How can fish diseases be prevented during tilapia farming?

In tilapia farming, nothing is more worrying than fish getting sick, because if it is not treated in time, it will cause serious economic losses. So how can fish diseases be prevented in tilapia farming?

1. Common tilapia fish diseases and their prevention and treatment

1. Bacterial enteritis

Fish suffering from bacterial enteritis have a darkened body, stop feeding, respond slowly, have abdominal cavities filled with pale yellow ascites, and show symptoms such as red and swollen anus. The survival rate of this disease is 10%. The cause of the disease is the use of poor-quality feed, which reduces the disease resistance of the fish and allows bacteria to multiply in large numbers.

The prevention method is to thoroughly disinfect the pond bottom with quicklime before stocking the fingerlings, and feed with allicin mixed into the feed at 8g·kg-1, twice a day, for 4 to 6d continuously.

2. Gill rot disease

Symptoms include slow swimming, congestion and inflammation of the skin on the inner surface of the operculum of diseased fish, swelling of the gill filaments, and even shedding of the gill lamellae. The higher the temperature, the more likely it is to break out, with a survival rate of 20%.

The prevention method is to alternately splash quicklime over the whole pond once every half month, keeping the pond water pH at around 8.

2. Points to note in the daily management of tilapia

1. Water quality regulation

2d before stocking the fingerlings, after the toxicity of the pond has disappeared, inject an appropriate amount of EM bacterial liquid or photosynthetic bacteria into the pond water, and add another injection every 25d, paying attention to activation treatment during this process.

Add new water once every 15d, and regulate water quality through regular water addition, drainage, and water replacement, thereby ensuring relatively stable and clean water quality.

2. Water body fertilization

Fertilize frequently, keeping water transparency at 25 to 30cm, and determine the frequency and amount of fertilization according to the pond water temperature, weather conditions, and pond water color. If the pond water temperature is low, reduce the frequency and increase the amount of fertilizer; if the pond water temperature is high, reduce the amount of fertilizer and increase the frequency; on cloudy and rainy days, reduce the frequency and amount of fertilization, or even do not fertilize; when the weather is clear, increase the frequency and amount of fertilization; if the water color is oily green or tea brown, reduce the frequency and amount of fertilization, or even do not fertilize; if the water color is light, increase fertilization.

3. Artificial immunization

Use artificial immunization such as injection, immersion, spraying, and oral vaccines for fish to strengthen the prevention of tilapia diseases under high temperatures. However, vaccines for disease prevention are still in the research and development stage for the control of tilapia diseases, and production application at this stage is still relatively limited.