In pond fish farms, carp, tench, goldfish, crucian carp, ide, silver carp and silver carp, grass carp, vendace, ripus, peled, and pike are mainly raised and raised.

Carp.Possesses tasty meat, low boneiness. Carp is an omnivorous fish, unpretentious and undemanding to environmental conditions, grows rapidly - underyearlings in the middle lane reach 30-40 r,in the south - 100-200 g.Two-year-olds grow up to 500-700 rand more.

The carp family also includes tench, crucian carp, ide, silver carp, grass carp.

Tench.Unpretentious and undemanding to the presence of oxygen in the water, it can be found in water bodies in which fish are killed. Prefers overgrown with aquatic vegetation and silted ponds. It buries itself in silt for the winter. Tench grows slowly - underyearlings reach 5-8 g, two-year-olds - 80 g, three-year olds - about 250 g. Tench are grown in ponds together with carp as an additional fish.

Goldfish.It has, like carp, tender and tasty meat. It is unpretentious and hardy, so that its waste during wintering does not exceed 3-5%.

With the joint cultivation of goldfish and carp, the natural fish productivity of ponds increases 2 times.
Idegrown together with carp; the fish productivity of the ponds increases by 30-40%.

Variegated and white silver carp.These are freshwater fish that feed on plankton. Silver carp is bred in ponds from eggs to maturity. This fish grows well in the south, growing in the first year from 30 to 300 rand more, on the second - up to 1-1.8 kg,on the third - up to 3 kg.When grown together with carp, it increases the fish productivity of ponds in the south to 6-14 c / ha,in the middle lane - by 2 c / ha.

White amur.Herbivorous fish. Has a fast growth rate, growing in the first year in the south to 250 r,on the second - up to 1.5 kg,on the third - up to 3 kg.When grown together with carp, the natural fish productivity of ponds, depending on the amount of underwater vegetation, increases by 60-90 kg / ha.In ponds where carp are fed, productivity increases by 2 c / ha.
Cupid fry feed on plankton, chironomids, crustaceans. Adult cupids feed on higher aquatic vegetation, mainly underwater vegetation (pondweed, hornbeam, elodea, etc.). Joint cultivation of grass carp with carp increases the natural fish productivity of ponds.

In addition to carp fish, in the ponds of the northern regions and the middle lane together fromcarp with great success to increase productivity, you can raise fish from the salmon family, called whitefishes - vendace, ripus and peled.

Veggie and ripus.For growing in ponds together with carp, ripus is more suitable, the fingerlings of which grow up to 80-100 r,and in the second year - up to 200 rand more. In the second year, ripuses become sexually mature. With the joint cultivation of ripus and carp, the fish productivity of ponds increases by 60-100 kg / ha.Ripus-whitefish hybrids grow even better, which can also be grown in ponds.

Peled (cheese)- fast-growing fish, when grown together in ponds, underyearlings grow up to 120 g, two-year-olds - up to 300-400 g.
With joint cultivation of peled with carp, the natural fish productivity of feeding ponds increases by 150-200 kg / ha.

The value of ripus and peled for feeding ponds also lies in the fact that incubated eggs at the stage of a mobile embryo can be imported from fish hatcheries. The imported eggs are placed in ponds, in floating machines made of nylon sieve, where the eggs are pre-incubated until the larvae hatch, which are released into the ponds.

Pike.To eliminate weedy fish - competitors of carp in the use of natural food - fingerlings of pike are planted in carp feeding ponds and grown together with carp to marketable weight (250-300 rin one summer).

Until the age of one month, pike fry feed on small plankton, crustaceans and bloodworms; from the second month of life, they begin to eat fry of weed fish. Pike underyearlings also feed on larvae, adult water beetles, bugs, dragonflies, tadpoles, frogs and trash fish without harming adult carps. As a result, the natural fish productivity of carp and pike increases by 50-60 kg / ha.

Catfish

(Silurus glanis L.) deserves special attention. It grows rapidly in ponds and is disease resistant. It is a biological meliorator, eating weed and sick fish, tadpoles, frogs and other aquatic animals.

Catfish reaches sexual maturity at 3-4 years of age. Spawning takes place in coastal thickets, in deeper places. Females lay eggs on the roots of reeds, reeds and other plants. They can also be deposited in artificial nests. In ponds for spawning of catfish, hut nests are made, installing them in deepened (2-3 m) and shaded areas of the pond.

Spawning occurs at dawn when the water temperature is 18-26 ° C. Fertilized eggs become sticky and covered with mucus secreted by the eggs. The fertility of a catfish is in direct proportion to its size and weight.

Peled

(Coregonus peled Gmelin) is a planktophage. Many reservoirs are rich in plankton, which, as a rule, is underutilized, and moreover, they are significantly populated with low-value fish species. There are cases when the specific gravity of bream, carp, pike perch, ide and other valuable fish species in a reservoir is greatly reduced, which can lead to the loss of its commercial value by the reservoir.

