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Animal Protection Division Li Hongjiang
Zhuhai Hailong Shunde team
It's the time of the annual raw fish fry again, and the survival rate has always been the most important problem in the whole breeding process, and the survival rate represents the success or failure of aquaculture.
For example, if the price of black sesame seeds is 400 yuan/10,000 yuan, the seed cost of 1 fish is 0.2 yuan, and the seed cost of 1 fish is 0.1 yuan. If the survival rate is high, whether you raise it yourself or sell it, you can hold the initiative in your own hands and strategize.
So, how should we label the seedlings in order to increase the success rate? We have summarized the five major levels of raw fish seedlings.
Level 1: Opening Level
Black sesame seeds are generally hatched out of the seedlings for about 5 days, at this time the fry survive by absorbing the yolk, and after the yolk is absorbed, they begin to look for biological bait, at this time they can only eat some small water spiders, rotifers, protozoa and other small biological bait.
Therefore, when cultivating biological bait, we must pay attention to the time of splashing the fermentation broth, splashing on the day of seedling, or 1 day in advance; too early will cause the biological bait to be too large, and the fry can not eat.
The second level: alkalinity off
Due to the small amount of feeding at the seedling stage, the bottom organic matter is less, the acid production is less, the pond is rich in algae, and the photosynthesis of algae leads to the water body is easy to be alkaline, and the fry are very sensitive to alkalinity, pH > 8.8, which may cause the death of the fry.
Therefore, during the period from black sesame to golden eye, we should focus on the pH issue. At 2 o'clock in the afternoon, the pH < 8.4 is relatively safe, and once the pH > 8.4, it should be treated in time!
The third level: the stress level
Black sesame seeds are very fragile when they first enter the pond, and any stress can be fatal to black sesame seeds. For example, sudden environmental changes, sudden heavy rainstorms, cooling weather, persistent high temperatures, or human manipulation may cause attrition of fish fry.
The fourth level: the weak eat the strong
In the yellow-headed stage, due to the difference in the physique of the fry themselves, the difference in size is getting bigger and bigger, and at this time, the teeth are full, and the fry will instinctively have the habit of eating big and small, which has become one of the problems that affect the survival rate most in the normal breeding process.
In response to this problem, we must take corresponding measures to reduce the phenomenon of eating too much and eating too little as much as possible.
To be fed
Look at the size of the belly of the tail fish to determine whether they are fed or not.
Sieve in time
It is recommended that about 8000 mouths should be sieved for the first time, and the sieve head should come out, and then sieve once every 5-7 days.
Level 5: Rhabdovirus level
Rhabdovirus mostly occurs after the yellow head, especially in the period of feeding chilled, the incidence is relatively high, and the large loss is the biggest pain point in the seedling stage. When the disease is severe, the attrition rate reaches 80%, and almost all the troops are wiped out.
First of all, it is clear that the virus problem can only be carried by the resistance of the fry themselves, and remember to use antibiotics and disinfection products with caution, which will cause secondary stress and increase losses.
Rhabdovirus treatment process
(1) Stop feeding for 1-2 meals;
(2) Splash to Lingkang + VC50, 1 group of 2 acres of water body;
(3) After resuming feeding, take Zhuankang + VC50 internally, 1 meal in 1 group, 2 meals in 1 day.
Once the virus problem appears, no matter how timely the treatment is, there will be some loss, which will delay the breeding plan and reduce the survival rate of breeding.
Therefore, in response to the virus problem, we should take the preventive route, enhance immunity, resist stress, and avoid the onset or onset of the disease but have less loss, even if the goal is achieved.
Rhabdovirus prophylaxis
After the yellow-headed stage, 1 group of Zhuanlingkang + VC50 per day, mixed with 3-4 meals, to enhance physical fitness and enhance immunity.
I wish all farmers and friends to pass the test, raise seedlings, raise fish, and make money!
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