RU1784146C - Method for decapsulating the eggs of crustacean acfemia salina sp - Google Patents

Abstract

Usage: industrial fish farming, decapsulation of egg crustaceans. SUBSTANCE: decapsulating solution is prepared, which is a 7-day-old culture fluid of Verticium lecpnl fungus at an egg-decapsulating ratio of 10: 1. 3 tab.

Description

The invention relates to industrial fish farming, in particular to methods for preparing eggs of crustaceans for incubation, and can be used in the production of feed for fish larvae.

As a starting live food for feeding larvae of fish of different ages, the gill leg crab Artemia sallna (subc / cl, Branchlopoda, order Anostraca) is used. The resting (ranging) Artemia eggs are viable for many years and can be used at any time. The shell of artemia eggs consists of three layers: a hard chorion of gray and light brown color and an internal transparent embryonic cuticle. After dissolution of the chitin-like chorin, the embryo remains in a thin elastic cuticle, which is easily absorbed by fish larvae.

Known methods for preparing and incubating artemia eggs, when the percentage of hatching nauplii increases. For this, egg incubation is used for various periods of exposure in solutions of organic solvents such as acetone, xylene, as well as in solutions of soda, borax, sodium chloride, peroxide, etc. The listed methods allow increasing the hatching of brine shrimp, however, non-hacked eggs and empty shells consumed by fish larvae are not digested and block the intestines. Mechanical separation does not produce the desired effect. In this regard, it becomes necessary to develop methods for decapsulating artemia eggs. The advantage of decapsulation is disinfection, an increase in the percentage of hatching of nauplii, the conservation of energy (calorific value) of the embryos, which do not expend efforts on breaking the chorion

A known method for decapsulation of eggs of brine shrimp, when bleach is usually used as a decapsulating agent

00

b.

ABOUT

and calcium and sodium hypochlorites. The chlorine activity of the decapsulated solution is 28 g / l. In 1 l of the solution, 80 g of eggs are treated for 10-15 minutes, with stirring, pH 10. After decapulation, the eggs are washed in water and treated with decimolar hydrochloric acid to deactivate the remaining chlorine. The hatching efficiency of nauplii from treated eggs is 11–17% higher than from untreated eggs. The effectiveness of the reagent varies depending on the amount of active chlorine in it, however, during storage, the content of active chlorine changes and additional conversion is necessary to determine the actual chlorine content in the reagent before use.

However, this method, due to the excessively high content of active chlorine, as well as its prolonged exposure, have a negative effect on the decapsulation of eggs, and a decrease in exposure does not provide complete decapsulation. In addition, storing reagents, preparing a de-encapsulating solution, then rinsing Artemia eggs from it, deactivating chlorine with acid, creates an increased risk to personnel and the environment.

For humans, chlorine derivatives are toxic - the concentration of glutathione in the blood decreases, DNA synthesis in some organs is inhibited.

The closest in technical essence and the achieved result is the described method.

The aim of the invention is to increase the efficiency of the process.

To achieve the goal, according to the method of decapsulation of eggs of hertemia. including preparation of a decapsulating solution containing a 7-day culture fluid (CL) of Verticlllium lecani 71t fungus with chitinase activity, followed by processing of eggs of this CL, while Artemia eggs and decapsulating solution are taken in a weight ratio of 10: 1.

The proposed method for decapsulating Artemia eggs is as follows.

The collected eggs of the Artemla sallna crustacean are cleaned of impurities and placed in water for their gadration for 1 hour. After that, the eggs are filtered in a bag of nylon gas.

A decapsulating solution is pre-prepared. For this, the liquid was previously sterilized at P-0.5 atm for 30 minutes Chapek's medium; sucrose - 30 g, potassium nitrate - 3 g, potassium

monosubstituted phosphate - 1 g, magnesium sulfate - 0.5 g, potassium chloride - 0.5 g, iron sulfate - 0.01 g, distilled water - 1 liter, pH

 5.5-6.0 - was inoculated with the fungus Verticillium lecani Zfm. The fungus was cultured by the surface method in liter flasks containing 200 ml of culture medium. Cultivation Mode:

at t + 24 ° C for 7 days in a thermostat. The culture fluid is then filtered off and serves as a decapsulating solution of artemia eggs.

Hydrated eggs are placed in

the solution at a temperature and kept in it for 1-2 hours with stirring. After that, the eggs are removed from the solution, washed in fresh water for 5 minutes and laid for incubation according to the known

methodology.

The action of the decapsulating solution is based on the fact that during the growth of the V.lecani QOL fungus exoenzymes of chitinosis with chitinase activity accumulate.

The strain of the fungus Verticillium lecani Zlm under N; 6 deposited at the All-Russian Research Institute for Plant Protection as a producer of an entomocidal fungal preparation harmless to warm-blooded

and the environment.

In the proposed technological process, the ratio of the mass of eggs and decapsulating solution is 10: 1 (Table 1), with an increase in the ratio of eggs and solution

the percentage of decapsulated eggs is lower. An increase in the amount of decapsulating solution per unit of eggs leads to an unreasonably high consumption of culture fluid, and the percentage of decapsulated eggs in the range close to fc is 10: 1. With a decrease in the amount of decapsulating solution per unit of eggs, the culture fluid is not enough for the whole

the volume of eggs processed and the percentage of decapsulated eggs are significantly reduced. Processing time of at least 1 h (Table 2). With a longer exposure, the process is impractical, because

quality itts.

Egg processing is carried out at room temperature (18-20 ° C), which corresponds to the temperature that occurs under conditions of fish farming in warm waters.

As a decapsulating solution, a 7-day culture fluid is optimal (Table 3). The culture fluid can be frozen. When thawing after 30 days in cold storage

lodilnik, its decapsulating properties did not deteriorate (Table 3).

Claims (1)

Of the decapsulated eggs, a 100% yield of viable nauplii was noted / Formula of the invention A method for decapsulating eggs of crustaceans Artemia salina, involving the preparation of a decapsulating solution and subsequent processing obtained 0 egg solution, characterized in that, in order to increase the efficiency of the process, the culture liquid obtained after 7-day growth of the fungus Vertlcilliumlecanf is used as a decapsulating solution, while the egg is treated with an egg liquid in a weight ratio of 10 to 1 egg-fluid. Table 1 Effect of A. salina eggs concentration in decapsulating decapsulation solution (processing time 1 h, 7-day culture fluid) Effect of decapsulating processing time solution for decapsulation of A.salina eggs (10 mg egg / 1 ml solution) The influence of the time of cultivation of V. lecani in a nutrient medium on its decapsulating properties (egg processing time 1 h) table 2 Table 3