All this requires both the maintenance of the abundance of valuable species and the introduction of new fish species into such reservoirs, which would use the free feeding niches of the reservoir and displace low-value species, which, in turn, would lead to an increase in the fish productivity of this reservoir.

Peled is especially valuable for acclimatization - the most valuable commercial fish, characterized by high plasticity (growth, maturation, nutrition) and having intraspecific biological heterogeneity, which makes it possible for targeted artificial breeding and the prospects for its introduction into new water bodies.

A number of researchers indicate that there are three biological groups of peled: river, lacustrine and lacustrine-river; its usual form - river name - is recommended for acclimatization in lakes and reservoirs, as well as for cultivation in full-system pond farms.

The lacustrine form is of particular value for acclimatization, since in the European part of the CIS, its larvae hatch in late April - early May and coincides with the highest biomass of zooplankton in water bodies.

The Central Experimental Station of GosNIORKh was the main base for the creation of a European population of peled and for obtaining planting material (eggs, larvae, underyearlings) for stocking water bodies. Her many years of experience in peled breeding showed that this fish can be successfully used in the organization of lake feeding farms, as well as it can be raised as a plankton-feeder together with marketable carp.

In pond farms, the cultivation of marketable carp is carried out, as a rule, with the use of a complex of intensification measures, among which the fertilization of ponds and fish feeding are of great importance. Fertilizing ponds and feeding fish contribute to the development of a large amount of zooplankton in ponds, which is underutilized by marketable carp, and, on the contrary, is the main source of food for underyearlings and two-year-olds.

Joint cultivation of marketable carp and peled allows obtaining much more fish from the same pond area, increasing the fish productivity of the reservoir by 100-150 kg / ha.

The absolute fecundity of peled ranges from 2746 to 137275 eggs.

High ecological plasticity allows the use of peled in feeding farms and in reservoirs of various types: mesotrophic and eutrophic.

Reservoirs with natural ichthyofauna - perch-roach - occupy a huge water area. The basis of the catch is made up of low-value and slow-growing fish species. The introduction of peled will make it possible to use the same fodder resources more efficiently and increase the fishery value of water bodies.

For the cultivation of peled, reservoirs with an area of \u200b\u200bseveral tens of hectares to several hundred thousand hectares can be successfully used. It is advisable to create peleazh farms on large reservoirs and lakes with depths from 4-10 to 30-40 meters or more, with a favorable oxygen regime.

It is also advisable to take into account the fact that the organization of a peled farm is economically profitable where there is a production fish farm for artificial reproduction of spring-spawning fish, which will allow using the hatchery all year round due to the autumn-winter spawning of peled.

The first work on the fish farming of peled, carried out in the 50s and 60s in different zones of the country, showed that this fish is highly promising for lake and pond fish farming in the taiga and forest-steppe zones. The ecological plasticity of peled made it possible to organize its cultivation in lakes of various biological and fishery types: mesotrophic, eutrophic and oligotrophic, characterized by the background composition of the fish population as roach-perch, roach-bream, perch-roach, whitefish and crucian carp.

Depending on the natural features of water bodies and the leading environmental factors affecting the survival and growth rate of peled, by now the following methods and forms of its commercial cultivation have developed.
1. Cultivation of commercial underyearlings weighing 80 - 150 g in crucian and fishless eutrophic lakes. Depending on the level of biomass and zooplankton production, the stocking density of larvae ranges from 1.5 to 3 - 4 thousand pcs / ha.
2. Cultivation of commercial two-year-olds weighing 250 - 400 g in crucian carp and in reservoirs of other types. In the first case, crucian carp lakes can be stocked with larvae, if it is possible to use aeration means, or yearlings grown in special nurseries. In the second case, non-clogged lakes of different types of fishery are stocked with large underyearlings weighing 25 - 40 g.
3. Growing peled of different ages in feeding ponds together with carp.
4. Cultivation of peled of different ages in reservoirs from the planting of young of the year.
The best results are obtained when growing marketable peled in small lakes with an area of \u200b\u200bup to 1000 hectares and feeding ponds with an area of \u200b\u200b80 - 100 hectares.
Depending on the adopted form of lake fish farming - extensive or intensive, that is, on the volume of material costs and work on the fundamental and current reclamation of water bodies and their zonal position, the average peled catches represent the following values.
In the Kazan fish farm of the Tyumen region, stable and high catches of peled - 70-260 kg / ha each - are obtained on small lakes over the past 12-15 years.
For the category of medium-sized lakes, the normative, ie, common, are peled catches of 20 - 30 kg / ha. On the lake Duvankul of the Chelyabinsk region with an area of \u200b\u200b4 thousand hectares in 1970 - 1980 annually grown at 50 - 74 kg / ha of large peled.
For large lakes and reservoirs, catches of 3 - 8 kg / ha will be common.
Depending on the natural zone, the feeding capacity of water bodies and the timing of the cultivation of marketable peled, the increase in its mass for one or two growing seasons differs significantly. This circumstance should also be taken into account in the practical work of fish hatcheries. Figure: 65 clearly illustrates the general dependence of the amount of fish production on the duration of the growing season and the net production of zooplankton organisms that are food for peled.
In the 1980s, the catches of peled grown in the USSR outside the range amounted to 3.8 - 4.3 thousand tons per year, of which 1.3 - 1.4 thousand tons were grown in the Tyumen region and 1.0 - 1, 3 thousand tons in the Chelyabinsk region. In the European part of the country, catches reached 0.8 - 1.0 thousand tons. The quality of marketable products gradually improved: if previously commercial underyearlings with an individual weight of 80 - 150 g accounted for 65 - 70% of the catch, and the rest was fish of 2 - 3 years of age weighing 300 - 700 g, by the end of the 1980s, due to an increase in the number of nurseries and aeration equipment, their ratio changed: now they began to grow large peled 2.5 times more than marketable fingerlings. It is important to note that 90 - 96% of marketable peled is grown in lakes, the rest - in ponds and reservoirs.

