A Detailed Explanation of Feed Formulas for Silver Carp Farming

I think silver carp is fairly common in daily life, and everyone eats it often. As China's aquaculture industry has been developing very well in recent years, especially in the area of farmed fish, fish farming has a relatively low threshold and low investment cost, making it very suitable for rural farming.

Feed Formulas for Silver Carp in Silver Carp Farming

Compound feed is a powdered or granular feed made by mixing various feeds according to a certain formula based on the nutritional needs of the fish. If vitamins and trace element additives are used in the formula, it is called a complete compound feed. Compound feed can bring into play the nutritional complementary effects of various feeds, better meet the nutritional needs of fish growth and development, promote fish growth and save feed resources. Practice has proved that silver carp can adapt well to compound feed, and feeding silver carp with compound feed generally achieves good results, so the use of compound feed should be promoted as much as possible.

1. Nutritional needs of silver carp: Silver carp farming has a long history in China. Traditional farming mainly used fertilization to cultivate plankton as feed for silver carp. In recent years, compound feed has begun to be used, but there is still insufficient research on the nutritional needs of silver carp.

2. Formula of compound feed for silver carp: Because silver carp can obtain a certain amount of natural food in water, its nutrition does not come entirely from artificial feed, and its requirements for the completeness of feed are relatively low. Under the current situation of insufficient research on the nutritional needs of silver carp, the formula of compound feed for silver carp is quite uncertain.

Practice has proved that in waters where silver carp is the main species, producing silver carp compound feed by referring to the feed formula for grass carp can achieve good farming results. In waters where silver carp is the main species, using pond mixed-fish feed produced by feed mills also gives good farming results.

Living Habits of Silver Carp  

1. Feeding habits: Silver carp is a mid-upper layer fish and feeds on plankton throughout its life. At the fry stage, it mainly eats zooplankton. When it grows to more than 1.5 cm, it gradually shifts to eating phytoplankton, and it likes to eat the feces of grass carp and the chicken and cow manure that is applied. It is very interested in sour foods and also has a good appetite for distillers' grains feed. Its food has obvious seasonality. In spring and autumn, in addition to plankton, it also eats a large amount of detritus-type feed. In summer, the lower the water level, the greater its food intake. In winter, it eats little and moves little during overwintering.  

2. Water temperature: Silver carp likes high temperatures, and the most suitable water temperature is 23-32°C. In hot summer, silver carp has the strongest appetite. It is lively in temperament and likes to jump, and has the habit of swimming upstream, but its movements are not very agile and it is rather clumsy. Silver carp likes fertilized water, and individuals of similar size often gather and swim in schools to the middle and upper layers of the water, especially in clear water areas with relatively fertile water quality. It is timid and afraid of disturbance, and its ability to tolerate low oxygen is extremely poor. When there is insufficient oxygen in the water, it immediately comes to the surface, and some soon die.  

3. Reproduction: Silver carp grows fast and has high yield. Its sexual maturity age is 1-2 years earlier than that of grass carp, and mature individuals are also smaller. Generally, female fish above 3 kg can reach maturity. A female fish of about 5 kg has a relative fecundity of about 40,000-50,000 eggs/kg body weight. It spawns from April to May each year, and the eggs are floating eggs. Under pond culture conditions, if feed is sufficient, the fish of the year can grow to 500-800 g, three-year-old fish can reach 3-4 kg in body weight, and in natural rivers they can reach 30-40 kg.

Farming Techniques for Silver Carp  

1. Selection and retention of brood fish: Select natural original stock for brood fish, requiring health and good gonadal development. The individual weight of silver carp should be above 6 kg, bighead carp above 10 kg, black carp above 15 kg, and grass carp above 8 kg. The annual replacement rate of brood fish should reach about 10%.  

2. Clearing and preparing the fish pond: Brood fish ponds should have convenient irrigation and drainage. The bottom of silver carp and bighead carp ponds may have 20 cm of mud, while the bottom of black carp and grass carp ponds should contain little or no mud. The area should be 1-5 mu, and the water depth should be about 1.5 m. The pond should be cleared before stocking.  

3. Mixed stocking: The ratio of female to male brood fish of silver carp, bighead carp, black carp, and grass carp is generally preferably 1:1-1.5. At the same time, 8-10 mandarin fish and about 150 bighead carp per mu should be stocked to control the breeding of wild trash fish and large zooplankton.  

4. Feeding management: Before stocking, 500-700 kg of decomposed organic fertilizer should be applied per mu to silver carp and bighead carp brood fish ponds to cultivate plankton, and appropriate fertilization should continue afterward. In addition, on clear and warm days, soybean cake slurry should be fed to promote gonadal development.  

5. Early induced spawning: When the female fish's abdomen is enlarged and the genital pore is relaxed, spawning can be induced. Generally, female fish are injected with 1000 international units of chorionic gonadotropin per kg body weight, or 40-50 micrograms of LRH-A, and male fish receive half the dose.  

6. Hatching management: Hatching water should be filtered with a filter net to prevent floating matter and wild trash fish from entering. Before each hatching, clean the hatching jars and hatching troughs, provide a suitable water flow rate during hatching, and frequently turn over the water body to check whether eggs or fry have accumulated in the bottom corners, so as to maintain water quality.

What Food Silver Carp Eats  

1. Silver carp is a typical filter-feeding fish. It filters plankton from the water by means of the special structure of its gills and feeds on plankton throughout its life. At the fry stage, it mainly eats zooplankton. When it grows to more than 1.5 cm, it gradually shifts to eating phytoplankton, and it likes to eat the feces of grass carp and the chicken and cow manure that is applied. It also eats soybean milk, soybean residue powder, bran, and rice bran, and it even more likes to eat artificial micro-pellet compound feed.  

2. Silver carp is very interested in sour foods and also has a good appetite for distillers' grains feed. Silver carp likes to eat decaying food and is often stocked together with grass carp, with silver carp eating the feces of grass carp, hence the saying that one grass carp supports three silver carp.  

3. Silver carp's food has obvious seasonality. In spring and autumn, in addition to plankton, it also eats a large amount of detritus-type feed. In summer, the lower the water level, the greater its food intake. In winter, it eats little and moves little during overwintering.

From the above analysis, we can know that the first task in farming silver carp is the feed formula. Using reasonable feed can greatly increase fish yield and also shorten its farming cycle, but feed should not be given blindly. It should be fed appropriately on the principle of saving costs.