elevated concentrations in serum immunoglobulins due to infection by ovine progressive pneumonia virus.sixty-seven serum samples were obtained from 2 sheep flocks. agar gel immunodiffusion (agid) was used to separate progressive pneumonia virus (ppv)-infected sheep from noninfected sheep by the presence of precipitating antibodies. immunoglobulin (ig), total protein, and albumin concentrations were then measured from all 67 sera to determine whether differences existed between ppv-infected and non-infected sheep. a significant difference (p less than 0.0005) was found in both total protein and ig ...1979110182
porcine parvovirus: frequency of naturally occurring transplacental infection and viral contamination of fetal porcine kidney cell cultures.the frequency of naturally occurring transplacental infection of swine with porcine parvovirus (ppv) and one of the possible consequences of such infection--the presence of ppv in cell cultures prepared from fetal tissues--were investigated. transplacental infection was indicated by the presence of high titers of hemagglutination inhibiting (hi) antibody for ppv in serums of 0-day-old, hysterectomy-derived, colostrum-deprived pigs of 3 of 82 litters. all letters were farm-raised dams. moreover, ...1975163603
virus-like particles in buffy coat cells of normal goats and goats infected with progressive pneumonia electron microscopy, virus-like particles (vlp) were seen in neutrophils and lymphocytes from buffy coats prepared from 5 goats inoculated with progressive pneumonia virus (ppv) and 3 noninoculated goats. the vlp were 80 to 120 nm in diameter, limited by a unit membrane, and resembled ppv, visna virus, and other members of the oncornavirus family. some vlp seemed to have electron-dense nucleoids and external spikes. in neutrophils, vlp were observed budding into vacuoles; rarely, intravacuola ...1975167620
efficacy of an inactivated virus vaccine for prevention of porcine parvovirus-induced reproductive failure.gilts vaccinated im either once (4 gilts) or twice (2 gilts) with an acetylethyleneimine-inactivated porcine parvovirus (ppv) vaccine before they were bred were subsequently exposed intranasally and orally to virulent ppv at about the 40th day of gestation (from 37 to 43 days). at 2 weeks after vaccination, all had hemagglutination-inhibiting (hi) titers for ppv (from 20 to 80) which decreased by the time the immunity was challenged with virulent virus (from 10 to 40), but increased thereafter ( ...1979464358
serological responses in pigs vaccinated with inactivated porcine parvovirus.the safety and immunogenicity of inactivated porcine parvovirus (ppv) vaccines were investigated. both beta-propiolactone and formalin successfully inactivated virus without destroying immunogenicity, which was considerably enhanced by incorporation of a gel adjuvant in the vaccine. using the formalised-gel vaccine, initial antibody responses were demonstrated in susceptible piglets and adult pigs at 7 days after vaccination. these antibody responses persist at significant levels for at least 6 ...1977565631
replication of porcine parvovirus in peripheral blood lymphocytes, monocytes, and peritoneal macrophages.porcine peripheral blood lymphocytes (pbl), peripheral blood monocytes, and peritoneal macrophages were examined for their ability to support porcine parvovirus (ppv) replication. the cell cultures were infected with the nadl-2 strain of ppv at 0.1 multiplicity of infection. pbl cultures were stimulated with the following phytomitogens: phytohemagglutinin m, concanavalin a, and pokeweed mitogen. unstimulated pbl cultures infected with ppv and uninfected pbl stimulated with phytomitogens served a ...1979574124
[verification of the plum pox virus (ppv) using the tray test (author's transl)].a comparison of 6 host plants reacting by local lesion if infected by the plum pox virus (ppv) demonstrated that beside chenopodium foetidum schrad. also nicandra physaloides (l). gärtner, nicardra physaloides violacea bitter and verbena officinalis l. are pretty well suitable to verify the ppv serving as locally reacting test plants. using the tray test, the ppv was verifiable by separated leaves of c. foetidum schrad., n. physaloides violacea bitter, n. physaloides (l.) gärtner and v. officina ...1978664936
reproductive disease experimentally induced by exposing pregnant gilts to porcine parvovirus.porcine parvovirus (ppv) was administered intravenously or intranasally and orally between the 22nd and the 81st days of gestation to 20 pregnant gilts that were free of hemagglutination-inhibiting (hi) antibody for ppv. gilts were exposed to 1 or both of 2 strains (nadl-7, nadl-2) of ppv and were killed 21 or more days later. fetal and maternal fluids and tissues collected at necropsy were tested for ppv, viral antigen, and hi antibody. transplacental infection occurred with 11 of 12 gilts give ...1976999067
pathogenesis of in utero infection: experimental infection of five-week-old porcine fetuses with porcine parvovirus.injection of porcine parvovirus (ppv) into the allantoic fluid of 3 or 4 fetuses of each of 4 litters of ppv-immune gilts early in gestation (34 to 36 days) resulted in fetal maceration and mummification. a high concentration of virus demonstrated in many tissues of fetuses collected 1 week after initial intraallantoic exposure indicated extensive viral replication. progressively lesser amounts of virus were isolated from tissues of macerated and mummified fetuses collected after longer interval ...19751098529
[examinations concerning the range of host plants of the plum pox virus (ppv) (author's transl)]. 19751242553
[experiments to verify the plum pox virus (ppv) by communicating it on chenopodium foetidum schrad. (author's transl)]. 19751242554
comparison of the virulence of two isolates of porcine parvovirus in 72-day-old porcine fetuses.two strains of porcine parvovirus (ppv), designated kresse and nadl-8, were compared for relative virulence in porcine fetuses. strain kresse was injected into the amniotic fluid of all fetuses of 1 uterine horn of each of 2 pregnant gilts at 72 days of gestation. strain nadl-8 was administered similarly to fetuses of 4 other gilts at the same stage of gestation. all gilts were killed and necropsied 35 days later. selected tissues of all fetuses were tested for infectious virus and viral antigen ...19921325191
immunohistological diagnosis of rabbit haemorrhagic disease (rhd).in the present study the diagnostic use of a biotinylated serum from an immune rabbit was investigated by means of an avidin-biotin-complex (abc)-peroxidase method on paraffin sections. 15 cases of rhd which had been verified histologically and/or by haemagglutination test (ha), 4 suspected cases and 3 cases without history of rhd were included (cases 1 to 22). from 5 prospective cases a wider tissue range was examined (cases 23 to 25 and 29 to 30). furthermore lungs, liver and placenta of 3 fet ...19921325718
the response of pregnant gilts previously given an inactivated preparation of porcine parvovirus (ppv) to challenge infection with a fully virulent ppv.eight 40-day pregnant gilts, previously treated with an adjuvanted-inactivated viral preparation (aivp) obtained with a field strain of porcine parvovirus (ppv) together with 4 pregnant untreated controls, were subjected to challenge infection with a virulent strain of ppv at the 40th day of gestation. after challenge, all controls became febrile for 2 to 8 days, whereas only one gilt among those which had been treated with the aivp experienced fever which lasted 4 days. virus was consistently r ...19921331715