Peled (cheese) Coregonus peled (Gmelin) is a valuable commercial fish that lives in the water bodies of the Far North and Siberia (Fig. 45). Before resettlement in the water bodies of north-west Russia, the western boundary of its distribution was the Mezen River, which flows into the White Sea. Peled reaches the greatest number in the Ob basin, where 95% of the total amount of this fish caught in the CIS countries is caught.

This is a large fish - up to 40-55 cm long, weighing 2.5-3 kg. Branchial stamens 49-68, upper jaw slightly longer than lower. There is a dwarf form of peled. It spawns in autumn in lakes, in the place where the springs exit, and in rivers on pebble or sandy ground. Fertility is within 5-85 thousand eggs. In places of natural habitat, it reaches sexual maturity at the 3-5th year of life. It feeds mainly on planktonic crustaceans.
There are lacustrine and semi-anadromous populations. Peled is less demanding on the content of oxygen dissolved in water compared to other whitefishes. It can live in eutrophic lakes with an abundance of algae and zooplankton. Respiratory depression occurs when the content of dissolved oxygen decreases to 2-3 mg / l.

Peled feeds on plankton, but in the northern lakes it also eats benthic organisms, and peled does not stop feeding in winter.
Peled becomes sexually mature in different water bodies at different ages: in Siberia - from 3+ to 6+, acclimatized in water bodies of other parts of the country, fast-growing peled ripens at the age of 1+ and 2+. The absolute fecundity ranges from 3 to 175 thousand eggs, on average 20-50 thousand. The spawning period in different reservoirs from September-October to December is also different: spawning begins at water temperatures below 8 ° C and more often occurs at lower temperatures.
Peled as an object of aquaculture has significant advantages over other planktophages, for example, the silver carp, etc.
1) can eat at both low and relatively high water temperatures (up to 25 ° C);
2) grows well in both completely fresh and highly mineralized water (up to 20 g / l);
3) incubation of embryos takes place in winter, when the incubation shop is free and there is a labor force;
4) water heating is not needed for artificial reproduction of peled;
5) peled meat is distinguished by high taste, which determines the high demand and relatively high price;
6) peled lends itself well to technological processing, which allows you to load smoking shops in the off-season and increase the profitability of fish production;
7) growing peled together with carp and herbivorous fish contributes to the prevention of helminthoses, the intermediate hosts of which are copepods actively eaten by peled;
8) for growing peled in mono- and polyculture with other fish, no compound feed is needed;
9) the peled is early ripening, its females mature in the 2nd or 3rd year of life;
10) the catch of peled is carried out quite easily both with active fishing gear and with the inflow of fresh water, as well as with the help of fish catchers behind the drainage of the ponds;
11) in monoculture, fish productivity of ponds for peled can reach 5-6 c / ha, in polyculture - 2-3 c / ha;
12) peled, like other whitefishes, easily adapts to adverse conditions.
The regular introduction of peled into lakes can cause a decrease in the number of indigenous low-value non-commercial fish, an increase in the yield of fish products.
The acclimatization of the Pechora peled in the reservoirs of the Arkhangelsk region led to an acceleration of its maturation by one to two years compared to the peled from the parent reservoir. Peled used crustaceans as food, which were not consumed by native commercial fish - whitefish, bream and ruff. For stocking, you should use the lake form and stock those reservoirs where there are no planktophages.
Embryonic development of peled in natural conditions at a water temperature b, 2-2 ° C at the beginning of development and 6-8 ° C at the end lasts 160-200 days, in fish hatcheries - at a temperature of 0.4-4.9 ° C - 159-171 days. The size of the hatched larvae is 8.5-10.8 mm. The most favorable temperature range is 2-5 ° C. Sublethal water temperature for embryos is -10-1 ° C, lethal -14-20 ° C.
The most sensitive to the effect of water temperature are the stages of fertilization, the beginning of embryo formation, the formation of a tail bud, the beginning of eye pigmentation, hatching, and the transition of larvae to mixed feeding.
Plant rearing of peled larvae, like other whitefishes, can be carried out at a water temperature not lower than 5-6 ° С and not higher than 16-18 ° С. The rate of feeding with live zooplankton increases from 30-40% in early larvae to 50-60% and 100% of body weight in later larvae.
When reared on artificial feed, in 30 days, peled larvae reach a mass of 30 mg with a survival rate of 80-95%. Peled underyearlings in the basins reached a weight of 7-9 g (Table 95).

