For the newly-built brick cement pool, seedlings must not be planted immediately. This is because alkaline substances (Portland cement, calcium hydroxide, etc. ) In the newly-built cement pond, the pond body must be desalted for more than 20 days before it is suitable for the growth of leeches. In addition, it is impossible to feed enough seedlings in a newly-built aquaculture pond at one time, and the feeding amount should be gradually increased after the overall environmental conditions of the aquaculture pond gradually tend to the comprehensive balance of the food chain. It is not dogmatic to think how many leeches should be put in each cubic meter of water, but should depend on the specific conditions of the aquaculture pond and the benign balance between the growth conditions of leeches.
When buying leech seedlings, we should eliminate some injured, deformed, hybrid and pathological leech seedlings. Leeches with internal injuries and injuries found after a few days of temporary feeding should also be picked out in time. If you want to have a good harvest within one year after planting, you must choose healthy leeches for more than two years as seedlings. The bigger leeches are, the stronger they are, and the higher their egg production, hatching rate and survival rate are.
Animal blood clots are leeches' favorite food, but blood clots and their fishy smell are not the only sensitive bait for leeches. Leeches are hungry, and all edible lures will devour them greedily. At the same time, blood clots may pollute the water quality without special treatment, and the cost is high, so it is not suitable for taking.
Leeches have a wide range of feeding habits, and the main bodies that promote the growth and reproduction of leeches are aquatic organisms and the food chain in aquaculture ponds, such as mollusks such as snails and their larvae, fish, insects, fleas and other organisms, aquatic mycelium algae and nutrient-rich humus. Leeches and various aquatic organisms are interdependent. As long as we pay attention to the preliminary work, often put in animal manure which has been fully fermented artificially, and add inexhaustible sunshine, water and air, we can get a virtuous circle of the food chain. Achieve good results of reducing feeding costs and optimizing the ecological environment. At the same time, as long as the food chain is properly matched, the fresher the water quality and the more dissolved oxygen, the faster the growth of zooplankton and benthos will be, and the stocking density of leeches will increase appropriately.
As an appropriate supplement to the main food chain, we can feed some artificial feeds such as livestock feed and animal blood clots. The feeding amount can be determined according to the dynamic proportional relationship between adults, seasons, physical and chemical properties of aquaculture ponds and aquaculture density. If the water temperature is between 22℃ and 27℃ in the feeding season, if the water quality is fresh, you can feed more leeches, and the feeding time can be before leeches go out for food at night, otherwise you can feed less appropriately.
The layout of aquaculture ponds should be reasonable. Besides setting up bank slopes, island beaches and planting trees, deep water areas and shallow water areas should also be set up. The advantage of this is that it can play a positive role in the process of cultivating leeches by ecological method, but there are many limitations in simply setting the water depth. Some people like to put stones, branches, etc. In the breeding pond, but this is not a good way.
The habitat of leeches varies with time, region, season and environment. For example, in the middle and lower reaches of the Yangtze River, from April, some leeches will choose shallow soil near the water to lay eggs, and enter the incubation period from May to June. During this period, it is necessary to give quiet environmental conditions at the beach slope to reduce the external influence on it. After eating, leeches mostly dig holes during the day. When its food intake is insufficient, it will temporarily live among aquatic plants or adsorb on the wall of the pond. With its sensitive sense of smell and hearing, it can quickly attack and prey at any time.
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I hope it helps you.