Artificial Propagation and spawning Technology of Monopterus Albus

Monopterus Albus belongs to hermaphrodites, tropical and warm temperate fish, benthic fish, strong adaptability, can survive in rivers, lakes, ditches and rice fields, and has high breeding value. The reproductive season is saved from May to August. It has the characteristics of male and female reversal in its ontogeny, so let's take a look at the techniques of artificial reproduction of Monopterus Albus.

Dosage of oxytocin

It is suitable to use luteinizing hormone releasing hormone analogue (LRH-A) at a dose of 0.1 μ g / g body weight. Chorionic gonadotropin (HCG) at a dose of 1kg / g body weight is effective to induce ovulation, but 2: 3 international unit / g body weight is the most suitable. The inducing effect of Monopterus Albus on LRH-An and HCG was also closely related to the gonadal maturity. Shortly after the beginning of the breeding season in early May, the effect of hormone on ovulation was not obvious. From June to July, the hormone had an obvious effect on inducing ovulation. In August, the ovary gradually degenerated, the response to hormones weakened, and the effect of ovulation induction was poor. Therefore, the dose of induced labor should be increased or decreased at different time according to the mature degree of ovary, and the dose of male eel is 1 / 2 of that of female eel.

Effect time

The effect time of induced spawning of Monopterus Albus with LRH-An or HCG was 1 to 5 days. The effect time was not related to the dose of induced labor, but related to the water temperature and injection times. The effect time was about 40 hours when the water temperature was 30 ℃, while it was more than 50 hours when the water temperature was lower than 27 ℃. When the same dose of LRH-A was used to induce labor at the water temperature of 23 ℃, the effect time of one injection was 83-160 hours, while that of two injections could be shortened to 23-81 hours.

Preparation of oxytocin

LRH-An and HCG are white crystals, which are fully dissolved in normal saline solution. The dose is accurately calculated according to LRH-A0.3 microgram / gram body weight + HCG2~3 international unit / gram body weight and inhaled into the syringe. The injection volume of each parent eel should be 0.5 ml, not more than 1 ml. The injection should be used with you and should not be kept for too long. After the first injection, the remaining liquid can be placed in the refrigerator and can be reused when the next injection is given. If there is no refrigerator, the second injection should be reformulated.

Injection method

Use 5 10 ml medical syringe, 4 # 6 needle, the syringe should be boiled and sterilized for 10 minutes or disinfected with alcohol. There are two kinds of injection: intraperitoneal injection and thoracic injection. Because of the slender body and small chest cavity of Monopterus Albus, it is generally appropriate to use abdominal ovarian injection, and the effect is faster. During the injection, two people should cooperate. One person holds the rice field eel with a towel or gauze to make the abdomen face up, cushion the eel with a towel below, fix the eel with both hands, and the other person dries the water at the injection site. The needle is placed in the direction of the eel head, at an angle of 45 to 60 degrees with the fish body, and the needle is pierced into the abdominal cavity at a depth of no more than 0.5 cm. The injection is slowly pushed into the abdominal cavity of the eel, and when the needle is pulled out, it is pressed on the needle eye with an alcohol cotton ball. Gently knead to prevent the injection from flowing out, which can also play a role in disinfection. The needle should not be inserted too deep to avoid stabbing the internal organs, but it should not be too shallow, otherwise the liquid cannot enter the abdominal cavity.