TitleAbstractYear(sorted ascending)
seroreactivity of peruvian sheep and goats to small ruminant lentivirus-ovine progressive pneumonia virus.sera from 3,369 sheep and 1,394 goats in peru were examined by agar-gel immunodiffusion for antibodies to ovine progressive pneumonia virus (oppv). the point prevalence rates for antibodies to oppv in sheep were 1.7% to 40.6% (mean, 19.02%) in the 7 flocks studied, whereas for goats, the point prevalence rates for antibodies that cross-reacted with oppv in 12 herds were 0.0% to 45.1%. for sheep, a direct association between increasing age and increasing seroreactivity to oppv was established, an ...19873105369
[diffuse interstitial pneumopathies caused by lentivirus (hiv-1) in humans and animals].lentiviruses belong to the retroviruses family (ie rna viruses with reverse transcriptase activity); they induce inflammatory and/or degenerative slowly progressive diseases, affecting various organs. some lentiviruses preferentially infect lymphocytes (hiv-1 and hiv-2, siv and fiv) and are associated with infectious and tumoral disorders. most lentiviruses induce a pulmonary disease, typically diffuse interstitial pneumonia. the visna/maedi-virus of sheep infects monocyte macrophage cells and t ...19901980153
immortalization of caprine fibroblasts permissive for replication of small ruminant establish immortalized caprine fibroblastic cell lines permissive for replication of small ruminant lentiviruses.19979185961
a new sensitive serological assay for detection of lentivirus infections in small ruminants.lentivirus infections in small ruminants represent an economic problem affecting several european countries with important sheep-breeding industries. programs for control and eradication of these infections are being initiated and require reliable screening assays. this communication describes the construction and evaluation of a new serological screening enzyme-linked immunosorbent assay (elisa) for the detection of antibodies to maedi-visna virus (mvv) in sheep and to caprine arthritis encepha ...199910473527
host range of small-ruminant lentivirus cytopathic variants determined with a selectable caprine arthritis- encephalitis virus pseudotype system.the small-ruminant lentiviruses ovine maedi-visna virus (mvv) and caprine arthritis-encephalitis virus (caev) cause encephalitis, progressive pneumonia, arthritis, and mastitis in sheep and goats. icelandic mvv strains, which are lytic in tissue culture, have a wide species distribution of functional receptors, which includes human cells. in contrast, functional receptors for the nonlytic caev co are absent from human cells. to determine if the wide species distribution of functional receptors i ...200111462010
genetic heterogeneity of small ruminant lentiviruses involves immunodominant epitope of capsid antigen and affects sensitivity of single-strain-based immunoassay.the pol and gag gene fragments of small ruminant lentivirus field isolates collected in the last decade in italy were amplified, sequenced, and analyzed. phylogenetic analysis revealed that the majority of ovine isolates form a distinct cluster more similar to caprine lentivirus prototypes than to the visna virus prototype. these findings confirm and extend those reported by leroux et al. (arch. virol., 142:1125-1137, 1997). moreover, we observed that a variable region of gag, included in the fr ...200212093681
phylogenetic analysis of small-ruminant lentivirus subtype b1 in mixed flocks: evidence for natural transmission from goats to sheep.small-ruminant lentiviruses (srlv), consisting of the caprine arthritis-encephalitis virus (caev) and the maedi-visna virus (mvv), cause chronic multisystemic infections in goats and sheep. the srlv subtype b1, characterized by the prototypic strain caev-co, has a worldwide distribution and, remarkably, has been isolated exclusively from goats, suggesting potential host specificity. to test this hypothesis, srlv pol sequences were obtained by pcr amplification from blood samples of seropositive ...200516005486
first partial characterisation of small ruminant lentiviruses from greece.small ruminant lentivirus (srlv) infections are widespread in greece, but srlvs have never been isolated and characterized. in this study, we present the sequence of a 574-nucleotide (191-amino acid) region of the gag gene of srlv strains from four sheep and one goat from a single geographic area of greece. all five sequences appeared to be closely related at both nucleotide (2.1-14.2% variation) and deduced amino acid (1.6-4.2% variation) level. greek srlv strains were closer to ovine prototypi ...200515964721
risk factors for the infection of swiss goat herds with small ruminant lentivirus: a case-control the mid-1980s, switzerland started a programme to eradicate caprine arthritis-encephalitis - an infectious disease of goats caused by the small ruminant lentivirus (srlv). since 1996, progress towards eradication has slowed down, owing to infections occurring on farms from which the infection had previously been eliminated. to investigate specific risk factors for these new infections and to improve the eradication programme, a case-control study was conducted. cases consisted of farms that h ...200516113168