restriction of porcine parvovirus replication in nonpermissive cells.swine testicle (st) cells and madin-darby canine kidney (mdck) cells differ in their ability to support replication of porcine parvovirus (ppv). viral replication events in st cells, a permissive cell type, and mdck cells, a nonpermissive cell type, were compared in an attempt to elucidate putative mechanisms of restrictive virus replication. radiolabeled ppv bound to the cell surface of both cell types equally well and the binding was shown to be ppv specific, indicating that the restriction wa ...19921370555
construction of a chimeric viral gene expressing plum pox virus coat protein.the capsid-encoding gene of plum pox virus (ppv) was fused with the leader sequence of the coat protein mrna (cp) of tobacco mosaic virus by a novel mutagenesis technique which involves reverse transcription of minus-strand rna [synthesized by in vitro transcription of a double-stranded (ds) cdna clone], using an ad hoc synthetic oligodeoxynucleotide as primer. the resulting cdna was rendered ds and cloned into the plasmid, pbluescribe m13+. transcription of this chimeric construction produced r ...19921398133
the complete nucleotide sequence of pepper mottle virus genomic rna: comparison of the encoded polyprotein with those of other sequenced potyviruses.the complete nucleotide sequence of a pepper mottle virus isolate from california (pepmov c) has been determined from cloned viral cdnas. the pepmov c genomic rna is 9640 nucleotides excluding the poly(a) tail and contains a long open reading frame starting at nucleotide 168 and potentially encoding a polyprotein of 3068 amino acids. comparison of the pepmov c presumptive polyprotein with those of other sequenced members of the potyvirus group, including tobacco etch virus (tev), tobacco vein mo ...19921413501
a highly sensitive immunocapture polymerase chain reaction method for plum pox potyvirus detection.a highly sensitive assay, based on polymerase chain reaction amplification of cdna synthesized from the viral rna of antibody-captured viral particles, has been developed for plum pox potyvirus (ppv) detection. the reaction, called immunocapture/pcr (ic/pcr), yields a specific 243-bp product. the immunocapture step, by allowing the use of large sample volumes and by the viral particle prepurification it achieves, dramatically increases the sensitivity of the assay. as few as 8000 target viral pa ...19921430063
stillbirths, mummies, abortions, and early embryonic death.stillbirths, mummies, abortions, and early embryonic death have a substantial impact on the profitability of a farm in both endemic and epidemic conditions. fetal death is highly dependent on stage of gestation. implantation occurs around day 14 postmating in sows, and fetal death of an entire litter at this time usually results in a regular return to service. if more than four embryos remain alive, the sow may go on to farrow normally. if fetal death occurs after implantation but before calcifi ...19921446274
production of porcine parvovirus empty capsids with high immunogenic activity.the vp2 gene of porcine parvovirus was cloned in the baculovirus system and expressed in insect cells. the resulting product was present in high yield. it self-assembled into particles which were structurally and antigenically indistinguishable from regular ppv capsids. a high degree of purity of the recombinant capsids was obtained by ammonium sulphate precipitation of cell lysates. these virus-like particles were used as antigen in the immunization of two pigs. the pigs elicited an immune resp ...19921523879
infectious in vivo transcripts of a plum pox potyvirus full-length cdna clone containing the cauliflower mosaic virus 35s rna promoter.a full-length cdna clone of an aphid non-transmissible isolate of plum pox potyvirus (ppv) was rendered biologically active when placed under the control of the cauliflower mosaic virus 35s rna promoter and the nopaline synthase polyadenylation signal. the cdna was constructed so that the exact 5' end of the ppv rna was present at the transcription initiation site. inoculation of plasmid dna onto nicotiana benthamiana led to systemic infection, whereas local lesions were produced in chenopodium ...19921545225
a monoclonal antibody which recognizes cell surface antigen and inhibits porcine parvovirus replication.monoclonal antibody technologies were applied to the study of early events in porcine parvovirus (ppv) infections in vitro. balb/c mice were immunized with whole swine testicle cells and hybridomas were produced following fusion with myeloma cells. resultant clones were screened firstly in an elisa system, to detect monoclonal antibody recognition of swine testicle cells, and secondly, in a fluorescent antibody test to detect monoclonal antibody which inhibited production of ppv antigen. one clo ...19921562235
proteolytic processing of the plum pox potyvirus polyprotein by the nia protease at a novel cleavage site.the expression of potyvirus genomic rna takes place through translation of its unique long and functional open reading frame into a large polyprotein that undergoes extensive proteolytic processing. most of the cleavages are performed by the virus-encoded nia protease, which cuts the polyprotein at defined sites that are characterized by conserved heptapeptide sequences. we have demonstrated in vitro cleavage activity by the plum pox potyvirus (ppv) nia protease at a novel site, previously ident ...19921585641
nucleotide sequence of the 3'-terminal region of potato virus a rna.the sequence of the 3'-terminal region of the genome of the potato virus a (pva) was obtained from two independent cdna clones. this sequence is 1383 nucleotides long and contains an open reading frame of 1178 nucleotides, ending with the translation termination codon taa and followed by untranslated region of 205 nucleotides. since the n-terminal amino acid of the coat protein of pva was blocked, the position of the putative coat protein cleavage site has been deduced by searching for consensus ...19921604933
experimental in utero infection of pig foetuses with porcine parvovirus (ppv).pig foetuses of various gestational ages were exposed to experimental infection with porcine parvovirus (ppv) in utero. inoculation of 40-, 50- and 60-day-old foetuses with ppv caused foetal death and mummification and spread of the infection to non-inoculated foetuses. inoculation at 80 and 100 days gestation caused pathological lesions of various degrees whereas spread of infection occurred only sporadically. serological examinations of foetuses of different ages suggest that immunocompetence ...19911653481
catalytic antisense rnas produced by incorporating ribozyme cassettes into cdna.a simple strategy is described for the generation of catalytic hammerhead-type ribozymes (rz) that can be used as highly specific endoribonucleases to cleave a particular target rna. the technique requires that a cloned cdna fragment is available which encodes at least a part of the target rna. about 25 different restriction recognition sequences can be utilized to incorporate specifically designed dna cassettes into the cdna. besides some nucleotides which are specific for a certain restriction ...19911660835
