| 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 ... | 1977 | 189646 |
| 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 ... | 1977 | 201198 |
| pathogenesis of porcine rotaviral infection in experimentally inoculated gnotobiotic pigs. | porcine rotavirus was shown to infect gnotobiotic pigs and induce an acute enteric disease clinically characterized by diarrhea, anorexia, depression, and occasional vomition. onset of clinical signs correlated closely with the appearance of lesions within the small intestinal mucosa, and recovery from infection was associated with the regeneration of normal, functional villous epithelium. villous atrophy, especially in the caudal two-thirds of the small intestine, was the consistent lesion obse ... | 1978 | 204232 |
| morphogenesis of porcine rotavirus in porcine kidney cell cultures and intestinal epithelial cells. | the morphogenesis of porcine rotavirus was similar in vitro in porcine kidney (pk) cell cultures and in vivo in porcine epithelial cells as examined by electron microscopy. infected cells contained cytoplasmic, non-membrane-bound viroplasm and accumulations of virus particles within cisternae of the rough endoplasmic reticulum (rer). three types of virus particles were noted: double-shelled or complete particles which averaged 77 nm in diam.; single-shelled or naked particles which ranged from 5 ... | 1978 | 206653 |
| rotaviral diarrhea in pigs: brief review. | rotavirus is a name given to a group of viruses that have similar characteristics and are generally capable of causing diarrhea in the young. infection of pigs with porcine rotavirus is common and widespread and can result in diarrhea, especially in 1- to 4-week-old pigs. this virus is frequently associated with a diarrheal syndrome popularity known as "white scours," "milk scours," or "3-week-old scours." pigs less than 1 week old are infrequently infected, presumably because of adequate passiv ... | 1979 | 217858 |
| the calf reo-like virus (rotavirus) vaccine: an ineffective immunization agent for rotaviral diarrhea of piglets. | rotavirus, in a commercially available calf vaccine, did not replicate in newborn colostrum-free piglets inoculated orally with one half of a calf dose. gross and microscopic examination of these vaccinated piglets revealed no lesions consistent with rotaviral infection and vaccinated piglets were susceptible to challenge by porcine rotavirus. challenged piglets vomited, had diarrhea and became severely dehydrated. rotavirus was visualized in their gut fluid. villi in the small intestines were s ... | 1979 | 218709 |
| 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 ... | 1979 | 224736 |
| experimental infection of pigs with belgian isolates of the porcine rotavirus. | | 1979 | 231875 |
| expression of the osu rotavirus outer capsid protein vp4 by an adenovirus recombinant. | full-length cdna of the vp4 gene of porcine rotavirus strain osu was cloned into adenovirus type 5 (ad5) downstream of the e3 promoter. the plaque-purified recombinant (ad5-osu vp4) expressed apparently authentic vp4 rotavirus outer capsid protein. the protein had the same molecular size (85 kda) and electrophoretic mobility as did native osu vp4 and was immunoprecipitated by a polyclonal antiserum raised to osu vp4. cotton rats that possessed prechallenge rotavirus antibodies that may have been ... | 1992 | 1318411 |
| intracellular amplification and expression of a synthetic analog of rotavirus genomic rna bearing a foreign marker gene: mapping cis-acting nucleotides in the 3'-noncoding region. | cdnas were constructed to encode plus- or minus-sense analogs of gene 9 rna of porcine rotavirus strain osu in which the bacterial chloramphenicol acetyltransferase (cat) reporter gene was flanked by the 5'-terminal 44 nucleotides (nt) and 3'-terminal 35 nt of the authentic rotavirus gene. transfection of plus-sense gene-9-cat rna into rotavirus-infected cells resulted in its amplification and in the efficient expression of cat; this was greatly enhanced by the presence of a 5' cap structure. am ... | 1992 | 1321421 |
| studies on the age resistance of swine to group a rotavirus infection. | to determine whether swine become naturally age resistant to group a rotavirus infection, colostrum-deprived, rotavirus-naive newborn pigs that were raised in isolation (n = 34) were studied. neonatal pigs and pigs 1, 2, 4, 6, 8, 10, and 12 weeks of age were inoculated orally with group a porcine rotavirus or mock inoculum and euthanatized at 24, 31, or 48 hours post-infection. nine sections of small intestine, cecum, and colon were harvested and immunohistochemically examined for evidence of ro ... | 1992 | 1321528 |
| serotyping and antigenic comparison of some animal rotaviruses isolated in china. | eight strains of rotaviruses isolated from diarrheal animals (4 from calves and 4 from piglets) in china were compared by serotyping with reference animal rotavirus strains (bovine ncdv, porcine osu and simian sa-11 and human rotavirus wa strain). two-way cross neutralization test showed no antigenic difference between all 4 local strains of bovine rotavirus (brv007, brv014, hn-7 and brv6555) and reference ncdv, so they belonged to rotavirus serotype 6 (bovine rotavirus serotype 1 or ncdv-seroty ... | 1992 | 1325720 |
| characterization of full-length and polymerase chain reaction-derived partial-length gottfried and osu gene 4 probes for serotypic differentiation of porcine rotaviruses. | to determine the vp4 (p type) specificity of porcine rotaviruses, full- and partial-length gene 4 probes were produced from cloned gottfried and osu porcine rotavirus genomic segment 4 cdnas. the gene 4 segments from the prototype gottfried (vp7 serotype 4) and osu (vp7 serotype 5) porcine rotavirus strains were selected for study because of their distinct p types and the occurrence of rotaviruses with similar serotypes among swine. partial-length gene 4 cdnas were produced and amplified by the ... | 1992 | 1328281 |
| nucleotide sequence of the cdna for porcine rotavirus vp7 gene (strain k). | the nucleotide sequence of the cdna encoding one of the neutralizing proteins vp7 of the new porcine strain k is determined. the deduced vp7 amino acid sequence of the k strain showed a high homology (93%) and a lower homology (75%) to those of the gottfried and osu strains, respectively. this finding suggests that strain k is more closely related to the gottfried strain serotype 4. | 1992 | 1335631 |
| immunohistochemical detection of porcine rotavirus using immunogold silver staining (igss). | immunogold silver staining (igss) was applied for the detection of porcine group a rotavirus in formalin-fixed paraffin-embedded tissue sections of small intestine. prior to the application of igss, the reactivity of protein a-gold as a marker was tested with group-specific antiserum in immunogold electron microscopy. immune aggregates were intensely and specifically labeled with the gold complex. application of igss to tissue sections resulted in specific dark staining of villous enterocytes in ... | 1992 | 1372832 |
