RU2365105C1 - Method of artificial breeding of shellfish - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: method presupposes fishing out of roed females and their transportation, storage in the pool at optimal conditions until maggots hatch out and their growth. Females are transported in capacities at 85-90% humidity and at a temperature plus 3 - plus 4°C. Before putting females into the pool, they are kept in capacities with water temperature plus 3 - plus 4°C and population density 2-4 units/m² within 3-5 days. Thereafter females are put into the pools, separated by a perforated partition into two chambers. One chamber for females contains lightproof lid, the other source of light and pipeline for maggots bypassing. One-two females are put into each pool. Oxygen level in the water is secured of not less than 90% and saltiness not less than 32%. After the onset of hatching out lighting is switched on. Under positive phototaxis effect maggots get through the perforated partition into the second chamber for further transportation through the pipeline into capacities for growth.

EFFECT: increased throughput and survival rate of maggots.

2 dwg, 1 ex

Description

The invention relates to the fishing industry, namely the reproduction of marine crustaceans. Lithodes, Order Decapoda, Suborder Anomura, fam. Lithodidae, genus Paralithodes, Paralithodes camtschaticus.

A known method of reproduction of crab, including the collection of crab larvae, which is carried out on collectors, on collector-cage systems or on cages, which are exposed to depths of 5-150 m in sea areas with a water temperature of not higher than 18 ° C, salinity of not lower than 28% s the content of dissolved oxygen in water is not less than 5 mg / l. Growing fry is from 4 months to 3 years (see RF patent 2174750, A01K 61/00).

The disadvantage of this method is that reproduction is carried out in vivo, without strict control and the ability to optimize the environmental conditions and feeding regime, which ultimately determines the survival of the larvae.

There is a method of reproduction of crustaceans, presented in biotechnology recommended when receiving planting material for king crab in a pilot installation. The developed installation with a closed water supply system makes it possible to control and maintain specified environmental parameters (illumination, temperature, salinity, oxygen content, pH, redox potential). (see Stepanov D.N., Smirnov B.P., 1999. Pilot plant for receiving planting material for Kamchatka crab. / Fisheries: Aquaculture series: Information package "Aquaculture: problems and achievements" / VNIERKh, issue 2. - C .10-14).

The disadvantage of this work is that the pilot installation did not pass testing with obtaining larvae and juveniles until viable stages. Of the 3 Kamchatka crab females delivered from Vladivostok in April 1998, one female dropped eggs during transportation, while the other two showed abortive hatching of larvae a day after delivery. All larvae died within 3-4 days. The proposed biotechnology has several disadvantages: the conditions and optimal feeding conditions for each stage of development have not been worked out. The planting density of 100 pcs / l proposed by the authors has not been verified and does not meet the biological characteristics of the larvae (cannibalism is highly developed).

A known method of reproduction of king crab is that females with eggs at the last embryonic stage (5-10 days before hatching of larvae) are transported to the incubation site with constant aeration and planting density of 10-12 pcs / m ² . At the same time, the duration of transportation should not exceed 15 hours. The content of females before hatching of larvae is carried out in pools with a closed water supply system at a planting density of not more than 2 pcs / m ² , water flow rate of at least 5 l / min, water temperature of not higher than 4 ° C, pH in the range of 7.9-8.1, salinity 30-32 ‰. From the beginning of hatching, the water temperature gradually rises (1 ° С / day) to 7-8 ° С. The start of hatching is calculated in advance by changing the ratio of the area of the yolk to the entire area of the egg. The hatching of larvae from one female ranges from 3 to 7 days. Hatching larvae miscalculate and are daily transferred to outgrowth pools. To collect the larvae, their phototaxis reaction is used. Further growing of larvae (zoea) is carried out in pools with a closed water supply system at a planting density of not more than 50 pcs / l, flow rate of at least 1 l / min, at a water temperature of 7-9 ° C, pH in the range of 7.9-8 , 2, oxygen saturation of water of at least 80%. During the larval period of development of zoea, 4 stages pass. Kamchatka crab already has cannibalism in the early larval stages. In this regard, a landing density of not more than 50 pcs / l and timely and sufficient provision of live food is observed.

The technical task of the claimed invention is to increase the yield and survival of the larvae by optimizing the conditions for the implementation of the method, including reducing the level of injury and mortality of the larvae.

The problem is solved in the implementation of the method of artificial reproduction of crustaceans, including the capture of eggs, their transportation, keeping in the pool under optimal conditions until hatching of larvae and growing larvae, the transportation of females is carried out in containers with a humidity of 85-90% and a temperature of plus 3 - plus 4 ° C, before landing in the pool, the females are kept in containers with a water temperature of plus 3 - plus 4 ° C and a planting density of 2-4 individuals / m for 3-5 days, followed by landing of the females in the pools, separated by perforated a partition into two compartments, one of which is provided for females with a lightproof cover, the other with a light source and a larval drainage pipe, and one or two females are planted in each pool, the oxygen content in the water provides at least 90% and the salinity is not more than 32 ‰, after hatching starts, the lights are turned on, under the influence of positive phototaxis, the larvae penetrate through the perforated septum into the second compartment for subsequent transportation through the pipeline to the growth containers.