Table 95. Standards for rearing peled juveniles in pools on artificial feed

Index	Larvae	Fry	Underyearlings
Water layer depth, m
Water consumption, l / s / m 3		0,3-0,5
t water, 0 С	8-16	15-17	16-19
Average weight of fry, g
initial	0,003	0,03
the ultimate	0,03
Granulated feed (brand)	Starting AC-8		4-84
Grits size, mm	0,25-0,5	0,5-1
Feeding frequency, once a day
Feed consumption, kg / g
Stocking density, thousand pcs / m 3
Survival,%
Cultivation period, months

The autumn harvesting of ponds in which peled is grown together with carp is carried out in accordance with local conditions, as a rule, at a water temperature of 5-6 ° C. In relatively small ponds, with an area of \u200b\u200bup to 3-5 hectares, it is advisable to start fishing even before the complete discharge water and final harvest; part of the juveniles can be caught at a water temperature of 10-15 ° C with a hamsoros seine with a mesh of 3.6-6 mm, depending on the size of peled underyearlings. The fry are transferred from the seine to the transport container in buckets, basins, etc.
This method is advisable when it is necessary to transport peled over a long distance, since it practically excludes injuries and siltation of the gills. For this period, until the full harvesting of ponds has begun, and carp feeding has already been stopped due to low temperatures, it is necessary to plan the transportation of planting material and pedigree peled from farm to farm, since there is enough labor and this operation can be carried out without haste, and also ensure good preservation and accurate accounting. This operation (catching and transportation) can be performed during the entire period of peled growing even at a relatively high water temperature (20-22 ° C), selecting only the mesh size of the seine in order to avoid embracing the fry, avoiding all manipulations in hot weather.
Sources of obtaining fertilized eggs. For the formation of broodstock and the rearing of underyearlings as fish seed, fertilized peled eggs can be obtained from natural reservoirs and reservoirs where broodstock already exist (Lake Son-Kul in Kyrgyzstan, Endyr in Siberia, etc.), and incubation shops in Leningrad, Novgorod , Pskov and other areas. It is advisable to create your own broodstock and hatcheries in the field.
Transportation of fertilized peled eggs. Peled caviar, like other fish species, is transported at one of the stages of development that are weakly sensitive to mechanical influences (Table 96, Fig. 46) in isothermal boxes measuring 65x50x50 m on frames. The box is completed with 18 frames, the loading rate for one frame is 150 thousand pieces. The total working capacity of the isothermal box is 2.5 million eggs.
The optimum temperature inside the box during transportation is GS, the maximum duration of transportation is 7-8 days, the permissible deviation during transportation is up to 15%.

Table 96. Periods of reduced sensitivity of developing peled eggs to external factors

Development stage	Stage of development	Age, days
	Morula (Fig. 46, a)
	Blastula (Fig. 46, b)	9-9,5
	Closure of the yolk plug (Fig. 46, c)	27-45
	Intense pigmentation of the eyes (Fig. 46, d)	70-75
	Movable pectoral fins	110-115
	Development on the branchial arches of the primordia of gill petals (Fig. 46, e)	180-200

During transportation, it is necessary to shower the caviar (sprinkling with water). For the first time, this procedure is carried out 24 hours after loading the caviar into the box, then after every 12 hours of travel. The temperature of the water used for the shower should not differ from the temperature in the isothermal box by more than ° C.
Incubation and pre-incubation of peled eggs. For these operations, Weiss devices (with a capacity of 8 liters) are used, containing from 300 to 800 thousand eggs. The devices are placed in racks in 1-2 tiers. The common water supply pipe should be located at the level of the upper edge of the flasks; this prevents developing eggs from entering the water supply system in case of emergency water supply interruption.
Incubation is carried out at a temperature of 1-4 ° C. The water entering the workshop should be free of mechanical impurities and representatives of predatory zooplankton, which are often found during incubation in the southern zones of pond fish farming. Installation of reliable filters on the water supply system is desirable. Water saturation with oxygen should be at least 60%, pH - 7.5-6.5. Water consumption for one Weiss apparatus is set depending on the amount and stage of development of eggs and the oxygen content in the water; the average consumption rate for one device is 2.5 l / min.
During the entire incubation period, the selection and accounting of dead eggs are carried out, the flow rate in the apparatus is adjusted, the daily measurement of the water temperature, oxygen content. The results of observations and analyzes must be recorded in a diary for further various fish-breeding calculations concerning the timing of hatching, percentage of survival, etc.
The development of peled embryos lasts an average of 164 degree-days, which is about 100 days within the I-II fish farming zones,
In more southern zones, development ends earlier: in zone III - 120 days, beginning at 0.4 ° С, completion - 4, hatching - 8 ° С; in IV - 110-115 days, beginning at 0.2 ° С, completion - 4, hatching - 12 ° С; in zone VI -100-105 days, beginning at 2 ° C, completion - 4, hatching - 14 ° C. The timing of development can vary significantly depending on the conditions of incubation.