antibody response in sheep experimentally infected with different small ruminant lentivirus genotypes.two groups of sheep were experimentally infected by intratracheal route with two small ruminant lentivirus (srlv) isolates belonging to different genotypes (it-561 genotype a3 and it-pi1 genotype b2). seroconversion was evaluated using recombinant homologous and heterologous matrix protein/capsid antigen fusion protein. results clearly indicate that seroconversion against homologous antigen was detected well in advance as regards heterologous antigen in both groups, although the advantage of usi ...200616698088
application of pcr technique in diagnosis of small ruminant lentivirus infection in sheep and goats.detection of small ruminant lentiviruses (srlvs) in sheep and goats usually relies on serological testing. in this study, we evaluated semi-nested pcr and nested pcr techniques applied as a diagnostic tool for detection of maedi-visna virus (mvv) and caprine arthritis-encephalitis virus (caev) in naturally infected sheep and goats, respectively. the examination of 193 ovine and 85 caprine serum samples by the elisa revealed the presence of specific antibodies in 133 (69%) and 18 (21.2%) animals, ...200617203738
distribution and heterogeneity of small ruminant lentivirus envelope subtypes in naturally infected french sheep.small ruminants lentiviruses (srlv) nucleotide sequences spanning the v1v2 variable regions of the env gene were amplified by nested-pcr from 38 blood samples collected from 16 naturally infected sheep flocks in france. for the rapid srlv group determination of field isolates, the pcr-amplified fragments were subjected to a srlv-adapted heteroduplex mobility assay (hma). all viral sequences were clearly assignable to the srlv group b by hma analysis. twenty-seven srlv isolates were selected for ...200616616391
a novel deletion in the ltr region of a greek small ruminant lentivirus may be associated with low pathogenicity.greek small ruminant lentivirus (srlv) strains remain relatively uncharacterized at the molecular level, despite the fact that lentiviral diseases of small ruminants are known to be widespread in the country. in the present study, we investigated the sequence diversity of the ltr region in greek srlv strains from sheep with and without disease symptoms, since sequence differences within this genomic area have been shown to lead to srlvs with distinct replication rates. the ap-4 and aml (vis) mot ...200616446005
genetic characterization of small ruminant lentivirus in italian mixed flocks: evidence for a novel genotype circulating in a local goat this study, characterization of the gag gene of small ruminant lentiviruses was carried out in italian mixed flocks. the nearly complete gag gene was amplified and sequenced. within genotype a, subtype a1 and a novel subtype, a8, were found in goats, and another novel subtype, a9, was found in both sheep and goats. subtype b1 was found in both host species and subtype b2 was identified only in sheep. a novel, highly divergent sequence was obtained from goats in two epidemiologically related f ...200718024912
natural transmission and comparative analysis of small ruminant lentiviruses in the norwegian sheep and goat populations.serological surveys for small ruminant lentivirus (srlv) infections have revealed seropositive sheep in several mixed herds, where sheep are kept together with seropositive goats. here we have examined the genetic relationships in ltr, pol and env surface unit (su) and the growth patterns in goat (gsm) and sheep (fos) synovial membrane cell cultures of srlv isolates obtained from both mixed and single species herds. phylogenetic analyses of pol and env su revealed that norwegian srlvs derived fr ...200717240470
association of cd80 and cd86 expression levels with disease status of visna/maedi virus infected small ruminant lentivirus infections, cellular immune responses are diminished in clinically affected animals. the underlying mechanisms for this are unknown. in this study, we tested the hypothesis that alterations in expression of the co-stimulatory molecules b7-1 and b7-2 are involved in infections with visna/maedi virus (vmv), the prototype lentivirus of sheep. we studied b7 expression levels ex vivo in peripheral blood mononuclear cells (pbmcs), determining b7 rna levels by real time rev ...200718158734
small ruminant lentivirus proviral sequences from wild ibexes in contact with domestic goats.small ruminant lentiviruses (srlv) are widespread amongst domesticated goats and sheep worldwide, but have not been clearly identified in wild small ruminants, where they might constitute an animal health risk through contamination from local domesticates. srlv proviruses from three ibexes from the french alps are described and sequences from their gag gene and long terminal repeats (ltrs) were compared with sequences from local goats and goat/ibex hybrids. the ibex and hybrid proviruses formed ...200818474564
experimental infection of sheep with visna/maedi virus via the conjunctival space.experiments were performed to determine whether visna/maedi virus (vmv), a small ruminant lentivirus (srlv), could infect sheep via ocular tissues. the ev1 strain of vmv was administered into the conjunctival space of uninfected sheep, and the animals monitored for the presence of provirus dna and anti-vmv antibodies in blood. the results showed that provirus dna appeared in peripheral blood mononuclear cells of all animals within a few weeks of receiving either 10(6) tcid50 or 10(3) tcid50 of v ...200818474547
