The development and upgrading of the crab industry is guaranteed

This summer, the high temperature in many parts of the country broke through the historical record, such as Ma'anshan, Anhui, Xinghua, Jiangsu and other places The temperature continued to reach more than 39 ° C, which is undoubtedly a severe test
for the hairy crabs that grow in the pond and are still in the dehulling stage.

Hot weather has an impact on production

Cheng Yongxu, a professor at Shanghai Ocean University, introduced that the 5th dehulling is the last dehulling of hairy crabs, and it is also the most critical growth link
.

Affected by the high temperature weather this year, crabs in the critical 4th and 5th dehulling stages have difficulty dehulling
.

At the same time, the high temperature makes the water in the lake evaporate quickly, resulting in hairy crabs being prone to severe hypoxia and death
.

Zhu Yandi, a crab farmer in Wuxi, Jiangsu Province, said that this year's hairy crab farming is a particularly difficult year
.

Multiple measures to combat the risks of farming

In the future, the frequency of extreme high temperature and drought weather may increase, and if the breeding is still carried out according to the previous technology and experience, the risks and losses will increase
.

Cheng Yongxu suggested that the first thing to do is to change the grass planting mode, with the early bitter grass and other composite aquatic weeds and yellow flower water hyacinth to cope with the frequent occurrence of high temperature weather, reduce the impact of high temperature on
crab shelling.

Some experienced farmers have also found some ways in practice, such as timely and scientific use of oxygenation facilities, cleaning up thick aquatic weeds to prevent crab hypoxia, and timely supplementing trace elements after the relative drop in temperature to improve crab immunity and molting rate
.

A crab breeding operator said that in order to solve this problem, it is crucial to expand the area of breeding ponds, and the water temperature of ponds with an area of more than 200 mu is easier to control
.

Industry experts believe that with the continuous increase of ecological environmental protection, many crabs that were previously cultivated in natural lakes will be transferred to inner pond breeding, and the crab industry also needs to be upgraded
to intensive and high-quality development.

Do a good job of management to ensure the quality of crabs

Zhou Xin, a researcher at the Freshwater Fisheries Research Center of the Chinese Academy of Fishery Sciences, said that at present, farmers should mainly do a good job in the management of the substrate, although the high temperature has passed, but the hot and stuffy days will still appear, the crab pond substrate is not good, easy to cause hydrogen sulfide poisoning, river crabs will appear trembling and other symptoms, in order to preserve the results, in the near future, it is necessary to strengthen the bottom, and the effect of splashing anaerobic bacteria to change the bottom is better
.

Feed feeding should also be done well
.

In terms of aquatic weeds management, when there are aquatic weeds floating on the surface of the pond recently, they should be removed in time to avoid accidents
in which rotten grass affects water quality.

(Wang Jiayi, comprehensive finishing)

China Food News(2022/09/22/08)

(Editor-in-charge: Wang Jiayi)