What are the symptoms of porcine reproductive and respiratory syndrome?

Porcine reproductive and respiratory syndrome was once called “mysterious swine disease” and “new swine disease”, etc. In China, this disease is classified as a Class II infectious disease. If this disease is not effectively controlled in the early stage, it can easily cause large-scale infection. Therefore, many farmers pay great attention to porcine reproductive and respiratory syndrome. So what are the symptoms of porcine reproductive and respiratory syndrome?

1. Symptoms of onset

In the early stage, pigs infected with porcine reproductive and respiratory syndrome mainly show listlessness, decreased appetite, reluctance to move, and lying in the pigpen all day. Afterwards, the pig's body temperature rises, and as the condition worsens, the pig's body temperature remains at a relatively high level, and in severe cases the temperature can reach above 40°C. In the later stage of the disease, the pig's head becomes swollen, which is very obvious compared with normal pigs. At the same time, blue-purple patches also appear on the pig's body, and the area continues to expand.

2. Affected groups and timing

The onset of porcine reproductive and respiratory syndrome is mainly concentrated in three time periods: first, the three months after a sow becomes pregnant. During this stage, the pig fetuses in the sow's body are developing rapidly, and the mother's resistance continuously declines, making her very susceptible to porcine reproductive and respiratory syndrome; second, piglets just 1—2 months after birth. During this period, the piglets' immune systems are very fragile, and if rearing methods are improper, they are very likely to become infected with porcine reproductive and respiratory syndrome; third, the onset situation in boars. The incidence rate in boars is relatively low, mostly concentrated when boars are 150—200 jin. At this time, more attention should be paid to the condition of boars and preventive work should be done well.

3. Causes of onset

The causes of porcine reproductive and respiratory syndrome can generally be divided into two types: one is caused by external factors, and the other is caused by improper rearing methods. External factors mostly refer to infection caused by newly introduced pigs carrying the virus, or the porcine reproductive and respiratory syndrome virus from nearby pig farms being transmitted to one's own pig farm through the air; improper rearing methods mainly refer to pig farm hygiene not meeting standards, disinfection not being thorough, etc. These may all be causes of the onset of porcine reproductive and respiratory syndrome.

At present, the mortality rate of porcine reproductive and respiratory syndrome is very high. If it is discovered that a pig has been infected with this disease, the entire pig farm should be disinfected immediately and preventive work should be done well to avoid large-scale infection. Porcine reproductive and respiratory syndrome has many symptoms, and special attention should be paid during the periods when it is prone to occur, so that it can be handled in time.