR = 0.06; CI 95% = 0.05–0.83; = 0.03); years providing milk for the same industry (OR = 0.94; CI 95% = 0.91–0.97; = 0.02); and direct contact over fences among cattle of neighbouring farms (OR = 5.78; CI 95% = 1.41–23.67; = 0.04). We recommend the application of grouping predictors as a good choice for model building because it could lead to a better understanding of disease–exposure associations.  相似文献   

10.
The genus Pestivirus of the family Flaviviridae consists of four recognized species: Bovine viral diarrhoea virus 1 (BVDV‐1), Bovine viral diarrhoea virus 2 (BVDV‐2), Classical swine fever virus (CSFV) and Border disease virus (BDV). Recently, atypical pestiviruses (‘HoBi’‐like pestiviruses) were identified in batches of contaminated foetal calf serum and in naturally infected cattle with and without clinical symptoms. Here, we describe the first report of a mucosal disease‐like clinical presentation (MD) associated with a ‘HoBi’‐like pestivirus occurring in a cattle herd. The outbreak was investigated using immunohistochemistry, antibody detection, viral isolation and RT‐PCR. The sequence and phylogenetic analysis of 5′NCR, Npro and E2 regions of the RT‐PCR positive samples showed that four different ‘HoBi’‐like strains were circulating in the herd. The main clinical signs and lesions were observed in the respiratory and digestive systems, but skin lesions and corneal opacity were also observed. MD characteristic lesions and a pestivirus with cytopathic biotype were detected in one calf. The present study is the first report of a MD like presentation associated with natural infection with ‘HoBi’‐like pestivirus. This report describes the clinical signs and provides a pathologic framework of an outbreak associated with at least two different ‘HoBi’‐like strains. Based on these observations, it appears that these atypical pestiviruses are most likely underdiagnosed in Brazilian cattle.  相似文献   

11.
The aim of this work was to investigate the effect of pre‐infection with bovine viral diarrhoea virus (BVDV) on thymus immune cells from calves challenged with bovine herpesvirus 1 (BHV‐1). Twelve Friesian calves, aged 8 to 9 months, were inoculated with non‐cytopathic BVDV‐1. Ten of them were subsequently challenged with BHV‐1 and euthanized in batches of two at 1, 2, 4, 7 or 14 dpi with BHV‐1. The other two calves were euthanized prior to the second inoculation and were used as BVDV‐infected controls. A further 10 calves were inoculated solely with BHV‐1 and euthanized at the same time points. Two calves were not inoculated with any agent and were used as negative controls. Quantitative changes in immune cells were evaluated with immunohistochemical methods to compare coinfected calves and calves challenged only with BHV‐1. The results of this study pointed out BVDV as responsible for the thymic lesions observed in the experiment as well as for the majority of immunopathologic changes, including a downregulation of Foxp3 lymphocytes and TGFβ, which reverted as BVDV was cleared, and an overexpression of medullary CD8+ T cells. However, despite not inducing evident lesions in the thymus, BHV‐1 seemed to prompt some immune alterations. Collectively, these data contribute to the knowledge on the immunopathologic alterations of the thymus during BVDV infections, and its importance in the development of secondary infections.  相似文献   

12.
A cross‐sectional study was conducted to determine the species of Anaplasma spp. and estimate its prevalence in cattle of the three main cattle‐producing Galapagos Islands (Santa Cruz, San Cristóbal and Isabela) using indirect PCR assays, genetic sequencing and ELISA . Ticks were also collected from cattle and scanned for 47 tick‐borne pathogens in a 48 × 48 real‐time PCR chip. A mixed effects logistic regression was performed to identify potential risk factors explaining Anaplasma infection in cattle. A. phagocytophilum was not detected in any of the tested animals. Genetic sequencing allowed detection of A. platys ‐like strains in 11 (36.7%) of the 30 Anaplasma spp.‐positive samples analysed. A. marginale was widespread in the three islands with a global between‐herd prevalence of 100% [89; 100]95%CI and a median within‐herd prevalence of 93%. A significant association was found between A. marginale infection and age with higher odds of being positive for adults (OR = 3.3 [1.2; 9.9]95% Bootstrap CI ). All collected ticks were identified as Rhipicephalus microplus. A. marginale , Babesia bigemina , Borrelia theileri and Francisella ‐like endosymbiont were detected in tick pools. These results show that the Galapagos Islands are endemic for A. marginale .  相似文献   