outbreaks of porcine parvovirus disease in panama.the first recorded isolation of porcine parvovirus (ppv) in panama is described. the outbreaks of ppv disease were characterised by a high prevalence of mummified foetuses, stillborn and weak pigs and a common source of exposure. diagnosis was based on virus isolation and by demonstrating viral antigen in lungs of affected foetuses. six farms in four different provinces were involved. rapid control of the epizootic was achieved through the use of an inactivated ppv vaccine in the affected farms.19911662424
predicting human immunodeficiency virus type 1-positive sera by using two enzyme immunoassay kits in a parallel testing format.two algorithms for screening sera for antibody to human immunodeficiency virus type 1 were compared for their efficiency in identifying a true-positive sample in a population with heterogeneous risk factors, using the criteria of specificity and positive predictive value (ppv). in the first algorithm, all sera were screened by using a single enzyme immunoassay (eia) kit, and a specificity of 98.6% and a ppv of 69.3% was calculated for true-positive sera. the second algorithm employed two differe ...19911774256
a polymerase chain reaction assay adapted to plum pox potyvirus detection.a sensitive, polyvalent assay based on the polymerase chain reaction (pcr) was developed for plum pox potyvirus (ppv) detection. this technique was adapted for a single tube, the chemical denaturation and reverse transcription of the viral rna followed by the pcr reaction yielding a 243-base-pair product. as few as 10 fg of purified viral rna, corresponding to approximately 2000 viral particles, were detected in plant extracts. all ppv isolates tested were amplified, and the amplified fragments ...19911783677
novel catalytic activity associated with positive-strand rna virus infection: nucleic acid-stimulated atpase activity of the plum pox potyvirus helicaselike protein.the cylindrical inclusion protein of potyviruses contains the so-called nucleoside triphosphate binding motif, an amino acid sequence motif present in proteins encoded by most positive-strand rna viruses, some double-strand rna viruses, apparently all groups of double-strand dna viruses, and also several single-strand dna viruses. further sequence analysis has allowed to include the cylindrical inclusion protein of potyviruses as a member of a superfamily of helicaselike proteins. in this paper ...19911845877
nucleotide sequence of the 3'-terminal region of the rna of the el amar strain of plum pox potyvirus.the nucleotide sequence of the 3'-terminal 4773 nucleotides of the rna of a widely divergent, aphid-transmissible strain of plum pox potyvirus isolated from egypt (ppv-el amar) was determined. the sequenced region covers the carboxy terminus of the cylindrical inclusion (ci) gene, and the putative 6k protein, the nia protease, the nib rna polymerase and the coat protein genes, linked together as one large open reading frame (orf) in a fashion similar to the canonical genomic organization of othe ...19911856701
a pcr membrane spot assay for the detection of plum pox virus rna in bark of infected trees.a procedure for sensitive detection of plum pox virus rna in infected bark of trees is described. the method is based on the extraction of bark material with buffer containing proteinase k followed by partial purification of rna using quiagen anion exchange resin. the rna is then reverse transcribed, the single stranded cdna is amplified by the polymerase chain reaction using biotinylated deoxynucleotides as label. the amplified cdna can subsequently be detected by spotting the reaction mixture ...19911864904
polymerase chain reaction (pcr) amplification for the detection of porcine parvovirus.a polymerase chain reaction (pcr) amplification method was developed and evaluated to detect porcine parvovirus (ppv). a pair of 20-base primers and an oligonucleotide probe were derived from the dna sequences common to two isolates of ppv, nadl-8 and nadl-2. the primers flanked 118-bp nucleotides within the region coding for the major structural protein vp2. after dna amplification of ppv replicative form (rf), a 158-bp fragment was detected in agarose gels. this amplified fragment was shown to ...19911874916
the complete nucleotide sequence of pea seed-borne mosaic virus rna.the complete nucleotide sequence of the rna genome of pea seed-borne mosaic virus (psbmv) was determined from cloned cdna and by direct sequencing of viral rna. the psbmv genomic sequence was determined to be 9924 nucleotides in length excluding the poly(a) tract. the rna contained an open reading frame (orf) of 9618 nucleotides with the potential to encode a polyprotein with a calculated mr of 364000 (364k). the orf was flanked by a 5' untranslated leader sequence of 143 nucleotides and a 3' un ...19911940858
identification of the initiation codon of plum pox potyvirus genomic rna.the expression of plum pox potyvirus (ppv) genomic rna takes place through translation of its unique long and functional open reading frame (orf) into a large polyprotein that undergoes extensive proteolytic processing. in this paper we show that the aug recognized as the initiation codon of the ppv orf by in vitro translation systems is the one found at nucleotide position 147, in spite of the presence at position 36 of an in-phase aug that marks the start of the orf. deletion of a substantial ...19911962436
multiplication of attenuated and virulent porcine parvoviruses in colostrum-deprived, neonatal pigs.colostrum-deprived, neonatal, 2 days old pigs were inoculated with the attenuated ht-/sk or the virulent 90hs strain of porcine parvovirus (ppv) by the oral or subcutaneous route and sacrificed 2, 4 or 6 days after inoculation. then, comparison was made on viral multiplication in pigs between the two strains. pigs inoculated with the ht-/sk strain showed no detectable viremia or hi antibody responses against ppv within 6 days after inoculation. only in pigs inoculated by the subcutaneous route, ...19901962832
detection of porcine parvovirus using nonradioactive nucleic acid hybridization.nonradioactive slot blot hybridization assays were established for the detection of porcine parvovirus (ppv), using either a digoxigenin-labeled dna probe or a biotinylated rna probe. all probes were prepared from a 3.3-kb pst1-ecor1 dna fragment of the nadl8 isolate of ppv. the sensitivity and specificity of the probes in a slot blot system were evaluated in comparison with a 32p-radiolabeled rna probe. using an anti-digoxigenin alkaline phosphatase detection system, at least 1 ng of viral repl ...19901965580
proteolytic activity of plum pox virus-tobacco etch virus chimeric nia proteases.plasmids encoding chimeric nia-type proteases made of sequences from the potyviruses plum pox virus (ppv) and tobacco etch virus (tev) have been constructed. their proteolytic activity on the large nuclear inclusion protein (nib)-capsid protein (cp) junction of each virus was assayed in escherichia coli cells. the amino half of the protease seemed to be involved neither in the enzymatic catalysis nor in substrate recognition. in spite of the large homology among the ppv and tev nia-type protease ...19912015911
