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serologic diagnosis of caprine arthritis-encephalitis by elisa with two recombinant proteins in a parallel testing format.a scheme for screening sera for antibodies to caprine arthritis-encephalitis virus (caev) was evaluated for its ability to identify positive and negative samples in a population with heterogeneous risk factors, using the criteria of sensitivity, specificity and positive predictive value. five hundred caprine serum samples were tested using a transmembrane recombinant-based elisa. those that gave positive results were considered positive, while those with equivocal or negative results were retest ...19958567987
changes in serum antioxidant concentrations during infection with caprine lentivirus.we are currently using caprine arthritis encephalitis virus (caev) infection in goats as a model to understand changes in some clinical parameters and host response to infection with human immunodeficiency virus (hiv). the objective of this study was to measure changes in serum antioxidant activities in various age groups of goats infected with caev. serum from caev-infected goats had significantly higher catalase activity (105.47 +/- 5.96 ku/l) than serum from healthy control goats (79.92 +/- 1 ...19958574149
prevalence, spread and control of caprine arthritis-encephalitis virus in dairy goat herds in new south wales.a study of the prevalence, spread and control of caprine arthritis-encephalitis virus (caev) in dairy goat herds in new south wales (nsw) during 1986-1988 found that 56.8% of 1484 goats in 14 dairy herds were infected with caev. the prevalence of caev infection within most herds not implementing control measures increased during the study. at the end of the study, 59.7% of 1322 goats were infected. the prevalence of caev increased with age. differences between breeds were less apparent. within s ...19958585848
[serologic investigations on the occurrence of maedi-visna antibodies in game ruminants].the lentiviruses of small domestic ruminants (maedi-visna and caprine arthritis-encephalitis virus) have been shown to be infective for each other. there are only few investigations of virus susceptibility of other species of animals. the aim of our study reported here was to evaluate sera of wild animal species for lentivirus antibodies. 344 sera of capreolus capreolus, cervus elaphus and dama dama from a territory with known sheep populations prevalence were tested in the agar gel immunodiffus ...19958593775
two species of rev proteins, with distinct n termini, are expressed by caprine arthritis encephalitis virus.several cdna clones representing alternatively spliced rev-specific transcripts were isolated from a cdna library prepared from himalayan tahr cells infected with caprine arthritis encephalitis virus (caev). we previously characterized two rev-like cdna species, d1 and d2, and a tat e1 cdna containing the rev coding sequence downstream to the tat. in these cdnas, the rev coding domain derives its amino terminus from the n terminus of env, which is spliced to the 3' open reading frame encoding th ...19968642706
a long term study of goats naturally infected with caprine arthritis-encephalitis virus.the caprine arthritis-encephalitis virus (caev) is a big problem in dairy goat industry. little is known about its characteristics in naturally infected goat herds. the aims of this study were: 1) to study how antibody expression, measured by agar gel immunodiffusion test (agidt), varied over time in naturally infected, seropositive goats, 2) to observe clinical signs in seropositive adult goats and 3) to follow seroconversion and gamma globulin concentration in goat kids artificially reared on ...19968659344
-pcr for the detection of lentiviruses from small ruminants-.the polymerase chain reaction has all attributes of a promising diagnostic technique. it is rapid, simple to perform and extremely sensitive. in a pcr developed for the detection of small ruminant lentiviruses (srlv), we found under ideal conditions a detection on sensitivity up to less than 10 template dna copies. the diagnostic application of pcr was not fully satisfying, even when the technique was refined by the use of a panel of suitable primer pairs. the reliability of pcr in blood and mil ...19968720734
restrictive type of replication of ovine/caprine lentiviruses in ovine fibroblast cell cultures.caprine arthritis-encephalitis virus (caev) is a natural lentivirus pathogen of goats. caev, like all members of the ovine/ caprine lentivirus family, has an in vivo tropism for cells of the monocyte/macrophage cell lineage and activation of viral gene expression is observed only following differentiation of monocytes to macrophages. in addition to cells of the monocyte/ macrophage lineage, caev and the closely related maedi visna virus of sheep (mvv) can also replicate productively in fibro-epi ...19968806484
variations in lentiviral gene expression in monocyte-derived macrophages from naturally infected sheep.seventy-nine 1-year-old lambs from three individual farms and a feedlot were examined for natural lentivirus infection. we used three different methods to detect infection and to identify the stage of the ovine lentivirus life cycle in blood-derived macrophages. cytopathic infectious virus was obtained from 14/14 border leicester animals obtained from a naturally infected flock. neither virus particles, virus proteins, virus specific antibodies nor viral dna were detected in samples from 34 lamb ...19968811001
requirement of caprine arthritis encephalitis virus vif gene for in vivo replication.replication of vif-caprine arthritis encephalitis virus (caev) is highly attenuated in primary goat synovial membrane cells and blood-derived macrophages compared to the wild-type (wt) virus. we investigated the requirement for caev vif for in vivo replication and pathogenicity in goats by intra-articular injection of either infectious proviral dna or viral supernatants. wild-type caev dna or virus inoculation induced persistent infection resulting in severe inflammatory arthritic lesions in the ...19968862419
replication in goats in vivo of caprine arthritis-encephalitis virus deleted in vif or tat genes: possible use of these deletion mutants as live vaccines. 19968882321
highly sensitive qualitative and quantitative detection of reverse transcriptase activity: optimization, validation, and comparative analysis with other detection systems.an ultra-sensitive assay for reverse transcriptase (rt) activity called amp-rt has been developed. an in vitro transcribed heteropolymeric rna sequence was used as a template, and polymerase chain reaction (pcr) amplification with southern-blot hybridization served as a detection system for the cdna product of the reaction. titration of mg2+ and mn2+ concentrations using the human immunodeficiency virus type 1 (hiv-1) and the human t lymphotropic virus type 1 (htlv-i), respectively, showed optim ...19968882946
