PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “NEWCASTLE DISEASE”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 775 records · Page 43Linked to original sources

[Newcastle disease virus in the populations of wild birds in the south of the Primorye Territory in the period of autumn migrations in 2001-2004].

The paper presents the results of molecular virological monitoring of Newcastle disease virus (NDV) by reverse-polymerase chain reaction (followed by sequence of F-gene fragment 374 p.n.) and chick embryo isolation of samples from the avian cloacal swabs collected in the south of the Primorye Territory in September-October 2001-2004. It shows that before 2004, there were only slightly pathogenic variants of NDV of genotype 1 in this region and in 2004 they were added by highly pathogenic variants of subtypes 3a and 5b. The impact of landscaping features of the south of the Primorye Territory on the environment of NDV is discussed.

Animals↗

Effect of negative air ionization on airborne transmission of Newcastle disease virus.

Four-week-old mixed-sex White Rock chickens were used in four experiments to determine the effect of negative air ion enrichment on airborne transmission of the Roakin strain of Newcastle disease virus (NDV). The experiments were conducted in specially constructed airborne disease transmission cabinets in which donor (upwind) chickens cannot contact susceptible (downwind) chickens because of physical separation by a "no man's land." Temperature and humidity were computer-controlled at 26.7 C and 50% relative humidity, and ventilation rates were manually adjusted from 0.34 to 1.36 m3/min (12 to 48 ft3/min). Donor chickens were inoculated with Roakin NDV by eyedrop and intranasal routes and placed in the upwind end of each cabinet. One day later, susceptible chickens were placed in the downwind end. Seroconversion (> or = 1:10 NDV hemagglutination-inhibition titer) was considered evidence of infection from inoculation (upwind) or airborne transmission (downwind). Commercial air ion generators were used either in the ends or in the "no man's land" of the treatment cabinets and operated at power supply voltages ranging from -8kV direct current to -15 kV direct current. The use of negative air ion generators reduced airborne transmission an average of 6.6% to 27.7% compared with the control cabinets. Significant (P < or = 0.05) reductions in transmission were obtained with some treatments. The greatest reduction in transmission was obtained with the higher power supply voltages (13.8% reduction) and when the ionizers were placed in the "no man's land" (27.7% reduction) between the upwind and downwind chickens.

Air Ionization↗

Integrity of membrane lipid rafts is necessary for the ordered assembly and release of infectious Newcastle disease virus particles.

Membrane lipid raft domains are thought to be sites of assembly for many enveloped viruses. The roles of both classical lipid rafts and lipid rafts associated with the membrane cytoskeleton in the assembly of Newcastle disease virus (NDV) were investigated. The lipid raft-associated proteins caveolin-1, flotillin-2, and actin were incorporated into virions, while the non-lipid raft-associated transferrin receptor was excluded. Kinetic analyses of the distribution of viral proteins in lipid rafts, as defined by detergent-resistant membranes (DRMs), in non-lipid raft membranes, and in virions showed an accumulation of HN, F, and NP viral proteins in lipid rafts early after synthesis. Subsequently, these proteins exited the DRMs and were recovered quantitatively in purified virions, while levels of these proteins in detergent-soluble cell fractions remained relatively constant. Cholesterol depletion of infected cells drastically altered the association of viral proteins with DRMs and resulted in an enhanced release of virus particles with reduced infectivity. Decreased infectivity was not due to effects on subsequent virus entry, since the extraction of cholesterol from intact virus did not significantly reduce infectivity. Particles released from cholesterol-depleted cells had very heterogeneous densities and altered ratios of NP and glycoproteins, demonstrating structural abnormalities which potentially contributed to their lowered infectivity. Taken together, these results indicate that lipid rafts, including cytoskeleton-associated lipid rafts, are sites of NDV assembly and that these domains are important for ordered assembly and release of infectious Newcastle disease virus particles.

Animals↗

Tyrosine kinase activation by Newcastle disease virus is required for TNF-alpha gene induction in astrocytes.

Astrocytes, when appropriately stimulated, produce a variety of cytokines including TNF-alpha. Production of TNF-alpha by astrocytes stimulated with Newcastle disease virus (NDV) is achieved by transcriptional activation and mRNA stabilization. A PKC-dependent pathway is responsible for a 10-fold increase in TNF-alpha mRNA stability by reducing poly(A) tail removal. The present study examined signal pathways induced by NDV in primary rat astrocytes that are responsible for TNF-alpha gene transcription as well as the possible source of kinase activity required for mRNA stabilization. Transcription of TNF-alpha gene in astrocytes stimulated by NDV or LPS and IFN-gamma was inhibited completely by the tyrosine kinase inhibitor herbimycin, and partially by a PKC inhibitor H7, as determined by nuclear run-on assay. HA-1004, a cyclic nucleotide-dependent kinase inhibitor, showed no effect. These results indicated that tyrosine kinase signaling pathways seemed to precede the activation of PKC in induction of TNF-alpha gene. Increase in tyrosine kinase activity in NDV-infected astrocytes was demonstrated by a two- to threefold increase in tyrosine phosphorylation of Pl-PLC gamma 1. Because astrocytes contain minimal Pl-PLC beta, and NDV-induced TNF-alpha mRNA was affected by pertussis toxin only modestly, Pl-PLC gamma 1 is likely the enzyme responsible for DAG generation and the PKC-dependent mRNA stabilization in response to NDV.

