What to do when grass carp lose their appetite? Causes and control methods

Grass carp is one of the main species in freshwater fish farming in China, but anorexia can occur when farming grass carp. The feeding condition of grass carp is directly related to the economic returns of farmers, so this is a rather serious problem. So what causes anorexia in grass carp? How should it be solved? Let's take a look.

1. Symptoms of anorexia

At the beginning of feeding, grass carp eat fairly normally, but after a period of time their feed intake will be found to drop noticeably, and sometimes they may suddenly stop eating altogether. The shoal gathers and swims at the surface of the water, and some swim around holding feed or forage in their mouths, but rarely actually ingest it.

2. Causes of anorexia

There are many causes of anorexia in grass carp. For example, sudden weather changes: in early spring the temperature difference between day and night is large, causing frequent convection between the upper and lower water layers, and the water temperature of the upper and lower layers differs greatly, which triggers anorexia. Early spring is also a period when parasites break out, and a large number of parasites parasitize inside the grass carp, causing anorexia. There is also deterioration of the rearing environment: poor water quality and bottom quality, more toxic substances in the water body, and higher oxygen content, which affect the normal feeding of grass carp. There is also the problem of insecticides or feed: when killing parasites, insecticides may be splashed, which may cause poisoning in grass carp and thus affect the amount eaten. In addition, feed that has deteriorated or gone moldy will also affect the amount eaten.

3. Preventive measures

Water quality and bottom quality must be handled well. Before farming, use quicklime or bleaching powder to thoroughly clear the pond, then expose the pond bottom to sunlight, which can reduce harmful substances in the bottom. Attention must be paid to water quality management, and the water should be changed frequently. From early spring to around Qingming, Beichongjing and abamectin can be used to kill parasites, generally used twice a week, with good results; pay attention to the concentration so as not to cause poisoning in grass carp. The feed and forage fed must be fresh, and uneaten feed should be removed promptly so as not to pollute the water quality.

4. Treatment

For anorexia caused by parasites, Chongjunxiao combined with copper sulfate can be used to kill them, and on the second day Shuanshui Jieduji can be used to detoxify, which can improve water quality. For anorexia caused by poor bottom quality and water quality, Diduxiao can be splashed over the whole pond to decompose organic waste, and on the second day Yingji Jieduling can be used to detoxify.

The above is an introduction to the causes of anorexia in grass carp and the control methods. We hope it helps you. To learn more related knowledge, please follow us.