Ten key points to always keep in mind when vaccinating chickens

1. Chicken vaccines, also called antigens, are biological products. They can be divided into attenuated vaccines, moderately virulent vaccines, and virulent vaccines. In terms of production methods, they are further divided into freeze-dried vaccines and wet vaccines, and their storage methods also differ. Freeze-dried vaccines must be stored in a quick-freeze freezer, while wet vaccines, also called liquid vaccines, must be stored in a refrigerator at 0°C~8°C. Because rural refrigeration equipment is incomplete, most @#@230@#@ households are not well-off and do not have refrigerators, so the vaccine must be used immediately after being taken out. Especially in summer, when bringing the vaccine home, ice cubes must be added to lower the temperature, and it is best to add ice water to the drinking water when administering the vaccine in drinking water. Direct sunlight must also be avoided to ensure effectiveness.

2. When purchasing vaccines, first check that the name, approval number, production date, packaging dosage, production site, etc. comply with the provisions of the Measures for the Administration of Veterinary Drug Labels and Instructions. Use fresh vaccines produced recently. Do not use old or expired vaccines or vaccines left over from the previous batch of chickens. Especially if you do not have a refrigerator yourself and store the vaccine in a relative's or neighbor's refrigerator together with frozen fish and meat, it is safer to store it in a professional supplier's freezer. Because rural electricity is frequently cut off, repeated freezing and thawing will damage the quality of the vaccine.

3. Accurately calculate the amount of vaccine used. The amount of drinking water should be increased, while the amount for eye and nose drops should be smaller than the drinking water amount. Strictly use the diluent as required, such as normal saline, cool boiled water, well water, or the specially provided red diluent (for Marek's disease) and blue diluent (for infectious bronchitis). The dilution concentration should be calculated based on the amount of drinking water and the duration of drinking to reach the required dosage. Generally, water should be withheld before administering the vaccine in drinking water, for 2 hours in summer and 3 hours in winter, so that the chickens feel thirsty and drink quickly.

4. Pay attention to the dilution method. The cap of a freeze-dried vaccine bottle is a high-pressure cap. The dilution method is to first slowly inject 5 ml of diluent into the bottle with a syringe. After the vaccine inside the bottle dissolves, open the cap and pour it into the water. This avoids the sudden opening of the vacuum-sealed freeze-dried vaccine bottle cap, which would cause a sudden increase in pressure inside the bottle, impacting some viruses and inactivating them.

5. To improve the immune effect, the viability of the vaccine (virus) should be prolonged, also known as the inactivation half-life. An immune enhancer can be added. For drinking water immunization, 2.4 g of skim milk powder can be added per kg of drinking water. The main components of skim milk powder are protein and carbohydrates. The protein diameter is between 1~2 nm, and its aqueous solution is a colloidal solution. The diameter of viruses is generally between 20~30 nm. Protein molecules are smaller than viruses, so virus particles are surrounded by protein molecules, which can prevent the aggregation of virus particles. This is beneficial for absorption and transformation. If milk powder is not available, Subu 20, Subu 18, Subu 14, or white sugar can be used as a substitute. Do not use electrolytic multivitamins, because electrolytic multivitamins can decompose and ionize in aqueous solution, coagulate protein, and destroy the potency of the vaccine. Note that antibiotics and electrolytic multivitamins should not be added to the vaccine diluent. Antibiotics can kill or inhibit bacteria but are ineffective against viruses. Adding antibiotics to the diluent can prevent bacterial infections during inoculation due to inadequate disinfection, but this practice is not entirely appropriate because some antibiotics can change the osmotic pressure or pH value of the diluent. In particular, electrolytic multivitamins can accelerate the inactivation of vaccines and viruses, thereby reducing vaccine potency.

6. Strictly control the dosage. When injecting oil-based vaccines, strictly control the injection amount. It is better to inject slightly more vaccine than less. A large amount will intensify the chicken's immune response, while a small amount will not induce immunity.

7. Firmly grasp the interval between vaccine uses. When administering the vaccine in drinking water, the drinking time should not be less than 1 hour, nor should it exceed 2 hours. In summer during high temperatures, an appropriate amount of ice cubes can be added to the water. After drinking 1/2 of the vaccine, pause for half an hour, then let them drink the remaining 1/2 of the vaccine.

8. Minimize stress as much as possible. When catching chickens for inoculation, replace the light bulbs in the chicken house with blue ones at night. Since chickens are blind to blue light, people can see the chickens, but the chickens cannot see people, so the flock will not be startled.

9. During the inoculation period, strengthen feeding and management, keep the air in the house fresh, and avoid drafts and ammonia. Add an appropriate amount of electrolytes and vitamins to the water, especially Va, Vb, and Vc. 10. Do not blindly increase the number of immunizations. Some farmers develop a panic mentality about chicken diseases, especially Newcastle disease, and vaccinate once every few days, using both inactivated and live vaccines at the same time, disrupting the chicken's immune mechanism and immune response. Such vaccination often not only fails to provide effective protection for the flock, but instead may lead to the occurrence and spread of disease.