detection of caprine arthritis--encephalitis virus rna in macrophages by in situ hybridization using fluorescein-labelled single-stranded rna probes.the use of in situ hybridization (ish) for the detection of caprine arthritis-encephalitis virus (caev) rna with fluorescein-11-utp-labelled single-stranded rna probes is described. three different probes were made by pcr amplification of proviral caev dna (strain 75-g63). the pcr products were cloned into the plasmid pam-18, and labelled single-stranded rna probes were synthesized by the use of rna polymerase. the ltr probe was able to detect viral rna in caev-infected, cultured caprine macroph ...19968914248
genetic characterization of two phenotypically distinct north american ovine lentiviruses and their possible origin from caprine arthritis-encephalitis virus.ovine and caprine lentiviruses are closely related genetically and antigenically although the diseases that these viruses cause in their respective host animals can vary greatly. in sheep, syndromes consist primarily of interstitial pneumonia with rare occurrences of arthritis and encephalitis, whereas in goats, the disease expresses mainly as arthritis in adult animals with rare cases of encephalitis in newborns. experimentally, viruses from either sheep or goats can infect animals of the recip ...19968918528
retroviruses and systemic lupus erythematosus.in some animal models of autoimmune diseases the roles of exogenous and endogenous retroviruses are clearly defined. in ungulates caprine arthritis encephalitis virus, equine infectious anemia virus or maedi-visna virus infections cause a well-defined autoimmune disease and the appearance of seropositivity of the animals is of diagnostic value. likewise, in mrl lpr/lpr mice insertion of a retrotransposon into the fas gene could clearly be shown to cause survival of autoreactive lymphocytes. desp ...19968930671
definition of the rre binding and activation domains of the caprine arthritis encephalitis virus rev protein.caprine arthritis encephalitis virus (caev) is a lentivirus which is closely related by nucleotide sequence and biological properties to visna virus and is more distantly related to the human aids virus, hiv-1. previous studies indicated that the caev rev protein (rev-c) functions as a trans-activator of mrna cytoplasmic transport and expression. the function of rev-c is mediated through an rna element (rre-c) present between nucleotides (nt) 7906 and 8110 in the caev env gene. in this study, rn ...19968941328
stat1 pathway is involved in activation of caprine arthritis-encephalitis virus long terminal repeat in monocytes.the caprine arthritis-encephalitis virus (caev) long terminal repeat (ltr) is activated by gamma interferon (ifn-gamma) in promonocytic cells. we have previously shown that a 70-bp element is necessary and sufficient for the response of the caev ltr to this cytokine. at the 5' end, this 70-bp ifn-gamma response element contains sequence similarity to the gamma activated site (gas). here we demonstrate that the putative gas element in the caev ltr binds specifically to a cellular factor induced b ...19978985415
expression of tnf alpha in arthritis caused by caprine arthritis encephalitis virus.goats infected with caprine arthritis encephalitis virus (caev) develop chronic arthritis sharing many features with human rheumatoid arthritis (ra). tnf is thought to be a key mediator contributing to the formation of the arthritic lesion in ra. we studied this cytokine in goats suffering from chronic arthritis. tnf alpha expressing cells were detected by in situ hybridization in synovial membranes of arthritic carpal joints. expression of tnf alpha did not correlate with the degree of viral re ...19968988874
the response of goat brain cells to infection by caprine arthritis-encephalitis virus.caprine arthritis-encephalitis virus is a lentivirus of goats causing encephalomyelopathy acutely in young goats and occasionally in late stages of chronically infected adult goats. to determine the specific brain cells infected by the virus and the response of other cell types, goat cerebrum explant cultures prepared from newborn goat kids were infected by virus application. infection of brain cultures was also possible by coculture with virus-infected macrophages. predominantly, microglia cell ...19968997523
comparative studies of bacterially expressed integrase proteins of caprine arthritis-encephalitis virus, maedi-visna virus and human immunodeficiency virus type 1.integrase (in) proteins mediate an essential step in retroviral life cycles, the integration of reverse-transcribed viral dna into the host genome. to create tools for direct comparative investigations, hexahistidine-tagged in proteins of the phylogenetically related lentiviruses caprine arthritis-encephalitis virus (caev), maedi-visna virus (mvv) and human immunodeficiency virus type 1 (hiv-1) were expressed in escherichia coli. after purification by affinity chromatography, the active enzymes ...19959049371
laboratory diagnostic tests for retrovirus infections of small ruminants.the most practical and reliable approach to confirming a diagnosis of oppv or caev infection is a combination of serology and clinical evaluation. although serology represents the most cost effective method of diagnosing persistently infected, clinically normal animals, testing errors occur; the frequency of error depends on the performance data of the particular serologic assay being used. when pcr detection of oppv and caev becomes routinely available, this detection method can be used in rigo ...19979071743
risk factors for transmission and methods for control of caprine arthritis-encephalitis virus infection.the major route of transmission of caprine-encephalitis virus (caev) is through the ingestion of caev-infected colostrum or milk. less efficient routes of transmission are associated with prolonged contact with infected goats and are reviewed in this article. prevention of caev is based on the removal of kids from their dam at birth, and feeding the kids heat-treated colostrum and pasteurized milk until weaning. serologic testing and segregation or culling of seropositive goats is necessary to m ...19979071745
hiv and human endogenous retroviruses: an hypothesis with therapeutic implications.the enzyme dutp pyrophosphatase (dutpase, ec 3.6.1.23) is essential for cellular dna replication and cell viability by virtue of its role in reducing the availability of dutp as a substrate for dna polymerases. several members of the onco- and lentivirus families of retroviruses encode dutpases and mutant strains of these viruses defective in this enzyme exhibit suboptimal replication kinetics. among the lentiviruses there exists a surprising phylogenetic discontinuity in the distribution of dut ...19969104494
rt-pcr detection of lentiviruses in milk or mammary secretions of sheep or goats from infected flocks.in this study we evaluated a reverse transcriptase polymerase chain reaction (rt-pcr) technique for detecting lentiviral infection in milk or mammary secretions from small ruminants. initial observations on seven goats infected with cloned caprine arthritis-encephalitis virus (caev) showed that rt-pcr on milk cells is as reliable as coculture for detecting viral infection, and is quicker and simpler. with a suitable choice of redundant primers followed by a semi-nested amplification, it proved p ...19979112733