Animals↗

Efficacy of a recombinant fowl pox-based Newcastle disease virus vaccine candidate against velogenic and respiratory challenge.

A fowl pox-based recombinant virus TROVAC-NDV (vFP96.5) was developed expressing the fusion and hemagglutinin-neuraminidase glycoproteins from a velogenic strain of Newcastle disease virus (NDV). Studies in specific-pathogen-free birds indicated that inoculation of a single dose of the recombinant led to the induction of significant levels of hemagglutination-inhibiting antibody that were maintained to 8 wk postinoculation. Further, the recombinant induced protective immunity against a combined intramuscular velogenic NDV challenge and respiratory NDV challenge. In commercial broiler chickens that were inoculated in the presence of maternally derived NDV immunity, the level of the NDV-specific humoral response was dampened, but significant levels of protection against both a lethal intramuscular NDV challenge and a fowl poxvirus challenge were obtained.

Animals↗

Serological status for Chlamydophila psittaci, Newcastle disease virus, avian polyoma virus, and Pacheco disease virus in scarlet macaws (Ara macao) kept in captivity in Costa Rica.

From 1998 to 1999, a total of 128 blood samples were collected from scarlet macaws (Ara macao), kept in captivity in 11 different aviaries located in six provinces of Costa Rica. The sera were examined for antibodies directed against Chlamydophila psittaci, Newcastle disease virus (NDV), avian polyoma virus (APV), and Pacheco disease virus (PDV). Testing by enzyme-linked immunosorbent assay (ELISA), showed 16 (12.39%) of the samples (n = 129) exhibited antibodies directed against C. psittaci. Employing haemagglutination inhibition tests for NDV antibodies, all of the samples were found to be negative. The prevalence of antibodies specific for APV was tested with a blocking ELISA and serum neutralization tests (SNT) and 12 of 128 samples (9.37%) were found to be positive with both tests. In SNT, two out of 128 samples (1.56%) were positive for PDV. This is the first description of the serological status in scarlet macaws in captivity in Costa Rica. The study demonstrates the absence of NDV antibodies in the birds investigated on one hand, but also indicates a health hazard for numerous avian species due to the risk of infections with C. psittaci, APV or PDV.

Animals↗

Detection and quantification of antibodies to Newcastle disease virus in ostrich and rhea sera using a liquid phase blocking enzyme-linked immunosorbent assay.

A liquid phase blocking ELISA (LPB-ELISA) was adapted for the detection and quantification of antibodies to Newcastle disease virus. Sera from vaccinated and unvaccinated commercial flocks of ostriches (Struthio camelus) and rheas (Rhea americana) were tested. The purified and nonpurified virus used as the antigen and the capture and detector antibodies were prepared and standardized for this purpose. The hemagglutination-inhibition (HI) test was regarded as the reference method. The cutoff point for the LPB-ELISA was determined by a two-graph receiver operating characteristic analysis. The LPB-ELISA titers regressed significantly (P < 0.0001) on the HI titers with a high correlation coefficient (r = 0.875). The two tests showed good agreement (kappa = 0.82; P < 0.0001), relative sensitivity (90.91%) and specificity (91.18%), and accuracy (91.02%), suggesting that they are interchangeable.

Animals↗

Ameliorative effects of sodium bentonite on phagocytosis and Newcastle disease antibody formation in broiler chickens during aflatoxicosis.

The ameliorative effect of graded levels of dietary sodium bentonite (0.2, 0.4 and 0.6 per cent wt/wt of feed) on in vitro-impaired phagocytosis and suppressed immune response to Newcastle disease vaccine during aflatoxicosis (AF) in broiler chicks was investigated. Both percentage and mean of phagocytic activities were decreased significantly (P < 0.05) in chicks fed 2.5 mg aflatoxin per kg feed. The addition of sodium bentonite was significantly effective in ameliorating the negative effect of AF on the percentage and mean of phagocytosis. The presence of AF alone in the diet depressed the immune response of chicks as measured by haemagglutination inhibition (HI) test. Sodium bentonite was also effective in ameliorating the suppressive effect of AF on the HI -titre in chicks vaccinated against Newcastle disease. The best results obtained when sodium bentonite was added at the rate of 0.4 per cent wt/wt of feed to the AF-containing diets.

Aflatoxins↗

Investigations on the influence of helminth parasites on vaccination of chickens against Newcastle disease virus under village conditions.

