Overview of porcine parvovirus (PPV)

Pathogenic characteristics

Porcine parvovirus (PPV) is a kind of important virus, parvovirus genera belong to small virus, the virus particle without posterior capsule, about 20 to 25 nm in diameter, genome into a single linear DNA molecules. PPV has stronger ability to resist the external environment, the resistance to heat, acid, fat solvents and organic solvent, which enables the virus to survive and spread in a variety of conditions.

epidemic

PPV are distributed worldwide, especially in pig populated areas. The virus to infect pigs usually exists in pig farms, stillbirth, piglet and produced by waste of uterus had a high degree of the virus, and take poison from the pig pigs may take drug detoxification time is very long or even a lifetime.

Route of Transmission

Mainly through PPV infection pig feces, urine secretion eduction body outside, and transmitted through the digestive tract, respiratory tract, etc. The virus can also through contaminated feed, environment, and vertical transmission to the fetus via the placenta. In addition, such as rats and mice may also as a medium of mechanical transmission.

clinical signs and symptoms

PPV infection is the main clinical symptoms of reproductive dysfunction, such as abortion, stillbirth and mummy tire production. Especially the first-timer sows, and the pigs, pig, boars may have no obvious clinical symptoms or does not show any clinical symptoms.

Pathological changes

The pathological changes of the infected pigs there is no visible to the naked eye, and when abortion may see a slight changes of endometritis and part of the placenta. Produced by piglets may present different degree of pathological changes, such as dead, weak and mummy foetus. Autopsy dead piglet visible subcutaneous congestion, edema or bleeding, inside body cavity effusion, liver, spleen and kidney degeneration.

Diagnostic methods

PPV diagnosis based primarily on epidemiological investigation, clinical symptoms and pathological changes were preliminary diagnosis, diagnosis depends on laboratory diagnosis, such as virus isolation and identification, serological diagnosis, etc. Serological diagnosis methods including blood clotting and blood clotting inhibition test and latex agglutination test, immunofluorescence test, etc.

Prevention and control measures

There is no specific treatment for PPV, therefore, more important is to do a good job of immune prevention, including vaccination and environmental disinfection. Suggest a first-timer sows in 5 ~ 6 months first, again after 2 ~ 4 weeks to strengthen the immune to breeding; Multiparity sows in 1 months or so before mating once immune; The sow is not recommended during pregnancy immune; Boars first, when eight months after the spring and autumn period and the various immune once a year.

conclusion

The pig parvovirus disease is a disorder caused by small pig virus reproduction, pose a major threat to healthy development of pig industry. The virus has wide distribution and strong resistance to environmental capacity, and transmission diversity, complex clinical symptoms and pathological changes. The current lack of effective treatments, rely mainly on prevention measures, including reasonable planning immunization program and implement strict biosecurity measures. In the future, with the progress of science and technology, we are looking forward to have more in-depth studies of PPV, provide a new solution to control and eliminate the disease.