the influence of ph on the growth and stability of transmissible gastroenteritis virus in vitro.the influence of ph on the growth of transmissible gastroenteritis virus (tgev) in adult pig thyroid cell culture, and on the stability of the virus was studied. at ph 7.2 and 100 fold higher than those at ph 8.0. the adsorption, penetration and uncoating steps of the viral replicative cycle were shown to be unaffected by ph variation. synthesis of tgev rna during the first 12 hours post infection was found to be unaffected by ph variation between the range 6.5-8.0. after 12 hours breakdown of t ...19752142
in vitro differentiation and ph sensitivity of field and cell culture-attentuated strains of transmissible gastroenteritis virus.characteristics of four transmissible gastroenteritis (tge) virus field strains (miller, purdue, bl, and v203) and four cell culture-attenuated strains (purdue, sh, ckp, and bl) were studied to find methods of differentiation between the two groups of viruses. tge field virus strains did not replicate as well as attenuated strains at 37 c and could not be passaged serially for more than four to six passages at 33 c. there were clear differences in plaque size when the strains were compared. fiel ...19769360
effect of precipitation with methanol on antigenic potency of tge virus. 1975167507
identification of heat-dissociable rna complexes in two porcine coronaviruses. 1975170536
vaccination experiments against transmissible gastroenteritis (tge) of swine. iii. the virus-neutralizing titre of vaccinated sows' milk and its persistence during the lactation period. 1975171935
vaccination experiments against transmissible gastroenteritis (tge) of swine. iv. the titre and persistence of virus-neutralizing antibodies in the sera of sows vaccinated once or twice at different intervals. 1975171936
[use of the direct immunofluorescence method for determination of the tge viral antigen in swine].followed up were the appearance and accumulation of the transmissive gastroenteritis (tge) virus antigen in infected cells of pig kidney and thyroid. used were specific conjugates, such introduced by the authors and some imported from czechoslovakia. the cell cultures were infected with strains of the tge virus, isolated in bulgaria or supplied from czechoslovakia. it was found that the bulgarian strains were the same as those from czechoslovakia and the united states. a viral antigen was found ...1975174279
[transmissible gastroenteritis in swine (author's transl)].transmissible gastroenteritis or tge is a virus diarrhoea which occurs in pigs of all ages and is associated with high mortality rates in the young piglets. growth of virus in the columnar epithelium of the small intestine causes atrophy of the intestinal villi, malabsorption, watery diarrhoea and dehydration. faecal excretion of virus usually continues up to fourteen days after infection but chronic carriers have been found to occur. tge is self-limiting on the majority of pig-breeding farms bu ...1976175523
[viral gastroenteritis in swine]. 1975175547
[epizootiology of viral (transmissible) gastroenteritis of swine]. 1976176769
effect of ambient temperatures on multiplication of attenuated transmissible gastroenteritis virus in the bodies of newborn piglets.newborn piglets were found to be more resistant to infection with attenuated transmissible gastroenteritis virus when maintained at higher temperatures. this was attributed to a decreased rate of virus propagation and spreading in the bodies of the infected animals. the highest virus levels were detected in the tissues of piglets maintained at 8 to 12 c. in contrast, no virus was recovered from piglets maintained at 35 to 37.5 c. the virus was found only in the lymph nodes and respiratory organs ...1976178601
chromatographic separation of gram quantities of immunoglobulins from porcine colostrium against transmissible gastroenteritis virus.similar immunoglobulin (ig) classes were obtained from porcine colodtral whey by either column or batch chromatographic procedures; a stepwise buffer elution technique was used. specific transmissible gastroenteritis virus neutralizing antibody was found in the 4 major fractions eluted comprising of igg1, igg2, iga, and igm. the igg1, and igg2 were essentially homogeneous, and the iga- and igm-rich fractions had to be recycled several times through sephadex g-200 to obtain pure iga and igm that ...1976180183
antibody response in pigs inoculated with transmissible gastroenteritis virus and cross reactions among ten isolates.groups of two or three day old pigs were inoculated intravenously with cell culture grown transmissible gastroenteritis virus. a single or a multiple dosage schedule was used. the magnitude of immune response was measured in terms of serum neutralization indices. a single dose of relatively attenuated virus caused mild clinical signs of transmissible gastroenteritis infection in the pigs and induced a low level of antibody in the serum by the seventh day after inoculation. repeated injections of ...1976187297
transmissible gastroenteritis virus: plaques and a plaque neutralization test.a plaquing system and plaque neutralization test in porcine thyroid cells were used to study different transmissible gastroenteritis isolates and hemagglutinating encephalomyelitis virus. among transmissible gastroenteritis virus isolates, plaque size varied considerably and mixed size ranges sometimes occurred. the most recently isolated viruses produced smaller plaques than the laboratory viruses or hemagglutinating encephalomyelitis virus. all transmissible gastroenteritis virus isolates reac ...1976187296
the detection of transmissible gastroenteritis viral antibodies by immunodiffusion.precipitating antibodies against transmissible gastroenteritis viral antigens were detected by the immunodiffusion test in two transmissible gastroenteritis viral hyperimmune antisera and in antiserum prepared against haemagglutinating encephalomyelitis virus but not in sera from several species of normal animals, in antisera prepared against a variety of othet viruses and bacteria or sera from swine with bacterial enteritis. when the immunodiffusion test was compared with the virus neutralizati ...1976187295
