How to prevent and control red and white plastron disease in soft-shelled turtles? Detailed explanation of causes and prevention methods

Red and white plastron disease in soft-shelled turtles (commonly known as red plastron and white plastron disease) has been a relatively serious turtle disease in China in recent years, and so far there is still no ideal treatment method. However, through efforts in various aspects, the main pathogens and disease onset conditions of red and white plastron disease have basically been identified, and breakthrough progress has been made in prevention, especially in research on disease prevention with Chinese herbal medicines and immune vaccines, laying a foundation for controlling the occurrence of red and white plastron disease in the future. Based on relevant domestic research and my own practice, the author introduces the occurrence and prevention of red and white plastron disease as follows, for reference and application by interested parties.

Symptoms of red and white plastron disease

1. Behavioral changes. Sudden or long-term cessation of feeding is a typical symptom of red and white plastron disease, and the reduction in food intake is usually above 50%. After onset, sick turtles mostly drift and swim at the pond edge or gather in groups. Most sick turtles stretch their heads and necks out of the water and then lean back, opening their mouths as if gasping. Some bleed from the nostrils or produce bubbles. In severe cases, there are obvious neurological symptoms, so they are unusually sensitive to environmental changes. At the slightest disturbance, they quickly flee, and soon after dive back to the pond edge and die.

2. External symptoms. There are no infectious lesions on the body surface of sick turtles. A round black shadow patch can be seen in the middle of the back, commonly known as the "black cover." When sick turtles die, the head and neck become soft and extend outside the body. Some, due to absorbing too much water, become swollen all over and rigid. Newly dead sick turtles have their heads facing downward, and when lifted, blood or water drips from the mouth and nose. Some have a turbid red abdomen (red plastron), while others are pale white (white plastron). Most have the male reproductive organ protruding outside the body, and some have swollen necks.

Handling and control after onset

Because the occurrence of red and white plastron disease is explosive and develops very quickly, handling and control should be based on the specific circumstances at the time. Generally, it is divided into the following situations: First, if the disease has been present for several days, food intake has already dropped by more than half, or the turtles do not eat at all, and the weather conditions show no trend of improvement, with continuous low temperature and rain, the pond should be cleared as soon as possible and the turtles caught and sold to reduce losses. After clearing them out, thoroughly disinfect and stock some fish, because under such circumstances it is already difficult to control the development of the disease by administering medication in feed. Second, if the weather alternates between clear and rainy, the water temperature is unstable, the disease has not yet become an outbreak in the early stage, the turtles' food intake has not yet dropped by more than half, and the weather shows no stable trend of improvement, then if there is a sunlight greenhouse, the turtles should be caught and moved into the greenhouse for intensive feeding, and the drug Bingduqing should be added to the feed and fed for 5 days, which can control the development of the disease. If there is no sunlight greenhouse, and the disease occurs in intensive small cement ponds, a simple shed can be built over the pond to raise the temperature and stimulate feeding, and the effect is also quite good. Third, if the disease occurs in large outdoor mud ponds that are difficult to harvest from, and the condition is severe and explosive, with feeding basically stopped, while the weather shows no trend of improvement, then "protection" measures should be adopted. The specific methods are: first, disinfect the pond water with disinfectants such as chlorine dioxide every 6 days; second, exchange water appropriately. If the pond water is relatively turbid, exchange 1/5 of the original pond water every 3-4 days to maintain good water quality. After exchanging water, some quicklime should be properly splashed, generally to a concentration of 25×10-6 in the pond water.

Avoid drastic actions such as large water exchanges, heavy chemical application, and heavy application of quicklime. At the same time, patrol the pond twice a day and promptly remove dead turtles for long-distance deep burial or chemical treatment. Third, when the weather slightly improves and the water temperature rises above 26°C, purchase some good-quality, fresh marine fish, freshwater fish, or fresh pork liver, cut them into suitably sized small pieces, and feed them at multiple points in the pond to attract feeding, until there is complete improvement, then feed artificial feed again.

It is worth pointing out that in some places, after turtles become seriously ill, high doses of antibiotics and chemicals are administered. If the turtles do not eat, this causes waste; if they eat a little, the drug damage instead accelerates the death of sick turtles. Because many antibiotics and chemicals have side effects that damage the liver and kidneys of turtles, feeding should also focus on Chinese herbal medicines or additives that improve the body's immunity and nutrition, such as Astragalus, licorice, Isatis root, honeysuckle, and other Chinese herbal medicines containing polysaccharides and detoxifying alkaloids, as well as nutrients such as multivitamins, to enhance the disease resistance of turtles.