productive replication of caprine arthritis-encephalitis virus is associated with induction of apoptosis.caprine arthritis-encephalitis virus (caev), an ungulate lentivirus, causes a natural infection in goats. the present report demonstrates that in vitro, caev infection is associated with apoptosis, characterized by morphological changes such as condensation of chromatin and the appearance of apoptotic bodies. the presence of dna fragments was documented by the appearance of a dna 'ladder' in agarose gel electrophoresis, as well as by in situ end-labelling of dna ends. in addition, flow cytometri ...19979129652
dutpase-minus caprine arthritis-encephalitis virus is attenuated for pathogenesis and accumulates g-to-a substitutions.the importance of the virally encoded dutpase for caev replication, invasiveness, pathogenesis, and genetic stability was investigated in goats infected by viruses with single point (du-g) and deletion (du-1) mutations of the dutpase gene (du gene). the du gene was found to be dispensable for caev replication in vivo as judged by times taken to seroconvert, frequencies of viral isolation, and tissue distribution of viral rnas. du- reversion at week 34 in one of three goats infected with the sing ...19979151845
caprine arthritis-encephalitis virus: detection of proviral dna in lactoserum cells. 19979160533
immunohistochemical identification of caprine arthritis-encephalitis virus in paraffin-embedded specimens from naturally infected goats.the expression of caprine arthritis-encephalitis virus capsid protein was studied in seropositive naturally infected asymptomatic goals (10< seropositive naturally infected encephalitic kids (12) and goats (4), and noninfected control goats (3). rabbit antiserum to recombinant viral capsid and matrix proteins were used in a biotin-streptavidin-alkaline phosphatase complex immunohistochemical method on sections of formalin- and ethanol-fixed tissue specimens. macrophages in inflamed areas of the ...19979163873
looking for leads in hiv's battle with immune system. 19979182329
immortalization of caprine fibroblasts permissive for replication of small ruminant lentiviruses.to establish immortalized caprine fibroblastic cell lines permissive for replication of small ruminant lentiviruses.19979185961
evaluation of selected antibiotic residue screening tests for milk from individual goats.because somatic cell counts (scc) of caprine milk are higher than scc of bovine milk, the performance of antibiotic residue tests for screening bovine milk was investigated for caprine milk. eighty-five does that were free of antibiotic usage for at least 30 d and that were free of clinical mastitis were sampled at three milkings during a 37-d period. at each sampling, foremilk was collected for bacteriological analysis, and composite bucket milk samples were collected for antibiotic testing and ...19979201581
immune responses in goats to caprine arthritis-encephalitis virus.in this study, goats were experimentally infected with caprine arthritis-encephalitis virus (caev). anti-caev antibodies were detected in vivo using indirect enzyme-linked immunosorbent assay (elisa) and western blot assays. the results showed that the sensitivity of detection of anti-caev antibodies using indirect elisa was relatively high, whereas western blotting was very sensitive for detection of p28 anti-caev antibody as 4 days postinfection. apparently, because of high immunogenicity of p ...19979210285
changes in the leukocyte phenotype profile of goats infected with the caprine arthritis encephalitis virus.the proportions of different sub-populations of leukocytes in five healthy goats and five goats infected with the caprine arthritis encephalitis virus (caev) were examined using immunofluorescence and flow cytometry. a panel of monoclonal antibodies that identified a monocytegranulocyte marker (gmi); the cd4, cd8, igm, mhc class i, mhc class ii and t19 antigens, and the gamma delta (gamma delta) t cell receptor was used. we observed a significant (p = 0.016) reduction in the proportion of monocy ...19979220584
type 1 and type 2 cytokine gene expression by viral gp135 surface protein-activated t lymphocytes in caprine arthritis-encephalitis lentivirus infection.peripheral blood mononuclear cells (pbmc) from saanen goats experimentally infected with the lentivirus caprine arthritis-encephalitis virus (caev) were evaluated by semiquantitative reverse transcriptase pcr for gamma interferon (ifn-gamma), interleukin-4 (il-4), and il-2 gene expression following in vitro stimulation with purified caev gp135 surface protein (su). studies examined three goats with chronic arthritis and four clinically asymptomatic goats at 5 years postinfection. su-responsive i ...19979223529
genomic heterogeneity of small ruminant lentiviruses: existence of heterogeneous populations in sheep and of the same lentiviral genotypes in sheep and goats.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 sepa ...19979229003
t-lymphocyte populations in the blood of caprine arthritis encephalitis virus-infected goats.the effect of natural infection by caprine arthritis encephalitis virus on the phenotypic pattern of t lymphocytes in peripheral blood was studied in a herd of 127 milking goats by flow cytometry. total leukocyte and t-lymphocyte numbers tend to decrease with age, with only small changes in the cd4/cd8 ratio. the lymphocyte phenotypes show no strong correlation with seropositivity to caev or the presence of clinical symptoms, suggesting that this macrophagetropic lentivirus does not greatly effe ...19979239842
caev infection does not affect prevalence of bacterial mastitis in goats. 19979257456
caprine arthritis encephalitis virus dysregulates the expression of cytokines in macrophages.caprine arthritis encephalitis virus (caev) is a lentivirus of goats that leads to chronic mononuclear infiltration of various tissues, in particular, the radiocarpal joints. cells of the monocyte/macrophage lineage are the major host cells of caev in vivo. we have shown that infection of cultured goat macrophages with caev results in an alteration of cytokine expression in vitro. constitutive expression of interleukin 8 (il-8) and monocyte chemoattractant protein 1 (mcp-1) was increased in infe ...19979311828
expression of cytokine mrna in lentivirus-induced arthritis.infection of goats with the lentivirus caprine arthritis encephalitis virus (caev) leads to persistent infection and development of chronic arthritis. we analyzed the expression of cytokines and viral rna in the joints of goats at early time points after experimental infection with caev and in those of animals suffering from chronic arthritis as a result of natural infection. in situ hybridization experiments showed that the pattern of cytokine expression in caprine arthritis was similar to that ...19979327739