leukocyte-aggregation assay for transmissible gastroenteritis of in vitro leukocyte-aggregation assay was developed to detect the exposure of swine to transmissible gastroenteritis virus. leukocytes in heparinized blood samples aggregated when mixed with test antigen prepared from transmissible gastroenteritis-infected swine testicle cell cultures. twenty-two of 23 swine exposed 3 days or more were positive or suspects in the assay; 6 nonexposed swine were negative. aggregation was shown as early as 3 days postexposure in 1 sow and persisted for as long as ...1976187089
vaccination of newborn pigs with an attenuated strain of transmissible gastroenteritis virus.clinical signs of transmissible gastroenteritis were not observed in newborn pigs orally inoculated with the high-passaged vaccinal transmissible gastroenteritis virus (to-163 strain). vaccinal viral multiplication in digestive tract of newborn pigs fed colostrum before inoculation and kept at 21 to 22 c was diminished, but was not diminished in those fed colostrum and kept at 10 to 11 c. other groups of newborn pigs inoculated with the attenuated vaccinal virus and kept at 18 to 22 c or at 31 t ...1976187088
further studies on human enteric coronaviruses.comparisons were made between human enteric coronaviruses and the enteric coronaviruses of pigs and calves by negative staining. examination of human intestinal organ culture fluids at various time intervals after inoculation with the human enteric coronavirus showed increasing numbers of particles in the fluids. thin sections of the columnar epithelial cells of these explants showed a number of features consistent with the replication of known human and animal coronaviruses. virus particles fou ...1977196571
neutralization of a transmissible gastroenteritis virus of swine by colostral antibodies elicited by intestine and cell culture-propagated virus.cross-protection studies of gilts exposed to 4 transmissible gastroenteritis viruses--ilinois (field strain), miller-3, miller low passage (m-lp), and miller high passage (m-hp) tissue culture-adapted--indicated that only the gilt vaccinated with illinois strain was protected, along with its newborn pigs, against challenge exposure with field virus. similar results were obtained when the 4 viruses were incubated in vitro with colostrum from each of the 4 vaccinated gilts and subsequently used to ...1976183573
micro-indirect hemagglutination test for detection of antibody against transmissible gastroenteritis virus of pigs.a micro-indirect hemagglutination (iha) test was developed for detecting antibody against transmissible gastroenteritis (tge) virus of pigs. tge virus propagated in swine kidney cell cultures was highly purified and concentrated by the combination of ammonium sulfate precipitation, treatment with fluorocarbon, and sucrose density gradient centrifugation. tanned sheep erythrocytes were sensitized with purified virus for use in the iha test. the results of testing 104 serum samples collected from ...1977197119
transmissible gastroenteritis of swine. efficacy assay of an intramammary use vaccine.tge seronegative pregnant gilts were vaccinated by intramammary inoculations with a chemically inactivated (betapropiolactone) cell culture virus vaccine and their nursing pigs were exposed to virus at three days of age. the pig morbidity and survival rates were compared with those of pigs nursing gilts exposed orally to virulent tge virus during late gestation and also with pigs nursing non-vaccinated seronegative sows. the morbidity rates were 100%, 19% and 19%, while the survival rates were ...1976182600
the isolation of reovirus-like agents (rota-viruses) from acute gastroenteritis of piglets.isolations of reovirus-like agents (rotaviruses) were made from nine of 23 outbreaks of piglet diarrhoea on different farms and from both weaned and unweaned piglets. the viruses were shown to be morphologically and anti-genically similar to the rotaviruses of children and calves. gnotobiotig piglets given intranasal inoculations of five different isolates developed acute gastroenteritis, and the virus was re-isolated from the faeces or intestinal contents. the piglet virus was not adapted to re ...1976180294
evaluation of 6-azauridine and 5-iododeoxyuridine in the treatment of experimental viral infections.the potential antiviral activity of 6-azauridine and 5-iododeoxyuridine was evaluated in a coordinated study at five institutions. experimental models in five species, the mouse, rabbit, swine, cat, and ferret, were established with use of 10 viruses: herpesvirus hominis types 1 and 2, murine cytomegalovirus, vaccinia virus, shope fibroma virus, transmissible gastroenteritis virus, swine influenza virus, feline viral rhinotracheitis virus, feline panleukopenia virus, and ferret distemper virus. ...1976180189
partial characterization of the principal soluble antigens associated with the coronavirus of transmissible gastroenteritis by complement fixation and immunodiffusion.a microtiter complement fixation (cf) test to detect transmissible gastroenteritis (tge) viral antigen was developed, using tge hyperimmune pig serum as an antibody source. sera from tge covalescent pigs did not fix complement by this test. maximal virus and soluble antigen (sa) titers were obtained 36 to 48 h after inoculation of swine testes cells. cell-associated virus and sa titers were higher than those in the culture fluid, which had to be concentrated 20x before use as antigen in agar imm ...1976177369
pathogenicity of an attenuated strain of transmissible gastroenteritis virus for newborn pigs.the pathogenicity of a cell culture-attenuated strain of transmissible gastroenteritis virus for newborn pigs was investigated. newborn (1- to 2-day-old) pigs were orally given 2 x 10(6) plaque-forming units of attenuated virus. all pigs developed mild diarrhea, but deaths did not occur. as determined by immunofluorescence and villous atropy, infection of the small intestine was limited to the caudal 50 to 66%. fluorescing cells and atrophic villi were seen from 2 to 3 days until 6 to 7 days aft ...1976176906