| intestinal permeability in pigs during rotavirus infection. | macromolecular permeability of the small intestine was tested in four 3-week-old gnotobiotic pigs inoculated with porcine rotavirus strain rv277 (group a). pigs were administered 125i-labeled polyvinylpyrrolidone (molecular weight [mol wt], 40,000) orally 1 day before and 2 and 24 hours after virus inoculation, and blood samples were obtained every 6 hours. eight hours after rotavirus inoculation, pigs had watery diarrhea. increased permeation of 125i-labeled polyvinylpyrrolidone was not observe ... | 1992 | 1497189 |
| rotavirus ym gene 4: analysis of its deduced amino acid sequence and prediction of the secondary structure of the vp4 protein. | we have determined the complete nucleotide sequence of the vp4 gene of porcine rotavirus ym. it is 2,362 nucleotides long, with a single open reading frame coding for a protein of 776 amino acids. a phylogenetic tree was derived from the deduced ym vp4 amino acid sequence and 18 other available vp4 sequences of rotavirus strains belonging to different serotypes and isolated from different animal species. in this tree, vp4 proteins were grouped by the hosts that the corresponding viruses infect r ... | 1991 | 1645789 |
| detection of porcine rotavirus in stools by a latex agglutination test. | we developed a simple agglutination test for the detection of porcine rotavirus in stools from pigs with diarrhea. the virus was detected with high sensitivity and specificity by a slide agglutination test using latex particles coated with antibody against the porcine rotavirus strain osu (la-antiosu). the agglutination of la-antiosu with osu on a glass slide was evident macroscopically within 2 min. the sensitivity of this latex agglutination (la) test was four times higher than that of the ele ... | 1991 | 1652863 |
| protection of agammaglobulinemic piglets from porcine rotavirus infection by antibody against simian rotavirus sa-11. | rotavirus, a double-stranded rna virus, has been implicated as a diarrhea-provoking agent in a variety of animal species. several previous reports have shown that immunization with a single serotype may result in increased in vitro neutralization titers against serotypes not represented in the immunogen. this study was undertaken to determine whether antibody from cows immunized against simian rotavirus strain sa-11 (which is alien to pigs) could protect neonatal piglets from infection with a no ... | 1991 | 1653265 |
| identification of atypical rotaviruses in outbreaks of preweaning and postweaning diarrhea in québec swine herds. | intestinal contents of diarrheic pigs from 120 outbreaks of diarrhea were examined for the presence of atypical rotaviruses. pigs involved in these outbreaks were aged two days to five weeks and samples collected over a period of one year originated from different regions of the province of québec. samples were analyzed by polyacrylamide gel electrophoresis (page) for the presence of viral rna and genome profiles were compared to those of porcine rotavirus a/osu, b/ohio and c/cowden. based on el ... | 1991 | 1653639 |
| [stimulation of serum antibody formation in pigs by oral, subcutaneous or combined administration of live porcine rotaviruses or intramuscular inoculation of inactivated porcine rotaviruses in an oil adjuvant]. | only live vaccines prepared from attenuated strains have been used for the specific prophylaxis of rotavirus infections in pigs. these vaccines are administered to sows per os or parenterally to increase the content of antibodies in the blood serum, colostrum and milk, and in this way to provide for the better passive protection of suckling piglets through the maternal antibodies, or to induce the active immunity by pig vaccination. the data on the efficiency of live vaccines administered in bot ... | 1991 | 1668214 |
| [antibody response in mice, rabbits and pigs in response to vaccination with an inactivated oil vaccine containing rotavirus and escherichia coli strains with k88, k99 and 987p fimbrial antigens]. | in trials with mice, rabbits and weanling piglets, four experimental charges of a combined inactivated oil vaccine against diarrhoeas in mammals were tested: the vaccine was to be implanted to sows and it contained porcine rotavirus (prv); two charges also contained bovine rotavirus and bacterins of enterotoxicogenic strains of e. coli with protective antigens k88, k99 and 987p. at low starting antibody titres the twofold i.m. implantation of 0.2 ml vaccine stimulated in mice the production of a ... | 1991 | 1686823 |
| lack of cosegregation of the subgroup ii antigens on genes 2 and 6 in porcine rotaviruses. | the rotavirus subgroup i and ii specificities associated with gene 2 and 6 products (vp2 and vp6, respectively) were shown not to cosegregate in a number of porcine rotavirus strains. the porcine osu rotavirus strain and osu-vp7-like strains were all found to possess a subgroup ii-specific region on vp2 and a subgroup i-specific region on vp6. of interest is the observation that the subgroup ii-specific epitope on vp2 appears to be present only in human and porcine rotavirus strains, suggesting ... | 1990 | 1688386 |
| l-glutamine stimulates jejunal sodium and chloride absorption in pig rotavirus enteritis. | rotavirus enteritis is the leading cause of diarrhea in infants worldwide. a research priority of the world health organization is to develop oral rehydration solutions containing amino acids or other additives that will stimulate intestinal absorption more efficiently than the current glucose-based oral rehydration solutions. glutamine is the principal metabolic fuel of the small bowel and a putative stimulator of mucosal repair. this report describes the transport response to mucosal l-glutami ... | 1991 | 1847119 |
| vp4 monotype specificities among porcine rotavirus strains of the same vp4 serotype. | the porcine rotavirus osu strain was used to produce monoclonal antibodies (mabs) directed against the outer capsid protein vp4. from two separate fusions, eight mabs that inhibited hemagglutination activity of the osu strain were selected. all mabs immunoprecipitated both the osu vp4 protein derived from a lysate of infected ma104 cells and the osu vp4 protein expressed in sf9 cells by a recombinant baculovirus. by immunoprecipitation of in vitro-translated osu gene 4 transcripts of different l ... | 1991 | 1847483 |