small-ruminant lentivirus enhances prpsc accumulation in cultured sheep microglial cells.sheep scrapie is the prototypical transmissible spongiform encephalopathy (prion disease), which has a fundamental pathogenesis involving conversion of normal cellular prion protein (prp(c) [c superscript stands for cellular]) to disease-associated prion protein (prp(sc) [sc superscript stands for sheep scrapie]). sheep microglial cell cultures, derived from a prnp 136vv/171qq near-term fetal brain, were developed to study sheep scrapie in the natural host and to investigate potential cofactors ...200818684809
characterization of an immunodominant epitope of small ruminant lentivirus (srlv) extend and complete the epitope mapping of gag-encoded structural proteins, the immunodiagnostic potential of nucleoprotein (np) of two different small ruminant lentivirus (srlv) genotypes were antigenically characterized. respective recombinant counterparts were generated and used in an enzyme-linked immunosorbent assay (elisa) format to test a panel of sera from infected flocks. results clearly indicate that a single linear epitope located within the c-terminal is partially cross-reactive a ...200818584880
seroprevalence, clinical incidence, and molecular and epidemiological characterisation of small ruminant lentivirus in the indigenous passirian goat in northern italy.eight dairy flocks, comprising a total of 323 indigenous passirian goats from northern italy, were examined to determine the seroprevalence and clinical incidence of small ruminant lentivirus (srlv) infections and to identify the srlv subtypes. the seroprevalence was 81.5% (55-95%). the clinical incidence was 2.5% (0-8.3%) and was apparently low due to the practice of culling clinically affected animals. phylogenetic analysis of eight pcr fragments (one sample from each flock) revealed that all ...200818584116
serological characterization of the new genotype e of small ruminant lentivirus in roccaverano goat flocks.maedi visna virus (mvv) and caprine arthritis encephalitis virus (caev) are a heterogeneous group of infectious agents affecting sheep and goats. due to their natural cross-species infection they are referred to as small-ruminant lentiviruses (srlv). recently a new genetic cluster, highly divergent from mvv and caev was identified in the north-west part of italy. a panel of genotype e specific antigens was developed and evaluated in flocks infected with b1 and e strains. the results clearly indi ...200919629741
impact of natural sheep-goat transmission on detection and control of small ruminant lentivirus group c infections.dissemination of small ruminant lentivirus (srlv) infections in norway is affected by the different control strategies used for maedi-visna virus (mvv) infections in sheep and caprine arthritis-encephalitis virus (caev) infections in goats. here we investigated srlv phylogenetic group variants in sheep. caev-like isolates, belonging to phylogenetic group c, were found among both seropositive sheep and goats in mixed flocks, in which sheep and goats are kept together. intra-herd clustering confir ...200918986775
antibody-based diagnosis of small ruminant lentivirus infection in seminal fluid.antibody-based diagnosis of small ruminant lentiviruses (srlvs) has been efficiently achieved using serum and milk, but not semen, for which polymerase chain reaction (pcr) has been proposed as a confirmatory technique. this work, involving 296 ovine (ovis aries) and caprine (capra hircus) semen donors, investigates whether seminal fluid (sf) can be reliably used in antibody-based srlv diagnosis. first, a gold standard was established to assess the infection status and determine the sensitivity ...200919729193
improvements in the detection of small ruminant lentivirus infection in the blood of sheep by pcr.the polymerase chain reaction on blood samples has been considered a complement to serological methods for the detection of small ruminant lentiviruses (srlv) infections in sheep and goats. this is a report on the results of a study to evaluate the use of the same blood sample for the detection of infected animals by elisa and pcr. a comparison between the results obtained by applying pcrs targeting ltr and gag sequences on blood clot, serum and peripheral blood leucocytes was made. in addition ...200919095008
small ruminant lentivirus tat protein induces apoptosis in caprine cells in vitro by the intrinsic pathway.the small ruminant lentiviruses, caprine arthritis-encephalitis virus (caev) and maedi visna virus (mvv) naturally cause inflammatory disease in goats and sheep, provoking chronic lesions in several different organs. we have previously demonstrated that in vitro infection of caprine cells by caev induces apoptosis through the intrinsic pathway (rea-boutrois, a., pontini, g., greenland, t., mehlen, p., chebloune, y., verdier, g. and legras-lachuer, c. 2008). in the present study, we used tat dele ...200919007964
small ruminant lentivirus genotype e is widespread in sarda goat.the highly divergent srlv genotype e has recently been characterized in italy as a low pathogenic caprine lentivirus in the roccaverano breed. the availability of a genotype specific diagnostic test based on a comparative assay, using a combination of genotype specific recombinant antigens allows a wide serosurvey in other goat populations. the island of sardinia still has the highest small ruminant population of any italian region and crossbreeding has been limited to goats, mainly with the mal ...201020060658
