Complete artificial breeding trial of Olia tilapia

Oria tilapia has low requirements for reproductive conditions, has the characteristics of early sexual maturity and short spawning cycle. As long as the temperature is suitable, it can reproduce multiple times a year in a small area of ​​still water. It is relatively easy to obtain a large number of seedlings in production. Therefore, few people have conducted artificial breeding research on it. 1.1Source and cultivation of broodstock
Before stocking the broodstock, fermented manure 250~500kg should be applied per acre. After the broodstock is cultured and put into the pond, artificial feed such as cake meal, bran, and compound feed should be fed. The daily feed amount is about 5% of the fish's body weight. The spawning pool is a 1.2m×0.8m×1.0m glass water cluster box, and the pool water is tap water with aeration of 3d or above. There are three holes in the abdomen of female fish, namely the anus, genital pore and urinary pore. The urinary pore is at the top of the genital process. The genital pore is opened between the anus and the urinary pore. It is a narrow and long opening in the shape of " and is perpendicular to the genital process. 1.4Induced labor and artificial insemination
The broodstock after induction of labor are placed in water cluster boxes with a male-to-female ratio of 1:1, and 5~7 are placed in each water cluster box. For broodstock, an aeration pump is used to increase oxygen for 24h. Transfer the fertilized eggs to a petri dish or a culture tank for static water incubation. Place 50～100 eggs in each petri dish, and place 200～1.6Fry fry cultivation
2Results
From 5 month 30 to 8 month 13 day, every day 2.2Effect time and spawning behavior
While the female fish is making a nest, there are often male fish biting, chasing, and spinning around with her until the female fish lays eggs and the male fish releases sperm. The long diameter of the egg is 2.06～2.40mm, and the wide diameter is 1.53～1.80mm. The diameter of the egg varies with the size of the parent fish. When the water temperature is 26～28℃, the incubation time of fertilized eggs is 78～90h, and the accumulated temperature during the entire embryonic development period is about 2100℃.h. 3Discussion and Analysis
In addition, during the peak breeding period (from the beginning of June to the end of July), more broodstock can also be selected. It is difficult to grasp the time of the artificial induction effect of Olia tilapia. The time of the effect of artificial induction of labor on the selected female broodstock varies greatly. This may be due to the fact that they spawn multiple times a year and have inconsistent gonad development. When these two characteristics are found, it means that the effect time is approaching and eggs may be laid at any time, so special attention should be paid at this time.