| detection of transmissible gastroenteritis virus using cdna probes. | five cdna probes prepared from molecular clones representing genomic rna sequences of the virulent miller strain of transmissible gastroenteritis virus (tgev) were used in a dot blot hybridization assay to detect tgev in cell culture and fecal specimens. two clones (pa2 and pb4) represent nucleotide base pairs at the 3' terminus of the miller tgev genome. the other three clones represent various portions of the 5' end of the e2 gene, which codes for the major surface glycoprotein of tgev. each o ... | 1991 | 1848070 |
| development of hybridization probes on the basis of recombinant dna to identify porcine parvoviruses and rotaviruses. | porcine parvovirus (ppv) and porcine rotavirus (prv) infections can be diagnosed, and the diagnosis greatly contributes to their control. for the diagnosis of ppv and prv of pigs recombinant dna were obtained which could be used as hybridization probes. homology between ppv-rna and cloned cdna was confirmed, and the ability of plasmid probes to detect prv was demonstrated. hybridization with preparations of both ppv-infected cells and purified ppv gave positive reproducible results. the results ... | 1990 | 1966361 |
| ns35 and not vp7 is the soluble rotavirus protein which binds to target cells. | recent studies using radiolabeled rotavirus lysates have demonstrated a 35-kilodalton viral protein that binds specifically to the surface of ma104 cells (n. fukuhara, o. yoshie, s. kitakoa, and t. konno, j. virol. 62:2209-2218, 1988; m. sabara, j. gilchrist, g.r. hudson, and l.a. babiuk, j. virol. 53:58-66, 1985). the binding protein was identified as vp7, an outer capsid glycoprotein and the product of rotavirus gene 9. these studies concluded that vp7 mediated viral attachment to ma104 cells ... | 1990 | 2152820 |
| similarity of the outer capsid protein vp4 of the gottfried strain of porcine rotavirus to that of asymptomatic human rotavirus strains. | genomic segment 4 of the porcine gottfried strain (serotype 4) of porcine rotavirus, which encodes the outer capsid protein vp4, was sequences, and its deduced amino acid sequence was analyzed. amino acid homology of the porcine rotavirus vp4 to the corresponding protein of asymptomatic or symptomatic human rotaviruses representing serotypes 1 to 4 ranged from 87.1 to 88.1% for asymptomatic strains and from 77.5 to 77.8% for symptomatic strains. amino acid homology of the gottfried strain to sim ... | 1990 | 2152826 |
| genome rearrangements in porcine rotaviruses: biochemical and biological comparisons between a supershort strain and its standard counterpart. | two porcine rotavirus strains (cn86 and cc86) isolated during an epidemiological survey of diarrhoea in swine in argentina were studied because of several unique characteristics. both these strains were isolated and cloned from the same faecal sample and the electrophoretic migration of 10 of their 11 genomic dsrna genomic segments in polyacrylamide gels was identical, but strain cc86 had a supershort electropherotype. we analysed biochemical, serological and biological properties of both viruse ... | 1990 | 2155288 |
| a porcine rotavirus strain with dual vp7 serotype specificity. | porcine rotavirus mdr-13, which on original isolation showed a two-way antigenic relationship with human rotavirus rv-3, shows vp7 relationships with serotype g5 as well as g3 viruses upon gene reassortment. analysis of porcine mdr-13 and the md-uk reassortant revealed marked nucleotide and amino acid similarity of vp7 genes of these viruses with those of both serotype g3 and g5 viruses. evolution of such a strain, possibly by sequential mutations in the vp7 gene, is discussed. | 1990 | 2155514 |
| porcine rotaviruses antigenically related to human rotavirus serotypes 1 and 2. | fecal samples from rotavirus-infected piglets were characterized by a serotyping enzyme-linked immunosorbent assay (elisa) by using monoclonal antibodies (mabs) specific to human serotypes 1, 2, 3, and 4 (d. o. matson, m. k. estes, j. w. burns, h. b. greenberg, k. taniguchi, and s. urasawa, submitted for publication). rotavirus in 19 of 25 specimens tested from two herds of pigs from buenos aires province, argentina, were classified antigenically as follows: one serotype 1, four serotype 2, two ... | 1990 | 2157739 |
| evaluation of killed and modified live porcine rotavirus vaccines in cesarean derived colostrum deprived pigs. | twenty-eight cesarean derived, colostrum deprived (cdcd) piglets were used to evaluate the efficacy of killed and modified live rotavirus (mlv) vaccines against challenge with virulent a-1 and a-2 rotaviruses. two killed rotavirus vaccines were evaluated: an experimental vaccine and a commercially available vaccine. efficacy parameters included: average daily weight gains, rotavirus shedding in feces, morbidity incidence and duration, and rotavirus serum antibody conversion post-vaccination and ... | 1990 | 2162098 |
| minimal infective dose of the osu strain of porcine rotavirus. | | 1990 | 2165770 |
| detection of rotavirus antigen in diarrhoeic and non-diarrhoeic piglets in nigeria. | faecal samples from 96 piglets with acute gastroenteritis and 41 samples from non-diarrhoeic piglets were investigated for porcine rotavirus (prv) antigens by enzyme-linked immunosorbent assay (elisa). prv was detected in 43 of 96 (44.8%) in the diarrhoeic group whilst none of the samples in the non-diarrhoeic group was positive for prv (p less than 0.01). age distribution of infection showed a higher infection rate of 30.2% in piglets aged 1-3 weeks, which was significantly higher (p less than ... | 1990 | 2171108 |
| serotypic differentiation of group a rotaviruses with porcine rotavirus gene 9 probes. | the serotypic specificities of gottfried and osu porcine rotavirus gene 9 probes were investigated in a dot hybridization assay. the probes were reacted with homologous and heterologous serotypes of group a rotaviruses of human and animal origin. hybridizations were conducted under relatively low-stringency (52 degrees c, no formamide, 5 x ssc) and high-stringency (52 degrees c, 50% formamide, formamide, 5 x ssc) conditions (1 x ssc is 0.15 m nacl plus 0.015 m sodium citrate). under conditions o ... | 1990 | 2174902 |
| development of specific nucleic acid probes for the differentiation of porcine rotavirus serotypes. | a dot blot hybridization assay is described for the detection and differentiation of porcine rotavirus serotypes. recombinant complementary dna (cdna) representing gene 9 (the gene encoding the neutralization antigens in vp7 glycoprotein) from osu (porcine rotavirus serotype 1) and gottfried (porcine rotavirus serotype 2) strains were used to determine the optimal hybridization conditions which allow specific detection of group a porcine rotaviruses. probes were prepared by excision of the inser ... | 1990 | 2175528 |