recombinant small ruminant lentivirus subtype b1 in goats and sheep of imported breeds in mexico.nucleotide sequences of small ruminant lentiviruses (srlvs) were determined in sheep and goats, including progeny of imported animals, on a farm in mexico. on the basis of gag-pol, pol, env and ltr sequences, srlvs were assigned to the b1 subgroup, which comprises caprine arthritis-encephalitis virus (caev)-like prototype sequences mainly from goats. in comparison with caev-like env sequences of american and french origin, two putative recombination events were identified within the v3-v4 and v4 ...201020932787
diagnostic assays used to control small ruminant lentiviruses.the serologic diagnostic tests, such as the agar gel immunodiffusion assay and various types of enzyme-linked immunosorbent assays (elisas), have contributed to the reduction of small ruminant lentivirus (srlv) infections worldwide. because there are no treatments or efficacious vaccines, the serologic diagnostic tests have supported most of the eradication efforts by testing and removal or separation of adult animals that generate antibodies to srlvs. with the advent of molecular diagnostics, s ...201021088167
elimination of small ruminant lentivirus infection from sheep flocks and goat herds aided by health schemes in great britain.over a period of 11 years, 33 sheep or goat holdings lost their maedi-visna or caprine arthritis-encephalitis accredited status (mean 2.8 per year [0.09 per cent] of the accredited holdings in great britain). of these, 22 sheep flocks and two goat herds eradicated the infection and regained their accredited status. in addition, 10 sheep flocks and two goat herds managed to eradicate infection, having joined the scheme with infected animals. in flocks and herds with a high initial prevalence of i ...201021257509
use of small ruminant lentivirus-infected rams for artificial insemination.the presence of proviral dna, mrna transcripts and/or viral proteins in small ruminant lentiviral infections may be intermittent. the aim of this study was to identify methods of avoiding small ruminant lentivirus (srlv) transmission to ewes when using infected rams in artificial insemination (ai). semen from rams, seropositive and pcr-positive in blood but consistently negative for both proviral dna and viral protein expression in semen, was used to artificially inseminate 19 ewes. follow-up in ...201020692857
use of serology and polymerase chain reaction for the rapid eradication of small ruminant lentivirus infections from a sheep flock: a case report.a srlv-free sheep flock incurred infection which led to an srlv infection rate of over 50% of the ewes (34/64) within a 30 months period, indicating that environmental conditions were favourable to transmission. an intensive regimen of sampling at short intervals and testing for srlv antibodies and proviral dna combined with strict management was implemented for the entire flock, lambs and yearlings included. this resulted in eradication of the infection within two testing and culling rounds wit ...201019500811
visna/maedi virus genetic characterization and serological diagnosis of infection in sheep from a neurological extensive outbreak characterized by the appearance of neurological symptoms in small ruminant lentivirus (srlv) infected sheep has been identified in spain, but the genetic characteristics of the strain involved and differential diagnostic tools for this outbreak remain unexplored. in this work, 23 visna-affected naturally infected animals from the outbreak, 11 arthritic animals (both groups presenting anti-visna/maedi virus serum antibodies), and 100 seronegative animals were used. eight of ...201121940116
Genetic and antigenic characterization of small ruminant lentiviruses circulating in Poland.Small ruminant lentivirus (SRLV) infections are widespread in Poland, but the genetic features of sheep viruses are still lacking and limited to partial gag sequences for goat viruses. In this study, segments from the gag and env genes of Polish SRLV strains screened by heteroduplex mobility assay were subjected to genetic analyses. Subtype A1 was found in both sheep and goats, while subtypes B1 and B2 were found in goats and sheep, respectively. In addition, two novel subtypes (named A12 and A1 ...201122155513
Phylogenetic analysis of small ruminant lentivirus (SRLV) in Italian flocks reveals the existence of novel genetic subtypes.In order to investigate the genetic heterogeneity of small ruminant lentivirus (SRLV) isolates in Italy, 55 clinical samples collected between 1998 and 2010 were analysed. The phylogenetic study was based on analysis of gag-pol sequences. Our findings revealed that the SRLVs belonged to the subtype A9 (n = 3, sheep), B1 (n = 5, goat), B2 (n = 3, sheep) and E2 (n = 5, goat). Interestingly, 39 isolates from both sheep and goat, significantly differed from all the other SRLVs previously described a ...201121858464
characterization of new small ruminant lentivirus subtype b3 suggests animal trade within the mediterranean basin.small ruminant lentiviruses (srlv) represent a group of viruses infecting sheep and goats worldwide. despite the high heterogeneity of genotype a strains which cluster into as many as 10 subtypes, the genotype b was believed to be less complex and has so far been subdivided into only 2 subtypes. here we describe two novel full-length proviral sequences isolated from sarda sheep in two italian regions. genome sequence as well as the main linear epitopes clearly grouped this cluster into b genotyp ...201121562119
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