Summary of Common Reasons for Failure in Rice Field Eel Farming

Rice field eel farming is also one of the special aquaculture operations. When raised properly, the economic returns are higher than those of fish farming, so in rural aquaculture, the number of households raising rice field eels has been continuously expanding in recent years. However, among the farmers raising rice field eels, quite a few have failed, and the reasons for this are many-sided. Let's take a look together below!

Summary of Reasons for Failure in Rice Field Eel Farming

1. Buying seedlings indiscriminately. The so-called “artificially bred” seedlings or other so-called “high-quality” seedlings that many farmers buy from other places are actually collected wild seedlings, and because these seedlings undergo temporary holding and unscientific operations such as multi-stage storage and transportation, the mortality rate during farming is 90% to 100%. Therefore, when purchasing seedlings, one must carefully inspect and distinguish them. Generally, for artificial rice field eel farming, one should select high-quality seedlings locally, which is both economical and guarantees quality.

2. Not being selective about varieties. From their appearance, rice field eels include types such as dark yellow with large spots, earth red with large spots, light yellow with fine spots, and blue-gray with fine spots. Only by choosing the first two types can faster growth speed be achieved, and only then can ideal economic benefits be obtained in artificial farming.

3. Mixed culture of large and small eels. When large and small eels are mixed in the same pond, the small eels do not dare to compete for food, so their constitution weakens and they may even die. When bait is insufficient, large eels swallow small eels. Therefore, although large eels grow quickly when large and small eels are mixed, the total pond output is low.

4. Pond water too deep. Because rice field eels have no swim bladder, they cannot float and stay at will in different water layers to expose themselves to the surface to breathe air. If the pond water is too deep, rice field eels need to swim to the surface frequently to breathe, which consumes a large amount of physical energy and affects normal life and growth. For pond-raised rice field eels, depending on body size, the water depth should preferably be 5 to 20 cm, while for cage-raised eels the aquatic plants should fill the entire cage so as to provide good habitat and breathing conditions for the eels.

5. Applying manure fertilizer to the eel pond. The water body of an eel pond is small, and applying manure fertilizer very easily spoils the water quality and induces disease. Such “improving water quality” is not worth the loss.

6. Neglecting to cultivate aquatic plants. Aquatic plants can prevent heatstroke and lower the temperature for rice field eels and purify the water quality. An eel pond without aquatic plants cannot create a good ecological environment, and raising rice field eels in it is also difficult to succeed, or difficult to achieve high output and high efficiency.

7. Feeding “vegetarian” food. Some farmers feed rice field eels plant-based vegetarian food such as wheat bran, rapeseed cake, bean dregs, rice, and green vegetables. When severely hungry and lacking bait, rice field eels will also swallow a small amount, but nutritionally it cannot meet the needs of the eels' life activities, let alone growth and weight gain. Over time, it causes the eels to gradually become thin and weak and to develop disease and die. Rice field eels are bottom-dwelling, ferocious carnivorous fish, and should be fed animal feed or complete compound feed.

8. Frequently changing feed. Farmers often change the type of bait fed because bait supply is not guaranteed. Rice field eel feed should have a certain stability. If the feed type is suddenly changed, the eels find it hard to adapt and refuse to eat, which affects normal production and growth.

How to Farm Rice Field Eels  

1. Environment to note when farming rice field eels  

One should choose a place with sufficient water sources and facing the sun in all four seasons. In terms of water quality, this is the key technique in rice field eel farming. One must change the water frequently to maintain good water quality. In spring and autumn, change the water once every 3-5 days; in summer, change the water once every 1-2 days. The water depth should not be less than 10 cm, and the temperature of the injected water must not exceed 5°C, so as to avoid death caused by a sudden drop in temperature.  

2. Building an eel farming pond  

To build an eel pond, choose a place with slightly higher terrain and convenient drainage and irrigation. Build the pond mainly on a small scale, with an area of 5-20 sq m, or 30-60 sq m, and a pond depth of 80-100 cm. The pond shape should run east-west. To prevent escape, an additional pond edge can be made, with the surrounding area 30-50 cm above the ground. Where the soil is relatively hard, bricks and stones may not be needed to build the pond; if building the pond in soft soil, then bricks and stones must be used to pave the bottom, build the walls, and seal the joints with cement.  

Line the pond bottom with 30-60 cm of soil that has been sun-dried and is moderately loose and firm, so that the eels can dig holes and hide. Dig a water inlet near the water source, and leave a water outlet on the opposite side at the lower end parallel to the pond bottom. Both the inlet and outlet must have fish-blocking mesh to prevent the eels from escaping. On 1/3 of the pond surface, aquatic plants such as wild rice stem, water peanut, and wormwood can be moderately planted to provide shelter for the eels, shade them, and improve the pond environment.

Nutritional Components of Rice Field Eels  

Rice field eels are rich in multiple nutritional components such as protein, calcium, phosphorus, iron, and niacin. Their calcium and iron content ranks first among common freshwater fish. They also contain a variety of essential amino acids for the human body and unsaturated fatty acids beneficial to human health, as well as a small amount of fat, vitamin B1, vitamin B2, and other components. They are a high-protein, low-fat food.  

1. Rice field eels are rich in DHA and lecithin. These are the main components that make up the cell membranes of various human organs and tissues, and are also indispensable nutrition for brain cells.  

2. Rice field eels uniquely contain “eel essence,” which lowers blood sugar and regulates blood sugar, and they contain very little fat, making them an ideal food for diabetic patients.  

3. Rice field eels contain abundant vitamin A, which can improve eyesight and promote the metabolism of the skin and membranes.  

Medicinal Properties and Effects of Rice Field Eels  

1. Enhancing memory: Rice field eels contain abundant DHA and lecithin. Regularly taking lecithin can improve memory by 20%. Therefore, eating rice field eel meat has the effect of nourishing the brain and strengthening the body.  

2. Ideal food for diabetic patients: The special substance it contains, “eel essence,” can lower blood sugar and regulate blood sugar, and has a relatively good therapeutic effect on diabetes. In addition, it contains very little fat, so it is an ideal food for diabetic patients.  

3. Protecting eyesight: It can improve eyesight and promote the metabolism of the skin and membranes.  

4. Rice field eels are warm in nature and sweet in taste, and have effects such as replenishing qi and nourishing blood, removing rheumatism, strengthening bones and muscles, and tonifying yang. They have significant effects on lowering the concentration of cholesterol in the blood and preventing cardiovascular diseases caused by arteriosclerosis. They can also be used as an auxiliary treatment for conditions such as facial nerve paralysis, otitis media, and breast swelling and pain.

Rice field eels are very rich in nutrition, so many people like to eat them in daily life, as they are rich in nutrients. Therefore, their market prospects are quite good, but various problems are also encountered during the process of rice field eel farming. Therefore, farmers must constantly summarize and constantly develop new farming techniques.