| hybridization probes for the detection and differentiation of two serotypes of porcine rotavirus. | a dot hybridization assay was developed to detect and differentiate two serotypes of porcine rotavirus by hybridization of specific probes to rotavirus rna dotted onto nylon membranes. the assay was conducted using radiolabeled probes prepared from cdna clones of osu (serotype 5) and gottfried (serotype 4) rotavirus gene 9 segments. the probes were prepared by excision of full length cdna copies of gene 9 inserts from recombinant plasmids followed by nick translation and 32p-dctp labeling. rotav ... | 1990 | 2175529 |
| multinucleate enterocytes associated with experimental group a porcine rotavirus infection. | | 1990 | 2278133 |
| passive protection against rotavirus-induced diarrhea by monoclonal antibodies to surface proteins vp3 and vp7. | monoclonal antibodies directed against two rotavirus surface proteins (vp3 and vp7) as well as a rotavirus inner capsid protein (vp6) were tested for their ability to protect suckling mice against virulent rotavirus challenge. monoclonal antibodies to two distinct epitopes of vp7 of simian rotavirus strain rrv neutralized rrv in vitro and passively protected suckling mice against rrv challenge. a monoclonal antibody directed against vp3 of porcine rotavirus strain osu neutralized three distinct ... | 1986 | 2422398 |
| analysis by plaque reduction neutralization assay of intertypic rotaviruses suggests that gene reassortment occurs in vivo. | the sb-1a rotavirus recovered from a diarrheic piglet in the united states is a naturally occurring intertypic rotavirus. when studied by reciprocal neutralization tests, the sb-1a virus was similar, if not identical, to the porcine gottfried virus (serotype 4) and the porcine osu virus (serotype 5). analysis of reassortant viruses prepared from the sb-1a virus and the serotype 2 human ds-1 virus revealed that the antigenic specificity of the outer capsid protein vp3 of sb-1a was shared with the ... | 1987 | 2434522 |
| electron microscopy procedure influences detection of rotaviruses. | technical parameters of electron microscope staining procedures (type of stain, ph of stain, and time of staining) influence particle integrity for three groups of rotaviruses. simian rotavirus sa11 (group a), chinese adult diarrhea rotavirus and porcine rotavirus-like agent (group b), and porcine pararotavirus (group c) were tested. all rotavirus strains were quite stable in uranyl acetate and phosphotungstic acid at ph 4.5 and relatively stable in ammonium molybdate. however, staining with pho ... | 1987 | 2444622 |
| comparative sequence analysis of the genomic segment 6 of four rotaviruses each with a different subgroup specificity. | the nucleotide sequences of the genes that code for the major inner capsid protein, vp6, of the human rotavirus strain 1076 (subgroup i), porcine rotavirus gottfried (subgroup ii), equine rotavirus strain h-2 (non-i/ii) and equine rotavirus strain fi-14 (both subgroups i and ii) have been determined. the sixth segment positive-stranded rna encodes a protein of 397 amino acids in all strains with the exception of strain h-2 in which it encodes a protein of 399 amino acids. alignment of amino acid ... | 1988 | 2455770 |
| high-resolution chromatography of nucleic acids on the gen-pak fax column. | high-performance liquid chromatography (hplc) on a gen-pak fax column has been used to separate and purify microgram amounts of single- and double-stranded dna and rna molecules. hplc of mixtures of dna restriction fragments showed that fragments within the size range 0.125-23.1 kilobase were easily resolved. supercoiled (form i) plasmid dna molecules were readily separated from single-stranded circular dna of the same length and from various dna conformational isomers including nicked (form ii) ... | 1988 | 2462570 |
| vp4 protein of porcine rotavirus strain osu expressed by a baculovirus recombinant induces neutralizing antibodies. | the complete vp4 gene of porcine rotavirus strain osu has been inserted into a baculovirus expression vector under the control of the polyhedrin promoter. the vp4 outer capsid protein, which is a major neutralization antigen in rotavirus, was expressed in high yield in spodoptera frugiperda cells. reactivity with polyclonal and monoclonal antibodies suggested that neutralizing epitopes were functionally unaltered on the expressed vp4. the vp4 produced in this system also induced antibodies in gu ... | 1989 | 2480689 |
| the interferon sensitivity of selected porcine viruses. | the objective of this study was to compare the sensitivity of 11 porcine viruses to the antiviral effects of porcine interferon-alpha in serum from piglets which had been infected 19 h previously with transmissible gastroenteritis virus, and of porcine interferon-beta prepared in pk-15 cells by induction with polyinosinic:polycytidylic acid, in yield reduction assays in pig kidney cells which were treated with interferon before virus challenge, and both before and after virus challenge. the most ... | 1989 | 2492445 |
| neutralizing monoclonal antibodies against three serotypes of porcine rotavirus. | using three serotypes (four strains) of cultivable porcine rotavirus as immunizing antigens, 10 neutralizing monoclonal antibodies were characterized. one vp4-specific monoclonal antibody directed against porcine rotavirus ben-144 (serotype g4) neutralized human rotavirus strain st-3 in addition to the homologous porcine virus. all nine vp7-specific monoclonal antibodies were highly specific for viruses of the same serotype as the immunizing rotavirus strain. one exception was the vp7-specific m ... | 1989 | 2545925 |
| comparative virulence of two porcine group-a rotavirus isolates in gnotobiotic pigs. | the virulence of 2 porcine group-a rotavirus isolates was compared. forty hysterotomy-derived 3-day-old gnotobiotic pigs were inoculated orally with 2 ml of intestinal homogenate containing either the ohio state university (osu) or the south dakota state university (sdsu) strain of porcine rotavirus or were inoculated with medium only. clinical signs of disease, body weight, distribution of viral antigen, fecal excretion of virus, and histologic lesions (observed by light and scanning electron m ... | 1989 | 2548420 |
| subgroup and serotype distributions of human, bovine, and porcine rotavirus in thailand. | the subgroup and serotype specificities of human, bovine, and porcine group a rotaviruses in stool specimens collected in thailand were examined by an enzyme-linked immunosorbent assay by using subgroup- and serotype-specific monoclonal antibodies. a clear yearly change was observed in the serotype distribution of human rotavirus. between 1983 and 1984, serotype 4 was the most prevalent, while the highest frequency of serotype 2 was found between 1987 and 1988. all the bovine and porcine rotavir ... | 1989 | 2550515 |
