NDVs are classified into
velogenic, mesogenic and lentogenic strains based on their pathogenicity (Beard and Hanson, 1984).
The biologic and genomic evaluation based results proposed that pigeon isolates belonged to genotype VI and sub-genotype 'm' as mesogenic whereas teal/duck was found to have genotype VII and sub-genotype 'i' as
velogenic. Interestingly, when compared with vaccine strain (LaSota), the results of present study showed differences in the antigenic epitopes of fusion and HN proteinsforcurrently circulating ND viruses.
coli (O78) and
velogenic Newcastle disease virus in the broiler model.
Pathogenicity indices such as the mean death time (MDT) in 9-10-day-old embryonated chicken eggs and the intracerebral pathogenicity index (ICPI) in 1-day-old chicks are often used to classify the virus isolates into
velogenic, mesogenic, and lentogenic strains [19].
Viruses with high pathogenicity or
velogenic cause serious disease and mortality among affected birds [2].
Newcastle disease virus (NDV) can be grouped into five pathotypes with respect to tissue tropism and clinical signs, that is to say, (a) viscerotropic
velogenic pathotype and (b) neurotropic
velogenic pathotype.
Determination of [EID.sub.50] of locally isolated
velogenic pathotype ND challenge virus
A comparison of the onset of protection induced by Newcastle disease virus strain B1 and a fowl poxvirus recombinant Newcastle disease vaccine to a viscerotropic
velogenic Newcastle disease virus challenge.
La Sota Vaccination May Not Protect against the Lesions of
Velogenic Newcastle Disease in Chicken.
It covers the following: laws and regulations for backyard poultry in the US, common breeds, basic housing and management, husbandry and management, nutrition, and parasitic diseases; physical examination, anatomy, physiology, biosecurity and zoonotic diseases, avian influenza and viscerotropic
velogenic (exotic) Newcastle disease, simple and complex surgeries, and respiratory, musculoskeletal, reproductive, gastrointestinal, hepatic, and cardiovascular diseases; and diagnostics, laboratory sampling and interpretation, medication use, and vaccination.