plum pox potyvirus rna replication in a crude membrane fraction from infected nicotiana clevelandii vitro synthesis of plum pox potyvirus (ppv)-specific nucleic acid has been measured in a crude fraction prepared from leaves of ppv-infected nicotiana clevelandii plants. using alkali and dnase treatments, the synthesized nucleic acid was shown to be rna. the electrophoretic mobility and the differing sensitivity to rnase at high and low salt concentrations allowed the identification of in vitro products probably corresponding to replicative form and replicative intermediate rna, as well as t ...19912016593
comparison of two rapid methods for detection of respiratory syncytial virus (rsv) (testpack rsv and ortho rsv elisa) with direct immunofluorescence and virus isolation for the diagnosis of pediatric rsv infection.the ability of two commercial immunoassays to detect respiratory syncytial virus (rsv) in respiratory specimens was evaluated as follows: 152 specimens were tested by testpack rsv (abbott), and 72 were tested by ortho rsv elisa (ortho). test outcomes were compared with those of virus isolation alone, direct immunofluorescence assay (dfa) alone, or virus isolation and/or dfa. testpack rsv versus virus isolation showed 91% sensitivity, 96% specificity, 93% positive predictive value (ppv), and 95% ...19912037684
determination of polyprotein processing sites by amino terminal sequencing of nonstructural proteins encoded by plum pox potyvirus.nonstructural proteins of plum pox potyvirus were partially purified following a procedure described for the isolation of tobacco etch virus nuclear inclusion proteins. plum pox virus proteins with electrophoretic mobilities corresponding to 49, 59 and 68 kda reacted with antibodies against the 49 kda and 54 kda components of the nuclear inclusions and the 70 kda component of the cylindrical inclusions of tobacco etch virus, respectively. further purification by size exclusion high performance l ...19902138835
dot hybridization detection of plum pox virus using 32p-labeled rna probes representing non-structural viral protein genes.a cdna library covering the complete genome of plum pox virus strain d (ppv d) has been obtained, and an endonuclease restriction map derived from it. this map was superposed on the ppv genomic organisation map, established for a nonaphid transmissible strain of ppv (maiss et al., 1989). this allowed us to select seven probes, corresponding to different regions on the ppv genome. these probes were tested in a dot-blot hybridization assay for the detection of ppv. probes of various lengths (0.25 ...19902148174
[the effect of parvovirus vaccination in sows through their 4th parity and the role of influenza h1n1 virus].the effects of vaccination of a porcine parvovirus (ppv) in gilts and the first four litters were studied in a pig-breeding herd. in addition to determination of the technical results, ppv and influenza (h1n1) titres were measured. from the serological findings it was apparent that ppv and influenza (h1n1) virus circulated during the trial. the number of total-born and live-born piglets was significantly higher in the first litter when ppv-vaccinated and non-vaccinated gilts were compared. on th ...19902156355
development of a vaccine preventing parvovirus-induced reproductive failure in inactivated porcine parvovirus (ppv) vaccine for the prevention of ppv-induced reproductive failure in pigs was developed, using virus grown in cell culture, inactivated with beta-propiolactone and adjuvanted with aluminum hydroxide. the vaccine was tested for safety by subcutaneous injection into pregnant gilts. there were no signs of abnormal reactions nor evidence of ppv infection in the gilts or their foetuses when they were sacrificed 6 weeks after vaccination. to demonstrate that the va ...19902165775
persistence of porcine parvovirus in swine infected in utero and followed through maturity.the potential of porcine parvovirus (ppv) to persistently infect swine exposed in utero was studied. forty eight 80- to 95-day-old fetuses from 5 ppv seropositive sows were inoculated intramusculary with a virulent strain of ppv or with cell culture medium (controls). blood samples were collected at birth prior to nursing and at monthly intervals thereafter and tested for antibodies to ppv. virus-inoculated and control pigs were euthanized at either 1 week before birth (-1), at birth (0) and at ...19902166412
establishment of transformed swine fibroblast cell lines using sv40 large t antigen.swine testicle cell lines were established by transformation of primary swine testicle (pst) cells with an sv40 plasmid (psv3-neo), which contains genes conferring resistance to neomycin and expressing sv40 large t antigen. plasmid dna was transfected into pst cells using a lipofection system. two related plasmids, psv2-neo and psv5-neo, failed to induce transformed cells. cells transformed with psv3-neo formed single colonies that were resistant to the antibiotic, g418, and expressed large t an ...19902175590
comparison of commercial kits for the detection of antibody to human immunodeficiency virus type 1 (hiv-1) in nigeria.four commercial kits for the detection of antibodies to hiv-1 were compared with regard to their sensitivity, specificity and positive predictive value. the wellcozyme competitive enzyme immunoassay was the least sensitive (62.5%), while roche eia, was the most sensitive (100%). all the commercial kits gave false negative results except the roche eia system. the serodia particle agglutination test had the least positive predictive value of 26.9% while roche eia had the highest (88.9%). our resul ...19902191859
detection of the trans activity of the plum pox virus nia-like protease in infected plants.the nia-like protein of plum pox virus is a protease with high sequence specificity that is autocatalytically released from the viral polyprotein. in order to determine whether the protease is active in trans we constructed a fusion protein consisting of the c-terminal region of the plum pox virus polyprotein and the staphylococcal protein a. the authentic protease recognition sequence asn-val-val-val-his-gln-ala occurs in the centre of this protein fusion. this protein was cleaved specifically ...19902197372
sensitive enzyme immunoassay for the rapid diagnosis of influenza a virus infections in clinical specimens.samples of nasopharyngeal secretion (nps) from 100 infants and small children admitted for acute respiratory disease during the period from january to march 1989 were examined for the presence of influenza a virus. all samples were tested by enzyme immunoassay (eia), fluorescent antibody (fa) technique and by isolation in cell culture 3-6 h after they were obtained from the patients. of 24 influenza strains found by isolation, 21 were detected by eia and 19 were fa+. in comparison with virus iso ...19902203125
replication of two porcine parvovirus isolates at non-permissive temperatures.previous studies have shown that replication in vitro of the porcine parvovirus (ppv) isolate, kbsh, was restricted at 39 degrees c but not at 37 degrees c. in contrast, replication of the kresse isolate was restricted at 37 degrees c but not at 39 degrees c. in this study, kresse and kbsh isolates were passaged up to ten times in swine testicle (st) cells at non-permissive temperatures, and at subsequent passage viral protein synthesis, viral dna synthesis, and progeny virus were evaluated. kbs ...19902222184