| epidemiological studies of piglet diarrhoea in intensively managed danish sow herds. iv. pathogenicity of porcine rotavirus. | colostrum-deprived piglets inoculated with rotavirus 24 h after birth developed a profuse diarrhoea that spread to non-inoculated, colostrum-deprived litter mates and, occassionally, to colostrum-fed piglets. case fatality rates in these 3 categories of piglets were 63.2%, 35.7% and 8.3%, respectively. surviving piglets recovered in 1-2 weeks, but shedded virus via the faeces for up to 3 weeks p.i. the d-xylose test revealed severe malabsorption, with extremely flat absorption curves for up to 3 ... | 1989 | 2551154 |
| neutralizing antibody to three different serotypes of porcine rotavirus in pigs. | | 1989 | 2555620 |
| reactivity of vp4-specific monoclonal antibodies to a serotype 4 porcine rotavirus with distinct serotypes of human (symptomatic and asymptomatic) and animal rotaviruses. | thirteen hybridomas secreting vp4-specific monoclonal antibodies against the gottfried strain of porcine rotavirus (serotype 4) were produced and characterized. nine of the hybridomas secreted neutralizing monoclonal antibodies (n-mabs) against gottfried rotavirus. these n-mabs were divided into five distinct groups (groups i to v) according to their patterns of reactivity with different serotypes of human and animal rotaviruses. group i n-mabs (n = 3) were cross-reactive with five different ser ... | 1989 | 2556431 |
| further antigenic characterization of porcine rotavirus ym. | we recently reported that the serotype specificity of ym, a group a porcine rotavirus, is different from those of the previously established rotavirus serotypes, 1 to 6 (a. m. ruiz, i. v. lopez, s. lopez, r. t. espejo, and c. f. arias, j. virol. 62:4331-4336, 1988). here we demonstrate by cross-neutralization studies that rotavirus ym is also antigenically distinct from prototype rotavirus strains of serotypes 7 (ty1), 8 (69m), 9 (wi61), and 10 (b223). a comparison of the serotype-determining am ... | 1989 | 2556438 |
| nucleotide sequence of gene segment 1 of a porcine rotavirus strain. | the nucleotide sequence of gene segment 1, which encodes vp1 of porcine rotavirus strain gottfried, was determined. vp1 is associated with single-shelled rotavirus particles and has been linked to virus transcriptase and replicase enzymatic activities. gene segment 1 is 3302 nucleotides long with a single open reading frame capable of coding for a protein of 1088 amino acids (calculated mol wt 125 kda). the predicted amino acid sequence revealed that vp1 is basic, with a net positive charge of 1 ... | 1989 | 2556853 |
| detection and survival of group a rotavirus in a piggery. | samples of dust, faeces and effluent were collected from a piggery and examined for group a rotavirus, using a commercial elisa test, electron microscopy and inoculation of ma-104 cells. rotavirus antigen was demonstrated in samples collected from farrowing and weaner rooms but not from fattener and sow houses. rotavirus antigen was also detected in samples collected from a weaner room which had been free of piglets for three months. a cytopathic porcine rotavirus (british isolate sw20/21) was k ... | 1989 | 2557702 |
| studies on attenuation of rotavirus. a comparison in piglets between virulent virus and its attenuated derivative. | the development of rotavirus vaccines against acute gastroenteritis for human infants has been accorded a very high priority. several vaccine candidates all of which are live cultivated strains of animal origin have been tested in humans. however the nature of attenuation of these viruses for humans is unknown. in this study we have attenuated a pig rotavirus by 15 sequential passages in cell culture after which the virus no longer causes diarrhoea in piglets. the pathogenesis of infection of th ... | 1989 | 2558635 |
| detection of rotavirus in faecal specimens with a monoclonal antibody enzyme-linked immunosorbent assay: comparison with polyclonal antibody enzyme immuno-assays and a latex agglutination test. | monoclonal antibodies have been produced against the 81/36f strain of rotavirus. one of them, was chosen as diagnostic reagent: it showed high elisa reactivity with all the bovine, human and porcine rotavirus strains tested and reacted with vp6, structural protein product known to support the common rotavirus antigen. a sandwich elisa procedure using the chosen monoclonal as "capture and detecting" antibody was performed to detect rotavirus in faecal samples from experimentally inoculated newbor ... | 1989 | 2558838 |
| experimental rotavirus infection in three-week-old pigs. | thirteen 3-week-old pigs that had been allowed to nurse for the first 16 to 18 hours after birth were orally inoculated with 1 x 10(6.5) tcid50 of porcine rotavirus. all developed diarrhea, anorexia, and vomiting by postinoculation (pi) hour 30. these signs had abated by pi day 6. villus blunting in the small intestine was most severe in the jejunum and ileum of pigs euthanatized between pi days 3 and 5. villi had returned to nearly normal length by pi day 6, although fused villi were seen in a ... | 1989 | 2559635 |
| rotavirus replication in colostrum-fed and colostrum-deprived pigs. | a porcine rotavirus isolate was titrated in neonatal colostrum-fed and colostrum-deprived pigs. the stock rotavirus suspension had a titer of 10(-6.5)/ml and was in its fifteenth cell culture passage in ma-104 cells. fourteen colostrum-fed pigs were orally inoculated with dilutions of the stock virus suspension ranging from undiluted to 10(-5). these pigs did not develop notable clinical signs during the 7-day experimental trial and no pathologic changes were found in intestine, liver, lung, kid ... | 1989 | 2559636 |
| penetration and uncoating of rotaviruses in cultured cells. | early steps of replication (penetration and uncoating) of the osu strain of porcine rotavirus were studied in ma-104 cells. after adsorption of trypsin-treated viruses at 4 degrees, followed by a shifting of the temperature to 37 degrees, particles were seen within coated pits, coated vesicles, and secondary lysosomes, indicating that virus entry occurred by receptor-mediated endocytosis, and that uncoating (removal of the outer capsid) could occur by the effect of lysosomal enzymes. this latter ... | 1987 | 2822601 |
| [molecular drift of rotavirus during attenuation]. | the genome structure and polypeptide composition of a rotavirus virion isolated from piglets is described. proteins p90 and p38 were localized in the external capsid of the virion, and the group-specific antigen of rotaviruses, protein p42, in the internal capsid. minor polypeptides p116, p98, and p92 were associated with the virus core. a scheme of the structure of porcine rotavirus virion is proposed on the basis of the virion ultrastructure and localization of viral proteins in the capsid. at ... | 1987 | 2823483 |
