According to the forecast of weather in the future in Phu Yen province, there will be hot weather and the rains in the evening can cause bad changes to the aquaculture environment, especially for brackish water shrimp farming. and lobster.
The water environment in the future will be unfavorable, so farmers should pay attention.
According to the Center for Environmental Monitoring and Aquatic Diseases of the Central Region, belonging to the Research Institute for Aquaculture III, the results of monitoring and warning of the environment in the area and producing brackish shrimp breeds, lobster and marine fish in Phu Yen, the observation time from August 22-23 shows that: Some environmental factors (vibrio, dissolved oxygen) have adverse changes for aquaculture.
Specifically, the total density of vibrio bacteria exceeded the allowed level at 3 monitoring points in Cu Mong lagoon. In particular, the density of vibrio in Vinh Hoa Bay (Cu Mong lagoon mouth) is 1.3 x 103 cfu / ml, Binh Phu Bridge (middle of the lagoon) is 2.2 x 103cfu / ml and hamlet 1, Xuan Hai commune (at the end of the lagoon) ) is 1,4x103 cfu / ml.
Dissolved oxygen (DO) content at most monitoring points tended to decrease compared to the beginning of August 2019, ranging from 4.42-5.70 mg / l. In particular, the monitoring point in village 1, Xuan Hai commune (the end of Cu Mong lagoon) has DO content of 4.42 mg / l, lower than QCVN 10-MT: 2015 / BTNMT for aquaculture area. production and conservation of aquatic animals (DO> 5.0 mg / l).
While it is forecasted that the weather in the future will be hot and the afternoon rains can cause bad changes to the aquaculture environment, especially for brackish shrimp and lobster farming. Therefore, the Center for Environmental Monitoring and Aquatic Diseases recommends that farmers should apply the following measures to proactively manage the environment and prevent disease for seafood.
Specifically, for brackish shrimp farmers, they need to get water into sedimentation tanks, disinfect and eliminate pathogenic bacteria before use, especially in water areas with total vibrio density exceeding the threshold. Maintain the pond water level at least 1.5 m to minimize the adverse environmental fluctuations caused by the heat (especially oxygen content often fluctuates greatly during the day and night, or when hot weather often leads to local hypoxia).
Increasing oxygen testing (especially at night), increasing the use of aeration machine, aeration to avoid lack of oxygen and oxygen stratification and temperature in the pond. Lime should be applied around the pond edge when there is heavy rain to minimize the sudden decrease in pH and alkalinity, shocking the shrimp environment.
In addition, farmers need to feed shrimps in the right ration, so there is no excess of food that will pollute the pond environment and well implement pond management measures. At the same time, monitor the health of farmed shrimp by observing daily response, color, intestine, hepatopancreas and feces, together with checking food sieve for timely treatment. Supplementing vitamins and minerals to feed to enhance the active resistance to disease prevention for shrimp farming.
For lobster and marine fish farming, farmers should maintain cages at the middle layer or near the surface layer to avoid local oxygen deficiency for farmed shrimp; regularly cleaning cages, leveling density sparse. Supplement of probiotics, vitamins and minerals to improve animal health in adverse weather conditions.