Insights into Newcastle disease: Isolation and propagation of non-virulent strain for antigen production

Abstract

The Newcastle disease virus (NDV) strains are categorized into three groups: virulent (velogenic), moderately virulent (mesogenic), and non-virulent strains (lentogenic). The non-virulent LaSota strain is commonly utilized as a live vaccine, offering effective immunity against the virulent strains. This study aimed to cultivate and propagate the Newcastle disease virus in the laboratory, assess cytopathic effects in chicken embryos, and confirm virus growth through a hemagglutination test. The non-virulent LaSota strain, utilized as a live vaccine, was employed for this purpose. The chicken embryonated eggs were inoculated with the NDV, and incubated at 37 °C for 48 hours, and the collected allantoic fluids underwent further processing. Distinct petechial hemorrhages were observed in infected embryos, while un-inoculated eggs displayed normal embryos without any lesions. To validate virus growth, the presence of the virus in the allantoic fluid was confirmed through a hemagglutination test. This discovery serves as a foundational step for preparing Newcastle disease virus antigen, crucial for various laboratory techniques.