| a comparison of seven strains of porcine rotavirus as studied by serum neutralization and rna electrophoresis. | seven strains of porcine rotavirus, four of which (83/17f, 84/52f, 84/106f, 84/158f) had been isolated from diarrheic piglets in herds located in three regions (lombardia, veneto, emilia) of northern italy, and the remaining three (sw 20/21, osu, s80) obtained from the u.k., usa and japan, respectively, were compared. the study included reciprocal serum neutralization tests as well as genomic rna electrophoresis. the italian isolates together with the u.k. (sw 20/21) and the usa (osu) strains pr ... | 1987 | 2826970 |
| nucleotide sequence of porcine rotavirus (osu strain) gene segments 7, 8, and 9. | | 1988 | 2829124 |
| gene sequence of the vp7 serotype specific glycoprotein of gottfried porcine rotavirus. | | 1988 | 2829137 |
| new porcine rotavirus serotype antigenically related to human rotavirus serotype 3. | serotyping of porcine rotaviruses isolated in ma104 cells from australian piglets with diarrhea showed that two strains belonged to serotype 3 and one strain was antigenically similar to the osu strain of porcine rotavirus (serotype 5). in addition, neutralizing antibodies to human rotavirus serotype 4 (st-3 strain) were detected in serum samples from sows in one area, and so it seems probable that porcine rotaviruses of at least three serotypes occur in australia. | 1988 | 2830302 |
| [heterologous system of immunoenzyme analysis for the diagnosis of human rotavirus infection and its comparison with rna electrophoresis]. | on the basis of porcine rotavirus a heterologous eia test system was worked out and tested for diagnosis of human rotavirus infection. a high sensitivity and specificity of the test system was demonstrated, its results were compared with those of electron microscopy, diffuse precipitation test, and rna electrophoresis. out of 201 specimens (fecal filtrates) collected from children ranging in ages from 14 days to 10 years, rotavirus antigen was detected in 68 (33.8%) rna electrophoresis demonstra ... | 1988 | 2835872 |
| isolation of two new serotypes of porcine rotavirus from pigs with diarrhea. | two group a rotaviruses (isu-64 and isu-65) with subgroup i antigen were isolated from pigs with diarrhea and were shown by two-way neutralization tests to be two new serotypes of porcine rotavirus. | 1988 | 2839130 |
| hemagglutination and hemagglutination-inhibition tests with porcine rotavirus. | | 1987 | 2842539 |
| molecular and antigenic characterization of porcine rotavirus ym, a possible new rotavirus serotype. | in 1983, we isolated a porcine rotavirus (strain ym) that was prevalent in several regions of mexico, as judged by the frequency of its characteristic electropherotype. by a focus reduction neutralization test, rotavirus ym was clearly distinguished from prototype rotavirus strains belonging to serotypes 1 (wa), 2 (s2), 3 (sa11), 4 (st3), 5 (osu), and 6 (ncdv). minor, one-way cross-neutralization (1 to 5%) was observed when antisera to the various rotavirus strains were incubated with rotavirus ... | 1988 | 2845146 |
| the nucleotide sequence of the vp3 gene of porcine rotavirus osu. | | 1988 | 2850544 |
| comparison of two methods for detection of transmissible gastroenteritis virus in feces of pigs with experimentally induced infection. | an indirect, double-antibody sandwich-type elisa for detection of transmissible gastroenteritis virus (tgev) was developed, using a solid phase of rabbit hyperimmune serum and a pool of 3 antipeplomer monoclonal antibodies to trap and to detect the virus, respectively. the technique was used to detect viral antigen in feces of pigs that had been infected with the virulent miller strain, the attenuated purdue strain, or the erica strain (a dutch field isolate) of tgev. the results were compared w ... | 1988 | 2854707 |
| virus enzyme-linked cell immunoassay (velcia): detection and titration of rotavirus antigen and demonstration of rotavirus neutralizing and total antibodies. | virus enzyme-linked cell immunoassay (velcia) for detection and titration of rotavirus antigen has been developed. wild-type porcine rotavirus antigen can be detected and titrated directly from the fecal material within 24 h. porcine osu strain can be titrated higher than 10(-8). the method has also been introduced for the demonstration of rotavirus neutralizing and total antibodies. in velcia the advantages of the cell culture system for virus isolation are combined with enzyme immunodetection ... | 1985 | 2984228 |
| porcine rotavirus-like virus (group b rotavirus): characterization and pathogenicity for gnotobiotic pigs. | a rotavirus-like virus (rvlv) was isolated from a diarrheic pig from an ohio swine herd. this virus infected villous enterocytes throughout the small intestine of gnotobiotic pigs and induced an acute, transitory diarrhea. complete virions were rarely observed in the intestinal contents of infected animals; the predominant particle detected by immune electron microscopy was a corelike particle 52 nm in diameter. the genome of the porcine rvlv was composed of 11 discrete segments of double-strand ... | 1985 | 2984243 |
| in vitro detection of porcine rotavirus-like virus (group b rotavirus) and its antibody. | four isolates of porcine rotavirus-like virus (prvlv) infected ma104 cells and induced syncytium formation after low-speed centrifugation of the inoculum onto the monolayer. ten of 44 (23%) ohio swine sera had prvlv antibodies when tested by indirect immunofluorescence, using prvlv-infected ma104 cell monolayers as antigen. | 1985 | 2987303 |
| a new type of atypical rotavirus in pigs. | two independent isolates of an unusual type of rotavirus were obtained from over 900 faecal samples obtained from piglets with diarrhoea. genome profiles, containing eleven segments, were not characteristic of group a electropherotypes and corresponded to an atypical virus. the profiles were, however, distinct from those of other previously described atypical porcine rotaviruses. serological comparisons showed that the two isolates were related, but unrelated to other known groups of porcine rot ... | 1986 | 3013130 |
| the structure of the rotavirus inner capsid studied by electron microscopy of chemically disrupted particles. | the inner capsid structure of the osu strain of porcine rotavirus was studied by electron microscopy of freeze-dried preparations and of negatively stained chemically disrupted virus particles. the analysis of the particles by the freeze-drying technique revealed a t:13 l (laevo) symmetry for the organization of the inner capsid. treatment of single-capsid rotavirus particles with 30% formamide or 5 m-urea resulted in their degradation, giving rise to very similar products, corresponding to isol ... | 1986 | 3016160 |