north american and french caprine arthritis-encephalitis viruses emerge from ovine maedi-visna viruses.the full extent of genetic diversity among small ruminant lentiviruses (srlvs), i.e., caprine arthritis encephalitis viruses (caevs) and maedi-visna viruses (mvvs), remains unknown. this is due in part to the fact that few sequences of caev are available. to contribute to this knowledge, gag, pol, and env nucleotide sequences from an srlv named ca680 originating from a goat from western france were determined. this analysis revealed that this virus is closely related to the cork and 63 caev amer ...19979356342
effects of infection by caprine arthritis-encephalitis virus on milk production of goats.the effects of caprine arthritis-encephalitis virus on lactational performance of goats were examined. the results of an elisa for antibodies against caprine arthritis-encephalitis virus were compared with milk production records. mean production of milk, protein, fat, and lactose and somatic cell counts were compared for seropositive and seronegative goats of similar ages. the results from 1799 lactating goats from 66 herds suggested that milk production was similar for 1-yr-old goats that test ...19979361211
envelope glycoprotein nucleotide sequence and genetic characterization of north american ovine lentiviruses.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 cytophen ...19979375017
cytokine production in vitro by macrophages of goats with caprine arthritis-encephalitis.the response of caprine macrophages to exposure to caprine arthritis-encephalitis virus (caev) and lipopolysaccharide (lps) was investigated in female nubian and nubian crossbreed of goats. macrophages were matured in vitro from monocytes isolated from blood of control and caev-infected goats and the concentrations of tumor necrosis factor (tnf-alpha) and interleukin-6 (il-6) in culture supernatant after exposure of cells to lps and virus were assayed. though barely detectable in unstimulated ce ...19979449535
immunohistology of the early course of lentivirus-induced arthritis.caprine arthritis encephalitis (cae) is a lentiviral infection of goats characterized by mononuclear cell infiltration of various tissues, most prominently the joints, mammary glands and, in young animals, the brain. we have investigated the early stages of arthritis induced by intracarpal and intravenous infection with molecularly cloned cae virus. analysis of the synovial membranes by immunohistological methods showed that the proportion of cd8+ t cells peaked around day 12 post-infection. cd4 ...19989486408
caprine arthritis-encephalitis in an indigenous spanish breed of dairy goat.the presence of caprine arthritis and encephalitis (cae) in spain has never been officially acknowledged but it is suspected. goats have been imported from other european countries with a high prevalence of the disease, mainly france, and they might have introduced the disease into the indigenous goat population. a serological survey of caprine arthritis and encephalitis virus antibodies was carried out in 22 volunteer dairy murciano-granadina goat herds; 2513 lactating goats were tested with an ...19989507648
cloning and expression of caprine interferon-gamma.caprine interferon-gamma (ifn-gamma) cdna was cloned from mitogen stimulated peripheral blood mononuclear cell (pbmc) rna utilizing the reverse transcription-polymerase chain reaction (rt-pcr). the cdna open reading frame (orf) is 498bp, encoding a putative 166 amino acid (aa) protein (19327da). the predicted aa sequence homology of caprine ifn-gamma and the corresponding ovine, bovine and cervine cytokine is 98.8%, 95.2% and 92.8%, respectively. ifn-gamma cdna was subcloned and expressed in two ...19989524237
antibody reactivity to the transmembrane protein of the caprine arthritis encephalitis virus correlates with severity of arthritis: no evidence for the involvement of epitope mimicry.serum and synovial antibody reactivities of caprine arthritis encephalitis virus (caev) infected goats were assessed by western blotting against purified caev antigen and the greatest intensity of reactivity in the serum of arthritic goats was to the gp45 transmembrane protein (tm). the extracytoplasmic domain of the tm gene was cloned into a pgex vector and expressed in escherichia coli as a glutathione s transferase fusion protein (gst-tm). this clone was found to be 90.5 and 89.2% homologous ...19979533272
control of caprine arthritis-encephalitis virus and corynebacterium pseudotuberculosis infection in a norwegian goat herd.a control programme for caprine arthritis-encephalitis virus (caev) and corynebacterium pseudotuberculosis (c. pseudotuberculosis) infection was established in a norwegian goat herd comprising approximately 100 milking goats. the herd seroprevalences of antibodies against caev and c. pseudotuberculosis were 97% and 94%, respectively. kids were removed from the infected flock at birth, avoiding any contact between dam and kid. the kids were kept completely segregated from the seropositive flock a ...19989592951
defective rna packaging is responsible for low transduction efficiency of caev-based vectors.replication defective retroviral vectors are regularly used for transfer and expression of exogenous genes into dividing cells and in animals. since lentiviruses are able to infect terminally differentiated and non-dividing cells, their use to produce replication defective vectors may overcome this limitation. we developed two replication-defective lentiviral vectors based on the genome of caprine arthritis encephalitis virus (caev). the first vector (pbnl2) carries the neo and lacz marker genes ...19989638141
priming with tat-deleted caprine arthritis encephalitis virus (caev) proviral dna or live virus protects goats from challenge with pathogenic caev.we previously reported that infection of goats with caprine arthritis encephalitis virus (caev) tat- proviral dna or virus results in persistent infection, since the animals seroconverted and direct virus isolation from cultures of blood-derived macrophages was positive. in this study we wanted to determine whether goats injected with caev tat- proviral dna or virus were protected against challenge with the pathogenic homologous virus and to investigate whether caev tat- was still pathogenic. al ...19989658128
phylogenetic analysis of small ruminant lentiviruses.based on available sequence data, a phylogeny of small ruminant lentiviruses (srlv) was established for env, pol, gag and ltr fragments using maximum likelihood, neighbour-joining and minimum evolution reconstruction techniques. to reconstruct topologies as accurately as possible, phylogenetic parameters like base composition, percentage divergences, kappa, the gamma shape parameter alpha and codon position-specific rates were estimated prior to the reconstruction of trees. divergences between f ...19989714243
