Comparative Immune Response from Vaccinating Chickens with Lentogenic Newcastle Disease Virus Strains

Abstract

The immune response of chickens to 11 isolates of LaSota strain Newcastle disease virus (NDV) and to 7 isolates of B1 strain NDV was studied in specific-pathogen-free chickens. Most of the vaccine strains were from commercial vaccine producers. Comparison of immunogenicity were made of these vaccines; five other lentogenic NDV strains, not used commercially, were also evaluated. From the criteria of hemagglutination inhibition (HI) and virus serum (VN) neutralizing titers, differences were observed with certain isolates within the LaSota and B1 vaccine groups. Whereas the majority of vaccine strains fell within a predictable range, some proved considerably less in their ability to engender expected titers. Two-to threefold differences in titers were observed with some of the strains compared. Two cloned LaSota NDV strains did not compare favorably, or with expected higher titers, with uncloned or conventional LaSota strain virus isolates. Similarly, certain B1 and LaSota strains passaged in chickens did not demonstrate a greater immunogenic potential over conventional, commercial vaccines of similar strain designation but not passaged in chickens. Whereas none of the NDV strains demonstrated evidence of neurotropism or lethality, postvaccination respiratory reactions were difficult, if not impossible, to evaluate in laboratory isolation units. The complexity of selecting ND vaccines for field use is discussed briefly.

Newcastle disease vaccines—A solved problem or a continuous challenge?

“…The VG/GA strain is normally sold as an enterotropic vaccine, and the B1 strain as the most attenuated vaccine to be used in cases of low challenges or in very young birds. While live vaccines provide both mucosal and humoral immunity and can be administered using mass application techniques, they may cause clinical respiratory disease, drop in egg production, and are easily inactivated when not kept at the required temperature (commonly 4 C) (Winterfield and Dhillon, 1981).…”

The resistance of meat chickens vaccinated by aerosol with a live V4 Newcastle disease virus vaccine in the field to challenge with a velogenic Newcastle disease virus

“…The current trials were designed t o be more relevant to the field situation, incorporating practical vaccination of a large flock of commercial chickens housed under Australian field conditions, challenge procedures which simulated natural routes of infection with a velogenic viscerotrophic virus typical of those most likely to enter this country from Asia, and an assessment of the speed as well as the degree of immunity. Borland and Allan (1980) and Winterfield and Dhillon (1981) observed differences between the immunogenicity of different commercial vaccines based on the same virus strain. It is possible that the immunogenicity of the B1 and La Sota preparations used by Westbury might have differed from available commercial vaccines.…”

Evaluation of immunostimulatory effects of a commercial herbal extract on avian influenza subtype H9N2 and Newcastle disease vaccination in chickens

“…Thus, the LaSota strain is nearly always used in countries where virulent NDV is endemic (Diel et al, 2012). The VG/ GA strain is normally sold as an enterotropic vaccine, and the B1 strain as the most attenuated vaccine to be used in cases of low challenges or very young birds (Meulemans, 1988).While live vaccines provide both mucosal and humoral immunity and can be administered using mass application techniques, they may cause clinical respiratory disease, drop in egg production, and are easily inactivated when not kept at the required temperature (commonly 4º C) (Winterfield and Dhillon, 1981). The second group of traditional vaccines that are widely used is vaccine strains from class II genotype I (i.e.…”