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1.
Theriogenology ; 86(8): 1953-1957.e1, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27461580

RESUMO

The transmission frequency of small ruminant lentiviruses (SRLVs) through the placenta is controversial and may be associated with breed susceptibility. In Mexico, SRLV infections in sheep have been poorly studied. This work explores the presence of antibodies and proviral DNA in Mexican Pelibuey sheep. Enzyme-linked immunosorbent assays (ELISAs; three commercial kits and two on the basis of synthetic peptides) and polymerase chain reaction (PCR; amplifying the long terminal repeat and gag segments) were performed to diagnose SRLV infection in 25 adult Pelibuey ewes with an average age of 2.5 years and 32 fetuses with gestational ages ranging from 40 to 90 days without clinical signs of SRLV. Two of the three commercial ELISAs and the synthetic peptide-based ones were positive for SRLV antibody detection in 28% and 24% of the ewes, respectively, whereas none of the fetuses were positive by any of the ELISAs. By PCR, 31% of the ewes and, interestingly, two fetuses were positive. Characteristic SRLV lesions were not found in the fetal and/or ewe tissues, including those with positive PCR results. These findings demonstrate the susceptibility of Pelibuey sheep to SRLV infection and the low transmission frequency through the placenta.


Assuntos
Infecções por Lentivirus/veterinária , Lentivirus Ovinos-Caprinos/isolamento & purificação , Doenças dos Ovinos/virologia , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Infecções por Lentivirus/epidemiologia , Infecções por Lentivirus/virologia , Lentivirus Ovinos-Caprinos/classificação , México/epidemiologia , Ovinos , Doenças dos Ovinos/epidemiologia
2.
Virology ; 475: 159-71, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25462356

RESUMO

The molecular epidemiology of small ruminant lentiviruses (SRLVs) is constantly changing due to animal movements, cross species transmission and because of their rapid evolutionary rate. This study reports a comprehensive genetic and phylogenetic analysis based on consensus gag and pol sequences covering 3kb of the SRLV genome from small ruminants in Québec, Canada. A group of strains obtained from goats originating from different flocks, segregated in a unique clade distinct from currently known SRLV groups. Genetic dissection of the gag gene from these strains revealed that it originated as a result of a recombination event between parental strains currently circulating in small ruminants of the country. Following HIV nomenclature, we propose to call this group of strains, circulating recombinant form 1 SRLV, or CRF01_AB SRLV. In addition, the study confirms the existence of genetically distinct and homogeneous populations of SRLVs infecting sheep and goats housed in single species flocks.


Assuntos
Doenças das Cabras/virologia , Infecções por Lentivirus/veterinária , Lentivirus Ovinos-Caprinos/genética , Lentivirus Ovinos-Caprinos/isolamento & purificação , Doenças dos Ovinos/virologia , Sequência de Aminoácidos , Animais , DNA Viral/genética , Proteínas de Fusão gag-pol/química , Proteínas de Fusão gag-pol/genética , Variação Genética , Doenças das Cabras/epidemiologia , Cabras , Infecções por Lentivirus/epidemiologia , Infecções por Lentivirus/virologia , Lentivirus Ovinos-Caprinos/classificação , Dados de Sequência Molecular , Filogenia , Quebeque/epidemiologia , Alinhamento de Sequência , Testes Sorológicos , Ovinos , Doenças dos Ovinos/epidemiologia
3.
Vet Microbiol ; 162(2-4): 572-581, 2013 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-23206411