pcr detection of lentiviral gag segment dna in the white blood cells of sheep and goats.a pcr assay for the detection of small ruminant lentiviral gag dna (provirus) in the white blood cells of sheep and goats was developed and compared with a serological test (agidt). a sample of the dna prepared from the white blood cells in 3 ml of blood from 208 sheep and goats from 18 different flocks was subjected to pcr assay. one of 85 animals from flocks accredited under the dutch national mvv/caev control programme was positive by pcr while none was positive by agidt. in infected flocks, ...19989778781
maedi-visna virus and caprine arthritis-encephalitis virus: distinct species or quasispecies and its implications for laboratory diagnosis.the lentiviruses responsible for causing maedi-visna or ovine progressive pneumonia in sheep and caprine arthritis-encephalitis in goats have long been considered distinct, albeit related, viral species. evidence, primarily in the form of nucleic acid sequence data, suggests this distinction may not be as absolute as once thought. these lentiviruses might better be viewed in the context of viral quasispecies whose individual members exhibit varying host range and pathogenic capabilities. implica ...19989798087
use of a recombinant maedi-visna virus protein elisa for the serologic diagnosis of lentivirus infections in small ruminants.highly purified recombinant gag and env proteins derived from icelandic strain 1514 of maedi-visna virus were used in an indirect enzyme immunoassay (elisa) to detect antibodies to small ruminant lentiviruses in sheep and goat sera. the recombinant protein-based elisa performed very well relative to whole maedi-visna virus and whole caprine arthritis-encephalitis-virus-based elisas in its ability to detect anti-maedi visna virus and anti-caprine arthritis-encephalitis virus antibodies, despite t ...19989798098
"hidden" dutpase sequence in human immunodeficiency virus type 1 gp120.a coding region homologous to the sequence for essential eukaryotic enzyme dutpase has been identified in different genomic regions of several viral lineages. unlike the nonprimate lentiviruses (caprine arthritis- encephalitis virus, equine infectious anemia virus, feline immunodeficiency virus, and visna virus), where dutpase is integrated into the pol coding region, this enzyme has never been demonstrated to be present in the primate lentivirus genomes (human immunodeficiency virus type 1 [hiv ...19999847382
gag protein epitopes recognized by cd4(+) t-helper lymphocytes from equine infectious anemia virus-infected carrier horses.antigen-specific t-helper (th) lymphocytes are critical for the development of antiviral humoral responses and the expansion of cytotoxic t lymphocytes (ctl). identification of relevant th lymphocyte epitopes remains an important step in the development of an efficacious subunit peptide vaccine against equine infectious anemia virus (eiav), a naturally occurring lentivirus of horses. this study describes th lymphocyte reactivity in eiav carrier horses to two proteins, p26 and p15, encoded by the ...199910196322
conserved sequence motifs involving the tat reading frame of brazilian caprine lentiviruses indicate affiliations to both caprine arthritis-encephalitis virus and visna-maedi virus.the sequence variation in small ruminant lentiviruses from brazilian herds of milking goats was sampled in a representative region of the pol gene and in a region including the entire tat open reading frame. clones were amplified from cdna derived from virus produced in vitro using primers targetting conserved sequences of the pol gene. iterative sequencing of clones indicated that animals from two herds in the minas gerais area were infected by a caprine arthritis-encephalitis virus (caev)-like ...199910423125
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
isolation of caprine arthritis encephalitis virus from goats in mexico.a lentivirus was isolated from 2 goats in mexico that were seropositive to caprine arthritis encephalitis virus (caev) by the agar gel immunodiffusion (agid) test. the lentivirus was identified as caev by the observation of giant multinucleated cells (syncytia) in goat synovial membrane (gsm) monolayers co-cultivated with blood mononuclear (bmn) cells from the seropositive goats, and by amplifying a dna segment of the caev gag gene using the polymerase chain reaction (pcr) technique. subsequentl ...199910480464
how to succeed as a virus: strategies for dealing with the immune system.viruses may be viewed as genetic information whose success depends on avoiding elimination from individual hosts, or, if this is not possible, in persisting in the population of their hosts. the immune system represents the crucial defense mechanism responsible for the elimination of viruses from individual hosts and for the establishment of immunity that prevents a recurring infection by the same virus. herd immunity, i.e., immunity of the population against infection resulting from the immunit ...199910614500
crossreactive neutralizing antibodies induced by immunization with caprine arthritis-encephalitis virus surface glycoprotein.four saanen goats were immunized with affinity purified gp135 surface glycoprotein (su) of caprine arthritis-encephalitis virus isolate 79-63 (caev-63) and evaluated for homologous and crossreactive serum neutralizing antibodies. caev-63 neutralizing antibodies were detected in all goats after seven immunizations with su in quil a adjuvant. sera from three goats neutralized an independent caev isolate (caev-co). however, serum from one goat did not detectably neutralize heterologous caev-co and ...200010649630
experimental infection of mouflon-domestic sheep hybrids with caprine arthritis-encephalitis virus.to determine whether monocyte-derived macrophages from mouflon-domestic sheep hybrids (ovis musimon x ovis spp) were susceptible to productive infection with caprine arthritis-encephalitis virus (caev) in vitro and whether experimental inoculation of mouflon-domestic sheep hybrids with a molecularly cloned caev would result in persistent infection.200010772114
immune response to caprine arthritis-encephalitis virus surface protein induced by coimmunization with recombinant vaccinia viruses expressing the caprine arthritis-encephalitis virus envelope gene and caprine interleukin-12.the objective of this study was to determine if interleukin (il)-12 can focus an antigen specific type 1 immune response characterized by activation of th1 lymphocytes and production of igg2 antibodies in vivo. saanen goats co-immunized with recombinant vaccinia viruses expressing caprine il-12 (rrb-il12) and the caprine arthritis-encephalitis virus (caev) envelope (env) gene (rwr-63) were evaluated for development of immune responses to the caev env encoded surface glycoprotein (su). immune res ...200010775783
the detection of proviral dna by semi-nested polymerase chain reaction and phylogenetic analysis of czech maedi-visna isolates based on gag gene sequences.a semi-nested polymerase chain reaction (snpcr) for detecting proviral dna of ovine lentivirus (ovlv) in peripheral blood mononuclear cells was developed. primers for snpcr were situated within the gag gene of the maedi-visna virus (mvv) genome. a comparison between the snpcr and serological tests (agar gel immunodiffusion test, immunoblot) were performed using 98 ovine blood samples. thirty (30.6%) of the 98 sheep examined had antibodies specific for the mvv. pcr showed 21 of them to be positiv ...200010829575
