Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| immune response in pigs to aujeszky's disease viruses defective in glycoprotein g1 or gx. | two aujeszky's disease virus glycoprotein genes, gx and g1, have been used to produce deletion mutants which have then been developed into vaccines. these deletions then allow differentiation between pigs infected with wild type virus and those given the vaccine. it is not clear whether the glycoproteins encoded for by these genes are needed to induce a full protective immune response, in which case deletion mutants would suffer from lack of potency. to test this, commercially available aujeszky ... | 1991 | 1852057 |
| conjunctivitis associated with a mycoplasma-like organism in swine. | a midwestern producer reported high incidence of conjunctivitis and keratoconjunctivitis in a herd of crossbred finishing swine. complete necropsy was performed on 3 pigs with bilateral mucopurulent conjunctivitis and chemosis; other gross lesions were not seen. mycoplasma sp was isolated from conjunctival swab specimens obtained from 1 pig; small numbers of streptococci and coagulase-negative staphylococci were isolated from conjunctival swab specimens from all 3 pigs. neither swine influenza v ... | 1991 | 2010341 |
| sources of antibody-dependent cellular cytotoxicity deficiency in young pig leukocytes. | antibody-dependent cellular cytotoxicity (adcc) activity against pseudorabies virus-infected target cells has been found to be lower in young pig peripheral blood leukocytes (pbls) than in adults. experiments were designed to investigate the reason(s) for low activity in the young, which are more at risk of fatal infection than adults. the percentage of polymorphonuclear leukocytes (pmns), the major adcc effector cell, in the whole leukocyte population did not have a bearing on the deficiency. e ... | 1991 | 1825501 |
| pseudorabies virus infections in explants of porcine nasal mucosa. | the spread of infection and the morphogenesis of three pseudorabies virus strains were studied in explants of porcine nasal mucosa. virulent nia-3 virus was compared with a deletion mutant 2.4n3a, and with a non-virulent bartha virus. all three virus strains infected nasal epithelial cells. nia-3 virus particles were enveloped mainly at the inner nuclear membrane; the virus rapidly invaded the stroma, causing widespread necrosis. in contrast, 2.4n3a virus particles were enveloped mainly at the e ... | 1991 | 1646473 |
| prevalence of pseudorabies virus infection and associated infections in six large swine herds in illinois. | sera were collected from 6 large farrow-to-finish swine herds infected with pseudorabies virus (prv) in illinois. all herds were participating in the large herd cleanup study, a usda-initiated project to evaluate the feasibility of eradicating pseudorabies from large farms (greater than 400 sows) by use of a combination of vaccination and management changes. herd size ranged between 425 and 1,500 breeding females. between april and july 1990, sera for measurement of prv antibodies were obtained ... | 1991 | 1651912 |
| factors associated with spread of pseudorabies virus among breeding swine in quarantined herds. | knowledge of the factors that place susceptible gilts at highest risk of pseudorabies virus (prv) infection in a quarantined herd is crucial to reduce spread of prv within the herd. cohorts of prv seronegative gilts were monitored in 17 herds that were endemically infected with prv to determine the location of breeding females at the time of infection with prv and identify herd characteristics and management and housing factors that may influence spread of prv in the breeding section of swine he ... | 1991 | 1653190 |
| anamnestic immune response of pigs to pseudorabies virus: latent virus reactivation versus direct oronasal and parenteral exposure to virus. | the humoral antibody response of pseudorabies-immune pigs to reactivation of latent pseudorabies virus (prv) was compared with the response following direct exposure to virulent prv. nine pigs that had been vaccinated for pseudorabies and later exposed to virulent virus to establish latent infection were given dexamethasone to reactivate latent virus (3 pigs), were exposed oronasally and parenterally to virulent virus (3 pigs), or were kept as nontreated controls (3 pigs). sera collected from al ... | 1991 | 1654132 |
| spread and control of aujeszky's disease (ad). | the review deals with practical aspects of control and eradication of aujeszky's disease (ad) and the various factors concerned with it. these are resistance of virus to environmental conditions, amounts of virus necessary for infection, virus excretion, virus latency, mode of virus transmission, and vaccination. notification of ad is a precondition of control. several measures are necessary on the infected farm to prevent virus spread. eradication can be done by slaughter of all the seropositiv ... | 1991 | 1657510 |
| characterization of complement-independent neutralizing epitopes on pseudorabies virus glycoprotein gp50. | 1991 | 1715760 | |
| virus survival in the environment. | viruses pass into the environment from clinically ill or carrier hosts; although they do not replicate outside living animals or people, they are maintained and transported to susceptible hosts. population concentrations and movement, both animal and human, have been steadily increasing in this century, enhancing transmission of respiratory and enteric viruses and compounding the difficulty of preventing environmental transmission. studies on environmental survival factors of viruses have been m ... | 1991 | 1782426 |
| epizootic of pseudorabies among ten swine herds. | an epizootic of pseudorabies in 10 swine herds located near greensburg in decatur county, indiana was investigated. records of decatur county swine herds previously quarantined because of pseudorabies were obtained. for the 1988 epizootic, clinical findings were considered, location of each of the 10 swine herds in relation to the other herds was determined, and potential fomites were considered. meteorologic data prior to, during, and after the epizootic were obtained, correlated, and analyzed. ... | 1991 | 1659567 |
| enzymatic amplification of latent pseudorabies virus nucleic acid sequences. | to investigate various aspects of the latency of pseudorabies virus in swine (prv, suid herpesvirus 1) we developed in vitro nucleic acid amplification methods based upon the polymerase chain reaction. primers flanking a 156-bp region of the pseudorabies virus gp ii gene were annealed to purified prv dna as well as dna isolated from the trigeminal ganglia of swine latently infected with prv and subjected to pcr amplification. following amplification, 100 fg of prv dna was visualizable on stained ... | 1991 | 1659580 |
| immunogenicity in aujeszky's disease virus structural glycoprotein gvi (gp50) in swine. | aujeszky's disease virus (adv) envelope glycoprotein gvi (gp50) was purified from virus-infected vero cells by ion-exchange and immunoaffinity chromatography and its usefulness as a subunit vaccine was evaluated in active and passive immunization studies. four-week-old piglets were immunized intramuscularly (im) with purified gvi twice two weeks apart and challenged intranasally (in) 10 days after the second immunization with 30 ld50 (10(8)pfu) of a virulent strain of adv. pigs, vaccinated with ... | 1991 | 1660638 |
