RU2295239C1 - Method for commercial growing of air-breathing catfishes - Google Patents

Abstract

FIELD: commercial fishery, in particular, growing of commercial product such as air-breathing catfishes.

SUBSTANCE: method involves employing variable temperature water mode in rearing apparatus having closed water supply system. Air-breathing catfishes are grown using non-static temperature mode with thermal period of 24 hours. At day time, from 8 to 16 hours, temperature is increased from 24 C to 30 C, and at time from 16 hours to 8 hours temperature is decreased from 30 C to 24 C.

EFFECT: increased yield of fish product of air-breathing catfishes.

1 dwg, 6 tbl

Description

The invention relates to fish farming and can be used in commercial fish farming for the cultivation of marketable products, such as Clari catfish, under the conditions of an astatic (variable) temperature regime in closed water supply (UZV) installations.

A known method for the experimental development of biotechnology of cultivation (stimulation of puberty, development of embryos and larvae) of claria catfish, including the study of its tolerance (attitude) to some environmental factors: pH, temperature, salinity (1). However, the influence of the temperature regime of water on the stimulation of puberty and the embryonic-larval period of the development of claria catfish was studied at constant temperatures.

There is a method of aquarium rearing of juvenile sturgeon and cyprinids in variable thermal modes (2). However, this method does not consider the cultivation of catfish: the production of marketable products and the cost of feed for the cultivation of claria catfish under conditions of astatic thermal conditions in aquaculture facilities of closed water supply.

The closest technical solution is the method of artificial breeding of juveniles in a closed water supply installation, which involves the use of a variable temperature regime of water and the production of salable fish (3). However, this method relates to the Black Sea flounder and does not consider the specific parameters of the astatic thermal mode for the cultivation of commodity Clari catfish.

The objective of the proposed method is to increase the yield of fish products of clary catfish when grown in ultrasound with variable temperature conditions.

This is achieved by the fact that when using variable temperature conditions for growing clary catfish, the highest fish growth rate and increased yield of marketable products are obtained under an astatic temperature regime with a 24-hour thermal period close to temperature fluctuations in natural conditions (during the daytime, the temperature is higher, at night - morning - lower: in the daytime from 8 to 16 hours the temperature is increased from 24 ° to 30 ° C, and from 16 to 8 hours it is lowered from 30 ° to 24 ° C).

Tables 1, 2, 3, 4, 5, 6 characterize the quality of water in the ultrasonic testing, changes in temperature, the experimental design and the results of fish breeding indicators.

Table 1 - hydrochemical and bacteriological regimen in the ultrasound system.

Table 2 - scheme of experiment 1.

Table 3 - change in temperature in pilot plants.

Table 4 - the results of the cultivation of clary catfish in a UZV (experiment 1).

Table 5 - experimental design 2.

Table 6 - the results of the cultivation of clary catfish in a UZV (experiment 2).

The method of growing is as follows.

In the experiment we used a fish-breeding facility with a closed water supply cycle with the following characteristics. The volume of fish tanks is 2.0 m ³ , the volume of a mechanical filter is 0.3 m, the type of mechanical filter is floating with a load of polyethylene granules with a diameter of 2.5 mm, the volume of the biofilter is 1 m, the type of biofilter is submersible with expanded clay loading, surface area biofilter loading - 220 m ² , loading volume - 0.7 m ³ , water exchange - 70 min, compressor capacity - 60 l / min, daily recharge - 5%. To heat the water used 4 electric heaters with built-in thermostats, connected via a time relay.

Clarium catfish with an initial weight of 25 g was used as an object of research. The period of growing Clarium catfish lasted 104 days. Fish was grown at a planting density of 200 pcs / m ³ to a market weight of 450-500 g. Fish was fed manually, repeatedly, a single portion of the feed was selected based on its total eatability by the fish. The hydrochemical regime was the same in all cases (Table 1).

The experiment was carried out in four versions (table 2). In options 1, 2, 3, astatic temperature conditions were used, the 4th was the control (Table 3, drawing). In the control variant, catfish were grown at a stable temperature of 27 ° C. In other embodiments, the temperature regime was astatic. In the first embodiment, two peaks of temperature increase were simulated for 24 hours with a thermal period of 12 hours. In the second and third variants, an alternating thermal mode was created with one peak for 24 hours: in the second variant, the peak t ° - 30 ° C occurred in the morning (8 hours), at least 24 ° C in the daytime (16 hours); in the third variant, the maximum t ° - 30 ° C was in the daytime (16 hours), the minimum t ° was 24 ° C in the morning (8 hours).

The fish grew most intensively in the third version of the experiment, where a temperature regime close to natural was simulated. Catfish reached the highest average weight of 462 g, and the highest yield of fish products was obtained - 87.4 kg / m ³ , while the lowest feed costs were noted - 0.76 kg / kg (Table 4).

In the control and other variants of the experiment, the fish had a lower mass, the yield of fish products was lower, and higher feed costs were noted (Table 4).

The second part of the experiment (experiment 2), aimed at checking the results obtained in experiment 1, was carried out on the same ultrasound in two fish tanks. Two groups of fish were taken. The first group was grown at a stable temperature of 27 ° C. In the fish tank with the second group of fish, the astatic temperature regime of water was simulated with a thermal period of 24 hours (natural temperature fluctuations - the temperature is higher in the daytime, lower at night): the temperature was increased to 30 ° C by mid-day (by 16 hours), and then decreased to 8 o'clock in the morning to 24 ° C (table 5).