RESUMO

Three field isolates of small ruminant lentiviruses (SRLVs) were derived from a mixed flock of goats and sheep certified for many years as free of caprine arthritis encephalitis virus (CAEV). The phylogenetic analysis of pol sequences permitted to classify these isolates as A4 subtype. None of the animals showed clinical signs of SRLV infection, confirming previous observations which had suggested that this particular subtype is highly attenuated, at least for goats. A quantitative real time PCR strategy based on primers and probes derived from a highly variable env region permitted us to classify the animals as uninfected, singly or doubly infected. The performance of different serological tools based on this classification revealed their profound inadequacy in monitoring animals infected with this particular SRLV subtype. In vitro, the isolates showed differences in their cytopathicity and a tendency to replicate more efficiently in goat than sheep cells, especially in goat macrophages. By contrast, in vivo, these viruses reached significantly higher viral loads in sheep than in goats. Both env subtypes infected goats and sheep with equal efficiency. One of these, however, reached significantly higher viral loads in both species. In conclusion, we characterized three isolates of the SRLV subtype A4 that efficiently circulate in a mixed herd of goats and sheep in spite of their apparent attenuation and a strict physical separation between goats and sheep. The poor performance of the serological tools applied indicates that, to support an SRLV eradication campaign, it is imperative to develop novel, subtype specific tools.


Assuntos
Doenças das Cabras/virologia , Infecções por Lentivirus/veterinária , Lentivirus Ovinos-Caprinos/classificação , Doenças dos Ovinos/virologia , Animais , Vírus da Artrite-Encefalite Caprina/classificação , Vírus da Artrite-Encefalite Caprina/genética , Vírus da Artrite-Encefalite Caprina/isolamento & purificação , Sequência de Bases , Genes env , Genes pol , Doenças das Cabras/sangue , Cabras , Infecções por Lentivirus/virologia , Lentivirus Ovinos-Caprinos/genética , Lentivirus Ovinos-Caprinos/isolamento & purificação , Leucócitos Mononucleares/virologia , Filogenia , Ovinos , Doenças dos Ovinos/sangue , Carneiro Doméstico , Vírus Visna-Maedi/classificação , Vírus Visna-Maedi/genética , Vírus Visna-Maedi/isolamento & purificação
4.
Vet Microbiol ; 144(1-2): 24-31, 2010 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-20060658

RESUMO

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 Maltese breed. A serological survey was carried out on sheep flocks and goat herds, using individual sera as well as a bulk milk-adapted procedure. Genotype E was identified in more than 50% of goat herds and none of the sheep flocks thus supporting the idea that this genotype is specifically associated with the goat species. The full-length proviral sequence of a Sardinian isolate revealed and confirmed the deletion of dUTPase subunit and the absence of both vpr gene and the 71bp repeat of the LTR. Genetic similarity of this isolate with the prototype strain Roccaverano was not more than 84%, supporting the designation of two subtypes within genotype E. Nevertheless, in vitro properties of the Sardinian strain were different from those of the Roccaverano strain in terms of ability to infect synovial membrane and produce syncitia. Remarkable differences in the HV1 and HV2 of the env gene were recorded, with the Sardinian isolate displaying sequence motif more similar to arthritic strains. Data presented suggest diffusion of genotype E is wider than previously thought.


Assuntos
Doenças das Cabras/genética , Cabras/genética , Infecções por Lentivirus/veterinária , Lentivirus Ovinos-Caprinos/genética , Animais , Sequência de Bases , Primers do DNA , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Produtos do Gene gag/genética , Genes Virais , Genótipo , Doenças das Cabras/sangue , Doenças das Cabras/virologia , Cabras/virologia , Itália/epidemiologia , Infecções por Lentivirus/sangue , Infecções por Lentivirus/epidemiologia , Lentivirus Ovinos-Caprinos/classificação , Lentivirus Ovinos-Caprinos/isolamento & purificação , Leite/virologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Membrana Sinovial/virologia
5.
Vet Microbiol ; 138(1-2): 156-62, 2009 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-19339126