| [aujeszky's disease in swine in the netherlands, a.d. 1991]. | aujeszky's disease is caused by a herpesvirus. the pig is the natural host and sole source of dissemination of the virus. after a primary infection, during which the pig excretes virus for 10-14 days, the virus remains latent in the host. eradication has been achieved in individual herds, areas and countries with a low prevalence. the crucial question is whether it is feasible to eradicate the virus in heavily infected areas. using so-called marker vaccines in conjunction with companion diagnost ... | 1991 | 1661034 |
| sensitivity of the standardized pseudorabies virus neutralization test varies with the test strain used. | the effect of altering the strain of the test virus used in the standardized pseudorabies virus neutralization (vn) test on the sensitivity of the assay was evaluated. comparative vn tests were performed using 4 different strains: the avirulent bartha parental, the avirulent recombinant bartha giiika, the moderately virulent shope (currently used for the vn test at the national veterinary services laboratory, ames, ia), and the highly virulent p2208 (funkhauser). a radioimmunoassay and a western ... | 1991 | 1662079 |
| a comparison of differential diagnostic tests to detect antibodies to pseudorabies glycoproteins gx, gi, and giii in naturally infected feral pigs. | 1991 | 1662082 | |
| evaluation of glycoprotein gii iscoms subunit vaccine for pseudorabies in pig. | one of the pseudorabies virus glycoproteins, gii, was integrated into quil a matrix and formed an antigenic presentation structure known as immunostimulating complexes (iscoms). the gii iscoms protected mice from a lethal infection of pseudorabies virus (prv). subsequently, the efficacy of gii iscoms as a vaccine was evaluated in pigs, a natural host species of prv. immunization of pigs with gii iscoms protected them from prv-induced acute symptoms and death. the serum obtained from immunized pi ... | 1991 | 1659053 |
| virus reactivation in pigs latently infected with a thymidine kinase negative vaccine strain of pseudorabies virus. | attenuated, gene-deletion mutants of pseudorabies virus (prv) were tested for their ability to establish a reactivatable latent infection in pigs. the viruses (designated a, b, and c) were from each of three vaccines commercially available in the united states. viruses a and c were similar in that they had genetically engineered gene deletions for thymidine kinase (tk) and glycoprotein x (gx); however, they had been prepared from genetically different parental strains. virus b was tk positive, b ... | 1991 | 1656920 |
| survival of aujeszky's disease virus in slurry at various temperatures. | survival of aujeszky's disease virus in pig slurry was investigated during anaerobic storage at 5, 20, 35, 40, 45, 50 and 55 degrees c using 100-ml laboratory models simulating the conditions in slurry tanks during winter and summer seasons and during anaerobic digestion in batch reactors. the inactivation rate was found to increase with increasing temperature. virus was inactivated at 5 and 20 degrees c in 15 weeks and 2 weeks, respectively. at 35 degrees c (mesophilic conditions) the virus was ... | 1991 | 1663288 |
| immunohistological demonstration of spread of aujeszky's disease virus via the olfactory pathway in hpcd pigs. | the spread of aujeszky's disease virus (adv) from nasal mucosa via the olfactory pathway was studied in hpcd pigs. adv antigen was detected in the epithelial cells, nasal gland cells, olfactory nerve cells and peripheral nerve fibres in the nasal cavity and in neuroglial cells in the olfactory bulb. results indicate that the olfactory pathway is one of the most important neuronal pathways of adv infection in pigs. | 1991 | 1663956 |
| efficacy of a pseudorabies virus vaccine based on deletion mutant strain 783 that does not express thymidine kinase and glycoprotein i. | the vaccine efficacy of a genetically engineered deletion mutant strain of pseudorabies virus, strain 783, was compared with that of the conventionally attenuated bartha strain. strain 783 has deletions in the genes coding for glycoprotein i and thymidine kinase. in experiment 1, which had a 3-month interval between vaccination and challenge exposure, strain 783 protected pigs significantly (p less than 0.05) better against virulent virus challenge exposure than did the bartha strain. the growth ... | 1991 | 1654033 |
| spread of pseudorabies virus among breeding swine in quarantined herds. | in theory, pseudorabies virus (prv) may be eliminated from any size of breeding herd by phased test and removal if replacement gilts are not infected with prv, culling decisions are partially based on prv status, and the cull rate is higher than the incidence rate of prv. annual cull rates are commonly at least 50%, but little information exists on the incidence of prv within enzootically infected swine herds. the purpose of this study was to develop a method by which spread of prv could be dete ... | 1991 | 1653189 |
| factors associated with the seroprevalence of pseudorabies virus in breeding swine from quarantined herds. | strategies for the elimination of pseudorabies virus (prv) from swine herds include test and removal, offspring segregation, and depopulation/repopulation. the prevalence of prv in a herd is a major factor in selection of the most appropriate strategy. the purpose of the study reported here was to describe the prevalence of prv in adult swine in prv quarantined herds in minnesota, and to determine herd factors associated with the seroprevalence. questionnaires describing the health history of th ... | 1991 | 1664820 |
| the genome type of aujeszky's disease virus isolated from a cat in japan. | 1991 | 1665082 | |
| intranasal vaccination of pigs against aujeszky's disease: protective immunity at 2 weeks, 2 months and 4 months after vaccination in pigs with maternal antibodies. | the purpose of the study was to evaluate the short- and long-term immunity after intranasal vaccination in pigs with maternally derived antibodies (mda). in two experiments, 10-week-old pigs with moderate mda titres against aujeszky's disease virus (adv) were vaccinated intranasally with the bartha strain of adv to evaluate the protective immunity conferred at 2 weeks, 2 months and 4 months after vaccination. protection was evaluated on the basis of severity of clinical signs, periods of fever a ... | 1991 | 1648282 |
| the genomic diversity and stability of field strains of suid herpesvirus 1 (aujeszky's disease virus). | the genomic diversity among isolates of suid herpesvirus 1 (shv-1) collected in the same herd and among clones from the same isolate was studied by restriction fragment pattern (rfp) analysis using bamhi. tentatively defining a field strain as a transmissible entity, it was concluded that strains of shv-1 commonly comprise distinguishable genomic variants. contrary to the hypothesis of genomic lability, it is suggested that the pool of variants is sufficiently stable to specifically characterize ... | 1991 | 1673808 |
| survival of pseudorabies virus in the presence of selected diluents and fomites. | because of the importance of environmental survival of pseudorabies virus to proposals to eradicate the virus from swine in the united states, survival of the virus was studied in various diluents and on combinations of diluents and solid fomites at 25 c. suspensions of the virus in phosphate-buffered saline and saline g solutions remained infectious for at least 10 days. infectivity of other virus/diluent suspensions decreased to less than 10 plaque-forming units/ml in 14 days (swine urine), 7 ... | 1991 | 1648048 |