rna helicase: a novel activity associated with a protein encoded by a positive strand rna virus.most positive strand rna viruses infecting plants and animals encode proteins containing the so-called nucleotide binding motif (ntbm) (1) in their amino acid sequences (2). as suggested from the high level of sequence similarity of these viral proteins with the recently described superfamilies of helicase-like proteins (3-5), the ntbm-containing cylindrical inclusion (ci) protein from plum pox virus (ppv), which belongs to the potyvirus group of positive strand rna viruses, is shown to be able ...19902263459
mutational analysis of plum pox potyvirus polyprotein processing by the nia protease in escherichia coli.a binary escherichia coli expression system has been used to study the pathway for proteolytic processing of the plum pox potyvirus (ppv) polyprotein. trans cleavage at the carboxyl end of the cylindrical inclusion protein occurred, although with lower efficiency than that at the large nuclear inclusion protein-capsid protein junction. no trans cleavage at the carboxyl end of the small nuclear inclusion protein (nia) was detected. the proteolytic activities at different cleavage sites of several ...19902273380
excretion of porcine parvovirus through the genital tract of boars.the putative binding of porcine parvovirus (ppv) to semen components in vitro was examined along with the shedding pattern of ppv in oronasally infected boars. porcine parvovirus dna was determined to be bound to spermatozoa that had been incubated in vitro with ppv and washed to remove loosely adherent virus. to determine whether ppv was shed in the semen, four 8-month-old boars, seronegative for ppv, were inoculated oronasally with a virulent strain of ppv. prior to virus inoculation, a cathet ...19902316910
infectious in vitro transcripts from a plum pox potyvirus cdna clone.a full-length cdna clone of the 9786 nt plum pox virus (ppv) rna genome has been cloned downstream from a phage t7 rna polymerase promoter. the rnas synthesized by in vitro run-off transcription in the presence of the 5' cap analog m7gpppg were infectious in nicotiana clevelandii plants. no infectivity was detected when the transcriptions were carried out in the absence of the cap analog. inoculations of the local lesion host chenopodium foetidum indicated that the infectivity of the synthetic t ...19902371774
antigenic relationships among autonomous parvoviruses.the antigenic relatedness of minute virus of mice (mvm), kilham rat virus (kr), h-1 virus (h-1), haemorrhagic encephalopathy of rats virus (her), porcine parvovirus (ppv), canine parvovirus (cpv), feline panleukopenia virus (fpv), goose parvovirus (gpv) and bovine parvovirus (bpv) was studied by immunofluorescence microscopy (fa) and by serum neutralization (sn). an antigenically related group comprising mvm, kr, her, ppv, cpv and fpv was recognized by fa and most reactions within the group were ...19862432167
antigenic and structural variation of the p28 core polypeptide of goat and sheep retroviruses.the p28 core polypeptides of four isolates of caprine arthritis-encephalitis virus (caev) from goats was compared with those of visna virus (vv) and progressive pneumonia virus (ppv) from sheep. monoclonal antibodies recognized p28 epitopes common to all six retrovirus isolates, a p28 epitope on four caev isolates, but not vv and ppv isolates, a p28 epitope on four caev isolates and vv, but not ppv and a p28 epitope unique to the caev isolate used for immunizing the mouse spleen donor. compariso ...19872440985
early screening for anti-plum pox virus monoclonal antibodies with different epitope specificities by means of gold-labelled immunosorbent electron microscopy.the technique of gold-labelled immunosorbent electron microscopy for the initial screening of monoclonal antibodies 10 days after cell fusion from 96-well culture plates is described. the technique is used to identify clones that secrete antibodies binding on the surface of the virion or to viral subunits, and compared to elisa and western blotting. high sensitivity was demonstrated.19882464610
evaluation and simplification of the world health organization clinical case definition for paediatric aids.the world health organization (who) clinical case definition for paediatric aids was tested during a 1-month period on 221 consecutive hospitalized children in kigali, rwanda. relevant clinical features not included in the who case definition were also evaluated. thirty-four out of the 221 children (15.4%) were hiv seropositive. although the specificity of the who case definition was high (92%), the sensitivity and the positive predictive value (ppv) were low (41 and 48%, respectively). the foll ...19892500955
a serological survey of swine parvovirus infection in italy.a serological survey to detect the presence of porcine parvovirus (ppv) infection in italy and its geographic distribution was conducted. 1,332 samples of serum collected in 1983/1984/1985 were taken from pig breeding herds and, to a lesser extent, from fattening piggeries of representative regions of italy. they were tested using the hemagglutination inhibition test (hit). the results of the serological study indicate that parvovirus infection is widespread in italian herds having 70.3% of sera ...19892550741
the complete nucleotide sequence of plum pox virus rna (strain d). 19892602121
expression of the plum pox virus coat protein region in escherichia coli.a cdna complementary to the 3' end of plum pox virus (ppv) rna was sequenced. the sequence was investigated for the presumable coat protein cistron by computer-aided translation. a fragment containing the stop codon of the polyprotein gene and a putative virus-specific protease cleavage site was subcloned into an e. coli expression vector. it is shown by immunological analysis that the coat protein cistron is located within the subcloned region.19892655276
artificial cleavage site recognized by plum pox potyvirus protease in escherichia coli.a synthetic plum pox virus (ppv) nib-cp cleavage site was recognized by a ppv protease in an in vivo escherichia coli expression system. the presence of the natural nib-cp cleavage site did not affect processing at the artificial one. however, although both the proteases and the cleavage sites of ppv and tobacco etch virus show high sequence homology, a similar cassette from the tobacco etch virus nib-cp junction was not efficiently recognized by the ppv protease.19892657098
proteolytic activity of the plum pox potyvirus nia-like protein in escherichia coli.the nucleotide sequence of the small nuclear inclusion protein (nia)-like cistron of plum pox potyvirus (ppv) has been determined. viral proteolytic activity was expressed in escherichia coli cells harboring plasmids with a ppv cdna insert approximately 7000 nt long. free ppv capsid protein was detected in these cells, but it was not produced when a mutation was introduced in the ppv cdna insert which induced a gln to pro substitution at the large nuclear inclusion protein (nib)-capsid protein j ...19892658302