comparison of intestinal (illinois strain) and cell culture-adapted (m-hp strain) viral populations of transmissible gastroenteritis of swine.intestinal and cell culture-adapted viral populations of transmissible gastroenteritis (tge) of swine were compared by means of sucrose gradient centrifugation, immunnofluorescence, electron microscopy, immune electron microscopy, statistical analysis of the number of plaque-forming units, and ultraviolet sensitivity. results indicated that the size range and general coronavirus morphologic characteristics were shared by both viral populations. marked morphologic variations existed among particl ...1977201184
cell culture propagation of porcine rotavirus (reovirus-like agent).two isolates of porcine rotavirus (reovirus-like agent) were isolated and passaged in primary procine kidney cell cultures. viral infectivity for cells was monitored by immunofluorescence because viral cytopathic effect was moderate. successful passage of virus in cell culture required that viral suspensions obtained from infected cell cultures be treated with pancreatin prior to inoculation onto cell monolayers. porcine rotavirus passage in cell culture also was accomplished, using trypsin trea ...1977201198
[diagnosis of transmissible gastroenteritis of swine]. 1977202057
recovery of transmissible gastroenteritis virus from chronically infected experimental pigs.transmissible gastroenteritis (tge) virus was reisolated from pulmonary and intestinal tissues from 6 of 9 chronically infected experimental pigs (principals) necropsied 30 to 104 days after inoculation. tissue homogenates (lung and small intestine) from the principals were prepared and inoculated into 3- to 5-day-old gnotobiotic pigs. the virus reisolated from the tissue homogenates produced a milder disease on 1st passage and a more severe disease on 2nd passage. the chronically infected exper ...1975171980
the polypeptide structure of transmissible gastroenteritis virus.the polypeptides of purified preparations of the coronavirus responsible for transmissible gastroenteritis of pigs have beem examined by polyacrylamide gel electrophoresis. four major polypeptides, vpi (mol. wt. 200000), vp2 (50 000), vp3 (30000) and vp4 (28500) and two minor polypeptides, vpia (105000) and vpib (80500) have been reproducibly demonstrated in the virion, of which vpi, vp3 and vp4 contain carbohydrate. treatment of the virion with the proteolytic enzyme bromelain removes the surfa ...1975171335
rotavirus as a cause of diarrhea in pigs.a rotavirus (reovirus-like agent) was associated with diarrheal diseases occurring in 1- to 4-week-old suckling pigs in 8 herds and in weaned pigs in 2 herds. transmissible gastroenteritis virus was also detected in 2 of these herds, as was enteropathogenic escherichia coli in 5 herds. morbidity was generally greater than 80% in pigs of the affected age group within these herds, and mortality from diarrhea ranged from 7 to 20%. the disease due to rotavirus in suckling pigs appeared similar to th ...1978203565
transmissible gastroenteritis (tge) of swine: effect of age of swine testes cells culture monolayers on plaque assays of tge virus.a continuous line of swine testes cell culture monolayers was infected at various ages with both cell culture-adapted transmissible gastroenteritis (tge) virus and tissue infected with tge virus. both produced increasing numbers of plaques as the cell monolayers aged from two to five days. therefore, allowing the swine testes cell monolayer to age five to six days before inoculation should increase the likelihood of detecting tge virus by plaque assay.1975169972
viral susceptibility of a cell line derived from the pig oviduct.seventeen of 24 rna viruses and eight of nine dna viruses replicated in a cell line derived from a pig fallopian tube. the following rna viruses grew poorly in it: the virus of transmissible gastroenteritis of pig and the swine-influenza, sendai and bovine para-influenza type 3 viruses. among other rna viruses an untyped swine para-myxovirus and some picornaviruses, rhabdoviruses and togaviruses attained high titers and produced an extensive cytopathic effect. among the dna viruses a porcine ade ...1975169971
[attempts to develop an immunoprevention for transmissible gastroenteritis (tge) in swine. ii. immunogenicity of the b1 strain following serial passages]. 1978207054
the demonstration of transmissible gastroenteritis viral antigens by immunoelectrophoresis and counterimmunoelectrophoresis.immunoelectrophoresis of alkaline intestinal extracts, or the supernatants after precipitation of these extracts with 60% ammonium sulfate, prepared from piglets experimentally infected with the dl or purdue strains of transmissible gastroenteritis virus, revealed up to three antigens. two antigens migrated towards the anode, and the third migrated towards the cathode. antigens with anodal or cathodal mobility were also demonstrated in the same materials by counterimmunoelectrophoresis, and the ...1975167926
upper respiratory infection of lactating sows with transmissible gastroenteritis virus following contact exposure to infected piglets.ten breeding sows were left in direct contact with their newborn piglets that had been experimentally infected with transmissible gastroenteritis (tge) virus. all sows became infected with the virus. the sows developed fever and showed mild clinical signs of the disease for a few days. the sows excreted virus in the nasal secretion, feces, and milk during the acute febrile phase of illness. virus was isolated from the nasal secretion of one sow as early as 20 hours after contact exposure to the ...1975166796
[isolation of the virus of transmissible gastroenteritis of swine from cell cultures and antigenic comparison of 2 american strains]. 1975164273
a new coronavirus-like particle associated with diarrhea in swine.coronavirus-like particles were detected by electron microscopy in the intestinal contents of pigs during a diarrhea outbreak on 4 swine breeding farms. diarrhea was reproduced in experimental pigs with one of the isolates, designated cv777, which was found to be distinct from the 2 known porcine coronaviruses, transmissible gastroenteritis virus and hemagglutinating encephalomyelitis virus.197883132
