What should be noted when vaccinating pigs? How long should the interval be? How can vaccine immunization failure be avoided?

Vaccines refer to biological products made from various pathogenic microorganisms for preventive inoculation. They are divided into two types: live vaccines and killed vaccines.So what should be noted when vaccinating pigs? How long should the interval be? How can vaccine immunization failure be avoided?

What should be noted when vaccinating pigs?

1. Emergency measures when pigs show allergic reactions or severe fever: use epinephrine hydrochloride for intramuscular injection; this drug has the effect of strengthening the heart, raising blood pressure, and resisting shock, and is the first-choice drug for this situation. Or use norepinephrine (added to 5% glucose for intravenous injection); dexamethasone (intramuscular injection).

2. Sows may miscarry. For this situation there are two choices: one is to preserve the pregnancy, and the other is to induce labor. This should be chosen according to the specific situation, and do not blindly preserve the pregnancy. Because preserving the pregnancy may, due to fetal death in the abdomen, further cause more serious consequences such as endometritis! When preserving the pregnancy, progesterone can be chosen; when inducing labor, cloprostenol sodium can be chosen.

3. Swelling may occur at the intramuscular injection site. When this happens, do not panic. You can wait until the hard swelling is relatively large and then apply a hot compress with a towel dipped in warm water. When the swollen area matures (softens), simply use a surgical scalpel to drain it, rinse the wound with hydrogen peroxide, and spray iodine tincture for disinfection.

How long should the interval be between pig vaccinations?

Every year in spring and autumn, breeding pigs are given preventive injections of vaccines for swine fever, swine erysipelas, swine pasteurellosis, and foot-and-mouth disease. After piglets reach 30 days of age, freeze-dried attenuated swine paratyphoid vaccine is injected into the muscle at the base of the ear or given orally for immunization. After 50 days of age, preventive inoculation against swine fever, erysipelas, and pasteurellosis and injection of foot-and-mouth disease vaccine are carried out.

How can vaccine immunization failure be avoided when vaccinating pigs?

There are mainly the following situations in which disease occurs after vaccination:

1. Interference from maternal antibodies. For most viral and some bacterial severe infectious pig diseases, after sows are immunized, when piglets are immunized with the same vaccine while maternal antibody levels are relatively high, they will be affected by interference from maternal antibodies. For example, in sows with standardized swine fever immunization, the swine fever maternal antibodies acquired by newborn piglets begin to decline rapidly after lasting 28 days; porcine reproductive and respiratory syndrome maternal antibodies last 21 days. Immunizing piglets with the above vaccines within one week of birth will be severely interfered with by maternal antibodies and cannot produce the expected immune effect.

2. Non-standard immunization operations. During vaccine immunization, problems such as inaccurate injection sites, lack of disinfection, insufficient injection depth, failure to choose needle length according to pig age, failure to change needles and using one needle all the way through, and even using the flying needle method, and being unable to distinguish subcutaneous, intradermal, and intramuscular injections are relatively common, resulting in uneven or substandard antibody levels after immunization. After vaccine immunization, it cannot provide a relatively good protective effect.

3. Vaccine quality factors. Vaccine quality directly affects the success or failure of immunization. There are as many as more than 10 kinds of vaccines commonly used for pigs. Links such as the storage, transportation, dilution, and use of vaccines can also cause vaccine deterioration and a decline in potency, leading to immunization failure.

4. The impact of immunosuppression. Immunosuppression is when, under the action of external factors, immune tissues and organs are damaged, the ability of immune cells to present antigens is blocked and inhibited, and the body's immune response is incomplete. Under infection with low-pathogenicity and attenuated pathogens, disease can be triggered. There are many factors causing immunosuppression in the body, such as mycotoxins, heavy metals, radioactive radiation, stress factors, incomplete nutrition, vitamin deficiency, as well as porcine reproductive and respiratory syndrome and porcine circovirus disease. At present, immunosuppression commonly exists latently in pig herds, and only the degree of immunosuppression differs among different pig herds. Pig farms should attach great importance to the phenomenon of immunosuppression and do a good job in corresponding prevention and control.

5. Feeding and management factors. Incomplete nutrition, inadequate facilities and equipment, and a poor living environment for the pig herd mean that the nutrients needed for growth cannot be satisfied and the body's health level cannot be guaranteed. Therefore, after immunization, the antibody level of the pig herd cannot reach the expected level and protective capacity, leading to immunization failure in the pig herd, which can easily trigger sudden major animal epidemics.

6. Before vaccine injection, the disease is in the incubation period, and disease occurs after immunization.

To prevent immunization failure, the following aspects of work should be done well:

1. Scientific feeding and management to improve health levels. Pig farms should improve the health level of the pig herd around scientific feeding and management measures such as self-breeding and self-raising, complete-price feed feeding, programmed immunization, institutionalized disinfection, scientific medication, and health-care-based epidemic prevention.

2. Combine immunization with monitoring to avoid blind immunization. Traditional pig farms (households) believe that once the vaccine is injected, everything is fine, and they are resistant to immunization inoculation and sampling monitoring. Immunization and monitoring complement each other. Through monitoring, the time for the first immunization of piglets can be determined, the immunization effect can be evaluated according to monitoring results, the supplementary immunization time can be formulated, and monitoring can be used to predict the potential threat of some epidemics. Tracking and monitoring of the pig herd at different stages is the basis for scientifically and reasonably formulating immunization programs. It can avoid the blindness of immunization and ensure the timeliness of immunization. Scientific monitoring can avoid interference from maternal antibodies, discover hidden infections of pathogenic microorganisms, avoid mutual interference between vaccines, and improve immunization quality.

3. Avoid immunosuppression and eliminate potential hidden dangers. The phenomenon of immunosuppression in pig herds is widespread and has gradually become an important factor affecting pig herd health. Immunosuppression is an invisible killer in which the body destroys the resistance of the immune system, but it can also be avoided and controlled. Use feed produced by legitimate manufacturers and control feed mildew factors; monitor water sources, heavy metal content in feed, and pollution from radioactive rays and other physical factors; eliminate pigs and pig herds with pathogenic immunosuppression and control pathogenic immunosuppression factors; feed complete-price feed with different nutritional values according to different ages to improve immunity; strengthen disease monitoring and reduce stress such as group transfer, eliminating immunosuppression caused by disease and stress.

4. Ensure vaccine quality and quantity to ensure immunization effect. Inferior vaccine quality and non-standard operations are important causes of immunization failure. Choose vaccines produced by legitimate enterprises or government-procured vaccines, use matching diluents and the prescribed dilution degree for vaccine dilution, and use them up within the prescribed time after dilution; otherwise they can no longer be used. When injecting vaccines, immunize according to the immunization dose, injection site, and injection method stated in the instructions. Stop using antibiotics for about 5 days before and after immunization to ensure that bacterial vaccines are not cleared after immunization; when vaccinating, choose needles of different specifications according to the size of the pig, and avoid missed vaccinations, ensuring the quality and effect of vaccine immunization and reducing the occurrence of immunization failure.