Pneumococcal pneumoniae that survives under extreme stress conditions
Pneumococcal pneumoniae is caused by oxidative stress induced by the host’s immune system, antibacterial, anaerobic conditions, and lack of nutrients. It forms a ‘Biofilm’ even under adverse conditions, allowing colonization and continuous survival in the host.do.
‘Biofilm’ Extracellular polymer matrix, abiotic Helps to automatically aggregate, protect, and attach bacterial cellsdo In this state, pleural pneumococcus requires only minimal nutrients, and sensitivity to chemical stressors including antibacterial agents is minimized. Absolute hibernation for maximum survivabilitybecomes Biofilm is reversibly regulated according to a given environmental condition, which means that the pleural pneumococcus At any time it can re-proliferate and produce toxins that can cause major problems for the farm.also means there is
Pleural pneumonia, prevent transmission from carrier pigs by vaccination
As seen above Pneumococcal pneumoniae, once infected on the farm, has a very strong viability, so it is not easy to eradicate it. therefore The most important thing is to block the continuous transmission through bogyun dondo.
Pleurisy is one of the major pathogens causing PRDC in growing finishers.to be. Other pathogens contributing to PRDC include Circovirus (PCV2), Mycoplasma hyopneumoniae (M.hyo), Swine Influenza (SIV), PRRS, Streptococcus, Haemophilus parasuis (Glassic disease), Pasteur. Lella multocida (PM) and others.
The pleural pneumococcal colonies formed in the respiratory tract cause damage even if their size is very small. Pleural pneumonia depends on the number of pleural pneumococcal colonies, the host’s immune status, age, and which Apx (exotoxin) is expressed. Various clinical forms, from acute infection to chronic form in which the disease persists for a long timelooks like
The most well-known symptoms of pleural pneumonia are: Severe edema, hemorrhage, necrosis, and fibrosing pleurisy in acute and acute formsIt is characterized by ‘fibrin-hemorrhagic bronchopneumonia’. It is caused by the release of toxic oxygen metabolites and inflammatory mediators by lung macrophages activated by Apx exotoxin and LPS stimulation.
With subclinical infection, potential for carrier pigsThere is this. Carrier pig is a case of infection with pleural pneumonia only in the tonsils, and refers to an infection state in which the bacteria avoid the host’s acquired immunity and remain serologically negative. It also has the ability to spread to other entities.
The chronic form is the result of an acute, subacute, or subclinical infection.may appear as It presents with adhesions, fibrous pleurisy, necrotizing detachment, or abscesses covered with fibrous connective tissue, resulting in pain in respiratory movements and decreased lung function. Symptoms persist until the age of shipment of finisher pigs. As in the case of subclinical infection, the chronic form of pigsAs a result, it is possible to carry pleurisy in the tonsils without any symptoms, and it is possible to transmit pleural pneumonia to other individuals. When another individual comes into direct or indirect contact with asymptomatic carriers, the morbidity and mortality of pleural pneumonia may increase rapidly depending on the presence or absence of prior infection of pleural pneumonia and complex infection with virus. Pleural pneumonia vaccine is essential to effectively control morbidity and mortality due to carrier pigs.to be.
‘Stress control’, one of the major triggers of pleural pneumonia, is also very important
Risk factors related to respiratory diseases in pigs mainly include piglet introduction method, farm type and size, breeding facilities, breeding density, ventilation volume, air quality, temperature and temperature deviation, direct and indirect contact, aerosol concentration in case of air transmission, interception prevention and hygiene level etc. Preventive measures should be devised taking these into account.
Pleural pneumonia, in particular, requires detailed management to reduce acute stressors. The stress hormones epinephrine and norepinephrine alter the expression of pleural pneumococcal genes, including virulence factors.Because it is known to do it.
In addition The relationship between environmental changes and the occurrence of pleural pneumonia was also confirmed in the study.This means that external factors changed the pig’s immune system and homeostasis, thereby affecting the interaction between the pig and pleural pneumococcus.
Continued on the next part…
References:
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