On the issue of water quality in aquaculture of aquatic products

6 answers

Anonymous users2024-02-15

I'll give you some information for you to see.
Anonymous users2024-02-14

Summary. The difference between aquatic products and farmed aquatic products is that aquatic products refer to those wild aquatic products that grow freely, such as wild sea bass, wild crucian carp, etc.

The difference between aquatic products and farmed aquatic products is that aquatic products refer to those wild aquatic products that grow freely, such as wild sea bass, wild crucian carp, etc.

Aquaculture type: according to the salt content of the water can be divided into freshwater aquaculture, marine aquaculture, according to the difference of aquaculture waters can be divided into pond aquaculture, rice field cultivation and cherry breeding, high brigade reservoir aquaculture, etc., according to the breeding method can be divided into tidal flat aquaculture, shallow sea aquaculture, etc.

The main freshwater aquaculture species: fish include yellow eel, loach, celery crucian carp, grass carp, etc., crustaceans include small slap lobster, hairy crab, etc., and other species include snails, turtles, etc.

The main aquaculture species of seawater: algae including seaweed, kelp, etc., shellfish including oysters, scallops, etc., fish including barracuda, perch, grouper, etc., crustaceans including tiger crab, vannamei shrimp, etc.
Anonymous users2024-02-13

1. Dissolved oxygen: Like all animals, most aquatic animals must survive under aerobic conditions, and hypoxia can make them float their heads, and in severe cases, they will be killed by flooding. Generally speaking, the dissolved oxygen of the breeding (nursery) water body should be kept at 5-8 mg l, at least above 4 mg l, not less than 3 mg l, and not less than 4 mg l in the later stage of high-density intensive culture.

In addition, fish, shrimp and crabs, especially seedlings, with too much dissolved oxygen are also very susceptible to bubble disease.

2. The pH value is between, not higher. Mariculture in between, the daily difference shall not be greater than.

3. The content of ammonia nitrogen (NH3 N) should be controlled below below. The toxicity of ammonia nitrogen is related to the pH value of water, and when the pH value is high, ammonia nitrogen can be converted into molecular ammonia that is very toxic to fish and shrimp, inhibiting the growth of fish and shrimp, damaging gill tissue, and aggravating fish diseases. At lethal concentrations, molecular ammonia can cause acute poisoning and death of aquatic animals.

Fish and shrimp will show severe anxiety in the event of acute ammonia poisoning. Because at this concentration, the pH value of the water quality is alkaline and has strong irritation, which increases the mucus on the body surface of fish and shrimp, congests the body surface, and bleeds from the gills and fins at the base. Fish swim on the surface of the water, protruding eyeballs and struggling with their mouths open before dying.

4. Nitrite (NO2-N) is quite toxic to fish, shrimp and crab, and if the content of shrimp ponds exceeds it, it can cause serious harm. When the nitrite concentration in the water is reached, some metabolic functions of fish, shrimp and crab are abnormal, and physical strength is exhausted.

5. The concentration of hydrogen sulfide should be strictly controlled below when it is exceeded, which will cause fish, shrimp, crab and turtle to have difficulty breathing, and even poisoning and death.
Anonymous users2024-02-12

According to the formal requirements to comply with GB 11607-1989, but now in addition to the factory farm can meet this standard, other water bodies are difficult to meet this standard, under normal circumstances, as long as the water is not seriously polluted can be farmed, the detection method is also simple, put some fish and shrimp in the water body, after a period of time can be farmed, dead will not work.
Anonymous users2024-02-11

The main problems currently faced in aquaculture:

First, the contradiction between industrial development and resources and environment has intensified. The failure to get rid of industrial development is based on the large number of possession, dependence and even destruction of resources, environment and other productive factors, and ecological security has become an important factor restricting the development of aquaculture. External water scarcity and pollution restrict aquaculture, and aquaculture sewage affects the external environment.

Second, breeding diseases occur frequently, causing large economic losses. The traditional breeding methods and management are not suitable for modern fisheries, blindly pursuing high yields, resulting in frequent diseases, and the output and efficiency of aquaculture have been greatly affected, which has a significant impact on the healthy development of aquaculture. Unreasonable and non-standard drug use leads to drug residues in aquaculture products, affecting the quality and safety of aquatic products, consumption and export, and restricting the development of aquaculture industry.

Third, the basic engineering facilities are weak, and the degree of intensification needs to be improved urgently. The breeding facilities are backward and the technical content is low, which has seriously failed to meet the requirements of modern aquatic development, and has restricted the healthy development of aquatic products in China. China's pond aquaculture, basically follow the structure and layout of the traditional aquaculture method, only has to provide fish growth space and basic inlet and drainage functions, pond modernization, engineering, facilities level is low.

Fourth, the research on the selection and breeding of improved varieties is lagging behind. There are very few artificially selected varieties, and the main cultured species such as grass silver carp, which accounts for more than 70% of the total aquaculture production, still rely on wild species that have not been selected and improved.

Fifth, there is a large gap between aquaculture production and feed demand. In aquaculture, about 30 million tonnes are fed as feed raw materials each year, and extensive aquaculture leads to waste of resources and environmental degradation. For example, the aquaculture output of grass carp is nearly 5.1 million tons, and the demand for feed is 7.6 million tons; The production of carp aquaculture is nearly 3 million tons, and the demand for feed is 4.5 million tons; The production of crucian carp aquaculture is nearly 2.6 million tons, and the demand for feed is 3.9 million tons; The aquaculture output of bream is nearly 730,000 tons, and the demand for feed is 1.1 million tons; The production of herring aquaculture is about 530,000 tons, and the demand for feed is 790,000 tons.

Sixth, the space for aquaculture development has been squeezed. The economic and social development and the expansion of construction land have caused the water surface and tidal flats to be encroached upon and occupied, the inland water surface that can be cultivated has been reduced, and the development and utilization of aquaculture water surface have encountered difficulties, which have led to the protection of fishermen's rights and interests and the resettlement of production and life.

Seventh, quality safety and market supervision issues. Lack of scientific and technological innovation capabilities, lagging research and development of new alternative fishery drugs and vaccines, germplasm degradation, backward feed technology, etc., affect quality and safety; It is difficult to control the external environmental pollution in the open breeding site, resulting in excessive toxic and harmful substances in aquatic products; The means of law enforcement and supervision are limited, and it is difficult to fully supervise in the face of decentralized breeding and product circulation and distribution; The lack of quality standards and the lack of cohesion in the standards of importing countries have made China's aquatic products suffer unfair treatment in the export.

Eighth, the level of aquatic product processing technology is not high, and the processing capacity is very limited. Aquatic product processing technology, especially bulk product processing and comprehensive utilization technology, is not mature and matching, which directly affects the rapid development of aquaculture industry.
Anonymous users2024-02-10

Aquaculture exists in China.

Source of the problem 1: Environmental pollution is becoming more and more serious. As a result, the consumption of aquatic aquaculture is not du

There are many factors in safety and environmental pollution, and the large use of agricultural chemicals such as fertilizers, pesticides, veterinary drugs, and production regulators plays a very important role in the sustainable and rapid development of China's agriculture. 2 Drug abuse in the breeding process. Leads to aquaculture.