Prevalence studies have shown that almost 100% of free-range chickens are infected with a wide range of parasites. The infections are mostly subclinical in nature, resulting in production losses and occasionally mortality. Newcastle disease (ND) on the other hand, results in high mortality rates during epidemics. ND is a limiting factor for increasing poultry production in many tropical countries, where frequent reports indicate vaccination failures. The aim of our study was to investigate the influence of helminths on the antibody response after vaccination against Newcastle disease of free-range chickens naturally infected with parasites. Sixty chickens were divided into six groups, of which three were vaccinated against ND with a live De Soto vaccine, while the other three remained non-vaccinated. One group within the vaccinated groups and the one within the non-vaccinated group was kept naturally infected with helminth parasites, while the other two groups in each set were dewormed with fenbendazole and niclosamide, and one of each of these groups was subsequently infected with Ascaridia galli. After vaccination, all the groups were followed for 5 weeks and their antibody titres were determined weekly using a HI test. All the birds were finally challenged 4 weeks after vaccination with a virulent velogenic ND virus obtained from a field outbreak. All the vaccinated chickens seroconverted and had high antibody levels after 3 weeks, but these dropped to low levels at 4 weeks after vaccination. After challenge, the antibody titres rose in the dewormed groups but not in the parasite-infected groups. After 5 weeks, all the parasite-infected animals had significantly lower antibody titres than the dewormed animals. All the vaccinated chickens survived the challenge infection, emphasizing the importance of the cellular immune response. Further studies are needed to examine the effects of the parasitic infection on protection against ND over a longer period.

Analysis of Variance↗

Comparative characteristics of the Israeli Newcastle disease virus field strains by means of a wide panel of monoclonal antibodies against hemagglutinin-neuraminidase glycoprotein.

Fourteen mouse monoclonal antibodies (MAB) were tested for their ability to react with 15 reference and 52 local Newcastle disease virus (NDV) strains isolated in Israel during the last decade from feral birds. All the field isolates had no antigenic difference when examined by classic serological tests. However, MAB-mediated analysis revealed wide antigenic heterogeneity amongst the studied viruses. By the pattern of the MAB reactivity, all the isolates could be distributed into 13 groups.

Animals↗

Simulated natural infection of chickens with Australian lentogenic newcastle disease virus and subsequent challenge with virulent virus.

A total of 291 eight-week-old chickens were exposed to chickens infected with either of two Australian lentogenic strains (V4 and AVL NDV-1) of Newcastle disease virus (NDV). At 3 weeks after exposure, all chickens exposed to V4 infected chickens had developed haemagglutination-inhibition (HI) antibody. All chickens exposed to AVL NDV-1 virus infected chickens had developed HI antibody 5 weeks later. This sudden late appearance of HI antibody, to titres higher than those observed with V4 chickens, was explained by V4 virus being introduced to the AVL NDV-1 group of chickens. When groups of these chickens were challenged with Roakin virus (mesogenic NDV) at 3 weeks and Fontana 1083 virus (viscerotropic velogenic NDV) and Texas GB virus (neutrotropic NDV) at 3, 5, 10 and 21 weeks only three chickens developed clinical illness one of which died. These chickens were one AVL NDV-1 chicken contact challenged with Fontana 1083 virus at 3 weeks, one V4 chicken oronasally challenged with Texas GB virus at 5 weeks and one V4 chicken challenged oronasally with Fontana 1083 virus at 10 weeks. Susceptible non-vaccinated chickens died soon after challenge. Challenge by oronasal infection with 10(7.0) ELD50 of virus or contact with susceptible infected chickens enabled virulent virus to be isolated from most chickens and was accompanied by a large anamnestic increase in serum HI antibody.

Animals↗

Experimental Newcastle disease virus infections in three species of wild birds.

Three species of wild birds--the red-winged blackbird (Agelaius phoeniceus), an African weaver finch (Quelea quelea), and the sandhill crane (Grus canadensis)--were exposed to Newcastle disease virus (NDV) to determine susceptibility and host response. The NDV used were a vaccine strain (LaSota) and a viscerotropic velogenic strain (New York Parrot). Host response was monitored by virus isolation, signs of disease, and serologic response. Both the red-winged blackbirds and the quelea shed little virus and developed low antibody titers. A low mortality in the blackbirds did not appear to be due to ND alone. Vaccinated cranes were well protected against velogenic challenge, whereas unvaccinated cranes shed the velogenic virus from the cloaca for weeks. The ramifications of the low antibody titers produced in birds of two species are discussed, as well as the potential involvement of each species in transmission of the virus.

Animal Population Groups↗

Detection of antibodies to Newcastle disease virus in ostriches (Struthio camelus) by an indirect ELISA.

A two-graph receiver operating characteristic analysis, performed on the hemagglutination-inhibition (HI) and enzyme-linked immunosorbent assay (ELISA) test results of a Newcastle disease virus (NDV)-positive and NDV-negative control group of ostrich sera, proved that the ELISA was superior to the HI in both sensitivity and specificity. Comparison of results of the two assays performed on a panel of simulated positive sera ranging from very weak to very strong showed that the ELISA was at least 10 times more sensitive than the HI in detecting low levels of ostrich antibodies to NDV. The ELISA also has the advantage of using untreated serum in a single dilution as opposed to the HI test, which uses pretreated serum in titration.

Animals↗