Vaccination of fowl with inactivated Newcastle disease vaccine by the respiratory route

Abstract

Chickens were vaccinated with inactivated Newcastle disease (ND) vaccine by the oculonasal, intratracheal (it) or the aerosol route and immunity was measured by determination of haemagglutinating inhibiting (HI) antibodies and survival following challenge. Dose-response to various vaccination schedules was studied in birds of various ages with or without maternal antibodies. IT application induced a stronger response than oculonasal application. A single application with a vaccine dose of 1 to 10 mg allantoic dry matter by the it or the aerosol route resulted in moderate titres in adult birds, while a dose of 0.1 mg still had a priming effect. In one-day-old SPF chicks doses of 1 to 10mg given with adjuvant induced only low titres but protection was present following challenge at 3 to 4 weeks of age, while 0.2 mg had no effect. Maternal antibodies interfered with vaccine efficacy. A more economical use of the vaccine and a better immune response was obtained by repeated vaccination. Twice weekly aerosol exposure, with a dose of about 0.2 mg, induced HI titres of 8 to 9 in 9-week-old hens after four exposures. Five aerosol vaccinations with doses of about 0.1 mg but with adjuvant were effective in young chicks with or without maternal antibodies. In SPF chicks HI titres of 8 to 9 were achieved, while broilers with high levels of maternal antibodies were protected completely against morbidity following challenge. It is concluded that, although repeated aerosol vaccination with inactivated ND virus is effective, it is not economical at present.

Comparison of Newcastle disease vaccine administered as powder or liquid in relation to the serum antibody response and adverse vaccinal reactions in broilers

“…Obviously, this high percentage of very small particles contained sufficient live vaccine virus to induce a strong antibody response after penetrating into the deepest tissues of the lower respiratory tract (atria and air capillaries) (Gough & Allan, 1973;Corbanie et al, 2006), despite virus inactivation due to formation and evaporation of droplets from which these particles emerge. Therefore, it is concluded that the strongest immune response can probably be obtained with vaccine particles of <1 µ, which is in agreement with the results of previous aerosol experiments with inactivated NDV vaccines (Van Eck, 1990). However, considering the current state of art in pharmaceutical technology, it seems almost impossible to manufacture a live vaccine virus containing dry powder that consists mainly of particles <1 µm.…”

An Ulster 2C strain‐derived Newcastle disease vaccine: Vaccinal reaction in comparison with other lentogenic Newcastle disease vaccines

“…Aerosol equipment and characterization procedures have been described (Van Eck, 1990). Aerosol was generated by a Wright nebulizer (Aerosol Products Ltd., London) at an air pressure of 1.5 bar resulting in a flow of 15 ml/h and was transported by an air stream of 15 mVh via a 8.5 cm wide pipe into an isolator of 4.75 m 3 .…”

“…In addition, broilers with maternal ND antibodies and vaccinated at one day of age with inactivated oil emulsion vaccine, show a pronounced immunity gap at 3 and 4 weeks of age (Van Eck, 1987). Also, aerosol application of inactivated vaccine is not practicable for economic reasons (Van Eck, 1990). The virulence of the vaccine virus is a predominant factor in defining the severity of the vaccinal reaction.…”

Primary Newcastle disease vaccination of broilers: comparison of the antibody seroresponse and adverse vaccinal reaction after eye–nose drop or coarse spray application, and implication of the results for a previously developed coarse dry powder vaccine

“…The main drawbacks are the presence of respirable droplets during primer vaccinations, which may induce strong adverse vaccinal reactions, and the virus losses that occur due to shear forces (assessed with porcine respiratory coronavirus using a Delta Spray® gravity feed manual spray gun) (Corbanie, 2007), evaporation (Corbanie et al, 2008;Landman et al, 2015) and sedimentation (estimated maximal loss 0.3 log 10 based on the median volume diameter (D(v, 0.5)). Evaporation of droplets results in formation of dry particles with a concomitant shift in particle size distribution, whereby droplets are reduced in size to approximately 1/10, assuming that the dry matter content is 1 mg/ml and the density of the dry matter is 1 g/cm 3 (Van Eck, 1990).…”