| effect of various vaccination procedures on shedding, latency, and reactivation of attenuated and virulent pseudorabies virus in swine. | various procedures of vaccination for pseudorabies were compared for their effects on shedding, latency, and reactivation of attenuated and virulent pseudorabies virus. the study included 6 groups: group 1 (10 swine neither vaccinated nor challenge-exposed), group 2 (20 swine not vaccinated, but challenge-exposed), and groups 3 through 6 (10 swine/group, all vaccinated and challenge-exposed). swine were vaccinated with killed virus im (group 3) or intranasally (group 4), or with live virus im (g ... | 1992 | 1466515 |
| skin virulence of attenuated pseudorabies virus (prv) strains. | after intradermal inoculation of the attenuated pseudorabies virus (prv) strains, bartha, mk35 (gi+) and mk35-t-2 (gi-) to rabbits, they caused local inflammatory nodules with oedema reddiness and necrosis. the specifity of these reactions was confirmed by their inhibition with anti-prv serum. the minimal dose that caused visible skin reaction was about 10(2) tcid50/ml for bartha and mk35-t-2 (gi-) strains and over 10(4) tcid50/ml for the mk35 (gi+) strain. it is assumed that the established res ... | 1992 | 1359773 |
| characterization of field isolates of suid herpesvirus 1 (aujeszky's disease virus) as derivatives of attenuated vaccine strains. | field isolates of suid herpesvirus 1 (aujeszky's disease virus) from poland and hungary were identified by restriction fragment pattern analysis as derivatives of attenuated vaccine strains. the polish isolates were found to be related to the buk-tk-900 strain (suivac a) which is widely used as a live vaccine in poland, and the hungarian isolates were related to the bartha k-61 vaccine strain widely used in hungary. pigs experimentally infected with derivatives of buk-tk-900 or buk-tk-900 itself ... | 1992 | 1351387 |
| effects of pseudorabies virus infection upon cytotoxicity and antiviral activities of porcine alveolar macrophages. | alveolar macrophages (am) infected with pseudorabies virus (prv) were compared to noninfected am for cytotoxicity against foreign or transformed cells and production of interferon (ifn). five prv strains were used to infect am including strains that are known to be highly virulent for pigs, i.e. strain 4892 and strain s-62 as well as strains that are regarded as mild or nonvirulent, i.e. buk and bartha. the multiplicity of infection ranged from 0.005 to 0.05 tcid50/cell. the target cells in the ... | 1992 | 1330423 |
| [is aujeszky's disease a zoonosis?]. | several cases of human illness with symptoms suggestive of aujeszky's disease (ad) at an outbreak of the disease in cattle and swine were evaluated during this study. additionally serological studies of people in the group at high risk for illness caused by aujeszky's disease virus (adv) were carried out. in a herd of 180 bulls sudden clinical disease occurred with symptoms of muscular tremors, salivation, sweating and severe pruritus of the head. the clinical disease lasted two to eight hours a ... | 1992 | 1296242 |
| pseudorabies virus envelope glycoproteins gp50 and gii are essential for virus penetration, but only gii is involved in membrane fusion. | to investigate the function of the envelope glycoproteins gp50 and gii of pseudorabies virus in the entry of the virus into cells, we used linker insertion mutagenesis to construct mutant viruses that are unable to express these proteins. in contrast to gd mutants of herpes simplex virus, gp50 mutants, isolated from complementing cells, were able to form plaques on noncomplementing cells. however, progeny virus released from these cells was noninfectious, although the virus was able to adsorb to ... | 1992 | 1309919 |
| latency of a thymidine kinase-negative pseudorabies vaccine virus detected by the polymerase chain reaction. | latent viral dna was detected by the polymerase chain reaction in trigeminal ganglia of all of 10 pigs that were necropsied 81 or more days after they had been infected intranasally with a thymidine kinase-negative (tk-) vaccine strain of pseudorabies virus (prv). failure to reactivate virus from any of the same pigs by earlier treatment with dexamethasone suggested that even though latency can be established with tk- prv, subsequent reactivation may be a relatively rare event. | 1992 | 1309996 |
| chronic morphine administration impairs cell-mediated immune responses in swine. | swine were used as an experimental animal model to evaluate immunomodulating effects of the opiate drug, morphine, on antigen-specific humoral and cell-mediated immune responses. morphine free base in peanut oil was administered at 4-day intervals for up to 42 days to maintain drug levels at or above 100 ng/ml. the effect of morphine administration on humoral immune responses was evaluated by immunization on day 7 of morphine treatment with a battery of antigens, including swine herpes virus (al ... | 1992 | 1310738 |
| characterization of pseudorabies virus antibody responses in young swine after infection and vaccination by using an immunoglobulin m antibody capture enzyme-linked immunosorbent assay. | an immunoglobulin m (igm) antibody capture enzyme-linked immunosorbent assay (macelisa) was developed for the detection of pseudorabies virus (prv)-specific igm antibody in swine sera because false-positive reactions frequently occurred when sera from older swine were tested with an indirect igm enzyme-linked immunosorbent assay. monoclonal mouse anti-swine igm was used as the capturing antibody, and rabbit anti-prv hyperimmune gamma globulin was used as the indicating antibody. sera from non-pr ... | 1992 | 1311334 |
| contribution of single genes within the unique short region of aujeszky's disease virus (suid herpesvirus type 1) to virulence, pathogenesis and immunogenicity. | pigs (3 and 10 weeks old) were infected intranasally with aujeszky's disease virus (adv) mutants that functionally lacked one of the non-essential genes in the unique short region of the genome (except the gene encoding the 11k protein). virus excretion in oropharyngeal fluid and disease symptoms were monitored. some pigs were killed to study pathogenesis, whereas others were challenged with virulent adv 8 weeks after the primary infection. mutants lacking protein kinase, or glycoproteins gp63 o ... | 1992 | 1311354 |
| correlation between gi, gii, giii, and gp 50 antibodies and virus excretion in vaccinated pigs infected with pseudorabies virus. | eleven groups of 8 pigs were vaccinated with different vaccinal strains of pseudorabies virus deleted or not for non-essential glycoproteins (gi, gx, gp 63), then were challenged 8-9 weeks later with a virulent strain. antibodies against the major viral glycoproteins (gii, giii, gp 50) were titrated at the day of challenge. excretion of the challenge strain, growth performance of the pigs, and gi antibody responses from pigs vaccinated with a gi minus strain, were monitored after the challenge. ... | 1992 | 1312820 |
