When do crayfish usually molt? Key management points during the molting period

The growth of crayfish depends on molting, and the molting rate is related to the growth stage of the crayfish and water quality environmental factors. Before each molt, the crayfish needs to accumulate considerable energy. Even so, after molting it is the period when the crayfish's body is weakest and most vulnerable to invasion by pathogens, so every molt is a life-or-death challenge for the crayfish. When do crayfish usually molt? What should be noted in management during this period?

I. When do crayfish usually molt?

Around May is the peak period for crayfish molting, and crayfish have relatively high dissolved oxygen requirements during the molting process. Molting activity accompanies the crayfish throughout its life. In the first year after hatching, it will go through 10 molts. The crayfish will continue to go through molting activity roughly once a year until it matures. A mature crayfish may molt only once every three years.

II. Reasons why crayfish have difficulty molting

1. Deterioration of water quality, shown by only half of the old shell being shed or the body actually shrinking after shedding the old shell;

2. Not being fed enough; long-term starvation affects molting, and insufficient nutrition or poor-quality feed is not easily absorbed;

3. Excessive stocking density and crowded conditions; mutual interference will prolong the molting time or result in death without being able to molt;

4. Sudden changes in water temperature; low temperatures hinder molting, and high temperatures also delay molting;

5. Drug effects: after indiscriminate use of antibiotics, using too many drugs affects molting or produces abnormal phenomena;

6. Too much light or too great water transparency, with the water clear all the way to the bottom, causing the crayfish to swim chaotically around the pond all day without molting;

7. Insufficient calcification of the carapace makes molting even harder;

8. Parasitism by ciliates and other parasites.

III. Key management points for crayfish molting

1. Preliminary work

As long as we do a good job in other steps, we can ensure the normal molting of the crayfish. What we need to do is mostly preliminary work, such as the maintenance of water quality and water bodies, the planting of aquatic grasses and aquatic plants, the disinfection of the pond, and the removal of natural enemies, and so on. Good water quality can provide the crayfish with a better growing environment, and good aquatic grass can provide the crayfish with part of its feed as well as a safe space during molting. These are all points we need to pay attention to.

2. Proper calcium supplementation

After the crayfish enter the pond, we need to pay attention to feed feeding. During the crayfish molting period, appropriately supplement calcium, and providing more feed with high calcium content such as snails in the food is enough. When feeding, be sure to make a good combination; both plant-based feed and animal-based feed should be present, and do not cause nutritional imbalance.

3. Observe the aquatic grass

During the breeding process, pay attention to the growth of the aquatic grass and the dissolved oxygen content of the water body. If the aquatic grass is not growing well, it proves that the water body is too poor and needs fertilizing, because without good aquatic grass, you cannot raise good crayfish. Crayfish do not have very high oxygen requirements, but you should also be careful not to let the water body be short of oxygen for a long time. Lack of oxygen will cause the crayfish not to molt, and may also cause the crayfish to die during molting because the molt is unsuccessful due to lack of oxygen.

4. Pay attention to the molting time of crayfish

The molting of crayfish does not occur at a fixed time. It is not that after the same batch of seedlings of the same size is put in, they will all molt together after a period of time. Rather, depending on feeding and other conditions, some molt earlier and some later, and basically there will be crayfish molting every day. So we must remember that when there are crayfish in the pond, we need to observe more and not blindly carry out operations such as disinfection or killing moss, which could cause the death of the crayfish.