13.
Currently, five Bartonella species and an expanding number of Candidatus Bartonella species have globally been reported in ruminants. Likewise, different Bartonella genotypes were identified. However, studies relating to ruminant‐associated Bartonella in Brazil are scarce. The current study aimed to assess the prevalence and genetic diversity of Bartonella in cattle, buffaloes and associated ectoparasites in Brazil. For this purpose, EDTA‐blood samples from 75 cattle and 101 buffaloes were sampled. Additionally, 128 Rhipicephalus microplus and one Amblyomma sculptum ticks collected from cattle, and 197 R. microplus, one A. sculptum and 170 lice (Haematopinus tuberculatus) collected from buffaloes were included. Bartonella DNA was initially screened through an HRM real‐time PCR assay targeting the 16S–23S internal transcribed spacer (ITS), and the positive samples were submitted to an additional HRM assay targeting the ssrA gene. The HRM‐positive amplicons were sequenced, and the nucleotide identity was assessed by BLASTn. Bartonella spp.‐positive DNA samples were analysed by conventional PCR assays targeting the gltA and rpoB genes, and then, the samples were cloned. Finally, the phylogenetic positioning and the genetic diversity of clones were assessed. Overall, 21 of 75 (28%) cattle blood samples and 13 of 126 (10.3%) associated ticks were positive for Bartonella bovis. Out of 101 buffaloes, 95 lice and 188 tick DNA samples, one (1%) buffalo and four (4.2%) lice were positive for Bartonella spp. Conversely, none of the ticks obtained from buffaloes were positive for Bartonella. The Bartonella sequences from buffaloes showed identity ranging from 100% (ITS and gltA) to 94% (ssrA) with B. bovis. In contrast, the Bartonella DNA sequences from lice were identical (100%) to uncultured Bartonella sp. detected in cattle tail louse (Haematopinus quadripertusus) from Israel in all amplified genes. The present study demonstrates the prevalence of new B. bovis genotypes and a cattle lice‐associated Bartonella species in large ruminants and their ectoparasites from Brazil. These findings shed light on the distribution and genetic diversity of ruminant‐ and ectoparasite‐related Bartonella in Brazil.  相似文献   

14.
In present investigation, etiopathological characterization of upper gastrointestinal tract (GIT) tumours of cattle and buffaloes was undertaken. A total of 27 GIT wart‐like lesions in rumen, reticulum, mouth and oesophagus of cattle and buffaloes revealed the presence of small nodular to larger spherical or slender growths with thin base present on mucosa and ruminal pillar. Histopathologically, these cases were diagnosed as fibropapilloma/papilloma. This is the first world record on ruminal papillomatosis in buffaloes. Ruminal warts of cattle and buffaloes revealed the presence of BPV‐5, ‐1 & ‐2, which is the first report of presence of these BPVs in the ruminal warts from India. Quantitative real‐time PCR revealed that DNA samples of different GIT wart‐like lesions contained varying amount of BPV DNA copy numbers. Immunohistochemistry revealed that the PCNA and Ki67 immunopositivity was present in the basal and spinosum layer of the fibropapilloma/papilloma, indicating these as the cellular proliferation site. In conclusion, the present investigation revealed that BPV‐5, ‐1 & ‐2 are associated with certain ruminal wart‐like lesions/growths in cattle and buffaloes, and the basal and spinosum layer of the ruminal fibropapilloma/papilloma were cellular proliferation sites.  相似文献   