| use of an enzyme-linked immunosorbent assay for detection of infection with pseudorabies virus on a herd basis. | the use of an elisa that can differentiate between swine infected with pseudorabies virus (prv) and swine vaccinated with a specific prv vaccine was evaluated on an individual and herd basis, and a system for interpreting elisa results on a herd basis was developed. in 17 herds, recently introduced replacement gilts, seronegative for prv, were vaccinated with a thymidine kinase- and glycoprotein x (gpx)-deleted vaccine. after vaccination, blood samples were collected from these gilts approximate ... | 1992 | 1313789 |
| stable rescue of a glycoprotein gii deletion mutant of pseudorabies virus by glycoprotein gi of bovine herpesvirus 1. | glycoproteins homologous to glycoprotein b (gb) of herpes simplex virus constitute the most highly conserved group of herpesvirus glycoproteins. this strong conservation of amino acid sequences might be indicative of a common functional role. indeed, gb homologs have been implicated in the processes of viral entry and virus-mediated cell-cell fusion. recently, we showed that pseudorabies virus (prv) lacking the essential gb-homologous glycoprotein gii could be propagated on a cell line expressin ... | 1992 | 1313900 |
| identification and characterization of pseudorabies virus glycoprotein h. | on the basis of dna sequence analysis, it has recently been shown that the pseudorabies virus (prv) genome encodes a protein homologous to glycoprotein h (gh) of other herpesviruses (b. klupp and t.c. mettenleiter, virology 182:732-741, 1991). to obtain antibodies specific for gh(prv), rabbits were immunized with synthetic peptides representing two potential epitopes on gh(prv) as predicted by computer analysis. the antipeptide sera recognized the gh precursor polypeptide pgh translated in vitro ... | 1992 | 1313917 |
| a murine model of pseudorabies virus latency. | the mouse is a useful laboratory animal for studying various aspects of pseudorabies virus (prv) virulence. mice are highly susceptible hosts for prv infection and are unable to survive acute viral infection. because of this, mouse models have not been useful for studying prv latent infections. here, we report an efficient strategy for establishing latent prv infections in laboratory mice. passive transfer of high titered neutralizing antibodies to mice prior to inoculation with highly lethal do ... | 1992 | 1313942 |
| [comparison of antibody titers against aujeszky's disease virus in pig blood collected on the farm and in the slaughterhouse]. | antibody titres against aujeszky's disease virus (adv) in the plasma of slaughter pigs were compared with respect to the site of sampling, namely on the farm (one day before delivery to the slaughterhouse) and in the slaughterhouse during slaughter. no significant differences were noted in the antibody titres against adv with respect to the different sampling sites. blood samples collected at the slaughterhouse can be used for monitoring and surveillance systems within the framework of organised ... | 1992 | 1313993 |
| high- and low-challenge exposure doses used to compare intranasal and intramuscular administration of pseudorabies virus vaccine in passively immune pigs. | we compared 3 modified-live pseudorabies virus (prv) vaccine strains, administered by the intranasal (in) or im routes to 4- to 6-week-old pigs, to determine the effect of high- and low-challenge doses in these vaccinated pigs. at the time of vaccination, all pigs had passively acquired antibodies to prv. four experiments were conducted. four weeks after vaccination, pigs were challenge-exposed in with virulent virus strain iowa s62. in experiments 1 and 2, a high challenge exposure dose (10(5.3 ... | 1992 | 1314793 |
| measurement of isotype-specific antibody responses to aujeszky's disease virus in sera and mucosal secretions of pigs. | enzyme-linked immunosorbent assays (elisas) for the detection of porcine igm, iga, igg1 and igg2 antibodies directed against aujeszky's disease virus (adv) are described. adv-specific iga and igm were detected in an antibody capture assay, and adv-specific igg1 and igg2 were detected in an indirect double antibody sandwich assay. a selected set of samples was tested in the four elisas and in a 24 h virus neutralization assay. comparison of the results showed that the elisas were isotype-specific ... | 1992 | 1315087 |
| field experiments to evaluate the feasibility of eradication of aujeszky's disease virus by different vaccination schedules. | in the present report, the extent of the reduction in aujeszky's disease virus (adv) dissemination achieved when pigs were intensively vaccinated with gi-deleted vaccines under field circumstances, was examined. on widely dispersed breeding-fattening farms, a gi-negative status was most rapidly obtained and the rate of new waves of infections was lowest when the attenuated bartha strain was administered to both the sows and the fatteners. it was more difficult not only to reach but also to keep ... | 1992 | 1315465 |
| variation in seropositivity for some respiratory disease agents in finishing pigs: epidemiological studies on some health parameters and farm and management conditions in the herds. | the relationship between the extent of seropositivity for aujeszky's disease virus (adv), actinobacillus pleuropneumoniae (app.) serotype 2 and porcine influenza (pi) viruses serotype h1n1 and h3n2 in pigs on the one hand and the health status of the pigs and some farm and management conditions in the herds on the other hand was studied in 45 pig finishing herds, all members of one integration group. the health status was assessed by the extent of clinical signs, the use of veterinary drugs and ... | 1992 | 1315466 |
| protection of mice and swine from pseudorabies virus conferred by vaccinia virus-based recombinants. | glycoproteins gp50, gii, and giii of pseudorabies virus (prv) were expressed either individually or in combination by vaccinia virus recombinants. in vitro analysis by immunoprecipitation and immunofluorescence demonstrated the expression of a gii protein of approximately 120 kda that was proteolytically processed to the giib (67- to 74-kda) and giic (58-kda) mature protein species similar to those observed in prv-infected cells. additionally, the proper expression of the 90-kda giii and 50-kda ... | 1992 | 1316458 |
| air sampling procedure for evaluation of viral excretion level by vaccinated pigs infected with aujeszky's disease (pseudorabies) virus. | five groups of eight fattening pigs were vaccinated and then infected with aujeszky's disease virus. viral excretion was evaluated by two means: deep nasal swabbing and air sampling. it appeared that infectious airborne virus could be recovered from day 1 to day 6 after infection in the isolated units where control animals were raised. in vaccinated animals, airborne particles were also detected but the amount and duration varied in relation to their immune status at the day of virulent challeng ... | 1992 | 1316629 |
| abortion induced by cell-associated pseudorabies virus in vaccinated sows. | pregnant sows, immune against pseudorabies after vaccination, were inoculated at 70 days of gestation either with autologous blood mononuclear cells that had been infected in vitro with pseudorabies virus (prv) or with cell-free prv. the infected cells or cell-free prv were inoculated surgically into the arteria uterina. eight sows (a to h) had been vaccinated with an inactivated vaccine. the titer of seroneutralizing antibodies in their serum varied between 12 and 48. five sows (a to e) were in ... | 1992 | 1316724 |