variability and immunogenicity of caprine arthritis-encephalitis virus surface glycoprotein.the complete surface glycoprotein (su) nucleotide sequences of three french isolates of caprine arthritis-encephalitis virus (caev) were determined and compared with those of previously described isolates: three american isolates and one french isolate. phylogenetic analyses revealed the existence of four distinct and roughly equidistant evolutionary caev subtypes. four conserved and five variable domains were identified in the su. the fine specificities of antibodies produced against these doma ...200010846103
[identification of caprine arthritis encephalitis virus using histopathological, immunohistochemica, and ultrastructural examination of tissues from seropositive goats in mexico].this study demonstrated the presence of viral particles suggestive of arthritis-encephalitis virus through the clinic, serologic, pathologic, immunohistochemic and ultrastructural studies in dairy goats. in the postmortem studies the tissues used were: synovial membrane, lungs and mammary gland from goats with clinical signs characteristic of the disease and positive for serum antibodies to the virus.199810932732
lack of functional receptors is the only barrier that prevents caprine arthritis-encephalitis virus from infecting human cells.barriers to replication of viruses in potential host cells may occur at several levels. lack of suitable and functional receptors on the host cell surface, thereby precluding entry of the virus, is a frequent reason for noninfectivity, as long as no alternative way of entry (e.g., pinocytosis, antibody-dependent adsorption) can be exploited by the virus. other barriers can intervene at later stages of the virus life cycle, with restrictions on transcription of the viral genome, incorrect transla ...200010954533
b-cell epitopes of the envelope glycoprotein of caprine arthritis-encephalitis virus and antibody response in infected goats.goats infected with caprine arthritis-encephalitis virus (caev) develop high titres of antibodies to env. not only is no consistent neutralizing response found but anti-env antibodies have even been associated with disease in infected goats. to identify the continuous antigenic determinants involved in this atypical anti-env response, we mapped caev-co env by screening an epitope expression library with infected goat sera. in addition to the four previously described epitopes, seven novel antige ...200011086124
characterization of chimeric enzymes between caprine arthritis--encephalitis virus, maedi--visna virus and human immunodeficiency virus type 1 integrases expressed in escherichia coli.in order to investigate the functions of the three putative lentiviral integrase (in) protein domains on viral dna specificity and target site selection, enzymatically active chimeric enzymes were constructed using the three wild-type in proteins of caprine arthritis-encephalitis virus (caev), maedi-visna virus (mvv) and human immunodeficiency virus type 1 (hiv-1). the chimeric enzymes were expressed in escherichia coli, purified by affinity chromatography and analysed in vitro for in-specific e ...200111125167
monoclonal antibodies to conformational epitopes of the surface glycoprotein of caprine arthritis-encephalitis virus: potential application to competitive-inhibition enzyme-linked immunosorbent assay for detecting antibodies in goat sera.four immunoglobulin g1 monoclonal antibodies (mabs) to the gp135 surface envelope glycoprotein (su) of the 79-63 isolate of caprine arthritis-encephalitis virus (caev), referred to as caev-63, were characterized and evaluated for their ability to compete with antibody from caev-infected goats. three murine mabs (mabs gpb16a, 29a, and 74a) and one caprine mab (mab f7-299) were examined. all mabs reacted in nitrocellulose dot blots with native caev-63 su purified by mab f7-299 affinity chromatogra ...200111139194
immunization with plasmid dna expressing the caprine arthritis-encephalitis virus envelope gene: quantitative and qualitative aspects of antibody response to viral surface glycoprotein.saanen goats were vaccinated intradermally with plasmid dna expressing caprine arthritis-encephalitis virus (caev) rev-env (penv) or tat-rev-env (ptat-env) or vaccinia virus expressing caev env (rwr-63). sera from all vaccinated goats immunoprecipitated caev surface (su) and transmembrane (tm) glycoproteins with a dominant response to su. antibody response to caev su induced by plasmid dna was relatively biased toward igg2, whereas vaccinia rwr-63 induced predominantly igg1 antibodies to su. dif ...200111166887
testing for cae virus. 200111315149
relationships between infection with caprine arthritis encephalitis virus, intramammary bacterial infection and somatic cell counts in dairy goats.somatic cell counts, the bacteriological condition of the milk and antibodies against caprine arthritis encephalitis virus (caev) were measured monthly throughout lactation in 121 lactating goats of the murcia-granada breed in four commercial dairy goat herds. the prevalence of bacterial intramammary infection was 5.6 per cent and the prevalence of caev infection was 20.6 per cent. an analysis of variance revealed a significant effect of herd, intramammary infection and the interaction between i ...200111430681
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
caprine arthritis encephalitis virus: evidence for a b/d-type assembly pathway in a c-type lentivirus replication.lentiviruses, among which is caprine arthritis encephalitis virus (caev), are known to concomitantly assemble and bud at the plasma membrane of infected cells, in a c-type defined pathway. electron microscopy analysis of caev-infected cells demonstrated viral particles budding at the plasma membrane and into intracellular membrane-surrounded vesicles. furthermore, nonenveloped immature virus-like particles, resembling intracytoplasmic type-a particles (icaps), accumulated within the cytoplasm of ...200111485411
immortalized goat milk epithelial cell lines replicate caev at high level.primary milk epithelial cells were isolated from caev-uninfected goats and three cell lines designated tigmec-1, tigmec-2 and tigmec-3 were established. the three cell lines retained their morphological characteristics of epithelial cells and expressed specific epithelial cytokeratin marker as well as the immortalizing sv40 large t antigen. the kinetics of growth of tigmec1, tigmec2 and tigmec3 cell lines showed a doubling time of 24-48 hours while the parental cell lines became senescent after ...200111592613
viral and cellular specificities of caprine arthritis encephalitis virus vif protein.the caprine arthritis encephalitis virus (caev) vif protein is necessary for a productive infection of susceptible goat cells. the vif gene is conserved among all primate and most nonprimate lentiviruses. however, previous reports demonstrated that, in their respective host cells, primate vif deleted lentiviruses could not be complemented by nonprimate vif proteins, suggesting that species-specific restrictions between vif and the virus-producing cells may modulate the vif function on viral infe ...200211878918
