The swim bladder is composed of connective tissue and elastic fibers and plays a role in sinking and floating. The swim bladder is connected to the esophagus by a thin tube. Goldfish can float and sink in the water by adjusting the size of the swim bladder. If the goldfish's swim bladder adjustment ability decreases or completely loses its ability to adjust, swim bladder loss will occur. The common causes of swim bladder loss are as follows:

1. Excessive obesity: The ornamental fish feeds sold on the market now are relatively fine, and there are many Aquarists can even spend a lot of money to buy high-end feed for their beloved fish. The protein and other nutritional content of this type of feed is higher than that of ordinary natural feed. If you do not pay attention to controlling the feeding amount, such pampering can easily lead to excessive nutrient intake of goldfish, leading to obesity. Too much fat in a goldfish's body can cause pressure on the swim bladder, leading to swim bladder imbalance.

2. Food change: If the goldfish eats more natural live feeds in the original breeding farm, such as blood worms, algae, water fleas, etc., and aquarists usually use food after buying goldfish and taking them home. Feed them artificial feed, such as pellet feed, flake or patch feed, etc. Although artificial feed is rich in nutrients, it is generally not as easy to digest as natural live feed. Goldfish may suffer from intestinal obstruction if their diet changes significantly. , causing the intestines to swell, thereby throwing the goldfish off balance.

3. Viral infection: Rhabdovirus infection of goldfish may also cause swim bladder loss. If the swim bladder epithelial tissue of the goldfish is inflamed and degenerated, a large amount of body fluid will accumulate in the body of the sick fish and the body cavity tube will be compressed. That will affect the regulating function of the fish bladder. Goldfish infected with rhabdovirus usually show signs of emaciation, black body color, slow reaction, head rolling downward, abdominal distension, ecchymosis on the body surface, etc., and are prone to secondary enteritis. Goldfish usually die about a week after the onset of the disease, so once If you suspect that your goldfish is infected with rhabdovirus, you must treat it promptly.

4. Changes in water temperature: Goldfish are relatively sensitive to changes in water temperature. A sudden increase or decrease in water temperature will stimulate the nerve endings of the goldfish's skin, causing imbalances in the activity of the goldfish's internal organs. In this case, goldfish will often lie on their side on the surface of the water or sink to the bottom, being too lazy to swim. Therefore, in order to avoid this situation, you must pay attention to keeping the water temperature constant when raising goldfish, and control the temperature difference between the new water and the old water below 2°C when changing the water.

5. Physiological defects: If the goldfish has fin asymmetry or missing fins during growth, including no anal fin, single fin, etc. Goldfish with left-right asymmetry of anal fins or anal fins are prone to swim bladder disease, which may even be hereditary.

6. Physiological structure: Goldfish that are too short are relatively susceptible to swim bladder loss during the overwintering period, especially hair-headed goldfish. Therefore, when selecting breeder fish, it is generally not recommended to choose goldfish that are too short as broodstock. In addition, if the angle between the caudal peduncle and the caudal fin surface of a goldfish is less than 90 degrees, such goldfish will be more likely to develop swim bladder disease as their obesity increases. In addition, goldfish with smaller tail fins are also relatively susceptible to swim bladder disease.

7. Caused by hypoxia: Water hypoxia is also one of the common reasons for goldfish to suffer from dart disease. Water hypoxia will reduce the enzyme activity in the goldfish body, causing the goldfish to lose its own balance and regulation ability, and then Causes swim bladder disease, and some goldfish with relatively good physiques will recover on their own after the dissolved oxygen level in the water increases.

The above is the editor’s analysis of the common causes of goldfish losing their swim bladder. Fish dart disease is a common disease of goldfish. Aquarists should take appropriate preventive measures for their fish according to the above causes to reduce the risk of swimming bladder loss. Incidence of fish dart disease in goldfish.