| study of the potential involvement of pseudorabies virus in swine respiratory disease. | in order to investigate the potential involvement of pseudorabies virus (prv) in swine respiratory disease, nine week old pigs were intranasally inoculated with the prv strain 4892. two doses of infection were used: 10(4.5) median tissue culture infectious doses (tcid50)/pig and 10(3.5) tcid50/pig, with ten pigs per group. in the group of pigs inoculated with 10(4.5) tcid50, seven out of ten pigs died within six days after inoculation. the mortality rate in the group of pigs inoculated with the ... | 1992 | 1316799 |
| replication and immunosuppressive effects of pseudorabies virus on swine peripheral blood mononuclear cells. | the infectivity and potential immunosuppressive effects of pseudorabies virus (prv) was evaluated in swine peripheral blood mononuclear cells (pbmc). virus progeny titers and viral dna synthesis at various intervals post-inoculation revealed the replication of prv in both peripheral blood monocytes and lymphocytes; however, replication in lymphocytes was restricted compared with monocytes. prv infection resulted in the damage and death of monocytes. although prv did not appear to affect the viab ... | 1992 | 1317617 |
| inoculation of pigs with streptococcus suis type 2 alone or in combination with pseudorabies virus. | pigs (9 [+/- 1] weeks old) were inoculated with streptococcus suis type 2, pseudorabies virus (prv), or both. for each pig of groups a, b, and c the inoculum of s suis was 10(9) colony-forming units. for each pig of groups a, b, and d the inoculum of prv was 5 x 10(3) tcid50 of either prv strain 4892 (group a, n = 9) or prv isolate b (group b, n = 9). the prv strain 4892 is a highly virulent strain; isolate b causes mild clinical signs of infection in inoculated pigs. group-c pigs (n = 9) were g ... | 1992 | 1317689 |
| comparative efficacy of three doses of the genetically engineered aujeszky's disease virus vaccine strain 783 in pigs with maternal antibodies. | pigs with low levels of maternally derived antibodies were vaccinated twice intramuscularly with 10(5), 10(5.5), or 10(6) plaque forming units (p.f.u.) of the genetically engineered aujeszky's disease virus (adv) vaccine strain 783. strain 783 has deletions in genes encoding glycoprotein gi and thymidine kinase. all vaccinated pigs showed a high level of protection against clinical disease after challenge infection with virulent adv. vaccination also reduced virus excretion. the daily mean virus ... | 1992 | 1317982 |
| detection of pseudorabies virus infection in subunit-vaccinated and nonvaccinated pigs using a nucleocapsid-based enzyme-linked immunosorbent assay. | the potential of a pseudorabies virus (prv) nucleocapsid protein (nc)-based enzyme-linked immunosorbent assay (elisa) as a screening assay for prv infection in subunit-vaccinated and nonvaccinated pigs was studied. the nc-elisa compared favorably to a commercial elisa for detecting prv infection in nonvaccinated pigs. virus-specific antibody was first detected by the nc-elisa between days 14 and 21 in 5 pigs challenged intranasally with 10(4) pfu of virus. antibody continued to be detected in th ... | 1992 | 1319749 |
| comparison of virus isolation, immunofluorescence and dna probe hybridization for detection of pseudorabies virus in experimentally infected pigs. | virus isolation, immunofluorescent staining and dna probe hybridization, three techniques for the detection of pseudorabies virus (prv) have been compared in pigs experimentally infected with the thailand cb-1 strain prv. the virus isolation and dna hybridization detection demonstrated a good correlation in detecting infection in live animals by nasal swabbing. in white blood cells an earlier detection was seen with the dna-hybridization techniques. consistent results with all the three techniqu ... | 1992 | 1320311 |
| pseudorabies virus glycoprotein iii derived from virions and infected cells binds to the third component of complement. | glycoprotein iii (giii) of pseudorabies virus (prv) was shown to bind to the third component of complement (c3). this was observed only with porcine c3 whereas human c3 showed negligible binding under the conditions tested. prv virion proteins could be precipitated from supernatants and cell lysates of prv-infected cells by means of swine-c3 coupled to sepharose. according to their molecular size and their reactivity with anti-giii monoclonal antibodies, the precipitated prv proteins represented ... | 1992 | 1320797 |
| genotypic screening of pseudorabies virus strains for thymidine kinase deletions by use of the polymerase chain reaction. | genetic recombination between field strains and vaccine strains of pseudorabies virus (prv) has been suggested as a scenario that might arise from use of deletion-mutant modified-live vaccine strains, particularly those strains attenuated by deletions within the thymidine kinase (tk-) gene locus. to address this hypothesis experimentally, it is necessary to screen large numbers of prv isolates for their tk genotype. techniques to detect the native tk genotype are routinely used in molecular viro ... | 1992 | 1320813 |
| characterization of japanese isolates of aujeszky's disease virus by restriction endonuclease cleavage patterns, virulence in mice and thymidine kinase activity. | twenty four cloned isolates of aujeszky's disease virus collected from outbreaks of aujeszky's disease from 1981 through 1989 in japan were characterized by their restriction endonuclease (re) cleavage patterns, virulence for mice and thymidine kinase (tk) activity. all of the isolates belonged to type ii of the four types classified by herrmann et al. (1984). based on the number and migration rate of the restriction fragments, the isolates were divided into 7 groups with bam hi, 9 groups with k ... | 1992 | 1322716 |
| differential polymerase chain reaction for detection of wild-type and a vaccine strain of aujeszky's disease (pseudorabies) virus. | a polymerase chain reaction (pcr) strategy for differentiating between a vaccine mutant strain and wild-type (wt) strains of aujesky's disease (pseudorabies) virus (adv) was evaluated. with this approach, a single virus or a concurrent wt and vaccine virus infection could be distinguished by targeting the genomic alteration within the vaccine strain. pcr primers were designed for a recombinant vaccine virus that has almost all of the wt gx gene replaced by the lacz gene. one primer, correspondin ... | 1992 | 1322928 |
| viral susceptibility of an established cell line of swine embryo kidney. | the viral susceptibility of a cell line, named ksek6, newly established from the kidney cortex of swine embryo was tested for the indication of cpe occurrences and also plaque formations. the multiplication of porcine adenoviruses was considerably high in the cells among the virus strains tested though plaques of these viruses were hardly visible under agar overlay medium. two strains of swine enteroviruses, aujeszky's disease virus and hemagglutinating encephalomyelitis virus also multiplied we ... | 1992 | 1323743 |