Peled caviar development

Stage of development	Sum of daily average temperatures (degree days)
First division
Second division
Fourth division
Morula (large cell)
Morula (small cell)	11,1
1/2 gastrulation and fouling of the yolk sac	14,4
Formation of primordia of axial organs	17,8
Blastopore closure
The beginning of the growth of the tail bud	23,8
Onset of eye pigmentation and formation of pectoral fin rudiments	31,2
The beginning of the formation of the primordia of the caudal fin and pigmentation of the trunk	64,7
Dorsal fin primordia and head pigmentation	142,7
Hatching larvae	164,4

When saprolegnia appears in the apparatus, it is necessary to treat the caviar with one of the following dyes: malachite green with a dilution rate of 1/200000, processing duration - 50 minutes; violet with a concentration of 5 mg / l, processing time - 25 min.
The prepared dye solution is introduced directly into the apparatus, in which the water supply is previously stopped.
The period of hatching of peled larvae lasts from 5 to 15 days. The larvae are kept in cages of nylon gas ╧ 17, installed in trays manufactured by the Yeisk shipyard, no more than 6 days. Water consumption in trays - 5-6 l / min.
The larvae are transported in plastic bags with a capacity of 40 liters. When transported for up to 5 hours, a stocking density of 100 thousand larvae in 1 package is recommended, more than 5 hours - 50 thousand larvae in 1 package. Permissible deviation during transportation is 157о. Milk cans can be used for short-term on-farm transportation. The density of landing in them is determined by the duration of transportation.
Basic requirements for growing conditions of peled underyearlings together with carp underyearlings. Cultivation of peled underyearlings can be carried out in carp rearing fish ponds, the recommended area of \u200b\u200bwhich is up to 20 hectares. The average depth of ponds should be: for zone III - not less than 1.2 m; IV - not less than 1.6 m; VI - not less than 2 m.
When choosing ponds for growing peled, it is necessary to pay attention to the possibility of water supply in summer at night when the water temperature rises and the oxygen content decreases.

Main hydrochemical indicators for ponds

Transparency	light turbidity is acceptable
Oxygen, mg O 2 / l
Oxidability, mg O 2 / l	15-20
Carbon dioxide, mg СО 2 / l	10-15
Hydrogen sulfide, mg H2S / l	not allowed
Alkalinity, mg eq / l	from 1.5
Hardness, German degree	5 and higher
Nitrates, mg NO 2, / l	up to 1.5
Phosphates, mg P2O5; / l	up to 0.2
Sulfates, mg / l	5-300
Total iron, mg / l	up to 1
PH
t, ° C	0,2-18(22)

Growing underyearlings. Ponds are stocked with peled larvae in late March - early May, depending on the timing of the completion of incubation.
The stocking density of peled larvae in nursery ponds is determined in accordance with the state of the natural food base, the expected fish size and the length of the rearing period. For growing peled juveniles weighing 15-20 g, the following densities of larvae are recommended (thousand pieces / ha):
in polyculture with carp (zone 111.1V): carp -60, peled-15-20; (IV zone): carp - 65, peled - 20-25;
in polyculture with carp and silver carp (zone IV): carp-5, silver carp - 20, peled - 20;
in monoculture (zone VI): peled - 40-60.
When growing in ponds, peled in monoculture should be planted with two- and three-year-old grass carp (biculture) in an amount of up to 200 pcs / ha.
During the growing season, it is necessary to maintain a zooplankton biomass of at least 1-2 g / m3. Stimulation of the development of the food base is carried out by methods generally accepted in fish farming, taking into account the hydrochemical situation of the reservoir. Immediately before stocking the ponds, it is necessary to make sure that small forms of zooplankton are available as a starting food for young fish.
In the first 20-25 days of rearing, due to the small amount of feed consumed by underyearlings and the absence of juvenile carp in the ponds, the stocking density of peled larvae may be two- and three-fold higher for subsequent transplantation of a part of the fry for cultivation in other water bodies.

When rearing juveniles of peled and carp together in order to reduce food competition at the first stages of development, it is advisable to increase the difference in the timing of planting peled and carp, rearing carp larvae in spawning or fry ponds; introduce starter feed for juvenile carp. The mass of the peled when planting juvenile carp should be at least 0.7 g, when planting silver carp - at least 2.5 g. The water temperature during the introduction of peled larvae should be 8-14 ° C, with the introduction of carp - 18-20, silver carp - 22-24 ° C.
During the summer period, the growth and development of underyearlings is monitored in accordance with the indicators given in Table 97.

