Journal of Environmental Treatment Techniques
2019, Volume 7, Issue 3, Pages: 474-478
etc. are added to feed, so as not to increase the cost of
fish. Inorganic fertilizers are practically not used because of
their high cost. In tropical areas, plants grow all year round,
and therefore the introduction of inorganic fertilizers is
impractical.
Planting material is mined in natural waters. In Japan and
Taiwan, juvenile carp are caught during its upstream and
river estuaries. Along with this, they use the method of
hormonal stimulation of producers - the method of pituitary
injections, which gave a rather strong impetus to the
development of pond fish farming (9,15,20).
morning) in a mechanized way. The feed coefficient ranges
from 2 to 3 (depending on soil fertility and fish size).When
°
C
the water temperature below 15 fish cease feeding. The
calculations of Israeli scientists found that with a production
efficiency of fish 2000 kg / ha, 400 kg / ha - obtained from
the natural forage base, 400 kg / ha - due to fertilizers and
1200 kg / ha due to artificial feed. In Israel, fish farming
involves the joint cultivation of heat-loving fish species of
carp, mullet and tilapia hybrids (in waters with a salinity of
2,000 to 8,000 ml Cl / l (in the Dead Sea region, where water
is unsuitable for spawning). In the north of Israel, as a rule,
these freshwater fish grown in water with low chloride
content (300-400 ml of Cl / l). In total, about 6500 tons of
carp are grown in Israel annually, which accounts for 37% of
the total fish production in the country (14,19).
3
.3 Carp breeding technology in Japan.
In Japan, carp cultivation is used in small deep ponds
with a strong influx of warm water and frequent feeding of
fish with complete feed, thereby achieving high
productivity of ponds - up to 200 kg / m . In ponds of oblong
a
2
3.5 European carp breeding experience.
°
C
area less than 1 m at a water temperature of 15-30 and a
sixfold feeding fish with a mixture of rice, fish meal, shrimp,
tomatoes, productivity achieved fish production from 3.5 to 5
In Germany, ponds in standing thermal pools; thermal
ponds with chilled water; heating equipment; chilled water
thermal gutters are used for carp growing. In the thermal
gutters, they establish cages from a grid, where fish are
harvested and commercial fish is grown with intensive
feeding of fish with complete feeds. In Germany, it is
considered expedient to grow carp fingerlings in ordinary
ponds, and in the fall they are transplanted into thermal
ponds, where they are fed up, continuing the growing season.
If in the thermal ponds during the winter, the water
temperature is maintained close to the summer (due to the
constant supply of waste water from the thermal power plants
to them), then the pilots grown in such conditions correspond
in weight to the two-year-olds grown under normal
conditions. Thus, the period from spawning to commercial
fish is reduced from 2.5 to 1.5 years, which is of great
national economic importance for growing seedlings in the
second year of life. Germany ranks second in Europe's
freshwater culture (11.5% of all European production), where
rainbow trout (24 thousand tons per year) and common carp
(13 thousand tons per year) also dominate in aquaculture
products. The main importing countries for German-made
carp are Belgium and Austria (18).
2
t / ha, in small pools with weak flowage - up to 200 kg / m .
High productivity here is achieved due to a number of
favorable factors, namely: temperature, water quality,
composition of artificial feed (5).
Growing carp in cages in Japan began in 1951, when for
2
8
5 days of intensive feeding, producers received 11.5 kg / m .
The development of cage culture was facilitated by the
presence of a large number of artificial reservoirs with
stagnant water, the poor bottom of which did not allow for
fishing operations in them, but it allowed them to breed carp
in cages. Japanese cage is a grid with a flat bottom and an
open top, stretched on a frame of bamboo poles. The cage
sticks afloat with the help of several steel cylinders and is
attached to heavy wooden bars fixed to the bottom of the
reservoir. The size of the cage is from 7 to 8 m (surface area),
the depth is up to 2 m, therefore it is located near the shore
with a depth of water layer of at least 3 m (optimal for
growing).
3
.4 Carp breeding experience in Israel.
In Israel, one of the leaders in technology development in
the fish industry, aquaculture development began with the
import of carp into the country in 1927-28(18).
With regard to European leadership in freshwater
aquaculture, the largest producer of freshwater fish in Europe
is France. Its share in the total European production is more
than 14%. In this country, the main part of fish farming
accounts for two species: common carp (5 thousand tons per
year) and rainbow trout (41 thousand tons per year).
In this country, intensive fish farming is implemented on
warm brackish waters, in the specific conditions of the soil,
water and climate of this country. In many areas of Israel
there is a shortage of water, and in the one that is available,
the salt content is very high (up to 1200 mg Cl / l). Such
water cannot be used for agriculture, but it is suitable for fish
farming. Where there is fresh water, build deep ponds, which
are maintained in working condition throughout the growing
season. When they are drained, the water is poured according
to the principle of communicating vessels with the help of
pumps into neighboring ponds, and later used again. Such an
operation has been implemented for several years. The
natural productivity of fish production in such ponds is 200-
00 kg / ha, thanks to artificial fertilizers it is adjusted to 800-
000 kg / ha or more.
In the carp farms of Israel artificial feeding of fish is
widely used. For carp, they use cheap grain, oilcake, which
greatly increases the productivity of carp. High-protein
artificial feed is widely used, which is set once a day (in the
3.6 Modern state of carp production in Russia.
he first stage of industrial development of industrial
aquaculture in Russia was the technology development for
growing commercial carp in cages installed in cooling ponds
of thermal power plants. At the beginning, the possibility of
growing carp in them in the absence of a natural forage base
caused quite serious doubts among specialists who were
engaged in industrial fish farming in the world, and therefore
the first such works were started with two-year carps (4,24).
The first stage of work was associated precisely with
working out the issues of feeding fish. Already at this stage,
during which the work was carried out in net cages without
forced flow, it was determined that carp can be grown
exclusively on artificially made feed mixtures only if the
4
1
oC
temperatures are optimal for carp growth (23-33 ) (8).
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