| distinct serotypes of porcine rotavirus associated with diarrhea in suckling piglets in southern quebec. | cytopathic rotavirus strains were isolated in cell cultures from the intestinal contents of diarrheic piglets on quebec pig farms where repeated outbreaks of enteritis occurred. all the isolates shared the common group antigens of rotaviruses as revealed by immunofluorescence and counterimmunoelectrophoresis. a hemagglutinating activity was demonstrated with human group o, porcine and guinea pig erythrocytes. at least one of the isolates was clearly distinguished from the american prototype of p ... | 1986 | 3017525 |
| isolation of cytophatic strains of rotavirus from pigs. | twenty-two rotavirus isolates were recovered from piglets suffering from diarrhea. the isolates readily propagated in ma-104 cell cultures where they induced typical cytopathic effects (cpe) and possessed the physicochemicals properties of the members of rotavirus genus, family reoviridae. the electron microscopy study, conducted in ma-104 infected cells, revealed virus particles which possessed the peculiar morphology of rotavirus. the isolates were neutralized by a reference porcine rotavirus ... | 1986 | 3018451 |
| a comparison of rotavirus strains of bovine, simian and porcine origin. | three rotavirus strains of bovine, simian and porcine origin, respectively, were compared. the 3 viruses induced a classic rotaviral infection in newborn, conventionally reared calves. the cross neutralization tests revealed an antigenic identity of simian and porcine rotaviruses and a slight serologic correlation of these two viruses with the bovine rotavirus strain. however, in reciprocal cross protection tests carried out in calves, the simian rotavirus antiserum afforded weak protection to c ... | 1985 | 3021518 |
| detection of transmissible gastroenteritis virus in feces from pigs by reversed passive hemagglutination. | a reversed passive hemagglutination (rpha) method was developed for the detection of transmissible gastroenteritis (tge) virus in the fecal specimens from pigs. ovine erythrocytes fixed with glutaraldehyde and treated with tannic acid were coated with anti-tge virus swine antibodies, which were purified by affinity chromatographic technique linked with purified tge virus. the rpha test was done by the microtiter method. erythrocytes coated with purified specific antibodies were agglutinated by t ... | 1986 | 3022621 |
| heterologous protection against rotavirus-induced disease in gnotobiotic piglets. | administration per os of 2 x 10(6) fluorescent cell-forming units of a human serotype 3 rotavirus (rv-3) protected all of nine gnotobiotic piglets against severe diarrheal disease when they were challenged 10 to 14 days later with 8 x 10(3) fluorescent cell-forming units of virulent wild-type porcine rotavirus (at/76). the porcine virus was similar antigenically to porcine prototype strain osu, previously described as antigenically distinct from all four recognized human serotypes. administratio ... | 1986 | 3023436 |
| vp7 serotype-specific glycoprotein of osu porcine rotavirus: coding assignment and gene sequence. | with a reassortant from a cross of human rotavirus ds-1 (serotype 2) and osu (serotype 5) it was determined that the osu major neutralization glycoprotein antigen (vp7) was encoded by gene segment 9. a full-sized cloned cdna copy of the osu gene 9 was produced and sequenced. hybridization of such labelled cdna with the corresponding segment of a reassortant ds-1 x osu virus confirmed the coding assignment. comparison of the deduced amino acid sequence of the vp7 of osu with those previously dete ... | 1986 | 3023532 |
| characterization of rotaviruses isolated from pigs with diarrhoea in venezuela. | the prevalence of porcine rotavirus infection was studied in 15 different herds located in the north-western region of venezuela. the presence of rotavirus was studied by direct electron microscopy (em) and by an enzyme-linked immunosorbent assay (elisa). from 136 samples analyzed during the six months of the study (september 1983-february 1984), 38 (27.9%) were found to be positive for rotaviruses, with infection more common in animals that were 4-6 weeks old. atypical rotaviruses were not dete ... | 1987 | 3027954 |
| minimal infective dose of rotavirus. | we studied the minimal infective dose of the gastroenteritis virus, rotavirus. increasingly lower doses [10(4), 10(3), 10(1), 1, 10(-2) plaque forming units (pfu)] of the osu strain of porcine rotavirus were administered to highly susceptible (colostrum deprived, cesarean derived) newborn miniature swine piglets. in vitro studies showed that virus infectivity was inactivated in piglet gastric juice, both by low ph and by ph- and concentration-dependent factor(s). these factors remain unidentifie ... | 1987 | 3028333 |
| analysis by rna-rna hybridization assay of intertypic rotaviruses suggests that gene reassortment occurs in vivo. | antigenic characterization of human and animal rotaviruses by the plaque reduction neutralization assay has shown the existence of naturally occurring intertypes. antiserum to m37, a rotavirus strain isolated from an asymptomatic neonate, neutralizes both wa and st3 strains, which are classified as serotype 1 and serotype 4 human rotaviruses, respectively. likewise, antiserum to sb-1a, a porcine rotavirus, neutralizes rotavirus strains belonging to serotype 4 or 5. plaque reduction neutralizatio ... | 1987 | 3029162 |
| induction and characterization of swine beta interferon. | newcastle disease virus (ndv) strain "h" and polyinosinic-polycytidylic acid (poly i:c) were used for interferon (ifn) induction in secondary pig kidney cells. a functional ifn system was detected and characterized. a wide similarity with the correspondent human and bovine systems was appreciated, with particular regard to the kinetics of synthesis. a glycosylated protein was essential for activity in bovine cells, but not in swine cells. poly i:c proved to be a very weak inducer, even in condit ... | 1987 | 3034503 |
| [diagnosis of human rotavirus infection by the dot hybridization method]. | the use of the dot-hybridization assay for the diagnosis of human rotavirus infection was shown to be principally possible. 32p-labeled rna segments of porcine rotavirus transcribed in an in vitro system by activation of endogenous rna-dependent rna-polymerase were used as hybridization probes. the transcripts were synthesized to all 11 segments of the parental virus genome. the method proved to be highly specific and very sensitive detecting 10 picograms of viral rna in fecal filtrates of the p ... | 1987 | 3037796 |
| antigenic and pathogenic relationships of three bovine rotaviruses and a porcine rotavirus. | the antigenic relationships between three bovine rotaviruses, uk, cp-1 and pp-1, and a porcine rotavirus were investigated; their pathogenicity for piglets was also assessed. after propagation and cloning in cell culture, the four viruses were used to produce convalescent and hyperimmune antisera in gnotobiotic animals. for the uk and pp-1 viruses, reciprocal virus neutralization tests gave ratios of homologous to heterologous titres in the range 57 to greater than 2300. taking a 20-fold differe ... | 1984 | 6086808 |