antigenic relationship of the feline infections peritonitis virus to coronaviruses of other species.utilizing the direct and indirect fluorescent antibody procedure, the antigenic relationship of the feline infectious peritonitis virus (fipv) to 7 other human and animal coronaviruses was studied. fipv was found to be closely related to transmissible gastroenteritis virus (tgev) of swine. transmissible gastroenteritis virus and fipv were in turn antigenically related to human coronavirus 229e (hcv-229e) and canine coronavirus (ccv). an interesting finding in the study was that the 8 coronavirus ...197881044
classifying gastroenteritis viruses. 197578165
methanol precipitation of transmissible gastroenteritis virus.methanol precipitation of transmissible gastroenteritis virus was tested at ph 4.0, 5.0, 6.0, and 7.0 and at methanol concentrations of 15%, 25%, and 30%. supernatant and precipitate fractions were tested for complement-fixing and agar-diffusion soluble antigens and plaque-forming units, and were examined by electron microscopy. virus could be obtained free of detectable agar-diffusion antigens and most of the complement-fixing antigens. most of the virions were without peplomers after methanol ...197943107
comparison of properties between virulent and attenuated strains of transmissible gastroenteritis virus.strains of transmissible gastroenteritis (tge) virus possessing different pathogenicity were examined for stability to digestive enzymes and acid, and growth at various temperatures. in growth experiments, virus titer obtained at 37 degrees c were about equal between attenuated and virulent strains, but titers attained by the attenuated strain were higher at 30 degrees c. the attenuated virus multiplied at 28 degrees c, but the virulent virus did not at this temperature. the virulent virus was s ...19751684
immune electron microscopy of transmissible gastroenteritis virus and rotavirus (reovirus-like agent) of swine.immune electron microscopy (iem) was developed as a diagnostic aid for detecting and identifying transmissible gastroenteritis virus and rotavirus (reovirus-like agent) in fecal and intestinal contents from cases of gastroenteritis in young pigs. variables involved in use of direct iem and its sensitivity were determined. aggregates of virus coated with specific antibody were seen in virus samples mixed with homologous convalescent antiserum, but not in control samples containing preexposure ser ...1977189646
quantitative transmissible gastroenteritis virus shedding patterns in lactating test the role of sows in spreading transmissible gastroenteritis (tge), 11 sows were intravenously, intranasally, or intramammarily inoculated with virulent virus within 5 days of farrowing. six of the sows were separated from their offspring, and 5 were allowed to nurse their litters. all sows became clinically ill with sign of anorexia, depression, and fever that persisted until postinoculation day 4 or 5. they shed virus through milk, nasal secretions, and feces, with individual variations ...1977192108
lipids of transmissible gastroenteritis virus and their relation to those of two different host cells.the lipids of two cell types (primary pig kidney and secondary adult pig thyroid) and those of transmissible gastroenteritis virus (tgev) grown in these cells were studied using 14c-palmitic acid. differences were demonstrated between the incorporation of isotopically labelled lipid precursors in the two cell types and it was found that the phospholipid and glycolipid profiles of purified tgev closely resembled those of the host cell in which it was grown.1977192838
transmissible gastro-enteritis of swine in the netherlands the application of the direct fluorescent antibody techique for diagnosis.the epizootiology of transmissible gastro-enteritis (tge) of swine in 1975 and 1976 in the netherlands was studied. diagnosis was made by the direct fluorescent antibody technique (fat). specimens from the small intestine of suspected animals were examined for this purpose. the results obtained by the direct fat were proved to be reliable, if the specimens were derived from acutely sick animals and examination could be carried out as soon as possible. the results confirmed that tge occured in an ...1977196358
immunoglobulin classes of antibodies in milk of swine after intranasal exposure to pseudorabies virus or transmissible gastroenteritis virus.experiments were conducted to evaluate whether infection of the respiratory tract of pregnant swine with pseudorabies (pr) virus would induce the secretion of immunoglobulin a (iga) antibodies in their milk as was observed after enteric infection with transmissible gastroenteritis (tge) virus. the immune response of sows to pr virus inoculated intranasally and to tge virus inoculated orally/intranasally or via a natural infection was studied. emphasis was placed upon titers and ig classes of pr ...1977197014
lymphocyte proliferative response to viral antigen in pigs infected with transmissible gastroenteritis virus.development and sequence of lymphocytes reactive to viral antigen in peyer's patches, mesenteric lymph nodes, spleen, and peripheral blood of pigs orally inoculated with transmissible gastroenteritis virus were investigated by a lymphocyte proliferative assay. lymphocytes reactive to the viral antigen were first detected in all the tissues of pigs tested on postinoculation day 7. thereafter, they increased in proliferative reactivity and reached a maximal amount on postinoculation days 10 to 14. ...1979217826
[problems in the specific prophylaxis of viral gastroenteritis in swine]. 1977197381
[indirect hemagglutination reaction in viral (transmissible) gastroenteritis in swine]. 1979219585
