Aerosol immunization against Newcastle disease

The NDV-6-strain was selected by Lomniczi from naturally occurring Newcastle-disease-virus-strains. This strain was administered to chicken of different ages without detrimental effects. The strain was thermoresistant and adapted by serial passages in gut epithelial cells (NDV-6/10 variant). By using an aerosol of this strain (10(7),(3) EID50/m3) more than 1,3 millions chicken were immunised either in the incubator and up to an age of 10 days. Vaccine reactions were not observed. Vaccination against Marek's disease did not interfere with NDV-vaccination efficacy when day-old chicken were vaccinated with the NDV-6/10 aerosol. Obviously, the vaccine elicits a distinct cell-associated immunity. This explains, why chicken exhibiting low hemagglutination inhibition serum-antibody titers were found resistant to challenge infection with velogenic NDV. Immunity of chicken which have been vaccinated within 1 to 8 days post hatch by the NDV-6/10 aerosol vaccine, persisted 6 to 8 weeks and can be extended by revaccination up to onset of laying. The vaccine is now commercially available and designated VITAPEST.     

The immunization of pheasants against Newcastle disease]

ND-Adsorbatvakzine "Dessau" and Lasovak are well effective and tolerated in pheasants as immuno-prophylactic methods against Newcastle disease infection. Lasovak produces higher titres of antibodies and better rates of protection. The antibodies are created quicker too and reduced more slowly. There is no correlation between the average of antibody level and rate of protection after experimental infection. Even if antibodies are not demonstrable in hemagglutination inhibition test there is still existing a satisfactory protection. After two vaccinations in the age of chickens in 3 to 4 weeks interval and repetition after always 16 weeks pheasants can be protected effectively for the rearing and breeding seasons.     

Immunization of broiler breeder chickens against Newcastle disease with an oil-emulsion vaccine

Antibody response was rapid and high in broiler breeder chickens receiving 1 or 2 vaccinations with oil-emulsion vaccine against Newcastle disease at 23 or at 23 and 26 weeks old. The antibody titers remained high during the 41-week experimental period. At 64 weeks old, about 41 weeks after vaccination, the geometric mean hemagglutination-inhibition antibody titer was 67 from the single vaccination, and 103 from the double vaccination. The immune response to live-virus vaccine given at 2, 9, 20, 30, 42, or 54 weeks of age via the drinking water was high, but uniformity was lacking in the antibody response in the breeders and maternal antibody response in the progeny. Maternal antibody levels in one-day-old chicks were related to the titers of antibody in the dams. Maternal antibody titers of chicks originated from breeder flocks that were vaccinated with the oil-emulsion vaccine remained high for all hatches.     

Antibody reaction to inhalation vaccination of poultry against Newcastle disease]

Aerosol preparated from the AVIPEST vaccine by means of three types of aerosol generators was used for vaccination of 294 chickens of different age against the Newcastle disease in laboratory tests and 30 000 chickens at the age of two and three weeks under field conditions. The general and local antibody reactions to vaccination were evaluated on the basis of the determination of the content of hemagglutination-inhibition and neutralization antibodies in the blood serum and in respiratory-tract flushings. The level of secretory antibodies in the flushings from the respiratory tract, determined by the described original method, is an important parameter of the resistance level of the organism to infection. The highest average levels of antibody titres in serum and in flushings were obtained 14 to 21 days from vaccination (7-10 log2). The La Sota vaccination strain was eliminated from the organism after spray vaccination and immunized the non-vaccinated contact chicken. Revaccination increased and greatly prolonged immunity. All the chickens inoculated showed resistance to challenge infection whereas the control birds died within four to six days.     

Effect of tuftsin on embryo vaccination with Newcastle disease virus vaccine

The effect of tuftsin of embryo and post-hatch vaccination with NDV-F was studied. The embryo vaccination with NDV-F resulted in more number of dead-in-shell embryos. To overcome this problem, the vaccine was treated separately with ethyl methane sulfate (EMS) and 5-fluorouracil (5-FU) and administered. Treating the vaccine with 5-FU resulted in better hatchability as compared to EMS treatment. In embryo, NDV antibody titres increased upto 2 weeks of age and declined thereafter, whereas in post-hatch vaccination, the antibody titre increased from second to fourth week of age and declined thereafter. The seroconversion was better when the vaccine was given along with tuftsin either to embryos or chicks (post-hatch vaccination) as compared to those vaccinated without tuftsin. Moreover, the percentage of hatchability was more in tuftsin administered groups. It was found that embryo vaccination can ensure definite protection during the early life of the chicks despite the presence of maternal antibodies. In cases where breeder vaccinations do not result in concomitant transfer of antibody to progeny chicks, embryo vaccination would give only neonatal resistance. During the later stages, embryo vaccination did not confer any advantage over post-hatch vaccination.     

The immunodepressive effect of infectious bursal agent on vaccination against Newcastle disease.

Immunodepression due to an infectious bursal agent (IBA) infection depends on the age of the birds, the time of Newcastle disease (ND) vaccination and the IBA strain used. The immunodepressive effect of IBA on ND vaccination can be avoided by vaccinating the chicks against ND at day old or by using attenuated strains of IBA in all commercial vaccines.     