| evaluation of the sensitivity and specificity of two diagnostic tests for antibodies to pseudorabies virus glycoprotein x. | the diagnostic performance of 2 enzyme-linked immunosorbent assays (gx-t, gx-h) for antibodies to pseudorabies virus (prv) glycoprotein x (gx) were evaluated using 311 serum samples from a nonvaccinated quarantined herd. when the standardized virus neutralization (vn) test, which uses the shope strain (vn shope), was used as the comparative diagnostic standard, the gx-t test had a 7% false-negative rate and a 52% false-positive rate, and the gx-h test had a 19% false-negative rate and a 19% fals ... | 1992 | 1325190 |
| simplified characterization of pseudorabies viruses using monoclonal antibody and selective cell culture analyses. | 1992 | 1325194 | |
| influence of vaccination route on the efficacy of aujeszky's disease deletion-mutant vaccine. | in order to compare the effect of the route of immunization on the efficacy of a modified live aujeszky's disease (ad) vaccine, which had deletions in both thymidine kinase (tk-) and glycoprotein giii genes (gpiii-), 20 six-week-old pigs were vaccinated by either the intramuscular (im) (n = 10) or subcutaneous (sc) (n = 10) route. all the animals, including five non-vaccinated control animals, were challenged with virulent ad virus 22 days after vaccination. four of five non-vaccinated animals d ... | 1992 | 1327180 |
| interaction of pseudorabies virus with porcine peripheral blood lymphocytes. | to examine effects of pseudorabies virus (prv) on immune cells, we investigated the ability of prv to infect and replicate in porcine peripheral blood leukocytes (pbls). flow cytometric analysis revealed a leukopenia after challenge, with loss of 40% of circulating monocytes and 50% of circulating lymphocytes. virus was isolated from pbls of challenged pigs by cocultivation with porcine kidney cells, indicating that pbls were infected in vivo. presence of virus in pbls coincided with the appeara ... | 1992 | 1328444 |
| [practice observations of cross protection between bovine and porcine herpesviruses]. | in many cattle herds in lower saxony the serologic ibr/ipv = bhv-1-status is known because since 1988 the bovine herpes virus infection (bhv 1), the infectious rhinotracheitis and pustular vulvovaginitis (ibr/ipv) are being fought. through extensive investigations in five districts in the weser-ems area, it was found that cows infected by bovine herpes virus (bhv 1) are also protected to a high degree against infection by porcine herpes suis virus (shv 1). an interpretation of the observed cross ... | 1992 | 1332217 |
| comparison of three glycoprotein-i elisas for aujeszky's disease virus. | 1992 | 1332240 | |
| evaluation of two elisa kits for the detection of aujeszky's disease antibodies in pigs. | this work describes the evaluation of two commercial elisa kits for the detection of gi antibodies against aujeszky's disease. a collection of experimental sera from infected pigs, field sample sera, and sera from pigs vaccinated with seven different modified gi-negative commercial vaccines were used to evaluate each test. both elisa kits showed good reproducibility, and specificity, but differences could be appreciated in sensitivity when sera obtained at early stages of infection was analysed. ... | 1992 | 1333666 |
| antigens involved in vaccination of swine against aujeszky's disease (pseudorabies) virus. | the polypeptide and glycopolypeptide composition of a local virulent aujeszky's disease virus (suid herpesvirus 1, shv-1) strain (e-974) was determined in order to characterize the individual shv-1 antigens inducing the serological responses in immunized and non-immunized animals. a commercially available inactivated vaccine of known efficacy and three experimental immunogen preparations (whole inactivated shv-1 particles, lectin-purified glycoproteins from shv-1 culture, and a combination of bo ... | 1992 | 1333691 |
| [use of an immunoenzyme histochemical method for the improvement of the etiologic diagnosis of aujeszky's disease in swine]. | with regard to the legal regulations for the diagnosis of aujeszky's disease in pigs, a retrospective immunoenzymatic study was performed on brains of 20 pigs, in which aujeszky's disease had been diagnosed based only on clinical, macroscopical and histological findings, although the etiological agent could not be demonstrated neither by immunofluorescent technique nor by virological cultivation. applying the peroxidase-antiperoxidase-(pap) method, in 6 of 20 animals (30%) viral antigen of porci ... | 1992 | 1335229 |
| pseudorabies (aujeszky's disease) in argentina. | various methods have been employed for the diagnosis of pseudorabies in argentina. a large serological survey was carried out by means of enzyme-linked immunosorbent assay (blocking elisa) and virus neutralisation (vn). an outbreak was studied by virological and immunohistochemical methods and in situ nucleic acid hybridisation. | 1992 | 1335307 |
| adjuvant properties of propionibacterium avidum kp-40 in vaccination against endemic viral and bacterial infections. i. swine immunized with live attenuated aujeszky's disease virus vaccine and experimentally infected with virulent viruses. | forty 5-month old swine were treated with immunomodulating propionibacterium avidum kp-40 (pa) and/or immunized with live attenuated aujeszky's disease (ad) virus vaccine (suivaca); 8 weeks later all animals were infected with virulent ad viruses (nia-3). seven of 10 swine vaccinated without pa developed mild/moderate symptoms of infection with 3- to 5-day fever and a temporary halt in weight gain. application of pa together with the vaccine lowered the morbidity rate, shortened the period of fe ... | 1992 | 1338942 |
| haematological and clinicochemical blood profiles in slaughter pigs. | in a cohort study, 40 pig finishing herds were selected: twenty pig herds with a low and twenty pig herds with a high prevalence of several pathological lesions recorded at slaughter in a six-month period before the start of the study. blood samples were taken from 20 pigs per herd at the end of the finishing period to investigate haematological and clinicochemical profiles. there was only a significant difference in serum albumin concentration between the low and high lesion prevalence groups. ... | 1992 | 1380195 |
| 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 ... | 1992 | 1446274 |
| immunopathology in aujeszky's disease virus-infected pigs exposed to fluctuating temperatures. | pigs exposed to fluctuating temperatures (high, 30 +/- 2 degrees c; low, 4 +/- 1 degrees c) were intranasally inoculated with aujeszky's disease virus (adv). adv-infected pigs, exposed to the fluctuating temperatures, showed severe clinical signs and adv in the nasal secretions persisted longer than in the adv-infected control pigs kept at the normal temperature (20 +/- 2 degrees c). high concentrations of adv were isolated from nasal secretions on the 1st day after inoculation of the virus. pat ... | 1992 | 1452815 |
| economic impact of an epizootic of pseudorabies in a commercial swine herd in ohio, achieving test negative status and quarantine release by use of vaccination and test and removal. | the effect of pseudorabies in a commercial farrow-to-finish operation on selected production and economic values was estimated. pseudorabies was first diagnosed in this herd by circle testing done in march 1988, as a required part of follow up from another herd that had been diagnosed with pseudorabies in the area. a pseudorabies virus vaccination program was initiated in the herd at that time. the mean litter size of pigs born alive varied from 9.26 to 10.02 pigs/litter throughout the study per ... | 1992 | 1639683 |