| comparison of a commercial enzyme-linked immunosorbent assay with electron microscopy, fluorescent antibody, and virus isolation for the detection of bovine and porcine rotavirus. | the purpose in this study was to compare the sensitivity of a commercial enzyme-linked immunosorbent assay (elisa) with electron microscopy (em), fluorescent antibody (fa), and virus isolation (vi) for the detection of bovine and porcine rotavirus (rv). seventy-three bovine and 116 porcine accessions were evaluated by 1 or all 4 diagnostic tests, where suitable specimens were available. for the bovine samples, agreement was 33% between fa and em, 33% between fa and elisa, and 92% between em and ... | 1984 | 6093642 |
| [experimental infection of fattening swine with rotavirus: study of local immunity using coproantibodies]. | fattened pigs were experimentally infected with porcine rotavirus (osu strain). viral antigens found in the faeces were analysed over a period of two months (elisa method). we have found no correlation between virus excretion and the clinical manifestation of disease. the local immunity has been analysed in the faeces by the coproantibodies antirotavirus. the different classes of antibody, g, m, a and immune complexes have been determined using the elisa method. the level of iga antibodies was h ... | 1984 | 6097155 |
| characterization of an antigenically distinct porcine rotavirus. | a porcine virus with rotavirus morphology, which was antigenically unrelated to previously described rotaviruses, is described. particles with an outer capsid layer measured 75 nm and those lacking the outer layer were 63 nm in diameter. particles which resembled cores were also identified. the virus was shown to be antigenically distinct from other rotaviruses as judged by immunofluorescence and immune electron microscopy, and it failed to protect piglets from challenge with porcine rotavirus. ... | 1982 | 6175575 |
| antigenic relationships between rotaviruses from different species as studied by neutralization and immunofluorescence. | antigenic relationships between the wa, hochi, ito, hosokawa and nemoto strains of human rotavirus, the sa-11 strain of simian rotavirus, the lincoln strain of bovine rotavirus, the osu strain of porcine rotavirus and the r-2 strain of lapine rotavirus, which were all established in cell culture, were studied by neutralization (nt) and immunofluorescence (if) using guinea pig antisera against these strains. the strains could not be distinguished by indirect if staining of infected cells because ... | 1982 | 6181760 |
| epidemiological aspects of porcine rotavirus infection in venezuela. | the prevalence of porcine rotavirus infection in venezuela was studied from november 1980 to november 1981. rotaviruses were identified in 21.3 per cent of 286 diarrhoeic samples analysed by electron microscopy and in none of the 48 controls. rotaviruses were readily detected throughout the year, which may correspond to the absence of seasonal climatic variations in a tropical country such as venezuela. rotavirus infection was frequently observed in pigs that were two to six weeks old and was ra ... | 1984 | 6205426 |
| rotavirus-like, calicivirus-like, and 23-nm virus-like particles associated with diarrhea in young pigs. | virus particles morphologically similar to caliciviruses and rotaviruses were detected by electron microscopy (em) in the intestinal contents of a 27-day-old diarrheic nursing pig. a third small spherical 23-nm virus-like particle was also observed. calicivirus-like particles averaged 33 nm in diameter. similar to rotaviruses, rotavirus-like particles were present as single-capsid 55-nm forms or double-capsid 70-nm particles. most gnotobiotic pigs orally exposed to samples containing these three ... | 1980 | 6252238 |
| scanning electron microscopy of intestine of gnotobiotic piglets infected with porcine rotavirus. | the development of intestinal lesions caused by the porcine rotavirus were studied in six day old gnotobiotic piglets by scanning electron microscopy. the onset of diarrhea followed an incubation period of 17 to 31 hr. the first detectable lesion was observed in the ileum at 12 hr postinfection, a few hours before the onset of diarrhea. at this time enterocytes appeared swollen and began to separate from each other. seventeen hours after the onset of diarrhea, lesions were quite severe jejunum a ... | 1980 | 6256040 |
| development of immunity to porcine rotavirus in piglets protected from disease by bovine colostrum. | bovine colostrum with rotavirus-neutralizing activity was fed for 10 days to two groups of piglets, one of which was inoculated intranasally with a rotavirus of porcine origin. a third group, which did not receive colostrum, was also inoculated with the virus, and these piglets developed diarrhea, excreted rotavirus in the feces, and died 6 days after infection. in contrast, the infected piglets fed with bovine colostrum remained healthy, although they developed antibody to rotavirus. twenty-sev ... | 1981 | 6262251 |
| detection of porcine rotavirus by em, elisa and ciet. | | 1981 | 6266239 |
| rapid, simple method of preparing rotaviral double-stranded ribonucleic acid for analysis by polyacrylamide gel electrophoresis. | a procedure for extracting rotaviral double-stranded ribonucleic acid (rna) directly from fecal and intestinal specimens collected from calves and pigs is described. this procedure provides a rapid, simple, reproducible method of obtaining rotaviral double-stranded rna preparations suitable for electrophoretic analysis in polyacrylamide-agarose composite gels. the rotaviral genome electrophoretic migration pattern produced by double-stranded rna extracted directly from a specimen by this procedu ... | 1981 | 6270190 |
| isolation of cytopathic porcine rotavirus in cell roller culture in the presence of trypsin. | cytopathic porcine rotavirus was isolated in roller tube cultures of ma-104 cells. faeces of a piglet suffering from diarrhoea, were treated with trypsin which was also added to the maintenance medium. using stationary cultures, virus was not isolated from the same materials. the cytopathic effect was clearly observed after 8 serial passages and the virus titer at the 14th passage level was 10(7) median tissue culture infective doses per ml, or higher. at the 27th passage, rotavirus particles we ... | 1981 | 6271098 |
| light microscopy and ultrahistology of intestinal changes in pigs infected with epizootic diarrhoea virus (evd): comparison with transmissible gastroenteritis (tge) virus and porcine rotavirus infections. | | 1981 | 6277107 |