The method is as follows.

Females are caught in the 2nd decade of April (in the Far East) or in January-February (in the Barents Sea), weighing 1.5 kg, and a carapace of about 15 cm. Caught females are brought ashore in tanks with a flowing water supply system , aeration, temperature control, in individual sectors. Females are selected according to the maturity of the eggs of the corresponding degree of “eye”. Selected females are transported to the place of work in special containers without water, with a humidity of 85-90% and a temperature of plus 3 - plus 4 ° C.

Adaptation to conditions of detention and quarantine. Upon arrival at the place of detention, the females are placed in special quarantine tanks to adapt to the conditions of detention and selection of weak individuals, the tanks set the water temperature plus 3 - plus 4 ° C, planting density 2-4 specimens / m, incubated for 3-5 days .

Prior to hatching, the larvae of females are placed in pools separated by a perforated partition into two compartments, one of which is provided with a lightproof cover for females, the other is provided with a light source and a larval drainage pipe, with one or two females planted in each pool, the oxygen content in water provide not less than 90% and salinity not more than 32 ‰.

The containers are made in the form of a structure (Fig. 1, 2, Fig. 1, A is a top view, Fig. 2, B is a side view) of a rectangular shape. The device has: an isothermal tank 1, a partition 2 perforated to the size of a larva, a transparent pipe section 3, an aerator 4, a crane 5, a protective mesh with a fine mesh 6, a technological drain 7, a light source 8, a larva counter 9, a lightproof cover 10, the proposed level water 11.

Design features of the container for keeping and spawning females:

- The bottom with the presence of a bottom topography in the form of: a microrelief providing the necessary adhesion of the crab limbs to the bottom.

- The presence of a protective device at the sink.

- Pipelines for aeration from a special material are located around the perimeter of the bottom of the tank along the sides, as well as around the drain.

- The color of the bottom of the tank is dark.

- Shape of the container: rounded rectangle.

- Drain design, providing fast and simultaneously controlled water discharge.

- The presence of a perforated partition dividing the capacity into 2 compartments at the rate of 2/3 to 1/3.

- The presence of a lightproof separate cover.

- The presence of a transparent section of the pipeline with a source for the distribution of larvae in outgrowth capacities of light.

The tank is installed above the water level in outgrowth tanks for larvae. The compartment in which the female is located is covered with an opaque lid, while the rest of the tank is illuminated by general lighting in the room. In the process of hatching, the larvae through the perforated septum tend from the dark part of the tank to the illuminated one and remain there. After hatching is completed or, if necessary, a certain number of larvae are moved, the container is completely isolated from light, after switching on the illumination of the transparent section of the pipeline. Under the influence of positive phototaxis, a larva rushes into the pipeline and when the tap is opened with the help of a current of water, it is distributed among the growing containers. Next, the flow of water with the larva is fed to the meter and, with the help of a flexible hose, is distributed in the tank.

Upon completion of spawning, females are removed from the pools, placed in shipping containers and taken to the place of release.

An example implementation of the method.

Females were caught in the Far East in the 2nd decade of April, weighing 1.5 kg, and a carapace of about 15 cm. Caught females were brought ashore in tanks with a running water supply system, aeration, temperature control, and in individual sectors. Females are selected according to the maturity of the eggs of the corresponding degree of “eye”. Selected females are transported to the place of work in special containers without water, with a humidity of 85% and a temperature of + 3 ° C. Then the females are planted in special quarantine tanks to adapt to the conditions of keeping and selection of weak individuals, in the tanks they set the water temperature plus 4 ° C, the planting density of 2 ind / m, incubated for 5 days.

Prior to hatching, the larvae of females are placed in pools separated by a perforated partition into two compartments, one of which is provided for females with a lightproof cover, the other with a light source and a larval drainage pipe. One female is planted in each pool, the oxygen content in the water provides no less than 90% and salinity no more than 32 ‰. After hatching starts, the lighting is turned on, under the influence of positive phototaxis, the larvae penetrate through the perforated septum into the second compartment for subsequent transportation through the pipeline to the growth tanks.

Claims (1)

A method for the artificial reproduction of crustaceans, including catching eggs of females, their transportation, keeping in a pool under optimal conditions until hatching of larvae and growing larvae, characterized in that the transportation of females is carried out in containers with a humidity of 85-90% and a temperature of 3 - 4 ° C, before planting in females pool is kept in tanks with water temperature 3 - 4 ° C and the density of planting 2-4 copies / m ² for 3-5 days, followed by planting in females basins separated by a perforated partition into two compartments, one of which d I am a female, provided with a lightproof cover, the other with a light source and a larval drainage pipe, at that, one or two females are planted in each pool, the oxygen content in the water is not less than 90% and the salinity is not more than 32 ‰, after the start of hatching, the lights are turned on, under the influence of positive phototaxis, the larvae penetrate through the perforated septum into the second compartment for subsequent transportation through the pipeline to outgrowth containers.

Images