共查询到20条相似文献，搜索用时 15 毫秒
1.
The production of interferon by pigs in response to viral and synthetic inducers was studied. The inducers used included polyriboinosinic-polyribocytidylic acid (Poly I:C), swine influenza virus and pseudorabies virus. Following intravenous inoculation of pigs with the inducers, sera were examined for interferon by the plaque-reduction method in porcine kidney (PK15) cell cultures using vesicular stomatitis virus as the challenge inoculum. It was shown that pigs can produce interferon in response to each of these inducers. The pseudorabies virus used in this investigation was found to be a better interferon inducer than the swine influenza virus.
The interferon produced in pigs was identified as an interferon because it was pH stable, non-dialyzable, sensitive to trypsin, non-sedimentable and possessed broad-spectrum antiviral activity as well as host-species specificity.
相似文献2.
J B Derbyshire 《Canadian journal of veterinary research》1989,53(1):52-55
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 sensitive virus to both types of interferon was vesicular stomatitis. A porcine isolate of bovine herpesvirus type 1, hemagglutinating encephalomyelitis virus and porcine enterovirus types 1 and 2 were also highly sensitive to interferon-alpha. There was little reduction in the yield of porcine parvovirus or porcine rotavirus, while swinepox, swine influenza and transmissible gastroenteritis viruses were intermediate in their sensitivity to interferon-alpha. In addition to vesicular stomatitis virus, porcine adenovirus type 3, swine influenza, hemagglutinating encephalomyelitis and porcine rotavirus were highly sensitive to interferon-beta, while swinepox, bovine herpesvirus type 1, porcine parvovirus, transmissible gastroenteritis and porcine enteroviruses were less sensitive than the above viruses to interferon-beta, although all showed significant reductions in virus yield. 相似文献
3.
Isoelectric focusing of infectious particles of porcine pseudorabies virus strains in granulated dextran gels. 总被引：1，自引：1，他引：0 
下载免费PDF全文
下载免费PDF全文 Isoelectric focusing of infectious particles of four strains of porcine pseudorabies viruses (Indiana, Iowa, Shope and an avirulent live-virus vaccine strains) are described. The pseudorabies virus strains exhibited great mobility in the electric field typical of viruses of the herpes group. Strains were considered electrophoretically homogeneous based on their respective isoelectric points. Maximal virus infectivity was concentrated in reproducible, stationary zones representing 73 to 86% of the total virus infectivity initially applied throughout the gels. All pseudorabies virus strains during processing and after isoelectric focusing retained their ability as whole complete particles to typically infect porcine kidney cell cultures. Virus from gel fractions produces foci in cell cultures that specifically reacted with pseudorabies virus fluorescent antibody conjugate. Prevention of foci could be demonstrated by neutralizing with pseudorabies virus monospecific antiserum. Maximal infectivity titers were demonstrated to be directly related to isoelectric points. Strain differences, in relation to virulence in swine, apparently is not related to isoelectric points. 相似文献
4.
5.
Studies on Transmissible Gastroenteritis of Swine I. The Isolation and Identification of a Cytopathogenic Virus of Transmissible Gastroenteritis in Primary Swine Kidney Cell Cultures 总被引：4，自引：3，他引：1 下载免费PDF全文
下载免费PDF全文 A. W. McClurkin 《Canadian journal of veterinary research》1965,29(2):46-53
Two virus isolates from transmissible gastroenteritis (TGE) of swine were adapted to grow in primary swine kidney cells. Growth of the virus was indicated by the resistance of the infected cells to the cytopathic effect of a virus diarrhea virus of cattle, and by the development of large round cells on the cell sheet.
Evidence that these virus isolates were TGE was obtained by the development of signs of the disease followed by death of exposed SPF pigs, or the resistance of the recovered pigs to further signs of disease when they were exposed to virulent TGE contained in virus bearing intestinal tissue.
The in vitro and in vivo serum neutralization tests, along with staining of infected cells by fluorescein conjugated TGE antiserum, gave further indication of the specific nature of the virus growing in the cell cultures.
相似文献6.