| molecular cloning of a gene encoding porcine interferon-beta. | a gene encoding the porcine interferon-beta (poifn-beta) was cloned from a genomic library. the sequence of a potential intronless coding region as well as 1,265 bp of the 5'- and 277 bp of the 3'-flanking regions is presented. the gene is predicted to encode a mature protein of 165 amino acids and a signal peptide of 21 amino acids. this probable poifn-beta shows high homology (63%) with human (hu) ifn-beta at the amino acid level, but less with porcine (po) ifn-alpha 1 (32%). it contains three ... | 1992 | 1640116 |
| multiplication and immunogenicity of a temperature-sensitive and thymidine kinase-deficient strain of aujeszky's disease virus in pigs. | hysterectomy-produced colostrum-deprived 5- and 27-day-old pigs were inoculated intramuscularly (im) or intranasally (in) with the temperature-sensitive and thymidine kinase-deficient zhtstk- strain of aujeszky's disease virus (adv), and the nasal swabs and organs of the pigs were periodically collected for virus isolation. no abnormal clinical signs were observed in these pigs, except for a mild febrile response. viral shedding in the nasal swabs with low titers was detected in the pigs inocula ... | 1992 | 1335758 |
| role of memory b-cell responses in serum and mucosal fluids of swine for protective immunity against pseudorabies virus. | we examined primary and memory isotype-specific antibody responses directed against pseudorabies virus in serum and mucosal fluids of pigs with and without passively acquired maternal antibody, and we studied the relationship between these responses and protection against virus challenge. pigs were inoculated intranasally with the virulent nia-3 strain or the avirulent bartha strain, or they were inoculated im with an inactivated vaccine containing the phylaxia strain. ten weeks later, all pigs ... | 1992 | 1334639 |
| molecular analysis of pseudorabies viral vaccines and their rapid differentiation from wild-type isolates using dna-amplified glycoprotein i and thymidine kinase gene segment polymorphisms. | several conventional and genetically recombinant modified-live viral (mlv) vaccines are used to control pseudorabies virus infections (aujeszky's disease, prv) in swine. differentiating vaccinal prv (v-prv) from wild prv (wt-prv) is important for herd health, regulatory and forensic purposes, and for studies of prv latency and epidemiology. all prv vaccines used currently contain glycoprotein i (gi) and/or thymidine kinase (tk) gene deletions, whereas wt-prv typically contain intact gi and tk ge ... | 1992 | 1333775 |
| the pseudorabies virus homology of the herpes simplex virus ul21 gene product is a capsid protein which is involved in capsid maturation. | we mutagenized, mapped, and sequenced the pseudorabies virus (prv) homology of gene ul21 of herpes simplex virus type 1. a polyclonal mouse antiserum against the protein encoded by the ul21 homolog was generated and used to monitor the expression and subcellular localization of the ul21-encoded protein. we found that the protein is identical to a previously detected prv capsid protein. we analyzed viable prv strains encoding mutant ul21 homologys, truncated by insertion of an oligonucleotide tha ... | 1992 | 1331512 |
| [vaccination of sheep against aujeszky's disease with a gi-deleted mutant]. | the use of gl deleted live vaccines against aujeszky's disease (ad) facilitates to differentiate vaccinated from field-virus infected animals. in this study different modes of vaccination were tried to find out how sheep can be protected from a lethal infection with adv. it could clearly be demonstrated that aujeszky disease virus (adv) is spread by horizontal transmission from infected pigs to sheep. the nasal discharges of infected pigs contained a maximum of 10(8.75)tcid50/g mucus at days 3 a ... | 1992 | 1330479 |
| [experimental infection of pregnant gilts with aujeszky's disease virus strain rc/79]. | the rc/79 strain of the aujeszky's disease virus was able to induce reproductive failure of pregnant gilts intranasally inoculated at different gestation periods. four gilts 40-46 days pregnant (group a) and 6 gilts 70-73 days pregnant (group b) were instilled with 0.2 ml x 10(5) tissue culture infectious dose 50 (tcid50/0.2 ml) of the rc/79 strain into each nostril. two gilts 70-73 days pregnant (group c) were used as non exposed controls. the three groups were kept in separated boxes and they ... | 1992 | 1338479 |
| replication of the pseudorabies virus in cultured pancreatic islet cells: further evidence of their paraneuronal nature. | pancreatic b cells are known to be damaged by a wide range of viruses, causing diabetes. though these viruses belong to different taxonomic groups, their single shared characteristic is neurotropism. in the present study, pseudorabies viral infection was modelled on fetal porcine islets cultivated in vitro. it was demonstrated that the endocrine cells of the pancreas, especially b cells, were infected in vitro and so served as a medium for the replication of the virus. all stages of the morphoge ... | 1992 | 1338285 |
| acceptability of aujeszky's disease vaccines. | vaccines against aujeszky's disease are not only used to prevent the clinical consequences of a field infection, but also to support eradication of the virus. the current aujeszky's disease vaccines (adv) protect against severe clinical signs of disease and they reduce but usually do not prevent virus multiplication and excretion or the establishment of latency after infection. vaccines also limit virus multiplication after reactivation. the efficacy of vaccination is reduced by passively acquir ... | 1992 | 1337526 |
| role of different genes in the virulence and pathogenesis of aujeszky's disease virus. | in this study the role of different genes located in the unique short region of the genome of aujeszky's disease virus was examined. inactivation of the genes encoding the protein kinase (pk), gp63, and gi reduced virulence of the virus for pigs, in contrast to inactivation of the genes encoding the 28 kda protein, and gx. there was no correlation between virulence and virus multiplication in vitro or in the oropharynx in vivo. the morphogenesis of the pk mutant was altered. the gi mutant replic ... | 1992 | 1336250 |
| analysis of glycoprotein i (gi) negative and aberrant pseudorabies viral diagnostic isolates. | glycoprotein i (gi) phenotypes and genotypes of 4 pseudorabies viral diagnostic isolates were evaluated by use of in vitro dna amplification, monoclonal antibody binding, gi-specific serodiagnostic responses, and in vivo virulence approaches. three viruses were avirulent and did not elicit gi-specific serologic responses, react with gi-specific monoclonal antibodies, or contain gi epitope-encoding dna sequences. the fourth virus was virulent and did elicit a gi-specific serodiagnostic response. ... | 1992 | 1335706 |
| applications of insect cell gene expression in pharmaceutical research. | 1993 | 7764046 | |