leukocyte migration-inhibition procedure for transmissible gastroenteritis viral antigens.swine exposed to transmissible gastroenteritis viral antigens developed humoral and cell-mediated immunity. migration of leukocytes from exposed swine was inhibited in the presence of the sensitizing antigens, whereas migration of leukocytes from nonexposed swine was not inhibited in the presense of these same antigens. in virus-neutralization-positive animals, it was not possible to correlate degree of inhibition with virus-neutralization titer. inhibition was observed 7 days after exposure and ...1977199095
vaccination experiments against transmissible gastroenteritis (tge) of swine. v. relationship between the titre and the antigenic effect of the vaccine. 1976200132
detection of transmissible gastroenteritis virus neutralising antibody in cats.high titres of neutralizing activity to transmissible gastroenteritis virus (tgev), a porcine coronavirus, were found in sera and peritoneal fluids from cats infected with feline infectious peritonitis (fip). a small proportion of cats, from a hospital population unaffected by fip, also had neutralising activity. procedures to remove non-specific viral inhibitors, including treatment by heat inactivation, trypsin, sulphydryl reagent and kaolin absorption were unsuccessful. the active component w ...1977200203
transmissible gastroenteritis: demonstration of the virus from field specimens by means of cell culture and pig inoculation.isolation of transmissible gastroenteritis virus was attempted from segments of jejunum collected from piglets submitted for diagnosis of transmissible gastroenteritis. the virus was isolated more frequently in susceptible piglets than in pig kidney or pig thyroid cells. practically, both cell systems were equally capable of demonstrating the virus when the tissue suspensions were sonicated. the pig thyroid cells prepared with glands collected from minimal disease pigs were preferred to the pig ...1977200316
[test of an attenuated viral strain of tge as a vaccine].a live vaccine was produced using a local strain p of the virus of the transmissive gastroenteritis, arrenuated in cell cultures. the vaccinated pregnant sows had high-titer serum and colostrum virus-neutralizing antibodies. in the first days following farrowing there were in the colostrum ummunoglobulins of the igg class that prevailed, however, iga and igm proved more effective in the virus-neutralizing test. newborn pigs acquired passive immunity at about the 24th hour after the intake of col ...1977202064
virus isolation and serum antibody responses after infection of cats with transmissible gastroenteritis virus. brief report.transmissible gastroenteritis virus was administered orally to cats. no clinical disease resulted but infectious virus was isolated from faeces for up to 22 days after infection and serum antibody was detected by neutralisation and immunofluorescence tests.1979226036
[immunity indices in viral (transmissible) gastroenteritis of swine]. 1979229625
vaccination experiments against transmissible gastroenteritis (tge) of swine. vi. a study of the vaccine virus excretion. 1979229722
[some properties of strains of the transmissible gastroenteritis virus of swine (tge) isolated in bulgaria].strains of the swine transmissive gastroenteritis (tge) virus were isolated for the first time in bulgaria in 1972. the dynamics was followed up of some strains' propagation in primary cell cultures of kidney tissue and subcultures of the thyroid of pigs. the intracellular virus reached highest titers at the 24--48th hour in the kidney cells, and at the 24--36th hour in the thyroid cells, while the extracellular virus was subjected to inactivation by the 2nd hour after infecting the cultures, by ...1975175555
a seroepizootiologic study of five viruses in a swine-evaluation station.this serologic study was done to gain information on the spread, maintenance, and effect upon performance of five porcine viruses. blood samples were taken from two groups of 8- to 11-week-old pigs from a large number of indiana swine herds in a performance-testing station 1 week after entry, 7 weeks after entry (one group only), and at slaughter. the sera were tested by indirect fluorescent antibody tests for antibodies to transmissible gastroenteritis virus (tgev), swine influenza virus (siv), ...1979230762
[attempts to establish an immunoprevention of transmissible gastroenteritis (tge) in swine. i. pathogenicity of the b1 strain following serial passages]. 1977202115
intrafetal inoculation of swine with transmissible gastroenteritis virus.fetuses in 3 sows were inoculated (intramuscularly) with transmissible gastroenteritis (tge) virus on 95th, 77th, and 74th days of the gestation. at 15, 14, and 37 days later (or days when pigs were obtained by hysterectomy), there was evidence of intestinal localization of virus, with villous atrophy and subsequent repair. all intrafetal-inoculated pigs became serologic-positive for tge. a noninoculated pig shown to be seropositive for tge at 15 days of age (after hysterectomy) was resistant to ...1978208434
passive immunization against transmissible gastroenteritis virus in piglets by ingestion of milk of sows inoculated with attenuated virus.pregnant sows were inoculated with the attenuated strain, to--163, of swine transmissible gastroenteritis virus. suckling piglets born from them received challenge inoculation with the virulent virus at 3 days after birth, and examined for ability to prevent infection and the immunoglobulin (ig) classes of antibody in milk. a pregnant sow was inoculated intramuscularly with a dose of 10(8.0) tcid50 and intranasally with a dose of 10(9.3) tcid50 of attenuated virus. piglets born from it suffered ...1978211443
colostral iga, igg, and igm-iga fractions as fluorescent antibody for the detection of the coronavirus of transmissible gastroenteritis.colostrum from sows and gilts inoculated with virulent transmissible gastroenteritis virus was fractionated into the 3 major immunoglobulin classes, iga, igg, and igm-iga fractions, by chromatographic and gel-filtration procedures. each fraction was assayed for purity with rabbit anti-porcine serum and rabbit monospecific anti-porcine igg, anti-porcine iga, and anti-porcine igm. these analyses showed that the igg and iga fractions were pure. the igm fraction contained some iga in the polymeric f ...1978211888