presence of caprine arthritis-encephalitis virus (caev) infected cells in flushing media following oviductal-stage embryo collection.to improve the knowledge on the risk of transmission of the caprine arthritis-encephalitis virus (caev) during embryo manipulations, we conducted a double-nested polymerase chain reaction (pcr) for caev proviral-dna on flushing media recovered from the oviducts 48 h after the beginning of estrus and on blood from 89 donor does. sixty-four does had negative blood and flushing media by pcr. among the 25 caev infected goats (blood pcr positive), 11 were pcr flushing media positive (p < 0.01). cell ...200211991395
epithelial cells from goat oviduct are highly permissive for productive infection with caprine arthritis-encephalitis virus (caev).caprine oviduct epithelial cells (coec) are commonly used in in vitro goat embryo production protocols to stimulate early embryonic development. these feeder cells are usually collected from slaughterhouses from unknown serological status animals for caprine arthritis-encephalitis virus (caev) infection which is frequent in many regions of the world. tissues derived from this source may be contaminated with caev and the use of such material in in vitro fertilisation systems may contribute to tra ...200212135791
early embryonic cells from in vivo-produced goat embryos transmit the caprine arthritis-encephalitis virus (caev).the aim of this study was to investigate whether cells of early goat embryos isolated from in vivo-fertilized goats interact with the caprine arthritis-encephalitis virus (caev) in vitro and whether the embryonic zona pellucida (zp) protects early embryo cells from caev infection. zp-free and zp-intact 8-16 cell embryos were inoculated for 2 h with caevat the 10(4) tissue culture infectious dose 50 (tcid50)/ml. infected embryos were incubated for 72 h over feeder monolayer containing caprine ovi ...200212240918
differential receptor usage of small ruminant lentiviruses in ovine and caprine cells: host range but not cytopathic phenotype is determined by receptor usage.the ovine maedi-visna (mvv) and caprine arthritis-encephalitis (caev) small ruminant lentiviruses (srlv) exhibit differential species tropism and cytopathic effects in vitro. icelandic mvv-k1514 is a lytic srlv which can infect cells from many species in addition to ruminants, whereas a lytic north american mvv strain (85/34) as well as nonlytic mvv strain s93 and caev can infect only ruminant cells. in the present study, we determined if differential receptor usage in sheep and goat cells is th ...200212359443
effect of caprine arthritis-encephalitis virus infection on expression of interleukin-16 in goats.to determine the effect of caprine arthritis-encephalitis virus (caev) infection on expression of interleukin-16 (il-16).200212371770
the role of retroviral dutpases in replication and virulence.several retroviruses, including equine infectious anemia virus (eiav), visna virus, caprine arthritis-encephalitis virus (caev) and feline immunodeficiency virus (fiv) encode dutpase. the role of this enzyme in the replication of these viruses has been scrutinized, with particular emphasis on potential roles for dutpase in virulence and viral mutation rate. overall, the results of these studies have indicated a central role for dutpase in facilitating productive viral replication in non-dividing ...200112374097
eiav, caev and other lentivirus vector systems.lentiviruses that infect non-primates make up a diverse collection of viruses. although these viruses have some features in common with hiv and other primate viruses, differences in genome organization and viral gene function have made the successful derivation of vectors from non-primate lentiviruses unpredictable. this chapter discusses the construction and application of gene transfer systems derived from four non-primate lentiviruses including equine infectious anemia virus (eiav), caprine a ...200112465465
presence of caprine arthritis-encephalitis virus (caev) proviral dna in genital tract tissues of superovulated dairy goat does.transmission of caprine arthritis-encephalitis virus (caev) is not completely understood and the vertical route of infection from the goat to the embryo or to the fetus needs to be investigated. this route of infection involves the presence of caev in the genital tract tissues. prior studies have detected caev-infected cells in genital secretions and in flushing media recovered during embryo collection from infected goats. to specify the origin of these cells, we conducted a double-nested polyme ...200312559456
prime-boost vaccination with plasmid dna encoding caprine-arthritis encephalitis lentivirus env and viral su suppresses challenge virus and development of arthritis.this study evaluated the efficacy of prime-boost vaccination for immune control of caprine arthritis-encephalitis virus (caev), a macrophage tropic lentivirus that causes progressive arthritis in the natural host. vaccination of saanen goats with puc-based plasmid dna expressing caev env induces t helper type 1 (th1) biased immune responses to vector-encoded surface envelope (su), and the plasmid-primed th1 response is expanded following boost with purified su in freund's incomplete adjuvant (su ...200312620804
rapid evolution of two discrete regions of the caprine arthritis-encephalitis virus envelope surface glycoprotein during persistent infection.five major regions of sequence diversity between strains (v1-v5) have been described in the caprine arthritis-encephalitis lentivirus (caev) envelope surface unit glycoprotein (su). to determine which of these variable regions is important in persistent infection in vivo, we evaluated su sequence diversity in five neutralization variants from two goats and proviral dna from five additional goats infected with caev-63 for up to 7 years. overall amino acid sequence divergence in the su encoded by ...200211900835
efficient replication of caprine arthritis-encephalitis virus in goat granulosa cells.recent reports demonstrated the susceptibility of epithelial cells from different organs to caprine arthritis-encephalitis virus (caev) both in vitro and in vivo. since granulosa cells (gc) are of epithelial origin and currently used for in vitro oocyte maturation, we addressed the question whether these cells are susceptible or resistant to caev infection. gc were isolated from goats from certified caev-free herds. pcr analysis on gc dna using caev specific primers confirmed the absence of caev ...200111551657