RESUMO

Small ruminant lentiviruses (SRLVs) cause different clinical forms of disease in sheep and goats. So far in Spain, Maedi visna virus-like (MVV-like) sequences have been found in both species, and the arthritic SRLV disease has never been found in sheep until a recent outbreak. Knowing that arthritis is common in goats, it was of interest to determine if the genetic type of the virus involved in the sheep arthritis outbreak was caprine arthritis encephalitis virus-like (CAEV-like) rather than MVV-like. Alignment and phylogenetic analyses on nucleotide and deduced amino acid sequences from SRLV of this outbreak, allowed a B2 genetic subgroup assignment of these SRLV, compatible with a correspondence between the virus genetic type and the disease form. Furthermore, an isolate was obtained from the arthritic outbreak, its full genome was CAEV-like but the pol integrase region was MVV-like. Although its LTR lacked a U3 repeat sequence and had a deletion in the R region, which has been proposed to reduce viral replication rate, its phenotype in sheep skin fibroblast cultures was rapid/high, thus it appeared to have adapted to sheep cells. This outbreak study represents the first report on CAEV-like genetic findings and complete genome analysis among Spanish small ruminants.


Assuntos
Artrite Infecciosa/veterinária , Surtos de Doenças/veterinária , Infecções por Lentivirus/veterinária , Lentivirus Ovinos-Caprinos/genética , Doenças dos Ovinos/virologia , Animais , Artrite Infecciosa/genética , Artrite Infecciosa/virologia , Sequência de Bases , Plexo Corióideo/virologia , Clonagem Molecular , DNA Viral/genética , DNA Viral/isolamento & purificação , Genoma Viral , Infecções por Lentivirus/epidemiologia , Lentivirus Ovinos-Caprinos/classificação , Lentivirus Ovinos-Caprinos/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase/métodos , RNA Viral/genética , Ovinos , Espanha , Líquido Sinovial/virologia , Membrana Sinovial/virologia , Sequências Repetidas Terminais/genética , Vírus Visna-Maedi/classificação , Vírus Visna-Maedi/genética , Vírus Visna-Maedi/isolamento & purificação
6.
Vet Microbiol ; 135(3-4): 231-8, 2009 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-18986775

RESUMO

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 confirmed that mixed flock animals were infected by the same virus variant, suggesting ongoing interspecies transmission. Few sheep flocks were found to be infected with the MVV-like phylogenetic group A. The apparent absence of SRLV group A type in goats is probably due to the MVV control programme and animal management practices. SRLV group C targets lungs and mammary glands in sheep, and induces typical SRLV pathological lesions. SRLV group C isolated from the sheep mammary glands suggested a productive infection and potential for transmission to offspring. SRLV group C was most prevalent among goats. A lower PCR sensitivity in seropositive sheep suggested a lower load of SRLV group C provirus in sheep than in goats. Higher genetic divergence of group C than in other SRLV groups and extensive heterogeneity among group C isolates in the matrix C-terminal region demonstrate the need for identifying conserved target regions when developing PCR protocols for SRLV detection. As sheep and goats may serve as reservoirs for all SRLV genogroup types, successful control programmes require inclusion of both species.


Assuntos
Doenças das Cabras/virologia , Infecções por Lentivirus/transmissão , Infecções por Lentivirus/veterinária , Lentivirus Ovinos-Caprinos/patogenicidade , Doenças dos Ovinos/virologia , Animais , Plexo Corióideo/virologia , DNA Viral/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Produtos do Gene gag/genética , Doenças das Cabras/sangue , Doenças das Cabras/transmissão , Cabras , Infecções por Lentivirus/sangue , Lentivirus Ovinos-Caprinos/classificação , Lentivirus Ovinos-Caprinos/genética , Leucócitos Mononucleares/virologia , Pulmão/virologia , Linfonodos/virologia , Mediastino/virologia , Filogenia , Reação em Cadeia da Polimerase , Ruminantes , Ovinos , Doenças dos Ovinos/sangue , Doenças dos Ovinos/transmissão , Membrana Sinovial/virologia , Vírus Visna-Maedi/classificação
7.
Virus Res ; 102(2): 215-20, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15084404