15.
Bovine papillomavirus (BPV) is a diverse group of double‐stranded DNA oncogenic viruses. BPVs are classically described as epitheliotropic, however, they have been detected in body fluids, such as blood and semen. The presence of BPV in these sites can have implications for the dissemination of BPV. The aim of this study was to verify the prevalence of BPV types in cattle blood. A total of 57 blood samples were analyzed by PCR using BPV type‐specific primers to BPVs 1–6 and 8–10, and subsequent sequencing. Sequencing quality was determined using Staden package with Phred 20. Similarity analysis was performed with BioEdit and BLAST programs to assess the identity with known BPV types. Statistical analysis was performed by Fisher's exact test. The results showed seven different types of BPVs in the blood, with the exception of BPV 5 and 9. This is the first study that demonstrates BPVs 3, 6, 8 and 10 DNA in cattle blood. BPVs 1 and 2 were the viral types most frequent in blood, while BPVs 4 and 10 were the least frequent types. All the samples showed co‐infection by at least two BPV types. These data suggest that several BPV types may infect blood cells at the same time and demonstrate the possibility that the BPV infection in non‐epithelial tissue can occur without restriction to one or two viral types. These results can contribute to future studies aimed at the control and prevention of papillomaviruses.  相似文献   

16.
Oxidative stress has negative impacts on the clinical outcomes of assisted reproduction techniques. The brain‐derived neurotrophic factor (BDNF) promotes the viability of nerve cells and is known to decrease oxidative stress and apoptosis in different cells. The aim of this study was to evaluate the effect of BDNF treatment on human sperm functions that are known to be essential for fertilisation. Our findings showed that treatment of human spermatozoa with 0.133 nM BDNF significantly increased the percentages of both total (= 0.001) and progressive (P < 0.01) motile sperm cells compared to those observed in the nontreated (control) group. We also showed that the mean fluorescence intensity of DCFH‐DA, as an indicator of intracellular reactive oxygen species, was significantly lower (P < 0.05) in spermatozoa treated with BDNF compared to the control group. Treatment of spermatozoa with BDNF significantly decreased the percentages of both dead (= 0.001) and apoptotic‐like sperm cells (P < 0.05) compared to the control group. On the other hand, BDNF treatment significantly increased the percentage of viable sperm cells compared to the control (= 0.001). In conclusion, BDNF has protective effects against oxidative stress in spermatozoa and could improve sperm functions that are essential for sperm–egg fusion and subsequent fertilisation.  相似文献   

17.
18.
Feline panleukopenia virus (FPV) and canine parvovirus (CPV) are two closely related viruses, which cause acute gastroenteritis in carnivores, and cats may be infected by strains of both viruses. The viruses are found worldwide and may have changing host ranges and genetic variation that can be found around the world in some cases. Here, we screened a Portuguese population of cats by a conventional PCR assay for the presence of FPV/CPV viruses in faecal samples and tissues between 2006–2008 and 2012–2014. The sequence analysis of the complete VP2 gene showed that 18 of 31 animals tested were positive for FPV DNA, and no case of CPV infection was detected. The analysis of specific DNA detected three new non‐synonymous substitutions in the VP2 gene that were found in single groups and were related to viruses reported elsewhere by phylogenetic analysis – some were related to Italian isolates, one was closely related to isolates from Vietnam and China, and two were related with older strains from the USA. The results of our study show that FPV circulated in the Portuguese cat population and as expected the found strains are slightly divergent from those reported previously.  相似文献   

19.
These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of tissue and blood protozoal infections in the pre‐ and post‐transplant period. Significant new developments in the field have made it necessary to divide the previous single guideline published in 2013 into two sections, with the intestinal parasites separated from this guideline devoted to tissue and blood protozoa. The current update reflects the increased focus on donor screening and risk‐based recipient monitoring for parasitic infections. Increased donor testing has led to new recommendations for recipient management of Toxoplasma gondii and Trypanosoma cruzi. Molecular diagnostics have impacted the field, with access to rapid diagnostic testing for malaria and polymerase chain reaction testing for Leishmania. Changes in Babesia treatment regimens in the immunocompromised host are outlined. The risk of donor transmission of free‐living amebae infection is reviewed. Changing immigration patterns and the expansion of transplant medicine in developing countries has contributed to the recognition of parasitic infections as an important threat to transplant outcomes. Medications such as benznidazole and miltefosine are now available to US prescribers as access to treatment of tissue and blood protozoa is increasingly prioritized.  相似文献   

20.
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   

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