Four factors determining the success or failure of Chicken Immunization

1. Vaccine cause

1. Selection and purchase of vaccines: products with formal production license and approval number of the Ministry of Agriculture produced by biological products enterprises that have passed GMP acceptance shall be selected and purchased. The vaccine bottle should be checked carefully when choosing and purchasing. those with broken seedling bottle, no label, illegible label, loose bottle cap, mixed impurities in the vaccine, discoloration, demulsification separation of inactivated vaccine, expired, and not preserved in accordance with the prescribed conditions shall not be selected.

2, the preservation of the vaccine: stored in strict accordance with the instructions, to avoid repeated freeze-thaw inactivation or reduction of titer caused by high and low temperature; sunlight exposure is strictly prohibited; vaccines, vaccine bottles and equipment that have been diluted and used must be inactivated.

3. The time limit for the use of the vaccine: the inactivated vaccine should be used up within 6-8 hours, and the live vaccine should be used up within 2-4 hours after dilution.

4. points for attention in the use of the vaccine: it should be used strictly in accordance with the instructions to ensure that the dose is appropriate and the method is appropriate; disinfectants, anti-bacterial and viral drugs, interferon and immunosuppressants are prohibited before and 7 days after the use of the vaccine; adding appropriate amount of immune promoters such as VA, VC and VE in the feed can improve the immune effect; the new vaccine should be tried on a small scale before using the new vaccine, and then used on a large scale without abnormal reactions.

In addition, the inoculation equipment should be strictly sterilized to ensure that each chicken (at least a single cage) has a needle and a seed needle to avoid cross-infection.

II. Vaccination methods

1. Nose drops and eye drops: the diluted vaccine is dropped into the eye or nasal cavity one by one.

2. Spray use: the spray gun is sprayed 1 meter above the flock, the vaccine dose in this method needs to be doubled, special equipment is needed, and the chicken coop is required to be closed.

3. Drinking water: it is suitable for larger chicken farms, and the water should be cut off in advance. 2-3 hours in summer and 3-4 hours in winter to ensure that each chicken can drink enough vaccine in a short period of time. 0.1% skim milk powder or vaccine protectant (available on the market) can be added to the water to prevent the vaccine from being damaged by water.

4. Injection method: including subcutaneous injection, thorn seed and intramuscular injection.

III. Factors to be considered in the time of immunization

1. The prevalence of local diseases: if there has been no fowlpox in the local area, and the health and epidemic prevention work in the chicken farm has been done well, you may not be vaccinated against fowlpox; if Newcastle disease occurs frequently, you should be vaccinated against Newcastle disease as soon as possible.

2. Maternal antibody level: if the maternal antibody level of chicks is high and the vaccination time is too early, the effect of vaccine will be reduced. In addition, the immune system of chicks is not perfect, and the response to premature inoculation is poor, which can not achieve the desired effect.

3. Antibody level in vivo: if the antibody produced by the previous inoculation does not decrease to a certain extent, the effect of this inoculation will be weakened. Conditional chicken farms had better do antibody monitoring to determine the time of vaccination.

4. Vaccine characteristics: for example, Newcastle disease Ⅰ vaccine has great side effects, and its use during the laying period will affect egg production. Ⅱ line or Ⅳ line can be selected in this period.

IV. Formulation of immunization procedures

1. Master the epidemic situation: before formulating the immunization procedure, we should investigate the disease history of the chicken farm and its surrounding area, so as to determine the type and time of vaccine that should be vaccinated.

2. First immunity and strong immunity: detect the maternal antibody level of chicks, determine the time of first immunization, and determine when to strengthen immunity according to the time of antibody production, immunization period or antibody detection after different vaccination.

3. Infectious diseases: during the epidemic period, inactivated and live vaccines can be used for severe infectious diseases or epidemic infectious diseases at the same time, and it is best to choose a vaccine consistent with the epidemic virus strain.

4. Age and susceptibility: if the susceptibility of Marek's disease chicks is the highest within 24 hours after hatching, inoculation should be carried out within 24 hours after hatching.

5. It is not suitable to be inoculated under stress.