RESUMO

Seven new ovine progressive pneumonia virus (OPPV) field isolates were derived from colostrum and milk of 10 naturally OPPV-infected sheep from the US Sheep Experiment Station in Dubois, Idaho, USA. Sixteen sequences of the surface envelope glycoprotein (SU) from these seven Dubois OPPV field isolates and SU sequence from OPPV WLC1 were obtained, aligned with published SRLV SU sequences, and analyzed using phylogenetic analysis using parsimony (PAUP). Percent nucleotide identity in SU was greater than 95.8% among clones from individual Dubois OPPVs and ranged from 85.5 to 93.8% between different Dubois OPPV clones. SU sequences from Dubois OPPVs and WLC1 OPPV had significantly higher percent nucleotide identity to SU sequences from the North American OPPVs (85/34 and S93) than caprine-arthritis encephalitis virus (CAEVs) or MVVs. PAUP analysis also showed that SU sequences from the Dubois OPPVs and OPPV WLC1 grouped with other North American OPPVs (85/34 and S93) with a bootstrap value of 100 and formed one OPPV clade II group. In addition, Dubois and WLC1 SU amino acid sequences had significantly higher identity to SU sequences from North American OPPVs than CAEV or MVV. These data indicate that the seven new Dubois OPPV field isolates along with WLC1 OPPV are part of the OPPV clade II and are distinct from CAEVs and MVVs.


Assuntos
Glicoproteínas/genética , Infecções por Lentivirus/veterinária , Lentivirus Ovinos-Caprinos/classificação , Lentivirus Ovinos-Caprinos/genética , Doenças dos Ovinos/virologia , Proteínas do Envelope Viral/genética , Animais , Colostro/virologia , DNA Viral/química , DNA Viral/isolamento & purificação , Idaho , Infecções por Lentivirus/virologia , Lentivirus Ovinos-Caprinos/isolamento & purificação , Leite/virologia , Filogenia , Provírus/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Ovinos/virologia
8.
Virology ; 319(1): 12-26, 2004 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-14967484

RESUMO

We performed a phylogenetic analysis of caprine and ovine lentiviruses using long sequences in gag and pol of 104 new Swiss isolates and six available corresponding database sequences. Forty-five isolates, forming five sequence clusters, were unclassifiable by the present classification. Pairwise DNA distance analysis indicated different categories of relatedness, requiring a new classification system. We propose four principal sequence groups, A-D, which differ by 25-37%. Groups A and B are further divided into subtypes which differ by 15-27%. Group D and four of the seven group A subtypes, A3, A4, A5 and A7, are formed by new Swiss isolates. Molecular epidemiology revealed that Swiss B1 strains differed no more from French, Brazilian or US strains than from each other, suggesting virus propagation through international livestock trade. Furthermore, infection of goats by subtypes A3 or A4 was significantly associated with documented contact with sheep, which also harbor these subtypes, thus indicating regularly occurring sheep-to-goat transmission.


Assuntos
Doenças das Cabras/virologia , Infecções por Lentivirus/veterinária , Lentivirus Ovinos-Caprinos/classificação , Filogenia , Doenças dos Ovinos/virologia , Agricultura , Animais , Genes gag , Genes pol , Doenças das Cabras/transmissão , Cabras , Infecções por Lentivirus/epidemiologia , Infecções por Lentivirus/transmissão , Lentivirus Ovinos-Caprinos/genética , Lentivirus Ovinos-Caprinos/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Análise de Sequência , Ovinos , Doenças dos Ovinos/transmissão
9.
Virus Res ; 85(1): 29-39, 2002 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-11955636