proteolytic activity of the plum pox potyvirus nia-protein on excess of natural and artificial substrates in escherichia coli.the plum pox potyvirus (ppv) nia protease expressed from a medium copy number plasmid was able to process an excess of substrate expressed from a high copy number plasmid, in a binary escherichia coli expression system. the delta b7 nia protease mutant only partially processed the nib-cp junction but its efficiency was independent of the amount of substrate. the delta b7 mutant essentially did not recognize an artificial cleavage site which was quite efficiently recognized by the wild-type prote ...19892684687
nucleotide sequence of the 3'-terminal region of potato virus yn rna.the sequence of the 3'-terminal 1611 nucleotides of the genome of the tobacco veinal necrosis strain of potato virus y (pvyn) was determined. the sequence revealed an open reading frame of 1285 nucleotides, of which the start was not identified, and an untranslated region of 316 nucleotides upstream of a poly(a) tract. comparison of the open reading frame with the amino-terminal sequence of the viral coat protein enabled mapping of the start of the coat protein at amino acid -267, and indicated ...19892732687
the complete nucleotide sequence of plum pox virus rna.the complete nucleotide sequence of the rna of an aphid non-transmissible plum pox virus (ppv-nat) isolate has been determined from five overlapping cdna clones. cdna prepared by primer extension was used to determine the 5' terminus. the assembled rna is 9741 nucleotides in length, excluding a 3' terminal poly(a) sequence. one large open reading frame starts at nucleotide positions 36 to 38 and is terminated with an uag codon at positions 9522 to 9524. the putative start codon is located at pos ...19892732699
the complete nucleotide sequence of plum pox potyvirus rna.the complete nucleotide sequence of the plum pox virus (ppv) rna genome has been determined. the rna sequence is 9786 nucleotides in length, excluding the 3'-terminal poly(a) tail. an aug triplet at position 147-149 was assigned as the initiation codon for the translation of the genome size viral polyprotein which would consist of 3140 amino acid residues. the nucleotide sequence of the non-coding regions and the predicted amino acid sequence of the polyprotein of ppv were compared with those pr ...19892773595
porcine parvovirus: dna sequence and genome organization.we have determined the nucleotide sequence of an almost full-length clone of porcine parvovirus (ppv). the sequence is 4973 nucleotides (nt) long. the 3' end of virion dna shows a y-shaped configuration homologous to rodent parvoviruses. the 5' end of virion dna shows a repetition of 127 nt at the carboxy terminus of the capsid proteins. the overall organization of the ppv genome is similar to those of other autonomous parvoviruses. there are two large open reading frames (orfs) that almost enti ...19892794971
the genome-linked protein and 5' end rna sequence of plum pox potyvirus.the infectivity of plum pox potyvirus (ppv) rna was decreased by treatment with proteases. ribonuclease digestion of iodinated ppv rna yielded material which had an electrophoretic mobility corresponding to mr 22,000. this protein presumably corresponds to the protease-sensitive structure needed for infectivity. a protein-linked rnase t1-resistant oligonucleotide, 38 nucleotides long, was sequenced and shown to correspond to the 5' terminus of the rna by sequence comparison to the rnas of two ot ...19892794981
pathogenicity of a skin isolate of porcine parvovirus in swine fetuses.the pathogenic properties of a skin isolate of porcine parvovirus (ppv), designated kresse isolate, were compared with nadl-8 isolate, a prototype isolate of ppv, by in utero inoculation of mid-term and late-term gestation swine fetuses. fetuses from pregnant sows of mid-gestation were inoculated with either nadl-8 or kresse virus. both isolates were highly pathogenic to mid-gestation fetuses. in contrast, dramatic differences in pathogenicity between these 2 isolates were observed in fetuses in ...19872830705
[experimental studies on maedi-visna].in order to study pathogenicity of sheep lentiviruses, to obtain monospecific sera and to perfect elisa, 3 experiments with different strains were carried out for 4 yr. in expt 1, one clone only of a french maedi-visna strain (564-79) elicits a clear seroconversion in inoculated sheep. in expt 2, k1514 is more immunogenic than k796 and ppv: intratracheal route seems more efficient than intracerebral route. sheep infected by ts mutants (expt 3) are early positive as wild strain k796. nevertheless ...19882838220
precipitating antibodies in experimental visna and natural progressive pneumonia of sheep.serological responses of icelandic sheep experimentally infected with visna virus (vv) were contrasted with responses in american targhee sheep naturally infected with progressive pneumonia virus (ppv). precipitating antibodies assayed by immunodiffusion were compared with the neutralising and complementing fixing antibody response. in experimental infections with vv, complement fixing and neutralising antibodies appeared early after infection and rose to high levels in all sheep, while precipit ...19852988088
radioimmunoassay of adjuvant-associated porcine parvovirus using a monoclonal antibody in a nitrocellulose membrane system.a quantitative and simple indirect radioimmunoassay (iria) was developed for porcine parvovirus (ppv), employing a monoclonal antibody directed against ppv adsorbed to nitrocellulose membrane. the iria was equally sensitive to live or inactivated ppv. there was a linear relationship between membrane-bound radioactivity and ppv quantity within a range of 10-80 hemagglutinating (ha) units of virus. two commercially used adjuvants, aluminum hydroxide (ah) and carboxyvinyl polymer (cp), reduced boun ...19853009510
comparison of porcine parvovirus to other parvoviruses by restriction site mapping and hybridization analysis of southern blots.the genomic relationship between porcine parvovirus (ppv) and several other autonomous parvoviruses was examined by restriction site and hybridization analysis. restriction site maps of the ppv genome were prepared by digesting the double-stranded replicative form of the viral dna with each of eight restriction enzymes. subsequent comparison of such maps with those previously reported for ppv, canine parvovirus (cpv), feline panleukopenia virus (fpv), minute virus of mice (mvm), h-1 virus (h-1) ...19873029312
study of the efficacy of an inactivated virus vaccine against porcine parvovirus.the efficacy of an inactivated virus vaccine against porcine parvovirus has been studied by immunizing 4 sows during pregnancy. a parvovirus virulent strain has been inoculated to these sows and to two other unvaccinated sows used as controls. the infection was performed between the 52nd and the 57th day of gestation. in the litters born from the vaccinated sows, 82% of the piglets were alive and normal. neither ppv antibodies nor antigen could be revealed in the stillborn fetuses born from the ...19863030182