The final fish mass and fish yield in experiment 2 were higher, and the feed costs were lower at an astatic temperature regime with a 24-hour thermal period compared with the results of fish cultivation at a constant temperature (Table 6).

The experiments showed that the growth of Clari catfish by weight and the efficiency of its use of feed is directly related to the astatic temperature regime at a thermal period of 24 hours, with a maximum temperature of 30 ° C at 16 h and a minimum of 24 ° C at 8 h.

Information sources

1. Mikodina E.V., Shirokova E.N. Biological foundations and biotechnology of aquaculture of African catfish (CLARIAS GARIEPINUS) // Fisheries. Information materials. Aquaculture Series. M., 1997.

2. Konstantinov A.S. The influence of temperature fluctuations on the growth, energy and physiological state of juvenile fish. // Proceedings of the Academy of Sciences, biological series No. 1. M .: 1993. - S. 55-63.

3. A.S. SU 847961 A1, 1981. “A method for the artificial breeding of the Black Sea flounder-kalkan” (applicant of the Order of the Red Banner of Labor, Institute of Biology of the Southern Seas named after A.O. Kovalevsky Academy of Sciences of the Ukrainian SSR, authors A.V. Chepurnov, Yu.E. Bityukova, N .K. Tkachenko, B.N. Belyaev), 07.23.1981

Table 1
Hydrochemical and bacteriological regimen in ultrasonic testing Indicator Units measuring Parameter in UZV Norm pH 7 7 HN ₄ ⁺ Mg / L 0.85 1,0 NO ₃ ^- Mg / L 1,2 up to 2.0 RO ₄ ^3- Mg / L 0.36 0.5 Cl ^- Mg / L 23 up to 20 Rigidity mg × equiv / l 3.0 up to 8 Ca ²⁺ Mg / L 40 up to 180 Mg ²⁺ Mg / L 12.5 up to 40 Oxidizability mgO / l 8 up to 15 SO ₄ ^2- Mg / L 90 up to 100 OMC CFU / ml 1,0 × 10 1.0 × l0 ⁴ table 2
Test Pattern 1 Indicator Experience Options one 2 3 4 (control) From 8 a.m. to 2 p.m. From 8 a.m. to 4 p.m. From 8 a.m. to 4 p.m. 27 ° C from 20 h to 2 h -30 ° to 24 °. -24 ° to 30 °. during the day Temperature -24 ° to 30 °. From 16 hours to 8 hours From 16 hours to 8 hours mode From 2 p.m. to 8 p.m. -24 ° to 30 °. -30 ° to 24 °. from 2 hours to 8 hours, -30 ° to 24 °. Pool volume, l 250 250 250 250 The initial mass of fish, g 25 25 25 25 Density, pcs / m ³ 200 200 200 200 Feeding method Manually eatable Manually eatable Manually eatable Manually eatable Compounding recipe RGM-8V RGM-8V RGM-8V RGM-8V The period of the experiment, days. 104 104 104 104

Table 3
Changes in temperature conditions in pilot plants for growing claria catfish, ° C Clock Experience Options one 2 3 four 08 24 thirty 24 Constant t ° - 27 ° 10 26 28.5 25.5 12 28 27 27 fourteen thirty 25.5 28.5 16 28 24 thirty eighteen 26 24.75 29.25 twenty 24 25.5 28.5 22 26 26.25 27.75 24 28 27 27 02 thirty 27.75 26.25 04 28 28.5 25.5 06 26 29.25 24.75 08 24 thirty 24

Table 4
The results of the cultivation of Clarium catfish in a UZV (experiment 1) Indicators Experience Options one 2 3 4 (counter) The initial mass, g 25 25 25 25 The final mass, g 379 411 462 444 Feed costs, kg / kg 0.9 0.85 0.76 0.9 The output of fish products, kg / m ³ 70.8 77,2 87.4 83.8 Table 5
Test Pattern 2 Indicators 1 (control) 2 (experience) Temperature mode 27 ° C, during the day From 8 a.m. to 4 p.m. -24 ° to 30 ° C From 16 hours to 8 hours
-30 ° to 24 ° C Pool volume, l 250 250 The initial mass of juveniles, g one hundred one hundred Density, pcs / m ³ 200 200 Feeding method Manually eatable Manually eatable Compounding recipe RGM-8V RGM-8V The period of the experiment, days days. 45 45 Table 6
The results of the cultivation of Clari catfish in a UZV (experiment 2) Indicators Experience Options one 2 The initial mass, g one hundred one hundred The final mass, g 413 437 Feed costs, kg / kg 0.9 0.85 The output, kg / m ³ 68 80,4

Claims (1)

A method of growing salable fish in a closed-water supply fish breeding unit, which involves the use of a variable temperature regime of water, characterized in that an astatic temperature regime with a thermoperiod of 24 hours is used for growing clary catfish, and in the daytime from 8 to 16 hours the temperature is increased from 24 to 30 ° C, and from 16 to 8 hours lower from 30 to 24 ° C.