SU1393374A1 - Method of growing mozambique tylan - Google Patents

Abstract

The invention relates to fish farming, in particular to methods of breeding. Mozambican ti fi van in warm-water systems with a closed water supply cycle and is aimed at increasing the consumption of commodity production by increasing the number of regenerations in females. This is achieved by reproducing active males for 40 days to create broodstock, spawning and, on the 5th day after spawning, females of free embryos are forcibly removed from the mouth, harvested to float, fry are grown and commercial products. At the same time, the number of females decreases 4-5 times, the area of the bottom, necessary for their reproduction, decreases 20-25 times. 2 tab. i SL

Description

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The invention relates to fish farming and can be used for growing tel bodies in warm-water systems with a closed water supply cycle.

The aim of the invention is to increase the yield of marketable products by achieving its multiple production under the conditions of closed recycling systems.

Due to an increase in the number of spawns in females, the number of broodstock, the tilpium is reduced by 4-5 times, and the area of the bottom is also reduced by 20-25 times, which is necessary for their reproduction. In the way the reproduction of producers, the production of planting material and commercial product occur simultaneously.

The essence of the method of growing Mozambique breeds lies in the fact that reproductively active males are selected during the observation period of their spawning activity for 40 days to create broodstock, i.e. period, a multiple of two units of spawning time. The duration of the period is due to the biological characteristics of the female's sex cycles, the spawning intervals of which are 20 days. Reproductively acted | Tivnymi are considered males that participated in spawning 4 or more times. Then the selected reproductively active males are placed in the capacity of the system with temperature, where the spawning takes place. After spawning, on the 5th day, Mozambican female free embryos are forcibly removed from the oral cavity and placed in Weiss machines with a working volume of 1 l, where they are held until they melt. Then, the larvae are transferred to the tank of the recirculation system, where they are grown to hinge the fry of planting material, after which they are transferred to commercial pools in the basins of the recirculation system.

The method of enhancing Mozambican print allows the fullest use of the potential reproductive potential and high ecological plasticity of print. Types with a content in the recirculation system under stable hydrochemical conditions multiply in

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circulation water 27 s.

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throughout the year with the same intensity. However, due to the ecological characteristics - carrying the eggs and the offspring in the mouth - during incubation of the eggs and nursing the larvae in the mouth, the females either do not nourish at all, or, if fed, it is very limited, which is reflected in flow rates of oogones in these. spawning fish portions.

Thus, in order to stimulate the reproduction of Mozambican females, it is necessary to exclude from the reproductive cycle the incubation phase of the eggs and, partly, the breeding phase of the larvae in the oral cavity.

The duration of testing males for reproductive activity (40 days) is explained by the fact that observing males for a shorter period of time may lead to

not all females in the group spawn ts I

during this period, the reproductive quality of the males will be determined incorrectly (understated), the delay of the observation period over 40 days. It is also impractical, since in this gonad degenerative changes in the sexual products may occur, i.e. females overripe without spawning on time, due to the low reproductive activity of the male in this case, for example. In order to form broodstock in seven aquariums, re-tempo - seven sexually mature males and six sexually mature females in each tank. The period of observation of the spawning activity of fish is 40 days. After evaluating the breeding activity of males over this observation period, it was established that males No. 1-4 and 6 participated in spawning five or more times, male No. 7 participated in spawning four times and male No. 5 participated in spawning two times.

Six females and male No. 1 were placed in aquarium No. 1 and monitored for 146 days. The number of spawns during the observation period was 38.

In the aquarium number 2 placed six females and male number 2 and watched them for 146 days. The number of spawns during the observation period was 39.

Six females and male fr 3 were placed in aquarium No. 3 and monitored for circulation in a circulatory system with a pool of water of 27 ° C.

93 days The number of spawns during the observation period was 26.

Six females and male No. 4 were placed in aquarium No. 4 and watched them during those 93 days. The number of spawns during the observation period was 25.

Six females and male No. 7 were placed in aquarium No. 5 and observed for 93 days. The number of spawns during the observation period was 28.

Six females and male No. 5 were placed in the K 6 aquarium and observed for 93 days. The number of spawns during the observation period was 18.

Males 1–4 and 7 took part in the spawning. After spawning, females forcibly removed eggs from the oral cavity on the 1st and 3rd day and on the 5th and 6th days of free embryos and placed them in Weiss machines with a working volume of 1 l.

The release of larvae after the forced extraction of eggs from the female's mouth on the 1st and 3rd day after spawning is shown in Table 1. , - I Ivkivaemosti larvae after forced extraction of free embryos from the female's oral cavity on the 5th and 6th day after spawning are shown in table 2,

From Table 1 and 2 it follows that the largest yield of larvae was obtained when forcedly removed.

the average duration of the interval between spawning in females to 20 days.

The natural interruption of the contact of females with offspring on the 17th day shows that the interval between spawning females is 27 days.

Thus, artificial interruption of the offspring phase of the offspring on the 5th day, when the maximum larvae yield is observed, leads to a shortening of the interval of water intervals by seven days compared with intact individuals.

After the free embryos become molten, they are removed from the Weiss apparatus and transferred to the basins of the recirculation system, where they are grown to a mass of commodities.

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Claims (1)

Invention Formula A method for attaining Mozambican ti-fi, consisting in forming a research institute of broodstock with an optimal sex ratio of producers, keeping them in a recirculation system, spawning, getting larvae, growing them to hinge planting material and transferring fry to commercial breeding in pools, characterized by , in order to increase the output of marketable products by achieving free embryos from the oral band - 35 multiple production at the rate of the female on the 5th day after spawning. Artificially interrupting the incubation of eggs on the 1st day after spawning leads to a significant reduction in the average duration of the interval between spawning in females to 19 days. Artificial termination of the incubation of eggs on the 3rd day after spawning leads to a significant reduction in the average duration of the interval between spawning in females to 19 days. Artificially interrupting the procreation phase of the offspring on the 5th day after hatching of free embryos leads to a significant reduction SWITCHES of closed recirculation systems, in the formation of broodstock, reproductively active males are preselected, for which males are kept together with females for 40 days, their spawning activity is recorded. and reproductively active include those males who participated in the spawning at least 4 times, and after trying to spawn to obtain a larva in females, artificially interrupt the procreation phase of the offspring on the 5th day and free embryos obtained in this way are kept in incubation devices until becoming float. Table 1 405 38A table 2 389 365 96 95