SU1472014A1 - Method of determining optimized duties of growing young fish - Google Patents

Abstract

This invention relates to fish farming and is aimed at determining the most effective temperature or salinity when feeding fish. For this, young groups are placed in tanks with specified parameters of temperature or salinity and fed to saturation. After a certain time, the fish are weighed and an absolute daily increment is found. In parallel, the intensity of oxygen consumption in fry of fish in the respirometer is determined at the same temperature and salinity. The sum of the energy costs is determined by the formula ΣQ = 4.86 ^{. B. T.} P, where, ΣQ - total energy costs, cal

B is the intensity of oxygen consumption, ml O ₂ / g ^. day

T is the time required for weight gain per day

P is the mass of fish, g

4,86 - oxycaloric coefficient. According to the obtained values of ΣQ, a graph is constructed that looks like a parabola. The optimal temperature or salinity regime is defined as the vertex of a parabola by the formula F _o = b / 2a, where b, a are the coefficients, which are calculated by the least squares method, based on the ΣQ values. 2il., 2 tab.

Description

The invention relates to fish farming, in particular to methods for determining optimal breeding conditions, and can be used in growing fish.

The aim of the invention is to determine the values of temperature or salinity at which feeding the young fry will be most effective. Firstly, it reduces feed consumption when raising fish per unit of production by eliminating unproductive

energy consumption l, secondly, to reduce the mortality and morbidity of fish, i.e. increase their survival rate.

The method is dried as follows.

Young fish in groups are placed in separate containers with given temperature or salinity parameters, for which it is necessary to establish the optimum regime for the growth of young fry. Juvenile fish are pre-weighed. Each tank is kept constant

temperature or salinity. Juveniles measles to saturation. After a time sufficient to establish a reliable weight gain, the fish are weighed and the absolute daily gain is determined. In parallel, the intensity of oxygen consumption in fry of fish in the respirometer is determined at the same temperature and salinity. The amount of energy costs is determined by the formula

Q 4.86-V.Т.Р, (1)

where 51Q is the total energy cost,

feces; W.- consumption rate

oxygen, ml O / g-day; T - time for which received

increment, days; P is the mass of fish, g; 4,86 - oxaloric coefficient

According to the obtained values of 21Q, the traffic builds up the dependence of the total energy consumption for growth on temperature or salinity. This dependence has the form of a parabola and is determined by the formula

XQ a9 + bf + c.

(2)

where F is the value of the factor under study (temperature or salinity);

a, are the coefficients that are ra b, are calculated by the method of least squares, the outcome

from the SIQ values calculated by the formula (1).

The optimal mode for a given factor is determined by the formula

F -L about 2a

The method is based on using the property according to which any living organism, when adapting to a given factor, spends less energy in optimal conditions. With a deviation from the optimal mode in one direction or another, the energy consumption of the organism for development and growth sharply increases.

Example 1. They took 30 pieces of young salmon weighing 100 + 2 g each, weighed and placed in containers, each of which was constantly maintained at a temperature of 4 | eight; 12; 14; 18 ° C. Feeding while keeping fry was carried out to saturation. At the same time, the intensity of oxygen consumption by an eggfish of the same mass under the same temperature conditions was measured by the polarographic method, having previously acclimated the fish for 5 days to a given temperature regime. Fishes, in which the intensity of oxygen-oxygen consumption was varied, were placed in breathers, where water with a known oxygen content was fed. Changes in oxygen content due to fish respiration

measured with an oxygen electrode and

fixed on the recorder. After 20 days (time sufficient for reliable changes in body weight) weighed and calculated the time

necessary to increase 1 g of body weight. According to the data obtained, the total energy expenditure required for the growth of 1 g of body weight (2Q) was determined at all the temperature regimes used in the experiment using formula (1). In tab. 1 shows the primary data necessary for calculating 21Q. Juvenile salmon weighing 100 g, acclimi

to water with a temperature regime in the range of 4-18 C.

FIG. 1 shows a graph of the temperature dependence of the environment, based on the data presented in Table. 1 and approximated by the parabola equation

Q 13,71t - 346, Ot ° + 3125, where t is the water temperature.

l 40

The top of the parabola, defined by the formula (3) (346.0 / 2 x 13.71), corresponds to 12.6 ° C. This is the optimal temperature at this stage of development, at which the nourishment will be most effective (the maximum increment per unit of feed consumed will be obtained).

Example 2. They lied on 30 pieces of young chum salmon with an average weight of 3.0 + 0.4 g, weighed and placed in containers, 13 of which each maintained constant water salinity: 0; 6; 12; 18; 24; 30% C. Feeding during the growth was carried out until complete saturation. Analogously to example 1, the intensity of oxygen consumption was determined and the total energy expenditures required for a gain of 1 g of body weight were calculated.

50

55

In tab. 2 shows the primary data necessary for calculating 51Q in young chum salmon with an average mass of 3 g acclimated to water with a salinity regime in the range of 0-30% o.

FIG. 2 shows a graph of the dependence of 2 on the salinity of the medium, constructed on the basis of the data presented in Table 2 and approximated by the equation of a parabola.

Q 20.0252 - 445.78 + 3389.4, where S is the water salinity in% o.

The minimum of the obtained parabola corresponds to 11.1% of l. This is optimal for this stage of development, the salinity of water at which feeding will be most effective.

Claims (1)

Invention Formula The method of determining the optimal regimes of fish rearing, which includes holding individual groups of fish in water with different values of salinity or temperature, determining the intensity of oxygen consumption and establishing the conditions most five 0 five advantageous for their improvement, characterized in that, in order to determine the values of temperature and salinity at which feeding will be most effective, the fish in the process of feeding are fed to full saturation, along with the intensity of oxygen consumption, the magnitude of the increase is determined over a predetermined time interval in each group and calculate the total energy consumption by the formula 5: 0 4.86-AT-T, where 5IQ sumarny energy consumed, feces; B - consumption rate oxygen, ml O / g-day; T - the time for which increment, days; P is the mass of fish, g; 4,86 - oxaloric coefficient, then the values obtained are approximated by the parabola equation and the conditions most favorable for growing are determined as the vertex of the parabola. Table 1 table 2 i500 rooo 25