CATDOLL : CATDOLL: Causes of death of silver carp

Causes of death of silver carp

Recently, fish farmers have been asking about the silver carp in their ponds that have been dying. They have used a lot of medicines but none of them worked. What is going on ? What is the reason?

Causes of death of silver carp:

1. Death due to secondary infection with water mold, branchial mold and red skin disease. Users stocked silver carp fingerlings late, and some even continued until mid-April. Due to the high water temperature when transferring to the pond, the fish fingerlings struggled and jumped frantically. During the picking, weighing and transportation process, the fish were seriously injured on the surface. After the injured silver carp was transferred to the pond, they did not receive timely and careful care, and the wounds were infected by fungi and bacteria, resulting in water mold, branchial mold and red skin disease.

2. Irregular external use of disinfectants causes silver carp to die due to lack of oxygen or poisoning. Fish farmers are accustomed to using conventional insecticides and disinfectants with increased dosages before and after the Qingming Festival. Highly toxic and high-residue drugs have a strong irritation to silver carp on the surface of the water due to excessive local concentrations, often causing silver carp to die of poisoning. For example: the insecticide trichlorfon will produce more toxic dichlorvos in alkaline water; pyrethroid insecticides also have a greater irritation to the nerves of fish, and a slight overdose can also cause fish poisoning and death.

3. The heavy metal drug copper sulfate kills ciliates and also kills beneficial plankton in the water, resulting in a lack of palatable bait for silver carp. Chlorine disinfectants such as strong chlorine and chlorine dioxide also have a significant irritating effect on fish and plankton. After each routine insecticide, silver carp suffers from chronic poisoning due to drug stimulation, and the large-scale death of plankton causes thin water.

4. If silver carp is in a state of hunger, hypoxia and drug stimulation for a long time, its growth will stagnate or even become sick and die.