RU-2861300-C1 - METHOD FOR OBTAINING EGGS FROM FEMALE STURGEONS

RU2861300C1RU 2861300 C1RU2861300 C1RU 2861300C1RU-2861300-C1

Abstract

FIELD: fish farming. SUBSTANCE: invention can be used for in vivo obtaining of eggs from female sturgeons. The method includes sequentially compressing the walls of the fish abdomen in the direction from the head to the genital opening and milking the eggs from the oviducts. Before repeated milking of eggs, a manual surgical spatula is inserted into the genital opening of the female, not along the median line, but somewhat laterally, with the narrow end to a depth of 4 cm in the direction of the oviducts, exerting a stimulating effect on them by irritating the walls of the oviducts by successively moving the spatula from bottom to top for 30 seconds without damaging the walls of the oviducts and the abdominal cavity. EFFECT: reducing the risk of infection when obtaining eggs from female sturgeons. 1 cl, 1 dwg

Inventors

Turchaninov Evgenii Aleksandrovich
Ponomarev Sergei Vladimirovich
Akhmedzhanova Aliia Baimuratovna
Fedorovykh Iuliia Viktorovna
Levina Olga Aleksandrovna

Dates

Publication Date: 20260504
Application Date: 20251105

Claims (1)

A method for obtaining caviar from female sturgeons, which includes successive squeezing of the abdominal walls of the fish in the direction from the head to the genital opening and straining of the caviar from the oviducts, characterized in that before re-squeezing of the caviar, a hand surgical spatula is inserted with its narrow end into the genital opening of the female, not along the medial line, but somewhat laterally, to a depth of 4 cm in the direction of the oviducts, exerting a stimulating effect on them by irritating the walls of the oviducts by successive movements of the spatula from the bottom up for 30 seconds without damaging the walls of the oviducts and the abdominal cavity.

Description

The invention relates to fish farming, namely, to the artificial breeding of sturgeon fish, in particular to methods for the intravital production of caviar from female sturgeon fish while maintaining their reproductive potential. A known method for obtaining caviar from female sturgeons involves capturing the breeders, stimulating the maturation of the eggs with pituitary injections, opening the abdominal cavity by making an incision in the caudal part at a distance from the genital opening, extracting the eggs and suturing the abdomen with a surgical suture. The method is characterized in that the eggs are extracted at least 3 times, the first by opening the abdominal cavity, and the subsequent ones through the genital opening, at intervals of 0.5-2 hours, while during the opening, a C-shaped incision 3-4 cm long is made at a distance of 3-5 cm from the genital opening (see patent RU No. 2290704, 2007). The disadvantages of this method are: high invasiveness, long recovery time, risk of infection and a limited number of possible applications during the life of the female. The closest (prototype) to the claimed technical solution is a method for obtaining caviar from female sturgeon fish by successively squeezing the abdominal walls in the direction from the head to the genital opening and thus straining the caviar, characterized in that, in order to speed up the process of straining the caviar, before straining, a scalpel is inserted into the genital opening of the female and an incision is made in the caudal oviduct without damaging the wall of the abdominal cavity (see A.S. USSR No. 1412035, 2008). However, this method is traumatic, carries a risk of infection and disrupts the reproductive function of females. The technical result is an improved method for obtaining caviar from female sturgeon fish, reducing the risk of infection and preserving the breeders. The technical result is achieved by the fact that in the known method, which includes sequentially squeezing the walls of the fish's abdomen in the direction from the head to the genital opening and straining the eggs from the oviducts, before re-straining the eggs into the female's genital opening, not along the medial line, but somewhat laterally, a medical hand spatula is inserted with its narrow end to a depth of 4 cm in the direction of the oviducts, exerting a stimulating effect on them by irritating the walls of the oviducts by sequentially moving the spatula from the bottom up for 30 seconds without damaging the walls of the oviducts and the abdominal cavity. The anatomical structure of the urogenital excretory system of sturgeons differs from that of other fish species, therefore the proposed method is suitable specifically for sturgeons. The oviducts and vas deferens, the spawning ducts, do not communicate directly with the gonads but rather open into the body cavity through "funnels" with a check valve. These funnels are located in the caudal part of the body cavity and terminate in the genital opening. Ovulated eggs are released from the gonads and enter the body cavity, then through the funnels into the spawning ducts. They are released into the environment in small portions during spawning, a process that takes several hours and is labor-intensive and unsustainable. This reduces the quality of the final portion of eggs. The proposed method of batchwise extraction eliminates these drawbacks. The gentle manipulations used in the proposed method do not injure the fish and allow for repeated use of the producers. The method is carried out as follows. Females at stage IV maturity are captured from the hatchery's tanks, and egg maturation is stimulated with pituitary injections, such as pituitary gland suspension. The breeders are then kept in tanks at a constant temperature until maturation. Ovulation is determined by external signs, and egg collection begins. A container for the eggs is placed in a special nest under the operating table. The egg-straining procedure is performed by two people. The fish are placed belly-up on the operating table, with their caudal peduncle suspended. The abdomen and caudal peduncle are wiped with a dry towel to prevent water and mucus from entering the container. First, the eggs are strained from the oviducts. Before re-extracting the eggs, the narrow end of a medical hand spatula, used in this case for manipulating the oviducts, is inserted into the genital opening located caudal to the anus to a depth of 4 cm toward the oviducts. This spatula stimulates the oviduct walls by sequentially moving the spatula upwards for 30 seconds, without damaging the oviduct walls or the abdominal cavity. Simultaneously, the depth of insertion of the medical spatula into the female's genital opening and the stimulating effect are monitored using ultrasound. The gentle manipulations performed during the process of extracting the eggs do not adversely affect the spawners, preserve their natural spawning ability, and act as a