protective effect of immunoglobulins in serum and milk of sows exposed to transmissible gastroenteritis virus.experimental exposure of susceptible pregnant sows by various routes to the gut-origin transmissible gastroenteritis virus stimulated production of milk and serum antibodies. these antibodies neutralized the cytopathic effect of transmissible gastroenteritis virus propagated in cell culture. this in vitro neutralizing antibody resided in the igg and iga immunoglobulin classes. on the other hand, protection for baby pigs resided in the iga class of milk immunoglobulin of sows exposed orally or in ...19751111857
[transmissible gastroenteritis of swine as a model for infectious diarrhea].transmissible gastro-enteritis is a virus-caused diarrhoeal disease of swine which may result in up to a total loss among newborn animals. changes are, primarily, of pathologicoanatomic nature and take place in the small intestine. the epithelium of the intestinal villi is completely destroyed, and diarrhoea is the result. deformation in blood composition is a secondary sequel. the diarrhoea proper causes dehydration and acidosis which, in conjunction with abnormal heart function due to hyperkal ...1978211981
[resistance and inactivity of transmissible gastroenteritis virus of swine (tge)]. 1978212010
isolation of subviral components from transmissible gastroenteritis virus.exposure of purified transmissible gastroenteritis virus, a porcine coronavirus, to non-ionic detergents resulted in the removal of the surface projections and greater than 98% of the virus lipid. virus rna was associated with a subviral particle which had a sedimentation coefficient of 650s, compared with 495s for the intact virion, and which banded in cs2so4 gradients at 1-295 g/ml. negatively stained preparations of subviral particles were shown by electron microscopy to contain spherical par ...1976190341
field trials on transmissible gastroenteritis live virus vaccine in newborn piglets.field trials were conducted on attenuated live virus vaccine of transmissible gastroenteritis to confer active immunity to newborn piglets. to examine innocuity and efficacy of the vaccine, a total of 714 newborn piglets were subjected to these trials. of them, 357 piglets were administered orally with 10(7.0) tcid50 within 3 days after birth, and the other 357 piglets served as nonvaccinated controls. no undesirable postvaccinal reaction was observed in any vaccinated piglet. suckling piglets b ...1978216927
transmissible gastroenteritis in neonatal dogs: experimental intestinal infection with transmissible gastroenteritis virus.fourteen neonatal dogs (4 through 11 days of age) were exposed orally to the purdue strain of transmissible gastroenteritis (tge) virus, and six dogs of similar age were noninoculated controls. clinical signs of enteric disease did not develop. both exposed and control dogs had normal fecal passages and appetite throughout the experiment. jejunal epithelium from dogs euthanatized at 12, 24, 48, and 96 hours and at 10 days after exposure did not exhibit morphologic alterations detectable by light ...1979229745
monoclonal antibodies to the spike protein of feline infectious peritonitis virus mediate antibody-dependent enhancement of infection of feline macrophages.antibody-dependent enhancement of virus infection is a process whereby virus-antibody complexes initiate infection of cells via fc receptor-mediated endocytosis. we sought to investigate antibody-dependent enhancement of feline infectious peritonitis virus infection of primary feline peritoneal macrophages in vitro. enhancement of infection was assessed, after indirect immunofluorescent-antibody labelling of infected cells, by determining the ratio between the number of cells infected in the pre ...19921309922
seroepidemiology of feline infectious peritonitis virus infections using transmissible gastroenteritis virus as antigen. 1977341605
isolation of transmissible gastroenteritis virus from pharyngeal swabs obtained from sows at slaughter.a virologic survey was conducted to determine the frequency of transmissible gastroenteritis (tge) virus infection in farm-raised sows. pharyngeal swab specimens collected in an abattoir were examined for tge virus by inoculation onto swine-testes cell culures. the virus was detected in 61 (3%) of a sample of 2,058 iowa sows after slaughter. all tge viral isolates, given orally to 2- or 3-day-old pigs, caused acute gastroenteritis and in some cases death. all pigs that recovered from illness had ...1978206173
[action of actidion on the replication of the transmissible gastroenteritis virus].explored was the possibility of inhibiting the replication of the virus of the transmissive gastroenteritis by means of actidione. it was found that in certain concentrations the antibiotic completely inhibited the replication of this virus. in individual strains the process of replication was not influenced by the various concentrations applied. it was demonstrated that when the antibiotic was added to the infected cell cultures during individual phases its varying concentrations influenced the ...1978210563
small plaque variant transmissible gastroenteritis virus.a small plaque (sp) variant transmissible gastroenteritis (tge) virus strain that may be useful in the control of tge in swine has been developed and tested. this strain was derived from a persistently infected swine leukocyte cell line originally infected with a virulent tge virus. the sp viral strain was avirulent for 3-day-old susceptible pigs and pregnant gilts. the sp virus elicited protective antibody when inoculated into pregnant gilts oral/intranasally, or intramammarily, or by both of t ...1978212409
comments on transmissible gastroenteritis vaccine. 1978212410
effects of ambient temperatures on induction of transmissible gastroenteritis in feeder pigs.experiments were carried out to investigate the effects of ambient temperatures on the induction of transmissible gastroenteritis in feeder pigs 2 to 3 months old. pigs maintained at a high temperature (30 +/- 2 degrees c) and exposed to the virulent transmissible gastroenteritis virus did not show clinical signs of the disease during their maintenance at the high temperature. on the other hand, a sudden decrease in the ambient temperature, either before or after virus inoculation, induced sever ...1978213387
