Mean individual symptomatic index between 1 to 10 day post inoculation in chickens inoculated with mosaic recombinant IBDV strains.

<p>The symptomatic index was calculated according a scale ranging from 0 to 3 with, with 0 meaning “lack of signs”, 1 meaning “typical IBD signs (ruffled feathers) conspicuous in quiet bird only, the bird stimulated by a sudden change in environment (light, noise, or vicinity of experiment observer) appears normal, motility is not reduced”; 2 meaning “typical IBD signs conspicuous even when bird is stimulated, dehydration is apparent, motility may be slightly reduced” and 3 standing for “typical severe IBD signs with prostration or death”. mc88180 induced significantly more morbidity than all other viruses from 3 to 9 DPI (p≤0.0001 to p≤0.003), whereas no significant difference in the severity of clinical signs was observed between the groups receiving the other viruses or mock-inoculated., A simplified representation of the chimeric segments B (based on the ones described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0028064#pone-0028064-g001" target="_blank">Figure 1</a>) used in association with the segment A of 88180 to generate the indicated mosaic recombinant viruses is shown.