clearance of a productive lentivirus infection in calves experimentally inoculated with caprine arthritis-encephalitis virus.lentiviruses have long been considered host-specific pathogens, but several recent observations demonstrated their capacity to conquer new hosts from different species, genera, and families. from these cross-species infections emerged new animal and human infectious diseases. the successful colonization and adaptation of a lentivirus to a nonnatural host depends on unspecific and specific host barriers. some of those barriers exert a relative control of viral replication (i.e., cytotoxic t-lymph ...200312743300
plasmid dna encoding caprine interferon gamma inhibits antibody response to caprine arthritis-encephalitis virus (caev) surface protein encoded by a co-administered plasmid expressing caev env and tat genes.this study characterized immune responses of saanen goats co-immunized with puc18 based plasmids expressing caprine arthritis-encephalitis virus (caev) rev-env (penv) or tat-rev-env (ptat-env) and a second plasmid encoding caprine interferon gamma (ifngamma). a previous study reported that immunization with penv or ptat-env induces igg2 biased antibody responses to plasmid encoded caev surface envelope protein (su). we show here that regional lymph nodes (ln) of penv and ptat-env immunized goats ...200111312017
simple and rapid method for production of whole-virus antigen for serodiagnosis of caprine arthritis-encephalitis virus by enzyme-linked immunosorbent assay.polyethylene glycol (peg) was used to produce whole-virus antigen derived from tissue culture cells infected with a canadian strain of caprine arthritis-encephalitis virus. peg antigen batches were obtained after precipitation and concentration of infected tissue culture material with peg 8000 and final treatment with sodium dodecyl sulfate. the optimum time of harvest of tissue culture extracted material to produce the maximum amount of viral proteins was determined in roller bottles, after coc ...200111238221
tryptophan 95, an amino acid residue of the caprine arthritis encephalitis virus vif protein which is essential for virus replication.the caprine arthritis encephalitis virus (caev) vif gene was demonstrated to be essential for efficient virus replication. caev vif deletion mutants demonstrated an attenuated replication phenotype in primary goat cell cultures and resulted in abortive infection when inoculated into goats. in this study, we determined the in vitro replication phenotype of five caev vif point mutant infectious molecular clones and the ability of the corresponding in vitro translated vif proteins to interact with ...200111162837
detection of serum antibodies to ovine progressive pneumonia virus in sheep by using a caprine arthritis-encephalitis virus competitive-inhibition enzyme-linked immunosorbent assay.a competitive-inhibition enzyme-linked immunosorbent assay (celisa) for detection of antibodies to the surface envelope (su) of caprine arthritis-encephalitis virus (caev) was recently reported (l. m. herrmann, w. p. cheevers, t. c. mcguire, d. scott adams, m. m. hutton, w. g. gavin, and d. p. knowles, clin. diagn. lab. immunol. 10:267-271, 2003). the celisa utilizes caev-63 su captured on microtiter plates using the monoclonal antibody (mab) f7-299 and measures competitive displacement of bindi ...200312965917
activation of small ruminant aortic endothelial cells after in vitro infection by caprine arthritis encephalitis virus.small ruminants infected by the lentiviruses caprine arthritis-encephalitis virus (caev), originally isolated from a goat, or maedi-visna virus, originally from sheep, typically develop an organising lymphoid infiltration of affected tissues. this could reflect modulation of the migration pattern of lymphocytes in infected animals. possible active contribution by vascular endothelial cells was investigated using an in vitro model. low-passage cultured ovine aortic endothelium proved susceptible ...200011124093
sequence similarity between the envelope surface unit (su) glycoproteins of primate and small ruminant lentiviruses.sequence similarity has been previously described in the transmembrane domain unit of envelope glycoproteins of primate and non-primate lentiviruses but similarity between the surface unit (su) glycoprotein of these viruses is less clear or absent. here we describe a consistent and significant sequence-similarity between the ovine/caprine lentivirus surface glycoprotein gp135 and the primate lentivirus gp120 in the region between variable loops v2 and v3. the biological relevance of this sequenc ...200010989185
cross-reactivity between caprine arthritis-encephalitis virus and type 1 human immunodeficiency virus.caprine arthritis encephalitis (cae) is caused by the lentivirus caprine arthritis-encephalitis virus (caev), a member of the retroviridae family that also includes the human immunodeficiency virus (hiv). serum of caev-infected goats cross-reacts with hiv-1 antigens in enzyme-linked immunosorbent assay (elisa) tests. we attempted to identify the proteins responsible for this cross-reactivity.200314602501
preliminary survey for antibodies against caprine arthritis-encephalitis virus (caev) using recombinant gag proteins: studies among small ruminant populations in north-eastern nigeria.a total of 1000 serum samples were obtained from small ruminants in maiduguri, borno state, nigeria and tested for the presence of antibodies against caprine arthritis-encephalitis virus (caev) using enzyme-linked immunosorbent assay (elisa) based on p17 and p28 recombinant gag proteins. the distribution of the sera tested was as follows: 900 serum samples collected at slaughter from 700 goats and 200 sheep in the municipal abattoir as well as 100 sera obtained from 50 each of goats and sheep in ...200010818314
establishment and characterization of a goat synovial membrane cell line susceptible to small ruminant lentivirus infection.primary goat synovial membrane (gsm) cells are widely used to study small ruminant lentiviruses (srlv), i.e. maedi visna virus (mvv) and caprine arthritis-encephalitis virus (caev), but their limited life-span of 15-20 passages in vitro is problematic. here, we report that ectopic expression of the catalytic subunit of human telomerase (htert) was sufficient to immortalize primary gsm cells. cultures of htert-transfected gsm cells have been passaged for 2 years without showing any phenotypic dif ...200415081607
seven new ovine progressive pneumonia virus (oppv) field isolates from dubois idaho sheep comprise part of oppv clade ii based on surface envelope glycoprotein (su) sequences.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 greate ...200415084404
the use of phenothiazine dyes to inactivate bovine viral diarrhea virus in goat colostrum.the objectives of this study were to determine the optimal concentration of phenothiazine dye required to inactivate bovine viral diarrhea virus (bvdv) in goat colostrum following 60 min of illumination and determine if immunoglobulin concentration is affected by this technique. in addition, the potential of continuous agitation of colostrum during illumination to affect viral kill was investigated. this experiment was designed to more closely approximate on-farm use than a previous pilot study ...200415188954
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