RESUMO

Small ruminant lentiviruses (SRLV), i.e. caprine arthritis-encephalitis virus (CAEV) (which infects goats) and maedi-visna virus (MVV) (which infects sheep) are two closely related lentiviruses but the relationship between goat and sheep lentiviruses has not been clearly established. To better understand their genetic relationship, we reinvestigated the phylogeny of SRLV using new sequences from an Irish and a Norwegian strain together with sequences available from databases. The phylogenetic analyses were carried out on the gag, pol and env fragments using four methods: neighbor-joining (NJ), Fitch and Margoliash (Fitch), Fitch and Wagner parsimony (Pars) and maximum likelihood (ML). The tree topologies were consistent whether derived from any of the four methods or any of the gene fragments, but the phylogenetic analyses in the pol and env regions were more informative than in the gag region. The Tamura-Nei model with variable rates across sites (described by a gamma distribution) provides a more accurate description of SRLV evolution than simple methods. The newly described Irish lentivirus strain, which was isolated from a goat, was closely related to the lentivirus that infects sheep: MVV. The novel Norwegian CAEV strain belonged to a cluster specific to the CAEV strains from Norway. Together, both data confirm the previously reported subdivision of the different SRLV strains into six clades. The caprine and ovine lentivirus sequences are interspersed in phylogenetic trees, supporting the existence of cross-species transmission. Nevertheless, the transmission of an ovine lentivirus to a goat could trigger the emergence of some goat-adapted phylums. Our new sequences confirm the complex situation in SRLV phylogeny but more sequences are needed to elucidate more precisely the relationship between SRLV.


Assuntos
Lentivirus Ovinos-Caprinos/classificação , Animais , Genes env , Genes gag , Genes pol , Heterogeneidade Genética , Cabras/virologia , Irlanda , Lentivirus Ovinos-Caprinos/genética , Lentivirus Ovinos-Caprinos/isolamento & purificação , Filogenia
10.
Virology ; 238(1): 135-44, 1997 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-9375017

RESUMO

Ovine lentiviruses (OvLV) resemble human immunodeficiency viruses in genomic organization, viral heterogeneity, and spectrum of cytophenotypic expression. To gain a better understanding of the relationship of North American OvLV isolates with other characterized OvLV strains, the complete DNA nucleotide sequence of the env region of a highly lytic (rapid/high) OvLV strain (85/34) was determined and compared with the sequence of amplicons within env of three other OvLV strains of varying cytophenotype and isolated from the same flock of sheep. LTR and pol regions also were compared among these strains. The env region of 85/34 was 986 codons in length and the reported nucleotide sequence showed features shared by other OvLV including heavy glycosylation and conserved and hypervariable regions within the surface membrane protein region. Phylogenetic analyses of regions within LTR, reverse transcriptase, and env grouped the four virus strains together and similar to the maedi-visna OvLV strains, including visna virus, South African ovine maedi visna virus, and EV1 (British OvLV isolate), but they were distinct from caprine arthritis encephalitis virus.


Assuntos
Genes env , Lentivirus Ovinos-Caprinos/classificação , Lentivirus Ovinos-Caprinos/genética , Filogenia , Ovinos/virologia , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA , Evolução Molecular , Humanos , Lentivirus Ovinos-Caprinos/isolamento & purificação , Dados de Sequência Molecular , América do Norte , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Proteínas do Envelope Viral/química , Vírus Visna-Maedi/classificação , Vírus Visna-Maedi/genética , Vírus Visna-Maedi/isolamento & purificação
11.
Arch Virol ; 142(6): 1125-37, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9229003

RESUMO

We have recently shown that French small ruminant lentiviruses (SRLV) from sheep are more similar to Caprine Arthritis Encephalitis Virus (CAEV) than to visna maedi virus (VMV) in a conserved region of the pol gene. To extend these results, we have examined sequences from a variable region of the env gene in French SRLV. We found that they were nearly equally distant from both CAEV and VMV strains, suggesting a considerable divergence since the initial introduction of the virus. Analysis of separate clones from individual animals showed that some carry a population of variant viruses. The study of further pol gene sequences from both goats and sheep suggests that viral variants show little or no host species specificity. A phylogenetic tree of pol gene sequences confirmed the presence of a novel genotype of SRLV in France.


Assuntos
Lentivirus Ovinos-Caprinos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Viral , Genes env , Genes pol , Heterogeneidade Genética , Genoma Viral , Genótipo , Cabras , Lentivirus Ovinos-Caprinos/classificação , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Ruminantes/virologia , Homologia de Sequência de Aminoácidos , Ovinos
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