hormonal changes in sows after induced porcine parvovirus infection in early pregnancy.hormonal changes, lesions, and virus isolation studies were determined in sows after uterine artery inoculation with porcine parvovirus [( ppv], strain nadl-8) in early pregnancy. two sows were given ppv on days 14 or 16 and were euthanatized and necropsied on day 35 after twice daily plasma collection for hormone measurement. parvovirus was given to 4 sows on day 14 and to 4 sows on day 21 with 5 times daily plasma samples collected for 1 week. sows were examined on days 21 and 28, respectively ...19873035969
clinical, virologic, and histopathologic observations of induced porcine parvovirus infection in boars.twelve 8- to 12-month-old crossbred boars were inoculated with a virulent strain (nadl-8) of porcine parvovirus (ppv). hemicastrations were performed on 6 boars 3, 7, 10, 14, 21, and 28 days after an im injection of 10(8) median cell culture infectious dose (ccid50) of ppv (n = 3) or injection of 10(7.4) ccid50 given intratesticularly (it, n = 3). noninfected cell culture medium (0.25 ml) was injected into each testicle of a 7th boar (it inoculated control). virus or viral antigen was detected i ...19873035971
inhibition of porcine parvovirus replication by empty virus particles.the influence of empty porcine parvovirus (ppv) particles on viral replication was examined in cell cultures and in swine. following extensive purification, homogeneous preparations of full and empty ppv preparations were obtained and used for in vitro and in vivo analyses. in the first in vitro experiment, swine testes cells were infected with mixtures of various ratios of empty and full (e/f) particles. the production of both intracellular and extracellular virus was markedly inhibited in the ...19873039947
porcine parvovirus: replication in and inhibition of selected cellular functions of swine alveolar macrophages and peripheral blood lymphocytes.the ability of four isolates of porcine parvovirus (nadl-8, nadl-2, kbsh, and kresse) to replicate in and affect the functions of swine peripheral blood lymphocytes and alveolar macrophages was studied in vitro. v-strand and c-strand viral dna was present in both concanavalin a- and non-treated lymphocytes as well as alveolar macrophages following infection with all four isolates. indirect fluorescent antibody assays on swine testis cells, inoculated with cell lysates of nadl-8-infected peripher ...19883046562
size and antigenic comparisons among the structural proteins of selected autonomous parvoviruses.the size and antigenic relationships among structural proteins (vps) of canine parvovirus (cpv), feline parvovirus (fpv), porcine parvovirus (ppv), minute virus of mice (mvm) and bovine parvovirus (bpv) were determined by sds-page of radiolabelled, purified virus and immunoprecipitated viral proteins. mature virions of cpv, fpv, ppv and mvm were composed of three vps designated vp1, vp2 and vp3. the corresponding proteins of each virus were similar in molecular weight [79,000 to 82,500 (vp1), 65 ...19883356979
uptake of porcine parvovirus into host and nonhost cells suggests host specificity is determined by intracellular factors.the uptake of porcine parvovirus (ppv) into host cells, permissive or nonpermissive for ppv replication, was monitored by autoradiography, immunofluorescent microscopy, and dual parameter flow cytometry. while both permissive and nonpermissive cells selectively took up the light (activated) form of the virus from a mixed population of heavy and light infectious virions, the virus was only replicated in the permissive cell cultures. transfection of permissive and nonpermissive cells with purified ...19883376550
[2 strains of swine parvoviruses isolated from aborted fetuses].two hemagglutinating virus strains were isolated (in primary cell cultures of pig kidneys) from viscera of aborted swine fetuses. a number of serologic, cytologic, physico-chemical, and laboratory investigations with the strains revealed that they belonged to the group of porcine parvovirus (ppv). the isolation of spv from aborted fetuses pointed to the fact that the disease had been widespread among the swine population and plays a part in reproduction disturbances that have come to be known re ...19873617471
identification and characterization of a porcine parvovirus nonstructural polypeptide.sera from porcine parvovirus (ppv)-infected swine fetuses immunoprecipitated and 84- to 86-kilodalton polypeptide in addition to the a and b virion structural proteins. this polypeptide, designated ns-1, was present in ppv-infected cell lysates but not in purified virions. partial proteolysis mapping revealed that ns-1 was not related to the a and b viral structural proteins. all three proteins in infected cells were phosphorylated at serine residues, and ns-1 also contained phosphothreonine. fr ...19854020958
transformation of murine cells by two "slow viruses," visna virus and progressive pneumonia virus.visna and progressive pneumonia virus (ppv), two antigenically related, non-oncogenic "slow viruses" which have ribonucleic acid (rna)-dependent deoxyribonucleic acid (dna) polymerase activity, were examined for their ability to transform cells. murine cells which had been exposed to either visna or ppv developed foci of altered, spindle-shaped cells 3 to 4 weeks after infection. visna and ppv transformed lines were established from these cultures. there was no evidence that other oncogenic dna ...19714998321
[localization and migration of the sarka virus (plum pox virus)]. 19695396079
porcine parvovirus dna: characterization of the genomic and replicative form dna of two virus isolates.the genomic and replicative form (rf) dna of porcine parvovirus (ppv) have been characterized. ppv isolate nadl-8 was found to have a 5000-base single-stranded genome, and a unique strand was encapsidated in virus particles. the rf dna of isolate nadl-8 was found to be an infectious 5000-base pair (bp) molecule. select restriction endonuclease sites were mapped along the rf dna of ppv (nadl-8), and oriented with respect to the viral genomic dna. the rf dna of a second isolate of ppv, the less pa ...19846091327
biological assay of attenuated strain nadl-2 and virulent strain nadl-8 of porcine parvovirus.attenuated strain nadl-2 and virulent strain nadl-8 of porcine parvovirus (ppv) were titrated in vivo and in vitro under similar conditions to provide a better understanding of some of the factors involved in virulence of ppv in causing maternal reproductive failure of swine. both strains cause fetal death when they are injected directly into fetal fluids, but only strain nadl-8 does so when administered to pregnant swine. the strains were tested for their hemagglutinating activity (ha), median ...19846098200
oronasal and intramuscular vaccination of swine with a modified live porcine parvovirus vaccine: multiplication and transmission of the vaccine attenuated strain nadl-2 of porcine parvovirus (ppv) has been used at the 54th cell culture passage as a modified live-virus (mlv) vaccine. the present study was conducted to determine the minimum immunizing dose of mlv, the extent of mlv multiplication in swine tissues, and its transmission from swine administered mlv oronasally or intramuscularly. immune response to mlv was dose dependent and swine responded to as little as 10(2) median cell-culture infective doses (ccid50). a 10(5) ccid50 ...19846098202