Protection conferred by vaccination with Blacksburg and Komarov strains of Newcastle disease virus against Newcastle disease in Bangladesh

Summary An evaluation was undertaken of the efficacy of vaccination of day-old chicks with the Blacksburg (B1) strain of Newcastle disease virus (NDV) followed at various times by vaccination with the Komarov (K) strain. Antibody was detected by the haemagglutination inhibition (HAI) test one week after vaccination with B1 and titres peaked at three weeks and had declined to undetectable levels by nine weeks.After subsequent vaccination with K strain at five, seven or eight weeks of age levels of HAI antibody (titre 80 to 640) were detected after three weeks. Birds vaccinated at seven weeks were tested for antibody and resistance to challenge beyond 19 weeks of age. In this group the HAI titres remained constant (80 to 640) up to 32 weeks of age and then steadily declined to 10 to 20 at 44 weeks of age.A linear relationship between HAI titre and virus neutralising index (VNI) was demonstrated with a range of selected sera. Only birds with an HAI titre of 80 or greater resisted artificial challenge. It is recommended that, following B1 vaccincation at day-old and K vaccination at seven weeks old, revaccination with K strain should be performed at intervals of not more than seven months.

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Proteccion Conferida Mediante Vacunacion Con Las Cepas Blacksburg Komarov Del Virus De Newcastle En Bangladesh

Resumen Se llevó a cabo una evaluación de la eficacia de la vacunación de pollitos de un día, con la cepa Blacksburg (B1) del virus de la enfermedad de Newcastle, seguida de varias aplicaciones vacunales periódicas con la cepa Komarov (K). Se detectaron anticuerpos mediante la prueba de inhibición de la hemaglutinación, una semana después de la vacunación con B1, los títulos alcanzando el pico a las tres semanas y declinaron a niveles no detectables a las nueve semanas.Después de aplicaciones vacunales periódicas con la cepa K, a las cinco, siete u ocho semanas de edad, se detectaron anticuerpos mediante la prueba de inhibición de la hemaglutinación (títulos 80 a 640), después de tres semanas. Las aves vacunadas a las siete semanas, recibieron una descarga y se les hizo prueba de anticuerpos, después de las 19 semanas de edad. En este grupo los títulos de anticuerpos permanecieron constantes (80 to 640) hasta las 32 semanas de edad y después declinaron lentamente a 10 ó 20 a las 44 semanas de edad.Se demostró una relación lineal entre los títulos hallados y el índice viral neutralizante, en un rango de sueros seleccionados. Solamente las aves con títulos de 80 o más altos resistieron la descarga artificial. Se recomienda que, seguidamente a la vacunación con B1 a un día de edad y con K a las siete semanas, las revacunaciones con la cepa K debería hacerse con intervalos de no más de siete meses.

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Protection Conferee Contre La Maladie De Newcastle Au Bangladesh Par La Vaccination A L'Aide Des Souches Blacksburg Et Komarov De Virus De La Maladie De Newcastle

Résumé Une evaluation de l'efficacité de la vaccination de poussins d'un jour à l'aide des souches Blackburg (B1) du virus de la maladie de Newcastle, suivie à différents moments par la vaccination à l'aide de la souche Komarov (K), a été entreprise. Les anticorps furent détéctés par inhibition de l'hemagglutination (HAI), une semaine après la vaccination avec la souche B1 et le titre atteignit un pic à 3 semaines pour décliner jusqu'à des niveaux indétectables à neuf semaines. A la suite de vaccinations consécutives avec la souche K à cinq, sept ou huit semaines, les niveaux d'anticorps HAI furent détectés après trois semaines. Les oiseaux vaccinés à sept semaines furent examinés pour les anticorps et la résistance à une épreuve au delà de 19 semaines d'âge. Dans ce groupe les titres HAI sont restés constants (80 à 640) jusqu'à l'àge 32 semaines, puis ont diminué régulièrement jusqu'à 10 à 20 à l'âge de 44 semaines.Une relation linéaire entre le titre HAI et l'index de neutralisation du virus (VNI) a été démontrée sur une gamme de sérums choisis. Seuls les oiseaux ayant un titre HAI de 80 ou plus ont résisté à l'épreuve artificielle. On recommande que, après une vaccination B1 à un jour, et une vaccination K à l'âge de sept semaines, une revaccination K soit réalisée à des intervalles n'excédant pas sept mois.

     

Failure to induce stress reactions following vaccination against Marek's disease or Newcastle disease

Chickens aged one or 21 days were given single injections of a vaccine against Marek's disease or Newcastle disease respectively, and monitored over a three week period for any signs of a stressor response. No consistent evidence of such a response was found. Some data on normal ontogenetic changes in various adrenal and plasma variables are also presented.     

Onset of progeny immunity against viral arthritis/tenosynovitis after experimental vaccination of parent breeder chickens and cross-immunity against six reovirus isolates

Immunization of breeder chickens by eyedrop with viral arthritis/tenosynovitis vaccine strain S1133 (73rd egg passage) gave no immunity against day-old oral challenge of their progeny at 1 week postvaccination of the breeders, but progeny immunity was observed at 3, 4, 5, 6, and 7 weeks postvaccination of the breeders. Oral cross-challenge of immune progeny with viral isolates from Connecticut, West Virginia, California, Indiana, Pennsylvania, and Minnesota showed that in vitro neutralization of an isolate by anti-S1133 antiserum correlated with in vivo immunity of the progeny against oral day-old challenge with such an isolate.     

Aerosol vaccination against Newcastle disease. I. Studies on particle size.

Studies revealed that the majority of particles emitted by three different aerosol generators were in the size ranges of 0.5-1 and 1-3 mum. In general, the smaller the aperture setting, the larger the total number of particles. The difference between the generators in number of particles emitted were not significant enough to produce appreciable difference in antibody titers obtained from vaccinated chickens. Antibody titers were higher in birds vaccinated with the LaSota strain of Newcastle disease virus than in birds vaccinated with the B-1 strain, although protection against challenge was approximately similar. Aerosol challenge was found as effective as intramuscular challenge.