What is immunity? What are the common immunization methods?

Immunization is to inoculate the vaccine or vaccine into the chicken through a certain way, so that the chicken can have an immune response without getting sick, thus producing resistance to infectious diseases within a certain period of time.

Different vaccines have different requirements for vaccination methods. In order to give full play to the vaccine's due effectiveness, the inoculation method should be as close as possible to the natural transmission mode of the disease. There are several common immunization methods.

(1) nasal drops and eye drops are suitable for Newcastle disease Ⅱ and Ⅳ vaccines and attenuated infectious bronchitis vaccines. The advantage is that as long as the operation is careful, the inoculation amount of each chicken is relatively uniform, and the disadvantage is that it is more labor-intensive.

For nasal drops and eye drops, you can use a dropper, an empty eye drop bottle or a 5 ml syringe (the needle tip is bald). Try it with 1 ml water in advance to see how many drops there are. For chicks under 2 weeks old, 50 drops per ml is better, 2 drops per chicken and 25 chickens per ml. If 250 chickens use 1 bottle of vaccine, dilute it to 250/25 = 10 ml. For larger chickens, 25 drops per ml is better, and the above 1 bottle vaccine will be diluted to 20 ml. The vaccine should be diluted with normal saline or water for injection, not with cold water, so as to avoid salt, alkali and other impurities killing some viruses and affecting the effect.

There is no obvious difference between nasal drops and eye drops. Each chicken can drop two drops in one nostril, two nostrils or nose eye, but one eye can't hold two drops. You can't let the chicken go until you see that every drop of vaccine is really sucked into your nose or consumed in your eyes.

(2) The drinking water method is to mix the vaccine into water and let the chickens drink freely. Its advantages are labor-saving and time-saving, suitable for a large group of chickens to be inoculated at the same time, and less stress response. Its disadvantages are uneven immune effect, interference from uneven drinking water and large dosage of vaccine. Vaccines suitable for drinking water include Newcastle disease vaccine, infectious bronchitis vaccine and attenuated infectious bursal disease vaccine.

Precautions for drinking water immunization:

The vaccine titer should be high, and the dose should be increased by 1.5 ~ 2 times.

The water used for vaccine preparation should not contain any substances that destroy the vaccine, such as chlorine, iron, copper, zinc plasma and disinfectants. It is best to use cold boiled water.

The drinking fountains should be thoroughly cleaned, without the above harmful substances, and the quantity should be sufficient to ensure that chickens can drink water at the same time.

0.2% skimmed milk powder or 2% skimmed milk should be added to drinking water to protect vaccines or viruses.

Drinking water containing vaccine should be finished within 2 hours. To do this, you should stop drinking water 3 ~ 5 hours in advance (depending on the season). After the water was stopped, the chickens felt a strong thirst. The water consumption for two hours is about 4-5ml for each chicken aged 5-7 days, 8ml for 10- 14 days, 20ml for 12ml for 28 days 17ml for 40-45 days, and 80ml before the start. Stop eating after drinking chicken 1 hour.

Drinking water immunization must be repeated at least twice in 2 days to ensure the immune effect.

(3) Seed prick method This method is suitable for varicella vaccine and Newcastle disease vaccine. When planting seeds, add 100 dose of vaccine into 1 ml of physiological saline, distilled water or cold boiled water and dissolve evenly. Dip the seed needle or pen tip into the vaccine for 65,438+0 ~ 2 times under the wings without blood vessels to ensure that each chicken can get a vaccine the size of a drop of millet.

(4) injection method This method is to inject the vaccine under the skin or into the muscle. Its dosage is accurate and the effect is positive, but it is time-consuming and laborious. Suitable for Marek's disease vaccine, Newcastle disease vaccine, chicken cholera vaccine and various inactivated vaccines. During injection, 0.5 ~ 1 ml diluent is added to each freeze-dried vaccine, and then 0.5 ~ 1 ml is injected subcutaneously or intramuscularly in the neck, chest or other parts. Marek's disease vaccine must be diluted with a special diluent designated by the manufacturer, and 0.2 ml is injected subcutaneously into the neck of each chicken after dilution. Inject all kinds of inactivated seedlings (aluminum rubber seedlings or oil seedlings) subcutaneously or intramuscularly according to the prescribed dose.

When injected into the chest muscle, the needle should not penetrate vertically or too deeply, so as not to stab the internal organs and cause death. Leg injection should be injected at the plump part of the lateral muscle, not at the inner side, so as to avoid stabbing blood vessels and nerves, causing bleeding and claudication.

(5) The method of aerosol immunization is to put the chicken in a closed room, spray the diluted vaccine into very fine droplets with a special aerosol device, and diffuse them into the air, so that the chicken can be inhaled into the lungs and airbags. This method is suitable for "spreading" attenuated vaccines and so on. The immune effect is good, but it is very irritating to the respiratory organs of chickens and often causes adverse reactions, so it is rarely used.