Massimiliano Baratelli Lorena Córdoba Lester J. Pérez Jaime Maldonado Lorenzo Fraile José I. Núñez Maria Montoya 《Research in veterinary science》2014
Swine influenza virus is one of the most important pathogens involved in the swine respiratory disease complex. Recent serological surveys showed a high prevalence of swine influenza strains belonging to the H1N1, H1N2 and H3N2 subtypes circulating in pigs in Spain. However, little is known about their genome sequence. Five swine influenza strains were isolated from some unrelated outbreaks occurred during 2006–2007, and their complete genome sequences were determined. Phylogenetic analysis revealed that they belonged to the lineages “Avian-Like” H1N1, “Human-Like” H3N2, and “Human-Like” H1N2, showing tight relationships with early or contemporary strains described in Europe. Notably, one virus of the H1N2 subtype showed genetic and antigenic divergence with the European contemporary strains or vaccinal strains of the same subtype, suggesting that some local and divergent clusters of the virus may pass unnoticed in routinary subtyping. Finally, analysis on the entire pattern of genome segments suggested that a second reassortment event could have influenced the evolution of that divergent H1N2 strain. 相似文献
7.
猪流感病毒H1N1、H1N2和H3N2亚型多重RT-PCR诊断方法的建立 总被引：2，自引：3，他引：2
对我国分离到的猪流感病毒和GenBank数据库中已有的猪流感病毒H1N1、H1N2和H3N2亚型毒株的HA、NA基因核苷酸序列进行分析,分别选出各个病毒亚型HA和NA基因中高度保守且特异的核苷酸区域,设计扩增猪流感病毒H1和H3、N1和N2亚型的2套多重PCR特异性引物,建立了猪流感H1N1、H1N2和H3N2亚型病毒多重RT-PCR诊断方法。采用该方法对H1N1、H1N2、H3N2亚型猪流感病毒标准参考株进行RT-PCR检测,结果均呈阳性,对扩增得到的片段进行序列测定和BLAST比较,表明为目的基因片段。其它几种常见猪病病毒和其它亚型猪流感病毒的RT-PCR扩增结果都呈阴性。对107EID50/0.1mL病毒进行稀释,提取RNA进行敏感性试验,RT-PCR最少可检测到102EID50的病毒量核酸。对40份阳性临床样品的检测结果是H1N1、H1N2和H3N2亚型分别为16份、1份和20份,其它3份样品同时含有H1N1和H3N2亚型猪流感病毒,和鸡胚分离病毒结果100%一致。试验证明建立的猪流感病毒H1N1、H1N2和H3N2亚型多重RT-PCR诊断方法是一种特异敏感的诊断方法,可用于临床样品的早期快速诊断和分型。 相似文献
8.
Separation of a Soluble Antigen and Infectious Particles of Bovine Viral Diarrhea Viruses and their Relationship to Hog Cholera 总被引：6，自引：5，他引：1 下载免费PDF全文
下载免费PDF全文 Donald E. Gutekunst Winston A. Malmquist 《Canadian journal of veterinary research》1963,27(5):121-123
A soluble antigen present in infectious tissue culture fluids was separated from the infective virus particle by ultracentrifugation of two serologically related strains of bovine viral diarrhea viruses, NADL-MD and Oregon C24V.
Neutralizing antibodies against the two viruses were absent in four hog cholera antisera, but present in significant titer in the commercially prepared antiserum. Precipitin tests utilizing the agar double diffusion technique formed a single line of identity between the concentrated soluble antigen of both viruses and NADL-MD and hog cholera antisera. No lines were observed using concentrated virus pellet and noninfected BEK cell antigens or control SPF calf and swine sera.
相似文献9.
The effect of aqueous lead acetate given per os to chickens for 35 consecutive days and the effect of lead on interferon and antibody production was investigated. Chickens were found to tolerate levels of lead as high as 160 mg/kg/day without exhibiting clinical signs or hematological changes in spite of very high levels of lead in the blood (6.2 ppm). It is apparent from these findings that chickens are more resistant to lead poisoning than humans, horses, dogs and wild fowl such as ducks.
Subclinical lead doses did not affect interferon induction in response to statolon and Newcastle Disease virus (NDV)-B1. Interferon concentrations and duration in serum were markedly decreased in chickens which received lead at the 320 mg/kg level.
Long time lead exposure had no marked effect on antibody production to NDV in chickens. No consistent correlation was observed between blood lead concentration and antibody titer.
The results of these studies indicate that long term subclinical lead intake suppresses neither interferon nor antibody production in chickens.
相似文献10.
