| Avian Influenza (AT) is an acute, highly contagious disease of birds due to a virus belonging to Influenzavirus in the family Orthomyxoviridae. AI brought tremendous damage to breed aquatics industry and threaten human's life and health since it break out in many areas in the world in the past several years. Wildbird is the huge depository of ATV and it plays an important role in transmitting AI. Investigating the status of wildbirds carrying ATV has Momentous significance for finding out more about the wildbirds' function in transmitting ATV, and controling the breaking out of AI.429 wild birds were collected from some areas in HeiLongjiang province during the period of 2003-05, including a group of mallards collected twice randomly in ZhaLong on August and December, 2004, respectively .Subsequently these samples were detected by RT-PCR and HA and two avian influenza viruses (AIV), D57 sample of H9N2 subtype and DL11 sample of H4N6 subtype, naming as A/mallard/ZhaLong/52/04(H9N2) and A/mallard/ZhaLong/88/04(H4N6), were isolated and identified by hemagglutination inhibition test (HI) and neuraminidase inhibition test from ZhaLong in August in 2004.The separating proportion of avain influenza virus (AIV) is 0.47%. Meanwhile, the two groups of blood serum samples of mallards from ZhaLong above-mentioned were also detected contrastively for antibody against avain influenza virus (ATV) by HI, as a result the two groups of data differ greatly. Among 38 blood serum samples collected on August, there were one sample with antibody against the hemagglutinin (HA) of H1 subtype of avian influenza virus (AIV), none with antibody against the hemagglutinin (HA) of H3 subtype of avian influenza virus (AIV), two samples with antibody against the hemagglutinin(HA) of H5 subtype of avian influenza virus (AIV), none with antibody against the hemagglutinin(HA) of H6 subtype of avian influenza virus (AIV), eight samples with antibody against the hemagglutinin(HA) of H9 subtype of avian influenza virus (AIV), whereas all the 32 blood serum samples collected on December were negative. Although 11 samples were found with antibody against Newcastle Disease Virus (NDV) among blood serum samples collected on August, the Newcastle Disease Virus (NDV) or Avian Paramyxoviruses (APMV) isolation in both the two groups of mallard samples were negative. |
