Newcastle disease virus: Some biological characteristics of twelve samples isolated in Brazil

Abstract

Twelve Brazilian isolates of NDV were studied through evaluation of their biological properties. Three lentogenic, three mesogenic and six velogenic strains of NDV were identified according to their ICPI. They were differentiated from one another by the comparison of the thermostability, elution time and ability to agglutinate horse RBC. Among the lentogenic strains, two isolates resembled the LaSota vaccinal strain and one the B1 strain. None of the isolates resembled the 2C Ulster strain. The mesogenic sample obtained from turkeys could be differentiated from the two mesogenic chicken isolates. The velogenic sample were divided into 4 groups: rapid eluters - thermostable - (+) HA for horse RBC (one sample); rapid eluters thermostable - (-)HA for horse RBC (3 samples); rapid eluters - thermosensibIe - (-)HA for horse RBC (one sample); slow eluters - thermosensibIe (-)HA for horse RBC (one sample).