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How to write a paper on the causes of animal immunization failure
Cause analysis of animal immune failure

Animal immunization is to prevent and control the occurrence of animal infectious diseases.

Effective way. Only by selecting high-quality vaccines and doing a good job in transportation and protection.

Only the storage conditions and the correct use methods can produce a good immune preparation.

Preventive effect, ensuring animal health. At present, in animal husbandry production, due to

Due to various factors, animal immunity fails, leading to animal diseases.

Diseases have brought huge economic losses to aquaculture. According to years of research

From practical experience, the factors of animal immune failure are summarized as follows.

1 animal's own factors

Immune failure caused by animals' own factors: including low immunity

Effect of maternal antibody, immunosuppression, stress response, feed

Poisoning or something.

1. 1 low immunity.

Immunity is the ability of the body to respond to antigens, which will affect.

Improve the immunity of the vaccine. Congenital immune organ hypoplasia, immunity

System defects, such as hypoplasia of spleen, bursa of fabricius and thymus, lack of

T, B lymphocytes and macrophages will be affected after vaccination.

The immunity of the vaccine can't reach the expected immune effect.

1.2 maternal antibody

In recent years, various vaccines have been widely used in livestock and poultry breeding, which makes young livestock and poultry

The level of maternal antibody increased significantly. If the maternal antibody is at a high level

When vaccination is carried out in the horizontal period, the maternal antibody will neutralize the vaccine components.

And inhibit its proliferation in animals, so that the expected results cannot be obtained.

Immune effect, and even lead to immune failure. Some young domestic animals and poultry are susceptible.

Diseases need high maternal antibody protection, such as premature use of live vaccine.

Can cause immune failure, such as Newcastle disease, infectious bursal disease,

Classical swine fever, infectious gastroenteritis, epidemic diarrhea, piglet yellow.

Diarrhea, rotavirus, porcine contagious pleuropneumonia, porcine atrophic nose

Inflammation, chicken infectious anemia, etc. Only according to the growth and decline of maternal antibodies,

Timely vaccination can effectively achieve the expected immune effect.

1.3 immunosuppression

Immunosuppressive pathogen infection will affect the immune system.

Affected to varying degrees, thus inhibiting the response of animal immune system to the epidemic.

The immune response ability of vaccine reduces the protective power of vaccine, such as infectivity.

Bursal disease, Marek's disease, chicken coccidiosis, chicken infectious anemia.

Keywords blood, avian leukemia, mycoplasma hyopneumoniae, porcine blue ear disease, porcine cirrhosis

Circovirus type II, Eperythrozoonosis, canine fever, etc. Will be damaged.

Immunity to specific pathogens leads to immunosuppression. Congenital dysplasia or

Malnutrition can also lead to decreased resistance, which can be treated after immunization.

Can cause serious reactions or lead to immune failure.

1.4 pressure reaction

Bad feeding environment, such as hot, cold and crowded livestock and poultry houses,

Humidity, lack of ventilation and abrupt climate change put animals in a state of stress.

State, leading to the decline of vaccine immune efficacy. In addition, hunger, changing groups, silence.

Stimulation of cutting, sudden refueling, long-distance transportation and other adverse factors.

It will cause stress reaction and cause immune failure.

1.5 Toxic substances in feed

Under the condition of high temperature and high humidity, the feed is moldy and moldy.

Bacteria that release mycotoxins, especially Aspergillus flavus and ochratoxin.

Lymphocytosis, even if the number is small, can cause lymphocyte toxicity.

Sex and inhibition of humoral immunity and cellular immunity.

Two factors of vaccine

Immune failure caused by vaccine factors, including serotypes and epidemic diseases.

The quality of vaccines, the mutual interference of vaccines and so on.

2. 1 serotype

Foot-and-mouth disease, influenza, chicken infectious bronchitis, etc.

Species serotype. Although there are many serotypes, they cannot provide the intersection between them.

Cross-protection cannot produce cross-immunity, so the vaccine strain is selected.

Serotypes should be consistent with the serotypes of strains prevalent in this area and field.

Otherwise, the ideal immune effect will not be achieved.

2.2 vaccine quality

The key of attenuated vaccine is immunogenicity and toxicity, while inactivated vaccine

The key is the effective virus content, so the use and purchase of vaccines should be selected.

Use enterprises that have passed the GMP certification of the Ministry of Agriculture, and do not use sources.

Ming, unclear identification, illegal production and illegal import of vaccines, otherwise

Will lead to immune failure.

2.3 vaccines interfere with each other

The replication of some pathogens will affect the proliferation of other pathogens. different

The vaccine is inoculated at the same time or in the same way, and the vaccine is in the animal.

Will interfere with each other, affect each other's replication and immune response, resulting in

Immune failure, such as porcine blue ear disease vaccine, will affect the live swine fever vaccine.

Immune response, Newcastle disease vaccine and transmissible vaccine used together or

Too short an interval will lead to immune failure.

3 factors of transportation and preservation

Different vaccine strains and dosage forms have different storage temperatures because

This should be saved according to the instructions. Care should be taken to keep the temperature when storing vaccines.

Stable, try to avoid high and low temperatures and avoid repeated freezing.

Melt, otherwise it will reduce vitality and titer.

Vaccine transportation must be low temperature and fast, avoiding high temperature and direct sunlight.

Shoot, conditional use of refrigerated trucks, unconditional use of refrigerated containers.

Put ice on it.

The vaccine cannot exceed the effective shelf life, and the packaging is damaged and lost.

Vaccinations with empty bottles, loose caps and discolorations cannot be used.

Four factors of immunization program

It is necessary to formulate scientific and reasonable immunization procedures. Immunization plan

Unreasonable will lead to immune failure.