Table 97. Pond rearing of peled underyearlings

Index	Indicator value	Optimal value
Flow rate, once a season
Overgrowth,%		until 3
t water surface in summer, ° C	14-22(26)	12-19(10-22)
	4,5-8,0	8-11 (up to 6)
	10-15	5-10 (up to 30)
Permanganate oxidizability, mg 0, / l	7-15	7-7,5 (6-8)
Mineralization, t / l	0,1-1,0	0.1-0.6 (up to 6)
	up to 1.5	0.6-1.2 (traces)
	up to 0.2	0,2-0,3
Total iron, mg / l	up to 1
Alkalinity, mg.eq / l	up to 1.5
Zooplankton biomass, g / m 3	1,3-3,7	5-10 (up to 20)
Biomass of zoobenthos, g / m 2	3,4-6,2	5-15

Indicators of the frequency of sampling of control samples when growing peled fingerlings

t water	daily
Gas regime of ponds	1 time in 2 days
General hydrochemical regime of ponds	2 times a month
Hydrobiological analyzes of ponds	every ten days
	every ten days
Measuring the mass and length of fish

Particular attention should be paid to the hydrochemical state of water bodies in the hottest season, during the period when the threat of freezing phenomena arises.
Catch, transfer of fry. The catch of peled fry with the aim of rarefying the planting is carried out with a non-sticky nonsense 15-20 m long. The fish are accumulated in floating cages at a water temperature not higher than 20 ° C. The catch of peled fry when reared together with carp underyearlings is carried out after 1-1.5 months. after planting the peled. The selection of the mesh size is carried out according to the results of the control catch. The net should not encircle peled underyearlings, and fry of carp should freely pass through it.
Control fishing in nursery ponds is carried out every ten days. In the first three decades, gauze drags are used as fishing gear, further nonsense from knotless delhi (khamsoros). The selection of the required number of fish from fishing gear is carried out in the water. To obtain representative results of fish culture analyzes, it is sufficient to examine 25 fish.
Autumn fishing of ponds. Produced at a water temperature not exceeding 14 ° C. The fish catcher (Fig. 47) is equipped with a fish receiving structure that prevents injury to peled underyearlings. It is made from a knotless delhi, it has the shape of a cradle (Fig. 48). When lowering the ponds, it is not allowed to stir up the silt, which clogs the gills, which causes the death of the peled.
Wintering of peled underyearlings. It can be carried out in wintering carp ponds at a stocking density of 100-120 thousand pcs / ha, however, in the III and more southern zones, the best option is to winter peled in specialized winter ponds, similar in their hydraulic parameters to carp nursery ponds (area 10-20 ha) in the presence of winter zooplankton biomass not less than 0.8 g / m3. The stocking density of peled in winter ponds, subject to active nutrition, corresponds to the standards for planting in summer ponds. The growth of peled underyearlings during the winter period up to 20-30% is possible.
Control in the winter is carried out according to the same indicators as in the summer. Particular attention should be paid to the hydrochemical situation during periods of possible occurrence of freezing phenomena, for example, when water appears on the ice surface, heavy snowfall, etc. Fish breeding observations of the state of peled in winter ponds can be carried out by means of control fishing with the help of line nets "screens" installed in the area of \u200b\u200bwater supply. To exclude the possibility of selective selection, several "screens" with different mesh sizes are used simultaneously.
With a decrease in the content of oxygen dissolved in water to 2.5 mg / l, it is necessary to maximize the flow rate and, if possible, enhance aeration.
Growing two-year-olds. The condition and quantity of fish after wintering is determined by a control catch covering a certain area.
At 70% yield (of the number of juveniles during planting), fish productivity will reach the standard level for this zone, namely: carp - 11.2; peled - 4.2 c / ha. In this case, the biomass of residual zooplankton should be at least 1 g / m3.
Fish breeding observations of the state of two-year-old peled in winter ponds are carried out according to the same method as for fingerlings (Table 98).

Table 98. Bio-standards for pond cultivation of peled

Peled is a shy fish, but experienced fishermen know how to choose the moment and method of fishing in order to grab a large specimen, which will be prepared in any way in the future. It is permissible to grow cheese in a pond for personal consumption or for sale. Such a business is considered profitable if you acquire regular customers.

Who is the peled fish?

Peled is a lake and river fish, which is popularly grown not only naturally, but also artificially. On average, the length of the fish reaches about 40-55 centimeters with a weight of 2-3 kilograms, sometimes the body weight can be 4-5 kilograms. The lifespan of the cheese is 8-11 years.

The peled has a laterally compressed body, of a silvery color. A clear distinguishing feature is a well-visible dark gray stripe on the body. Black dots are located on the head and dorsal fin. It has a terminal mouth, multiple branchial stamens and a longer upper jaw. Peled is characterized by the presence of an adipose fin located between the dorsal and caudal. The body of the fish is densely covered with scales.

