Things to Note When Stocking River Shrimp Fry, These Points Cannot Be Ignored

Many people in daily life really enjoy eating river shrimp, because everyone knows that shrimp are high in protein and taste very delicious, so the market prospects for shrimp are currently very good. Let's take a look together below!

Things to Note When Stocking River Shrimp Fry

Paying attention to the matters of stocking river shrimp fry is the key to improving the survival rate of the stocked fry. The specific points to note are as follows:

1. Removing excess silt, sun-drying and chemical disinfection can improve the bottom substrate of the pond, sterilise and disinfect it, and eliminate enemies. Quicklime is best chosen as the pond-clearing chemical, because it can kill wild trash fish, parasites, pathogenic bacteria and other harmful organisms, and can also improve the soil and water quality. Use lump quicklime that has not been dampened, and it is best to buy it just before use. The amount used is generally around 100 kg, depending on the water level of the pond.

2. River shrimp have high requirements for water quality and cannot tolerate low-oxygen environments. They are also benthic animals with poor swimming ability, often preferring to move about on the pond bottom or along the banks. Therefore, the pond should be close to large or medium water surfaces, with ample water and fresh water quality. If conditions permit, the pH, ammonia nitrogen and nitrite of the pond water can be tested, and fry may only be put into the pond when the water meets the requirements for aquaculture. When filling with water after pond clearing or when taking in and draining water normally, use 40-60 mesh sieve silk netting for filtration to prevent harmful organisms from mixing into the pond. After filling with water, test the water 2-3 days before the river shrimp fry are put into the pond to prevent losses caused by residual chemicals.

3. River shrimp like to grow in relatively fertile water, so fertilise the water before stocking and avoid releasing fry into clear water. Fertilise the water 5-7 days before the shrimp fry are put into the pond, applying 100-200 kg of fermented organic fertiliser per mu, so that there is enough natural food when the shrimp fry enter the pond. If the pond transparency exceeds 40 cm, top-dressing must be applied to ensure the water quality is “fertile, lively, tender and refreshing”.

4. River shrimp fry put into the same shrimp pond are required to be uniform in size, robust in constitution, free of disease and injury, with complete limbs, good vitality, quick reactions and strong ability to swim against the current. Egg-bearing shrimp should be stocked all at once; never put them in multiple times. Stocking time is best chosen on cloudy and rainy days; on sunny days it should be done in the morning or evening, avoiding high temperatures and muggy heat. When stocking, increase oxygen first and then release the fry.

5. Strictly follow the principle of thin loading and fast transport. During shrimp fry transport the temperature is generally rather high, so transport should be done in the early morning or evening when temperatures are lower. For long-distance transport, an air-conditioned vehicle or added ice can be used to lower the temperature, but care must be taken to raise and lower the temperature gradually to prevent too great a temperature difference. When stocking, make sure the water temperature difference is not too large; the nylon bag can be placed in the pond for 10-15 minutes, and the fry released into the pond once the water temperature inside the bag is basically the same as that of the pond water.

Environmental Conditions for Aquaculture  

The water used for freshwater shrimp (Macrobrachium nipponense) aquaculture must meet the water quality standards for fishery waters and must be clean with sufficient oxygen. There must be no large harmful organisms in the pond. The pond water depth is 1.2-1.5 m, the bottom silt should be minimal, and the substrate should preferably be hard. Freshwater shrimp are not good swimmers and have negative phototaxis; during the day they mostly hide among dark gravel or aquatic plants, that is, they lie hidden by day and come out at night, emerging at night to seek food. They spend most of their time resting on the bottom or on attachments such as aquatic plants, and like to rest in slow-flowing shallow areas along the banks where aquatic plants grow densely. Therefore, freshwater shrimp aquaculture requires a sufficient number of attachments; aquatic plants can be planted along the pond edges or netting sheets hung. However, under artificial culture conditions, freshwater shrimp can also feed during the day.

What Food Do River Shrimp Eat  

River shrimp are omnivorous animals. At the juvenile stage they feed on plankton, while adult shrimp in natural waters mainly feed on various small benthic invertebrates, the corpses of aquatic animals, attached algae, various filamentous algae, organic debris, plant fragments and so on. Farmed river shrimp can feed on various commercial feeds, such as distillers' grains, tofu residue, soybean cake, silkworm pupae, mussel meat, wheat flour, fish meal, cooked rice and river snails, and they especially like to eat maggots. When feed is insufficient, they will even eat each other. They have negative phototaxis toward light, mostly hiding in dark places during the day and coming out at night to feed and move about. Therefore, feed is mostly applied after dark.

Living Habits of River Shrimp  

1. Macrobrachium shrimp are omnivorous aquatic animals that favour animal-based feed; in artificial culture they are mainly fed commercial feed. Their optimum growth water temperature is 18-30 degrees C. When the water temperature drops to 4 degrees C they enter the overwintering period, and when the water temperature rises above 10 degrees C their vitality strengthens and feeding gradually increases.  

2. They live a benthic life, preferring to inhabit slow-flowing areas where aquatic plants grow densely, with habitat water depths ranging from 1-2 m to 6-7 m. In summer and autumn, river shrimp seek food and reproduce in the shallow water near the banks, while in winter they move to deeper water areas to overwinter, rarely feeding or moving about.  

3. At a water temperature of around 18 degrees C, sexually mature river shrimp begin to mate and spawn; mating usually takes place only just before spawning.  

4. River shrimp are shade-loving, hiding in dark places during the day and coming out at night to move about. In the reproductive season, however, they act contrary to their usual behaviour and come out during the day to carry out mating activities; also, when feed is applied, they come out during the day to compete for food.

When farming river shrimp, we must first understand the living habits of the shrimp, and secondly master some of the farming techniques and points to note, so that the shrimp farming can be done better.