Study On Immunity Dynamic Status Of The Duck Influenza

The ducklings and breeding ducks were inoculated with oil-adjuvant inactivated AIV H₅N₁ vaccine, H₉N₂ vaccine and H₅N₁-H₉N₂ bivalent vaccine respectively. After the inoculation, the HI title was detected. The T lymphocyte and B lymphocyte in the peri-blood were marked with the method of acid α -naphthyl acetate asterase (ANAE) and the ratio of T lymphocyte to B lymphocyte was determined. The body-weight of the ducks was measured every week in order to value the effect of the vaccine on growth rate. The results showed that:1. It was recommended for the ducklings at two weeks old to be inoculated with oil-adjuvant inactivated AIV H₅N₁, H₉N₂ or H₅N₁-H₉N₂ bivalent vaccine at the first immunity. The level of HI antibody for twice immunity at 2 and 3 weeks old respectively was higher than single immunity at 2-week-old.2. The maternal antibody for ducklings achieved its peak at 3-day-old, decreased at 5-day -old and disappeared at 19-day-old.3. The inactivation with oil-adjuvant AI vaccine had no effect on the duck's growth rate.