Growing black carp fish in aquaculture

 

Black carp fish is a Far Eastern invader, one of the interesting objects for aquaculture, which has its own niches when grown in pasture aquaculture. It is worth taking a closer look at what kind of fish black carp is and where it can be successfully grown.

Content

• What kind of fish is black carp?
• What does black cupid look like?
• What does black carp eat?
• Stocking density of black carp when grown in a pond
• Benefits of rearing black carp in aquaculture
• Breeding black carp in fish farming
• How to carry out factory reproduction of black carp
• Incubation of eggs and maintenance of black carp larvae
• Raising black carp larvae
• Raising fingerlings

 

What kind of fish is black carp?

Simultaneously with herbivorous fish - grass carp, white and bighead carp - in 1961-1962. The mollusk eater Mylopharyngodon piceus Richardson - black carp - was imported from the rivers of the Far East (PRC).

Currently, you can meet black carp in Central Asia (Uzbekistan), Kazakhstan, southern Russia, as well as in the middle zone. Black carp were introduced into the water bodies of Belarus, first in the Minsk and Brest regions, and then further in the II and III fish farming zones of Belarus. Black carp is found in many reservoirs of Ukraine and Moldova.

What does black cupid look like?

This is a large carp fish (length 130 m and weight 50 kg), the body of which is covered with large scales, with a black back and a lighter belly.

Black carp has high taste and nutritional qualities, powerful pharyngeal teeth for grinding shellfish. Puberty occurs at 6-8 years with a body weight of up to 18 kg. Reproductive biology is similar to that of herbivorous fish. In pond farms, the offspring of black carp are obtained in a factory manner, just like that of grass carp; The fertility of females is 116-173 thousand eggs. The diameter of the ovulated egg does not exceed 1.24-1.44 mm, the color of the egg is golden-orange. 6 hours after contact with water, the egg swells to a size of 4.44-5.21 mm. The length of hatched larvae is 5.7-5.8 mm. They are distinguished by a black spot at the bottom of the eye.

What does black carp eat?

At an early age, juvenile black carp consume zooplankton, then chironomid larvae. This is one of the large Amur fish that feeds on benthos. From the 2nd year of life, the diet is dominated by mollusks, the number and biomass of which determine the growth rate of black carp in a given reservoir. Black carp is a heat-loving fish - active feeding and a high growth rate occur when the water temperature is above 20 ° C, and at 16 ° C it feeds less. At favorable temperatures, fish aged 4 years can eat 1.4-1.8 kg of zebra mussel per day. Black carp is capable of consuming not only single mollusks, but also dreusena. In addition to dracena, it can eat toothless.

Black carp can also consume other benthic organisms, as well as feed. But in this case, the growth of black carp slows down, and the fat content in the fish’s body increases.

Stocking density of black carp when grown in a pond

When growing black carp in fish ponds in the south of Ukraine at a planting density of larvae of 50 thousand pcs/ha, the average weight of fingerlings was 15 g. The yield of yearlings from wintering was 60-70%.
In feeding ponds in a polyculture with carp and herbivorous fish, it is recommended to grow both two-year-old black carp and fish of older age groups of black carp at a stocking density of 15 pcs/ha. The fish productivity of ponds for black carp fingerlings is 250-400 kg/ha.

 

  

 

Benefits of rearing black carp in aquaculture

What are the benefits of growing black carp in a pond? Let's look at just a few of the most important aspects:

• Black carp meat has excellent organoleptic properties, which ensures its sale on the market.
• Black carp is very promising for stocking water bodies rich in mollusks.
• Black carp is interesting not only in terms of its use to combat invasive diseases, but also its introduction into natural reservoirs and reservoirs, in which large areas of spawning grounds have become unsuitable for fish spawning due to the colonization of mollusks.
• It is beneficial to stock black carp fish in cooling ponds and irrigation systems, where it will eat mollusks that populate the underwater part of hydraulic structures and require periodic cleaning of fouling.
• Black carp fish is an interesting object of sport fishing.
• Black carp acts as a biological ameliorator of fish ponds. By eating mollusks, it reduces the risk of many invasive diseases, the intermediate hosts of which are mollusks. To combat trematodes (diplostomosis and post-diplostomosis) of pond fish in the Krasnodar
• Territory, it is recommended to stock water bodies with black carp, with a stocking density as in the table below.
• Black carp are grown in polyculture with herbivorous fish and carp, as well as in other polyculture options, without competing for food in doem.
• Black carp fish can be used for bioindication of ponds for epizootic conditions; for this purpose, the Chic reaction in black carp leukocytes is studied. In the case of an increase in the population of mollusks, a positive pool of the Schick reaction occurs in black carp, as a result of which a precipitate in the form of polysaccharide granulation is abundant in the cytoplasm.
• Black carp has good winter hardiness, which is not inferior to carp.

