Newcastle Disease Immunization Studies: 4. Vaccination of Chickens with B1, F and Lasota Strains of Newcastle Disease Virus Administered through the Drinking Water

Abstract

ABSTRACT PREVIOUS studies have demonstrated the efficacy of immunizing chickens against Newcastle disease (ND) with B1 strain Newcastle disease virus (NDV) administered through the drinking water under laboratory and field conditions (Winterfield and Seadale, 1955Winterfield and Seadale, 1956Winterfield and Seadale, 1957a,b). In this investigation, F and LaSota NDV strains were used as vaccines in addition to the B1. The results are presented in this paper. MATERIALS AND METHODS B1 strain NDV (Hitchner and Johnson, 1948) vaccine was prepared from stock virus maintained in the authors’ laboratory. F strain NDV was obtained in a dry state from the Newcastle Disease Repository, University of Wisconsin, and the LaSota strain was isolated from a commercial vaccine. The F and LaSota strains were passed through three generations in embryonated chicken eggs before being used as vaccines. Each vaccine was in the form of amnioallantoic fluid (AAF) obtained from infected embryos. The same vaccine pool of each strain was used . . .