| rapid cold fixation of tissue samples by microwave irradiation for use in electron microscopy. | a cold microwave irradiation procedure was developed to fix rapidly and stain various tissues and monolayers for electron microscopy. because microwave stimulation always produces some heat, melting ice was used to maintain the temperature of the tissue samples, the fixative, and the staining solution at 0 to 4 degrees c. the low temperature also reduced vapour formation, thus minimizing the risk of explosion. the microwave method shortened the total time of fixation and dehydration from the usu ... | 1993 | 7506702 |
| pneumonia in pigs inoculated with pseudorabies virus by means of a bronchoscope. | pigs inoculated endobronchially (eb) with 2 ml of virus suspension containing 10(4) tcid50 per ml of the ys-81 strain of pseudorabies virus (prv), by means of a bronchoscope, all developed viral pneumonia. no pneumonic lesions were observed in intranasally inoculated pigs. macroscopical and microscopical lesions were localized to the middle to caudal parts of the right caudal lobe and were closely associated with the site at which the inoculum was deposited. prv became attached to all types of c ... | 1993 | 8106666 |
| use of colostrum to detect antibodies against glycoprotein i of aujeszky's disease virus. | serum and colostrum samples taken from 499 sows from five herds of pigs endemically infected and vaccinated against aujeszky's disease virus, were used to investigate whether colostrum could be used to detect antibodies against glycoprotein i (gi) of the virus. using serum as the reference, the test applied to colostrum had a sensitivity of 97 per cent and a specificity of 88 per cent. when samples were taken from 50 sows from a gi seronegative vaccinated herd, one colostrum sample was gi-positi ... | 1993 | 8116169 |
| mechanism of pruritus and peracute death in mice induced by pseudorabies virus (prv) infection. | mechanisms of postinfectious pruritus and peracute death in mice by pseudorabies virus (prv) were investigated by inoculating the yamagata-s81 strain of prv peripherally or intracerebrally into 4-week-old icr and balb/c mice. clinical signs developed most rapidly in mice inoculated intracerebrally, with intermediate speed in mice inoculated intraocularly, and slowly in mice inoculated subcutaneously. since intraocularly inoculated mice showed an acute reaction and this is considered a peripheral ... | 1993 | 8117815 |
| further evidence of long distance airborne transmission of aujeszky's disease (pseudorabies) virus. | in spite of the eradication of aujeszky's disease in denmark a single outbreak was recorded in december 1988 and another severe epizootic took place during the winter and spring of 1989/90. the epizootic occurred in nearly the same areas as the preceding epizootic during the winter of 1987/88. identification of the strains of virus involved eliminated the possibility that the latest epizootic was due to the persistence of virus in the pig population. furthermore, as during the preceding epizooti ... | 1993 | 8097603 |
| high frequency intergenomic recombination of suid herpesvirus 1 (shv-1, aujeszky's disease virus). | examples are given of observations made with field isolates of suid herpesvirus 1 (shv-1) which indicate that intergenomic recombination is a common phenomenon associated with the virus. this was further confirmed by experimental co-infection of a pig with 2 virus strains with different, stable and easily identifiable genomic markers, followed by natural transmission to a group of contact pigs. a variety of recombinants was subsequently isolated, while none of the parental strains were re-isolat ... | 1993 | 8102524 |
| [the effect of 3 times per year random vaccination of sows against aujeszky's disease on maternal immunity in a breeding farm]. | research was undertaken to study the effect of a 'three times a year vaccination schedule in sows' against aujeszky's disease (ad) on the maternal immunity of their offspring at a large pig farm. only gi-negative sows and piglets were induced in the study. the maternal immunity was measured in the 8-week-old offspring of 6 gilts and 13 sows, vaccinated in early pregnancy and in 8-week-old piglets born from 12 gilts and 21 sows vaccinated 3 weeks prior to farrowing. at an age of 8 weeks only 5 pe ... | 1993 | 8266305 |
| circumvention of maternal antibody interference by immunization of newborn pigs with glycoprotein giii-deleted marker vaccine. | maternal antibodies interfere with the immunization of swine by modified live-virus pseudorabies virus (prv) vaccines. to test the hypothesis that a prv vaccine attenuated by deletions in the thymidine kinase (tk) and giii genes might reduce interference by maternal antibodies, pigs with moderate to low levels of colostral prv antibodies were immunized with the tk- giii-omnimark-prv vaccine. vaccinates and non-vaccinates were challenged intranasally with virulent prv at 7 weeks of age. in suppor ... | 1993 | 8270271 |
| comparison of in vivo reactivation, in vitro reactivation, and polymerase chain reaction for detection of latent pseudorabies virus infection in swine. | the following methods were compared for their ability to detect latent pseudorabies virus in 24 pigs that had been experimentally infected with virulent pseudorabies virus: 1) in vivo reactivation by dexamethasone administration, 2) in vitro reactivation by 5 different techniques of explant culture or cocultivation of trigeminal ganglia, and 3) detection of pseudorabies virus genome in tissue digests of tonsils or trigeminal ganglia using the polymerase chain reaction. reactivation of pseudorabi ... | 1993 | 8286446 |
| evaluation of serological pseudorabies tests for the detection of antibodies during early infection. | six enzyme-linked immunosorbent assays, a latex agglutination test, and the standard microtitration serum virus neutralization test were compared for their ability to detect antibodies against pseudorabies virus (prv) during the early stages of infection. thirty-five pigs were infected intranasally with 10(5)-10(7) tcid50 of either the iowa 4892 pneumotropic or the becker strain of prv. blood samples were drawn from experimentally inoculated animals on days 4-10, 14, and 21 postchallenge. test s ... | 1993 | 8286450 |
| distinction between aujeszky's disease virus-infected and vaccinated pigs by hemagglutination-inhibition test. | a hemagglutination-inhibition (hi) test was applied to distinguish virulent aujeszky's disease virus infected pigs from those immunized with a glycoprotein giii deletion vaccine. the vaccine strain, dlg92/dltk, did not have hemagglutination activity with mouse erythrocytes and the pigs vaccinated five times with the dlg92/dltk strain failed to develop hi antibody, although they developed neutralizing antibody with 128 to 512 titers to aujeszky's disease virus. on the other hand, these pigs produ ... | 1993 | 8286546 |
| rapid identification and quantitation of cells infected by recombinant herpesvirus (pseudorabies virus) using a fluorescence-based beta-galactosidase assay and flow cytometry. | we recently described construction and use of a beta-galactosidase expression cassette in isolating recombinant pseudorabies virus (prv) mutants (mettenleiter and rauh, 1990). we report here the identification and exact quantitation of cells infected by these mutants using an assay based on the reaction of intracellular beta-galactosidase expressed during infection by the recombinant viruses with the fluorogenic substrate fluorescein di-beta-d-galactopyranoside (fdg) followed by detection of pos ... | 1993 | 8227283 |