Vannier P Gourreau JM Kaiser C 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(4):138-143
Experimental infection of specific pathogen free pigs with a swine influenza virus (HSW1N1) and study of the duration of viral shedding 相似文献
11.
12.
Sugimura T Murakami Y Ogawa T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(6):659-660
The susceptibilities of culture cells to twelve avian influenza virus strains were determined with ten established cell lines including MDCK and ESK cells and three primary culture cells. The established cell lines derived from embryonic swine kidney (ESK) and chicken kidney (CK) primary culture cells were more sensitive to the avian influenza viruses than the other eleven cells. The ESK cell had a particularly higher infective titer than the MDCK cell with and without trypsin supplement in culture medium, and dispersion of the infective titers was narrower than that of the MDCK cell. The ESK cell is a suitable candidate for routine work on avian influenza viruses in laboratories. 相似文献
13.
伪狂犬病病毒野毒荧光定量PCR检测方法的建立 总被引：1，自引：0，他引：1
根据伪狂犬病病毒gE基因的序列,设计和合成了一对特异的可用于检测伪狂犬病病毒野毒的PCR引物和一条Taqman荧光探针,采用Li ght Cycl e 480荧光定量PCR仪,建立了一种可实时定量检测伪狂犬病病毒野毒的荧光定量PCR技术。该方法的线性范围为1.0×102～1.0×1010拷贝,灵敏度可达4拷贝。检测速度快,仪器的运行时间仅为1 h。对13株猪伪狂犬病病毒野毒进行了检测,结果均为阳性;与伪狂犬病gE基因缺失疫苗、猪细小病毒和鸭瘟病毒无非特异性反应。与病毒分离培养比较,该方法具有快速、灵敏、特异、定量、重复性好等优点,可望用于临床上伪狂犬病病毒野毒与疫苗毒的区分,伪狂犬病病毒野毒的检测和病毒分布的研究等。 相似文献
14.
D G Rogers M L Frey A Hogg 《Journal of the American Veterinary Medical Association》1991,198(3):450-452
A midwestern producer reported high incidence of conjunctivitis and keratoconjunctivitis in a herd of crossbred finishing swine. Complete necropsy was performed on 3 pigs with bilateral mucopurulent conjunctivitis and chemosis; other gross lesions were not seen. Mycoplasma sp was isolated from conjunctival swab specimens obtained from 1 pig; small numbers of streptococci and coagulase-negative staphylococci were isolated from conjunctival swab specimens from all 3 pigs. Neither swine influenza virus nor pseudorabies virus was isolated from conjunctival swab specimens. Histologically, the 3 pigs had chronic lymphoplasmacytic conjunctivitis with lymphofollicular hyperplasia and foci of epithelial and goblet cell hyperplasia. Ultrastructural examination of conjunctival specimens from the 3 pigs revealed large numbers of Mycoplasma-like organisms adhered to superficial conjunctival cells. Mycoplasma-like organisms also were seen in membrane-bound vacuoles in superficial conjunctival cells. Bacteria (including chlamydiae) or viruses were not seen ultrastructurally. The lymphoproliferative nature of the conjunctival lesion and the evidence of adhered and intracellular organisms suggested an etiologic role for a Mycoplasma-like organism in the disease in these pigs. 相似文献
15.
16.
The antiviral activity of recombinant DNA-derived bovine alpha 1(-1) interferon on an established swine testicular cell line and primary testicular cell cultures derived from swine of various ages (2 days, 3 weeks, and 5 weeks) was determined. Bovine interferon induced a dose-dependent increase in 2-5A synthetase in testicular cells, regardless of the source of the cells. Furthermore, interferon inhibited replication of vesicular stomatitis virus to an equivalent extent in all testicular cell cultures. The results indicate that 2-5A synthetase is a reliable marker of interferon activity in swine testicular cell cultures and that the induction of 2-5A synthetase and antiviral effects of recombinant bovine interferon in primary testicular cell cultures are not dependent on the age of the donor animal. 相似文献
17.
