Abstract
There have been intermittent massive dead of duckling in southern Taiwan since June 2008. After virus isolation and virus characteristic analysis from the specimens delivered to our institute, the etiology of the massive death of duckling was identified to be caused by the duck virus hepatitis type I (DVH-I). To establish the correct vaccination way, we have carried out a serial immune efficiency tests for the current commercial DVH-I live vaccine. The test results indicated that ducks vaccinated by the intramuscular inoculation would get better response than other ways either by spray vaccination or subcutaneous injection, and Tsaiya duck needed 50 times more antigen payload or dose to induce the same level of neutralizing antibody titers as Muscovy duck did post vaccination. The variety of immune response of ducks following vaccination may be relevant to the different species of ducks. Further, the antibody titers induced in one-day old Tsaiya duck post vaccination were low and various no matter which vaccination way were tried. For sound immunity, we suggest that the vaccine should be vaccinated for duckling older than 1-week and by the intramuscular inoculation, and boosted for one or two more times. But for the efficiency and cost concern, we recommend that it had better to vaccinate the breeding ducks for 3 times within 2 to 4 weeks prior to laying eggs, so that the breeding ducks can induce and transfer higher passive antibody titers to their duckling for protection against DVH-I infection.
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Abstract
In 2008, a total of one hundred and twenty-four specimens collected from 61 pig farms were submitted for virus isolation and identification in our laboratory. The positive results of pig farms tested for porcine circovirus 2, porcine teschovirus, porcine enterovirus, porcine respiratory and reproductive syndrome virus, reo virus, pseudorabies virus, swine influenza virus(H1N2), Japanese B encephalitis virus, porcine parvovirus, akabane virus were 27, 17, 17, 8, 7, 3, 3, 1, 1, and 1, respectively. Additionally, mycoplasma hyorhinis was isolated and confirmed from 12 pig farms.
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