There are three forms of peled:

• Fast-growing river... Occurs in rivers and lakes. Ripens by the third year of life.
• Lacustrine dwarf... The fish got small size due to living in small lakes.
• Ozernaya ordinary... It does not leave its habitat, all the time it is where it settled.

Peled's competitors include juveniles of other whitefish, vendace and tugun. The natural enemies of the fish are pike, burbot and other species of fish that devour eggs.

Where does it live and what conditions are required?

Peled is found in fresh water bodies of Eurasia, in rivers and lakes stretching from Karelia to Kolyma. Fish do not go out to sea, into salt water. Peled spawn in lakes. Does not prefer fast flowing waters. It also lives in lakes most of its time. Due to these features, peleds are being bred over a large area, mainly in the northwestern part of Russia.

But some varieties of cheese live in the running water of northern rivers. Peled prefer to keep in flocks, avoiding dense underwater vegetation. If at a young age the individual is strong, it usually leaves the flock in the summer, settles at a depth. Very young specimens have a different habitat: they settle in coastal waters and swim in places populated with vegetation. After the ice melts, in the spring, river fish seeks to get into the floodplain lakes, where it will be able to recover, gain strength and get enough of it.

In addition, she tries to find herself in tributaries or oxbows, where a lot of food for peled accumulates by the spring. As soon as the flood subsides, the peled tries to leave such reservoirs and return to the rivers.

What does a peled eat?

The main diet of cheese is zooplankton and crustaceans. This greatly complicates the catch of peled: it rarely pounces on the bait, which is familiar to other representatives of the fish fauna. Peled is caught at any time of the year. In order to find the place where the fish feeds, pay attention to specific circles and splashes on the surface of the water surface.

Peled can also use maggots, worms, mosquitoes, bloodworms, mollusks, amphipods, gammarids as food. For this reason, in the summer, fishermen use the non-muzzle method for fishing.

The spawning process of peled occurs in the autumn season, when freeze-up begins or ends, in September-December. As spawning grounds for fish, they choose places covered with pebbles, and providing for a spring. For normal reproduction, fish need cold water, its temperature should not be more than 8 degrees. More often spawning occurs at temperatures closer to 0 degrees.

Peled is capable of sweeping more than a couple of tens of thousands of eggs, with diameters of about 1.5 millimeters.

The hatched larvae gradually grow, and are no longer considered fry, reaching 6-7 months of age. In rivers, the maturation of fish is a little slower, it matures by 3-8 years. But lake representatives mature much earlier - by 2-3 years. It all depends on the nutrition of the fish, the better it is, the faster the peled will multiply, and spawning will take place every year or with a break of 12 months.

Is the fish opisthorchiasis?

It is not common for everyone to think about the danger that fish lovers may face after a river catch. Almost 90% of fish are infected with opisthorchiasis worms. Fish with helminth larvae are caught in rivers such as the Volga, Ural, Ob, Irtysh, Dnieper, Northern Dvina.

It is widely believed that only fish of the carp family are carriers of diseases. Previously, it was believed that peled has nothing to do with worms. But it is not so.

Carp fish are considered to be the leaders in the field of infestation, but at the same time, other species of fish that prefer cold water can become infected. Opisthorchiasis can take root in the body of many fish, in this case, peled is no exception. Over the past few years, the causative agents of opisthorchiasis have been repeatedly found in this whitefish species. For this reason, it is especially dangerous to eat fish, because there is a risk of infection with worms.

The presence of worms in peled depends on where the peled lives. Earlier, opisthorchiasis settled in mollusks and fish of the carp family. Cheese can be contaminated if it is in the same water with carp fish.

Peled is a predatory fish that eats shellfish and other fish, which is why it becomes a source of infection for others. The eggs of the worms penetrate into the body of the cheese together with the eaten specimens, ripening and further development take place there.

Fishing features

Catching peled can be challenging. In the absence of plankton, the fish will feed on bottom organisms, which is why they will not pounce on standard baits. The fish does not like sharp cutting, because this leads to the fact that its weak lips are torn. Sharp playing ends with the fish going into the depths.

Catch time

Fish are caught all year round, but more often in summer. The fish has an excellent feature - it calmly tolerates the lack of oxygen in the water, which allows it to feel better throughout the winter. In the period just before the end of winter, reservoirs are poor in food and any feeding will be attractive for peled. In such a situation, she will swim out to the very ice, making it easy prey for a fisherman.

Tackle

Peled is a shy fish, and it is better to catch it in complete silence. It is permissible to go fishing at any time of the year. A splash in the water and special circles will help to find a habitat. For winter fishing, it is recommended to use a regular fishing rod, and in summer, a float rod without a sinker is considered effective. It is no less popular to catch cheese on fly fishing with a 5-meter rod, gill nets and seines.

For fishing peled, it is better to use a line with a thickness of 0.2-0.22 mm. You must choose the hook number 4 or 5. The fish bite resembles a sharp jerk. If a large individual comes across, there will be difficulties with playing.