Butylated hydroxytoluene (BHT) was evaluated for antiviral effectiveness on pseudorabies virus (PRV) in cell culture, mice, and swine. When relatively small amounts of BHT were mixed with PRV and incubated at 37 C for 30 or 60 minutes before inoculation into cell cultures, the cell cultures did not become infected with virus. The PRV was not infectious when the virus was treated with BHT and then inoculated intraperitoneally into mice, but was infectious when BHT and PRV were inoculated simultaneously or when BHT was inoculated either 30 or 60 minutes before PRV. Swine fed BHT-medicated feed for 10 days before they were intranasally exposed with virulent PRV did not have overt signs of pseudorabies, had a lower concentration of PRV in nasal mucus than did control swine, and had acceptable blood enzyme and cholesterol concentrations during the experiment. The BHT was detected in tissues of 2 swine after they were fed BHT-medicated feed for 10 days, and higher concentrations of BHT were detected in tissues of 3 swine given BHT feed for 29 days. 相似文献
18.
Genetic diversity of H9N2 influenza viruses from pigs in China: a potential threat to human health? 总被引：3，自引：0，他引：3
Yu H Zhou YJ Li GX Ma JH Yan LP Wang B Yang FR Huang M Tong GZ 《Veterinary microbiology》2011,149(1-2):254-261
Pandemic strains of influenza A virus might arise by genetic reassortment between viruses from different hosts. Pigs are susceptible to both human and avian influenza viruses and have been proposed to be intermediate hosts or mixing vessels, for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. In this study, we summarize and report for the first time the coexistence of 10 (A-J) genotypes in pigs in China by analyzing the eight genes of 28 swine H9N2 viruses isolated in China from 1998 to 2007. Swine H9N2 viruses in genotype A and B were completely derived from Y280-like and Shanghai/F/98-like viruses, respectively, which indicated avian-to-pig interspecies transmission of H9N2 viruses did exist in China. The other eight genotype (C-J) viruses might be double-reassortant viruses, in which six genotype (E-J) viruses possessed 1-4 H5-like gene segments indicating they were reassortants of H9 and H5 viruses. In conclusion, genetic diversity of H9N2 influenza viruses from pigs in China provides further evidence that avian to pig interspecies transmission of H9N2 viruses did occur and might result in the generation of new reassortant viruses by genetic reassortment with swine H1N1, H1N2 and H3N2 influenza viruses, therefore, these swine H9N2 influenza viruses might be a potential threat to human health and continuing to carry out swine influenza virus surveillance in China is of great significance. 相似文献
19.
Comparison of embryonated chicken eggs with MDCK cell culture for the isolation of swine influenza virus 总被引：5，自引：1，他引：4 下载免费PDF全文
下载免费PDF全文 Alfonso Clavijo Dina B. Tresnan Rika Jolie En-Min Zhou 《Canadian journal of veterinary research》2002,66(2):117-121
Embryonated chicken eggs (ECE) and the Madin-Darby canine kidney (MDCK) cell line were compared for isolation of swine influenza virus (SIV) from nasal swabs and tissue samples. Samples originated from 30 pigs experimentally inoculated with 2 × 106 to 2 × 107 embryo infectious dose 50% (EID50)/mL of swine influenza strain A/Swine/Indiana/1726/88 (H1N1). The results were analyzed with McNemar's chi-squared test for symmetry. The results indicated that more samples were SIV-positive with ECE than with tissue culture (P ≤ 0.001), suggesting that ECE remains the system of choice for isolation of SIV. It is recommend that routine use of both SIV isolation systems will increase the sensitivity of detection of virus shedding by considering the differences in growth and tropism of diverse SIV strains. 相似文献
20.
Upper Respiratory Disease in Thoroughbred Horses: studies of its viral etiology in the Toronto area, 1960 to 1963 下载免费PDF全文
下载免费PDF全文 J. Ditchfield L. W. Macpherson Audrey Zbitnew 《Canadian journal of veterinary research》1965,29(1):18-22
From outbreaks of upper respiratory infection of horses in the Toronto area between 1960 and 1963, several viruses have been isolated. The viruses, isolated in tissue cultures or eggs, include an equine strain of Myxovirus parainfluenzae 3; two strains of equine influenza virus, A/equi-1/Prague/56, and A/equi-2/Miami/63; equine rhinopneumonitis virus, and two newly recognized viruses of the horse, equine rhinoviruses. In addition serological evidence suggested a widespread infection with these viruses in the population under study. Because of the identical clinical picture seen and the complex etiology of the disease, immunization against upper respiratory disease of the horse does not appear to be completely feasible at this time. 相似文献