How to accurately distinguish the male and female of Monopterus Albus

shape

Female head is small not raised, back is green-brown, no striped flower spots, sometimes can see 3 parallel brown spots, body color gradually lighter from top to bottom, brown spots fine and evenly distributed; abdomen is pale yellow or pale green, abdominal muscle is thin. The male head is larger than the female and slightly raised. The back is generally formed by brown spots with three equal striations. A line of pigment bands can be seen along the midline on both sides of the body, and the rest of the pigment spots are evenly distributed. The abdomen is khaki, the individual is orange, and the abdomen is upward, and the expansion is not obvious.

growth cycle

Monopterus albus has sex reversal, all young monopterus albus are female at the initial stage, and become male after spawning; when the body length is 24 cm, sex reversal begins and it is hermaphroditic.

Characteristics of breeding season

Female eel abdomen translucent pink, intra-abdominal eggs visible, swollen, genital pores red, swollen, slightly transparent; male eel abdomen distribution of reticular blood, no prominent feeling, genital pores red, slightly prominent.

individual differences

The individuals below 24 cm in length are all female; the individuals 24~30 cm, 30~36 cm and 36~42 cm in length are male, accounting for 5.2%, 41.3% and 90.7% respectively; the individuals above 50 cm in length are all male.

age

Because of sufficient nutrition supply and different varieties, the cultivated eel has extraordinary body length, so it should be judged by age: generally, the eel within two years old is female, and the eel over three years old is male.