CATDOLL : CATDOLL: How to identify the quality of tilapia fry?

1. How to identify the quality of tilapia fry?

As the saying goes, "Good seeds produce good seedlings, and strong seedlings produce high yields." Only with strong fish seedlings (Figure 4), there will be a higher survival rate, faster growth rate and lower morbidity. The identification of fish seedlings is mainly based on the following aspects:

Figure 4 High-quality tilapia fry (1) Body color

High-quality fry have fresh and tender body color, slightly yellowish or slightly reddish, no dead white fry, and the fry group has roughly the same color; otherwise, they are low-quality fry. (2) Look at the activity ability

High-quality fry like to gather in groups, while low-quality fry like to swim alone. Hit the fry basin with your hands or insert a wooden stick into the middle of the fry pond to scare the fry. High-quality fry will swim quickly, while low-quality fry will react slowly. (3) Watch them swim against the current

Stir the water with your hands or a wooden lead rod to create a whirlpool. High-quality fish fry can swim upstream along the edge, while low-quality fish fry are sucked into the whirlpool and are unable to struggle. (4) Sampling inspection

Scoop the fish fry into a white porcelain basin, blow on the water surface with your mouth, the fry can swim against the wind, pour out the water, the fry struggle violently at the bottom of the basin, and bend their heads and tails into a circle, these are high-quality fry. If you blow on the water surface with your mouth, the fry swim with the water, and after pouring out the water, their struggle is weak, and their heads and tails can only tremble, these are low-quality fry.

2. What is off-season tilapia farming? What are the advantages?

Because tilapia is a tropical fish, it requires a water temperature of no less than 12°C to survive. In the main tilapia producing areas in my country, the stocking time of fry is generally from February to June, and the adult fish are put on the market from July to December. That is, they are released in the first half of the year and harvested in the second half of the year. The time of market launch is relatively concentrated, competition drives down prices, and it is difficult to improve breeding efficiency.

If, on the other hand, the harvest is done in the first half of the year and the stocking is done in the second half of the year, it is off-season farming. In addition, winter farming using hot spring water, waste water from power plants, heat preservation greenhouses, and various overwintering seed preservation models is also off-season farming. Off-season farming advances the time for adult fish to be put on the market in the first half of the year, avoiding the concentrated time for general farming, balancing market supply, obtaining the highest sales price of the year, and significantly improving farming efficiency. In addition to the overwintering hail-seepage farming model, off-season farming is mainly achieved by stocking large-sized overwintering fish species and shortening the farming cycle.

This article is from: China Agricultural Press "Encyclopedia of Animals and Plants"

3. Is it difficult to raise Ranchu fry?

It depends on your level. In fact, fry are the same as adult fish, but they are more susceptible to diseases, just like adults and children. If you are well prepared and fully equipped, it is actually very easy to raise them. What you need to pay attention to is that water is added every day to promote the growth of fry. Feed less and feed more frequently. If you don't have time, feed less. The oxygen pump must be turned on 24 hours a day. The rest is up to you. Of course, the quality of the fry is also very important. It is better to have less than bad fry.