To catch peled on the Volga, it is advisable to have a pobradok with you - a simple meter long rod. A fishing line is tied to it, 2.5-4 meters long. In the process of fishing, they use several baits. The beginning of fishing begins with the fact that the fisherman goes to the depth and tries to make the water cloudy, because the peled is especially attractive to the mud. She aspires to a cloudy cloud, counting on good prey. She will notice the bait and grab it. Hooking is required very carefully, but at the same time sharply, although this may result in the loss of the catch.

Large peled are capable of leading the line for a long time, until the fisherman makes every effort to pull the fish out. Experienced fishermen put the tackle on the bottom, at the feet, holding on to the top. The current will gradually carry the bait down, which is why it sometimes needs to be pulled back. After 10-15 minutes of such fishing, they climb a couple of steps upstream, the technique is repeated.

Bait

In the summer, fishermen use an ordinary earthworm, mollusk or bloodworm as bait. It is permissible to try to catch peled with maggots, but this bait, unlike the previous options, is less effective. The hook is held approximately in the middle of the water column. The favorite depth of the peled is the distance from the bottom of about 70-150 centimeters.

Live bait is not used in winter. In such a situation, it is best to use a jig.

There is one more way to increase the chances of catching peled: use a special, shaded hole. This is done quite simply. Rolls are made of snow around the hole so that the shadow from them completely shades the water of the hole. The height of such a roller should be about 1 meter. The bait is kept no deeper than 5-6 centimeters from the bottom edge of the ice. If the fish does not bite, it is recommended to catch it both at medium depths and near the ice itself.

Is fish farming and raising possible?

Breeding and growing fish takes place in stages:

1. First stageconsists of a previously prepared broodstock from which eggs are obtained. For this, the best females and males are selected, they are launched into small ponds, from where they are subsequently caught. In November, fish are seated in separate flowing ponds indoors for maturation. The volume of ponds should be at least 70 cubic meters and have an elongated shape. In order for the fish to be comfortable in them, the water is renewed regularly - every 8 hours. It is permissible to let no more than 1,500 breeding individuals into one pond.
2. Second phaseconsists in the fact that ready-made producers are sent in groups of 250 individuals to small pools, where the selection of eggs is carried out. Usually males are "used" several times with intervals of 2-3 days. The fertilized eggs are sent to the incubator to ensure that the embryos are optimally oxygenated. The incubation period lasts 123-145 days, depending on the temperature regime. At this time, it is imperative to carry out preventive washing of caviar using special solutions. After the larvae appear, they are sent to the cages. After a week, they are ready to eat actively.
3. Stage threebegins with the launch of the fry into the fingerling pond, where they grow together with carp. The stocking density is carried out at the rate of 20-25 thousand larvae per 1 hectare. It is optimal if the depth of the pond is no more than 3 meters, and the area is 15-20 hectares. At the same time, the amount of silt at the bottom of the reservoir does not matter, because the peled leaves it together with the drained water. Ponds with young growth do not need filtration for two months. Only when the fish reach this age is it necessary to create a flow through the reservoir.

Although the peled can feel fine in warm water, it is still better to keep it in a reservoir where the water temperature does not exceed 22 degrees. The cheese is caught when the mark drops to 5 degrees or below.

Today the survival rate of peled is about 50%, due to which about 2 quintals of fish are obtained from 1 hectare with an average weight of about 20-25 grams of underyearlings.

Peled underyearlings often overwinter in the wintering grounds of carp fish, while the oxygen content should be at least 5 mg / l. the planting rate of peled underyearlings per hectare is up to 120 thousand. In recent years, fish farmers have been building wintering complexes for peled underyearlings, which are "greenhouse" pools, which are buried 2 meters into the ground.

It is difficult to answer unequivocally regarding the period of fish catch for further implementation. In the natural environment, the mass of a three-year-old peled is 200-350 grams, a four-year-old fish is 300-600 grams, a five-year-old fish is 500-700 grams. It will be more profitable to sell fish at the age of two.

Survival and fish productivity

In the first summer of life in ponds, the survival rate of peled is 80% to the number of planted larvae, in the second year 80-90% in rivers, 60% in lakes to the number of planted underyearlings. When the peled reaches the age of three, its growth slows down, which is why it is caught from the lakes. Unlike other whitefishes, peled is undemanding to the level of oxygen in the water, due to which it tolerates water temperatures of about 0 degrees.

The fertility of the two-year-old cheese cheese grown in the pond weighing 350 grams is 15 thousand eggs, and weighing 500 grams - 200 thousand eggs per female peled.

The productivity of fish from shallow lakes when grown together with carp is about 100-120 kilograms per 1 hectare, in ponds - up to 250 kilos per 1 hectare. It is recommended to grow peled in large ponds, where the total area reaches at least 100 hectares.

The benefits and harms of fish

The consumption of peled in food has a beneficial effect on the human body. It contains many micro- and macroelements that promote cell regeneration, normalize the functioning of the nervous system. Peled meat is rich in chromium, which is essential for maintaining optimal blood sugar levels.