morphological and immunological comparison of caprine arthritis encephalitis and ovine progressive pneumonia viruses.caprine arthritis encephalitis virus (caev) causes a variety of pathological conditions ranging from mild to very severe and from acute to chronic, depending upon the age of initial infection and other variables. although the virus has been reported to have properties of characteristic of retroviruses and to be related to maedi-visna virus (also called progressive pneumonia virus [ppv]), relatively little information about its morphological and immunological characteristics has been reported. we ...19816169845
antibody response of pigs to inactivated monovalent and bivalent vaccines for porcine parvovirus and pseudorabies virus.groups of pigs vaccinated with an inactivated bivalent vaccine containing porcine parvovirus (ppv) and pseudorabies virus (prv) developed geometric mean titers (gmt) of humoral antibody for each of the viruses as high or slightly higher than those of other groups of pigs that were vaccinated with inactivated monovalent vaccines containing one or the other of the same viruses. an increase in gmt after challenge exposure of vaccinated pigs to live virus indicated that vaccination did not prevent v ...19806261613
laboratory evaluation of selected disinfectants as virucidal agents against porcine parvovirus, pseudorabies virus, and transmissible gastroenteritis virus.of a variety of disinfectants evaluated, only sodium hypochlorite and sodium hydroxide inactivated porcine parvovirus (ppv) after a 5-minute incubation period. after the same incubation time, pseudorabies and transmissible gastroenteritis viruses were inactivated by all of the disinfectants tested. when the incubation time was increased to 20 minutes, 2% glutaraldehyde and a double-strength concentration of a commercial formaldehyde preparation also inactivated ppv. formaldehyde vapor and ultrav ...19816269467
ovine progressive pneumonia: pathologic and virologic studies on the naturally occurring disease.pathologic and virologic studies were conducted on 13 mature ewes with serum precipitin antibodies to progressive pneumonia virus (ppv). pulmonary lesions of ovine progressive pneumonia were found in 4 sheep, a meningoencephalitis resembling visna in 1 sheep, chronic proliferative carpal arthritis in 2, and massive lymphoid proliferation in the mammary gland in 3. virus producing cytopathic effect typical of ppv was isolated from the lungs, mediastinal lymph node, spleen, and choroid plexus of 4 ...19816275756
pseudorabies virus, porcine parvovirus, and porcine enterovirus interactions with the zona pellucida of the porcine embryo.porcine embryos (n = 93) were incubated on cell monolayers that had been previously inoculated with pseudorabies virus, porcine parvovirus (ppv), or each of 2 porcine enteroviruses. after 2, 24, or 48 hours of incubation, the embryos were fixed in glutaraldehyde and examined by electron microscopic procedures. it was found that pseudorabies virus adsorbed to the zona pellucida (zp) and entered sperm tracks in the zp. the ppv and both enteroviruses entered pores in the zp and were associated with ...19836307093
experimental infection of sheep by caprine arthritis-encephalitis virus and goats by progressive pneumonia virus.the lentiviruses, caprine arthritis-encephalitis virus (caev) and progressive pneumonia virus (ppv) of sheep, cause major diseases in their respective hosts; however, the infectivity of these viruses for closely related species has not been determined. experiments were conducted to determine whether caev would infect sheep and whether ppv would infect goats. upon inoculation with caev, lambs developed a nonsuppurative arthritis and antibody to caev, and the virus was isolated up to 4 months late ...19836318613
an inactivated, oil-emulsion vaccine for the prevention of porcine parvovirus-induced reproductive failure.pig fetuses inoculated at 45 days gestation with virulent porcine parvovirus (ppv) were harvested 10 days later. virus was extracted, inactivated with binary ethylenimine and the antigen suspension emulsified with mineral oil adjuvant. one dose of this vaccine, or two doses with a 14 day interval, stimulated high and long lasting serum antibody titres in gilts. vaccination caused no clinical reactions and lesions at injection sites were minor. vaccination of seronegative gilts at 40 days gestati ...19846326214
the pattern of endemic parvovirus infection in four pig herds.serological surveys were conducted on the gilts and adult sows in 4 herds endemically infected with porcine parvovirus. the study assessed the influence of the type of management of breeders on the spread of virus infection and the influence of endemic parvovirus infection on reproductive parameters of the herd. the practice of holding gilts and sows in groups did not reliably promote infection or maintain a 100% level of active immunity amongst adult sows in 2 of 3 group husbandry herds. in the ...19836626062
antibody responses of guinea-pigs, rabbits and pigs to inactivated porcine parvovirus vaccines.antibody responses were compared in guinea-pigs, rabbits and pigs following vaccination with inactivated porcine parvovirus (ppv) vaccines. mean ppv hemagglutination inhibition (hi) antibody titers of 52, 56 and 36 at 1 week after first vaccination and 896, 640 and 512 at 2 weeks after second vaccination were detected in guinea-pigs, rabbits and pigs, respectively. ppv vaccines prepared with greater concentrations of virus, as determined by hemagglutination (ha) units, and of aluminum hydroxide ...19846719818
porcine parvovirus: virus purification and structural and antigenic properties of virion polypeptides.porcine parvovirus (ppv) was extensively purified from infected swine fetal homogenates by cacl2 precipitation followed by cscl density centrifugation. two species of particles possessing ppv-specific hemagglutinating activity were observed banding at densities of 1.39 and 1.30 g/ml, representing full and empty 20-nm virion particles, respectively. both classes of particles contained three major polypeptides. a, b, and c, with respective molecular weights of 83,000, 64,000, and 60,000. the amoun ...19836834473
role of the rat in the transmission of porcine parvovirus.rats experimentally inoculated with porcine parvovirus (ppv) shed virus in excreta from 3 to 21 days. rats inoculated subcutaneously with ppv responded serologically with hemagglutination-inhibition titers (512-1,024). the ppv antigen was readily detected in lung and spleen 2 and 3 days after rats were inoculated and in liver and intestine, 4 days. the rats remained clinically healthy. rats given ppv orally or in drinking water either with ppv-infected cell culture fluid or swine fetal homogenat ...19827073064
evaluation of a modified live-virus vaccine for the prevention of porcine parvovirus-induced reproductive disease in swine.each of 5 gilts was vaccinated im with modified live-virus (mlv) vaccine for porcine parvovirus (ppv), and 5 gilts were used as nonvaccinated controls. vaccinated gilts developed hemagglutination-inhibiting (hi) antibodies to ppv (titer of 320 to 1,280) by 2 weeks after vaccination. all gilts wee bred, and at about 40 days of gestation their immunity was challenged by intranasal and oral administration of a virulent strain of ppv. gilts were killed at about 84 days of gestation and their litters ...19807212434
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