But there are also disadvantages when growing black carp, the main ones are the following:

• Black carp are not grown in monoculture; this is practically impossible, without additional feeding, which is extremely undesirable.
• Sexual maturity of black carp occurs quite late.
• For a large fish farming enterprise, it is necessary to maintain its own broodstock and breed black carp in a factory way. However, part of the obtained fish seeding material can be sold to smaller farms, which will be profitable, since there are almost no own broodstocks.
• When growing black carp in a polyculture with carp, it can switch to feeding on mixed feed, which will lead to a slowdown in its growth and fat will begin to be deposited in muscle tissue.

 

Table - Standards for stocking reservoirs with black carp, pcs/ha for disease control

 

Average weight of black carp, g	Reservoirs
	drainage ponds	semi-discharge and channel ponds	estuaries and reservoirs
10-15	30-50	70-100	100-150
250-750	15-25	20-40	45-50
750-1500	10-20	15-30	35-40
1500-2500	10-15	15-20	25-30

Breeding black carp in fish farming

 

Black carp breeders are raised in fish ponds and complex reservoirs, where the water temperature in summer exceeds 22°C and where there are a lot of mollusks. The planting density of yearlings is 30-50 pcs/ha.
In repair ponds, black carp breeders are kept in a polyculture with herbivorous fish and carp at a stocking density of 15 pcs/ha.

What to feed black carp? It is not recommended to feed black carp breeders with compound feed. If there are no shellfish in the pond, they are delivered from other reservoirs. Wintering is carried out in ordinary carp ponds.
Good results are obtained when raising breeding herds of black carp in shellfish-rich cooling ponds of energy facilities, where maturation occurs at the age of 7-8 years, while in ponds - only at 10-13 years. Breeders are caught from cooling ponds in late autumn or early spring, after which they are kept in ponds.

How to carry out factory reproduction of black carp

Hatchery reproduction begins at the end of the incubation period of herbivorous fish, in warm waters - in mid-late June, in ponds - in late June - mid-July.
In males, upon the onset of puberty, the pectoral fins become rough, which the fish farmer can use as a signal for pituitary injections using the same technology as for herbivorous fish. Other technological processes are also not significantly different. Since the body of black carp breeders is covered with a large amount of mucus, great care should be taken when handling them.

Incubation of eggs and maintenance of black carp larvae

Incubation of eggs and aging of black carp larvae are carried out in VNIIPRKH, IVL-2, “Dnepr”, “Amur” devices (the norms for loading eggs are the same as for herbivorous fish).
The optimal water temperature for incubating eggs is 22-26°C, a decrease to 20°C and an increase to 28°C is acceptable.

Raising black carp larvae

3-5-day-old larvae that have switched to active feeding are raised in fry ponds in a monoculture at a stocking density of 1 million pcs/ha for 3-4 weeks to a weight of 300-500 mg, while the yield of fry is 50-60%. The fry are fed with starter feed or small fractions of compound feed at the rate of 2 kg per 100 thousand specimens. per day. The fry are caught at cooler times of the day and counted using a volumetric method (using a colander).

Black carp larvae can be reared in a RAS, and the yield increases from 60% to 95%. In RAS, larvae are kept at a stocking density of 1000 thousand pcs/ha in RAS tanks with a volume of 300 liters. Growing black carp to a live weight of 300–500 mg occurs in 3 weeks in a RAS, while in nature this process will take a month.

When rearing larvae, the requirements for abiotic environmental factors are exactly the same as for herbivorous fish.

Raising fingerlings

It is carried out in nursery ponds in polyculture with herbivorous fish (without carp). When growing black carp fingerlings in a polyculture that includes carp, the stocking density should be significantly reduced. It is possible to feed with ordinary carp feed according to the standards adopted for carp fingerlings. In the first months, feeding with crushed shellfish. During autumn fishing, black carp fingerlings are sorted, they are rolled into the catcher last, and often remain on the drained pond bed.
Fingerlings overwinter in a monoculture or together with silver carp (without grass carp and carp, in order to facilitate rotation in the spring).

 

Approximate standards for growing black carp in the southern regions of Russia and neighboring countries

Working fertility (female weight 10-12 kg), thousand eggs 140-240

Number of eggs in 1 g of unfertilized eggs, pcs. 400-600

Duration of incubation (h) at t, °C 

22-23                          28

24                               24

26-28                          20

Yield of one-day larvae from fertilized eggs, % 50-60

Yield of commercial larvae from one-day-old larvae, % 60-80

Density of larvae when reared in fry ponds, million ind./ha  1

Yield of grown fry from commercial larvae, %   50-60

Density of planting of grown fry in nursery ponds (when grown in polyculture), thousand specimens/ha  50

Average weight of fingerlings, g  10-15

Yield of fingerlings from grown fry,%  60-70

Fish productivity of black carp fingerlings, kg/ha  250-400

Yield of yearlings after wintering, %  80

Density of stocking of breeders and replacements of older black carp (when grown in polyculture) in summer brood ponds, specimens/ha