the postulated role of feeder swine in the perpetuation of the transmissible gastroenteritis virus.clinical, immunofluorescence and histopathological observations were found to be an efficient approach for the confirmation of the diagnosis of transmissible gastroenteritis in feeder swine. two cases are reported to exemplify how feeder swine exposed to points of concentration such as holding areas, sales barns and auctions can play an important role in the epizootiology of transmissible gastroenteritis. a third field case is reported as an example of an outbreak of transmissible gastroenteriti ...1978217504
the use of immunofluorescence techniques for the laboratory diagnosis of transmissible gastroenteritis of swine.over a four year period, 74 of 250 field outbreaks of enteric disease (30%) and 110 of 440 swine (25%) were positive for transmissible gastroenteritis by immunofluorescence procedures. of 141 swine from herds positive for transmissible gastroenteritis 110 (78%) were positive by fluorescent antibody techniques. the fastest, easiest to perform and most effective procedure was the examination of frozen sections of the jejunum from acutely ill animals by the fluorescent antibody tissue section techn ...1978217505
the mucosal lesion in viral enteritis. extent and dynamics of the epithelial response to virus invasion in transmissible gastroenteritis of piglets. 1979217794
the neutralization of transmissible gastroenteritis virus by normal heterotypic serum.exposure of transmissible gastroenteritis virus of pigs to unheated normal heterotypic serum resulted in a drop in infectivity, an effect which was lost after heating the serum to 56 degrees c for 30 min or by treatments inactivating complement. analysis of virus proteins, rna and lipids, and centrifugation studies showed little difference between inactivated and control virus, but electron microscopy of negatively stained particles after treatment with serum revealed holes in the virus envelope ...1979217957
protein loss in piglets infected with transmissible gastroenteritis virus. 19751130146
humoral and cellular responses in swine exposed to transmissible gastroenteritis virus.swine exposed to attenuated transmissible gastroenteritis virus had higher virus-neutralizing antibody titers than did swine exposed to virulent virus. the cellular response, measured by the direct leukocyte migration-inhibition (lmi) procedure, was greater in swine exposed to virulent virus than in swine exposed to the attenuated virus. leukocytes from exposed swine were inhibited more in the lmi procedure in the presence of the homologeous sensitizing antigen than in the presence of the hetero ...1979222176
passive immunity in transmissible gastroenteritis of swine: immunoglobulin classes of milk antibodies after oral-intranasal inoculation of sows with a live low cell culture-passaged virus. 1979222177
demonstration of cytotoxic lymphocytes to virus-infected target cells in pigs inoculated with transmissible gastroenteritis virus.lymphocytes, cytotoxic to virus-infected target cells, were induced in pigs orally exposed to transmissible gastroenteritis virus. they were studied and experiments were carried out by using autochthonous testicle cells as target cells to avoid genetic incompatibility of effector lymphocytes and target cells. cytotoxic lymphocytes were demonstrated in peyer's patches, mesenteric lymph nodes, spleen, and peripheral blood on postinoculation day (pid) 7. cytotoxic activity of lymphocytes increased ...1979223476
age-dependent resistance to transmissible gastroenteritis of swine. iii. effects of epithelial cell kinetics on coronavirus production and on atrophy of intestinal villi.coronavirus titers in small intestine, degree of villous atrophy and apparent rates of regeneration of intestinal villi were compared in newborn, 3-week-old and adult pigs for 1 week after they were exposed to the transmissible gastroenteritis virus of swine. the response within the newborn group was homogeneous, resulting in high virus titers, maximal villous atrophy and comparatively slow regeneration. in general, virus titers were lower, villous atrophy was less severe and regeneration more r ...19751229058
stability of porcine colostral immunoglobulins iga, iga2, and igm to proteolytic enzymes. 1979224734
concurrent porcine rotaviral and transmissible gastroenteritis viral infections in a three-day-old conventional pig.a 3-day-old suckling pig with diarrhea was necropsied, and immunofluorescent microscopic examination of the small intestinal mucosa, together with immune electron microscopic examination of the large intestinal contents, provided a presumptive diagnosis of a concurrent infection with transmissible gastroenteritis (tge) virus and porcine rotavirus. immunofluorescent microscopic, immune electron microscopic, and serologic data obtained from gnotobiotic pigs experimentally inoculated with the large ...1979224736
adaptation of transmissible gastroenteritis virus to growth in non-permissive vero cells.the cpk cells derived from swine kidney were infected with the attenuated to-163 strain of transmissible gastroenteritis (tge) virus, and fused with uninfected vero cells in the presence of polyethylene glycol. repeated cocultivation of the fused cells with uninfected vero cells rendered the virus to grow in vero cells. the vero cell-adapted virus acquired the ability to infect and produce cytopathic effects in several other non-permissive cell lines of non-porcine origin. no major differences i ...19921309640
single amino acid changes in the viral glycoprotein m affect induction of alpha interferon by the coronavirus transmissible gastroenteritis virus.transmissible gastroenteritis virus, an enteropathogenic coronavirus of swine, is a potent inducer of alpha interferon (ifn-alpha) both in vitro and in vivo. previous studies have shown that virus-infected fixed cells or viral suspensions were able to induce an early and strong ifn-alpha synthesis by naive lymphocytes. two monoclonal antibodies directed against the viral membrane glycoprotein m (29,000; formerly e1) were found to markedly inhibit virus-induced ifn production, thus assigning to m ...19921309909
