Groups of ducks used to evaluate the effect of immunosuppression on persistence of Newcastle disease virus under different treatments.
|Antibody grouping of ducks||Group code of ducks||Number of ducks||Treatments|
|Low antibody level||1a||13||+||+||+|
| Medium antibody level||2a||13||+||+||+|
|+: respective treatment administered; −: no treatment; vNDV: velogenic Newcastle disease virus; Groups tabulated as “a”: immunosuppressed and challenged with vNDV disease virus; Groups tabulated as “b”: immunosuppressed but not challenged; Groups tabulated as “c”: not immunosuppressed but challenged with vNDV; Groups tabulated as “d” are controls for group c: not immunosuppressed nor challenged; Group 3: comprises unvaccinated controls for the 4 test groups.|