High quality fish

Lach Lau is a freshwater fish that grows and develops well in both freshwater and brackish water environments, is common in most canals, and prefers to live in locations with fast-moving water and high levels of dissolved oxygen. Initially, the main food of the grasshopper is worms, larvae, insects and crustaceans. When grown, they eat adult insects, shrimp, shrimp, and small fish. In the natural environment, the locust can reach a size of 150-250 g/head after 1 year of age, after 2 years the weight has more than doubled, which corresponds to 450-500 g/individual.

In fact, the chrysanthemum has been researched for successful artificial reproduction and actively contributes to a source of high-quality seeds to enable the commercial cultivation process. However, only a few facilities in the south can supply this item, the basic supply is not enough to move the goods, resulting in a “high price” situation of traders, causing many difficulties for households who have genuine agricultural needs to access on high-quality seed sources.

In general, however, the model of commercial locust breeding is still a promising new direction. After long study and careful evaluation of factors, it was found that Lach Lau can grow and develop well with local ecological conditions, as well as meet people’s technical level and investment conditions, Nghe An Aquaculture Breeding Center decided the topic “Application of scientific and technological advances to experiment with commercial farming of Scads in industrial scale soil ponds”.

The meat is delicious, has a very high economic value, fish with a size of 300 – 500 g/fish is sold for 250,000 – 400,000 VND/kg, this creates impetus to accelerate the exploitation of natural and individual fish stocks Fishing methods (electricity, chemicals, etc.) have led to a sharp decline in the production of natural fish, so shifting to industrial agriculture is the right direction to follow the trend.

New potential breeder

Nghe An is a province with relatively harsh climatic conditions, summer is too hot, winter is too cold, with completely new agricultural issues such as Lach Lach, it is a relatively difficult “test”.

Another difficulty is that there is no way to supply chameleon seeds in the area, so the seed source has to be ordered in Hau Giang province and then transported by air at a density of 500 seeds/barrel, which is quite expensive. In turn, juvenile fish are selected from a reputable supplier, so the quality is guaranteed, healthy, the degree of loss is negligible, and the survival rate after transportation reaches 99.8%.

To avoid fish shock in a new environment, experts recommend that farmers must actively regulate the water source and keep a perfect balance by installing a water island system that provides more dissolved oxygen, installing a roof, releasing heat. resistant water hyacinth, etc. Stocking should be done in the early morning or late afternoon. Before stocking, the fish must be bathed with diluted salt water with a concentration of 2-3% within 15 minutes to prevent infection and disease.

Raising locusts is quite troublesome, but not difficult. Depending on the level of farming, the breeding method has an appropriate stocking plan to ensure the highest efficiency. In large-scale earth ponds in particular, the appropriate stocking density is 5 to 10 fish/m2. The healthy young fish with a size of 12-15 cm are considered the most suitable, the larger the young fish, the lower the loss rate.

The model in Nghe An was officially seeded on April 16, 2021 with a number of 9,000 animals, the seed size is 8 to 10 cm/individual, the stocking density is 6 fish/m2. At the time of hatching, the size of the grasshopper is small, the mouth is small, so the rearing process uses very small pellets, 2-3mm in size. For the first 2 months, the team actively mixed and added earthworms to create scent carriers, increasing the ability to catch bait for the locusts.

During the farming season, the local weather often shows unusual fluctuations, the temperature changes suddenly, causing many troubles. To cope with the intense sunlight and high water temperature during the summer months, the team actively used water fans to neutralize and avoid oxygen starvation. In winter, the water temperature fluctuates between 23 – 38 degrees Celsius, thanks to the initiative in the air conditioner it should keep the appropriate threshold.

During the experimental breeding process, it was shown that the carp has high vitality, but is very sensitive to environmental and weather changes. Therefore, it is necessary to be good at general disease prevention by feeding in a timely and appropriate manner and using foods with guaranteed protein content that do not mold. Farmers need to manage feed effectively to avoid excess, shortage, detriment to fish growth and disturbance of the pond environment.

At first there was not much practical experience, but raised in the context of hot summer, so there was a time when the scales suffered from heat shock, lost their viscosity, and some died. Given the above situation, the group used potassium permanganate at a dose of 3 ppm in combination with EM probiotics evenly distributed throughout the pond. After only 2 weeks, the infected fish were healthy again, catching good baits, and the loss rate was low and not significant. Thanks to good epidemic prevention, the disease of Scads is basically well fought.

Master Truong Van Toan, Head of Technical Planning Department (Nghe An Aquaculture Breeding Center) evaluated: The sea bass maintains a fast and stable growth rate, with a low loss rate, proving that the fish is well adapted to the ecological conditions in Nghe An. The larger the stalagmite, the higher the value, which is preferred by traders, so it’s not advisable to rush to harvest unless the weight and size are guaranteed.

The economics of raising chameleons are the same as raising eels, the raising process is not too complicated, the biggest hurdle at present is that Nghe An has not been able to proactively procure seeds, so there are also additional production costs. Actual results indicate that chrysanthemums are an appropriate and long-term cultural object to be replicated in Nghe An Province.

In order for the commercial breeding of scad fish toward commodities to flourish and bring outstanding economic value, the Ministry of Agriculture and Rural Development and Nghe An Agricultural Advisory Center must continue to arrange and build new breeding models, at the same time promote propaganda, education and technology transfer, so that can approach the majority of agricultural themes, capture the process of progressing replication, and stimulate the general market.

The net is pulled every 30 days to check and evaluate the development of the fish. After 9 months, it was found that the survival rate of locusts in Nghe An reached about 61%, the average harvest amount was 220 g/fish/kg, the harvested production was 1,208 kg of commercial products, and the yield was 16 tons/kg, ha/plant , feed conversion ratio FCR = 2.73, these parameters essentially met the objective of the topic.