coronavirus infection in mink (mustela vison). serological evidence of infection with a coronavirus related to transmissible gastroenteritis virus and porcine epidemic diarrhea virus.antibodies to a transmissible gastroenteritis virus (tgev)-related coronavirus have been demonstrated in mink sera by indirect immunofluorescence, peroxidase-linked antibody assays and immunoblotting. this is the first serological evidence of a specific coronavirus infection in mink. the putative mink coronavirus (mcv) seems to be widespread in the danish mink population with a prevalence approaching 100%. analysis by immunoblotting has shown that mcv is closely related to tgev by the spike (s), ...19921319622
genetic evolution and tropism of transmissible gastroenteritis coronaviruses.transmissible gastroenteritis virus (tgev) is an enteropathogenic coronavirus isolated for the first time in 1946. nonenteropathogenic porcine respiratory coronaviruses (prcvs) have been derived from tgev. the genetic relationship among six european prcvs and five coronaviruses of the tgev antigenic cluster has been determined based on their rna sequences. the s protein of six prcvs have an identical deletion of 224 amino acids starting at position 21. the deleted area includes the antigenic sit ...19921326823
aminopeptidase n is a major receptor for the entero-pathogenic coronavirus tgev.coronaviruses, like many animal viruses, are characterized by a restricted host range and tissue tropism. transmissible gastroenteritis virus (tgev), a major pathogen causing a fatal diarrhoea in newborn pig, replicates selectively in the differentiated enterocytes covering the villi of the small intestine. to investigate the molecular determinants of the infection, we characterized the surface molecule used by the virus for binding and entry into host cells. here we report that aminopeptidase n ...19921350661
transmissible gastroenteritis: sodium transport and the intestinal epithelium during the course of viral enteritis.sodium transport, mucosal structure, and epithelial enzymes were studied in piglets killed 10, 25, 40, 72, or 144 hr after infection with a standard dose of transmissible gastroenteritis virus. glucose-stimulated na transport measured in short-circuited jejunal epithelium and suspensions of villous enterocytes became progressively more abnormal during the first 40 hr, but recovered completely by 144 hr. as na transport deteriorated, jejunal mucosal villi shortened and crypts deepened; cells isol ...1977832794
properties of the "ckp" transmissible gastroenteritis virus strain. i. immunofluorescence assay on the viral replication in cell cultures. 1976205121
clinical and pathologic effects of oral administration of transmissible gastroenteritis vaccine to gnotobiotic pigs.pigs from 3 litters kept under gnotobiotic conditions were inoculated orally with virulent transmissible gastroenteritis (tge) virus, a tge vaccine, or hank's balanced salt solution at 2 days of age and then euthanatized at intervals ranging from 1 to 7 days after inoculation. pigs exposed to the vaccine had clinical evidence of diarrhea and weakness. lesions resembling those of tge were revealed grossly, microscopically, and by scanning electron microscopy. viral antigen was seen in intestinal ...19921311537
intestinal immune response of feeder pigs to infection with transmissible gastroenteritis virus.five feeder pigs 4 to 6 months old were orally inoculated with transmissible gastroenteritis virus. diagnosis of transmissible gastroenteritis was made on the basis of clinical signs and examination of intestinal mucosa by the fluorescent antibody technique. immunoglobulins were extracted from intestinal fluid of infected feeder pigs. virus-binding and neutralizing antibodies were detected in intestinal extracts between 7 and 56 days after infection. the concentration of binding antibodies reach ...1976944001
pathogenicity and antigen detection of the nouzilly strain of transmissible gastroenteritis coronavirus, in 1-week-old piglets.we compared the pathogenicity and the sites of multiplication of the attenuated nouzilly strain, with the highly passaged purdue-115 and the virulent gep ii strains of transmissible gastroenteritis (tge) coronavirus, in 1-week-old weaned piglets. the immunohistochemical peroxidase technique, with an antiviral nucleoprotein monoclonal antibody, was used for the localization of the multiplication sites, in the intestine and other organs. the gep ii and the purdue-115 strains, administered orally t ...19921313460
effect of fixation on the detection of transmissible gastroenteritis coronavirus antigens by the fixed-cell immunoperoxidase technique.the effect of various fixatives and detergents on the in vitro detection of the viral determinants which are expressed in swine testis cells infected with the transmissible gastroenteritis coronavirus (tgev) was studied using a microwell immunoperoxidase technique. when compared with glutaraldehyde and formaldehyde, 0.1% paraformaldehyde was found to be the fixative of choice for the detection of these determinants on the membranes of infected cells. among dehydrating fixatives, 80% acetone or a ...19921328393
antigen selection and presentation to protect against transmissible gastroenteritis coronavirus.the antigenic structure of the s glycoprotein of transmissible gastroenteritis virus (tgev) and porcine respiratory coronavirus (prcv) has been determined and correlated with the physical structure. four antigenic sites have been defined (a, b, c, and d). the sites involved in the neutralization of tgev are: a, d, and b, sites a and d being antigenically dominant for tgev neutralization in vitro. these two sites have specific properties of interest: site a is highly conserved and is present in c ...19921282756
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