What are the key technical points for abalone farming

There are many methods for growing out abalone: bottom-sowing culture (also called natural enhancement), raft cage culture, as well as industrial farming and tunnel farming, and so on. Regardless of which farming method is used, choosing clean water quality is especially important.

Natural seawater farming conditions

(1) Seaweed reproduction and abundant feed.

(2) Sea areas with clear, flowing water and stable seawater specific gravity, maintained above 1.020 throughout the year.

(3) The bottom substrate is rock reef and stones.

(4) Sea areas with no industrial pollution, few predators and pests, and preferably no freezing in winter and no drift ice in spring.

Seedling transport

Abalone transport uses two methods: dry transport and wet transport. Generally, dry transport is used for short distances and short durations, while wet transport is used for long distances and long durations. Transport usually uses plastic sheets as the attachment substrate for abalone, placed in washed and disinfected hard containers. Abalone to be transported must be selected and held in temporary culture to increase transport survival rate. Abalone transport plans and arrangements must be thorough. In the dry transport method, abalone density must be reasonable, without squeezing each other, ensuring high humidity and low temperature, with regular water sprinkling, preventing direct sunlight and rain, placed in a ventilated and shady place, and transported to the destination on schedule. In the wet transport method, the pump must be guaranteed to operate normally, with sufficient seawater, low density, no overlapping, large water flow, and small temperature difference, and feces and debris must be removed promptly. If transport time is too long, a small amount of feed should be given.

After transport, once abalone reach the destination, they must undergo a period of temporary culture to restore their vitality before being detached for separate rearing. For injured abalone, methods such as lowering water temperature, ultraviolet sterilization, or medication can be used.

Farming methods

(1) Seabed farming: Place juvenile abalone about 2 cm in size into farming cages, with 10-30% feed enclosed, seal them well and place them on the seabed; juvenile abalone can also be placed directly into sea areas with better natural conditions (enhancement).

(2) Raft culture: Place juvenile abalone into abalone farming cages, then fix them on floating rafts for farming, feeding on schedule, removing feces, debris, and residual feed, scrubbing off mud, and ensuring water flow.

(3) Pond farming: In areas with the necessary conditions, ponds can be built on land, using flowing water and aeration for farming.

(4) Industrial farming: Build abalone farming rooms, and control water temperature by constructing cooling and heating systems; this is one farming method.

(5) Tunnel farming: Using the natural condition of the tunnel's own constant temperature, and through treating water quality, this adopts intensive farming (it can be called a type of industrial farming.

Feed Juvenile abalone being farmed must be fed, and the quality of the feed directly affects the growth rate of abalone. Generally, abalone about 3 mm in size still cannot feed on large seaweeds and mainly rely on attached diatoms as food, so no feeding is needed at this time; after growing to 5-6 mm, they begin to also eat tender seaweeds such as Enteromorpha. As individuals grow, they shift to mainly feeding on large seaweeds.

In natural sea areas and farming, the frequency and amount of feeding depend on the season. In summer, water temperature is high, seaweeds rot easily, and the thalli decay and sink to the bottom; ammonia nitrogen in the water increases and dissolved oxygen decreases, easily causing deterioration of the culture environment and affecting normal activity of abalone. Therefore, at this time feed once every 2-3 days, and the amount fed should be smaller, just enough to be eaten completely. Autumn is the season when abalone grow relatively fast, so sufficient fresh feed needs to be supplied, feeding once every 4-5 days. In winter, water temperature is low and abalone eat little; fresh seaweed soaked in water for 7-8 days will not rot, so in winter feeding once every 8-10 days is sufficient. Note that each feeding should be carried out after removing feed residue and abalone excrement and replacing with fresh seawater.

Abalone prefer tender seaweeds. When fresh seaweeds are unavailable, dried algae can be soaked and used as feed, and mixed algae feeding gives better results. Among seaweeds, wakame, Codium fragile, kelp, and Sargassum are seaweeds that abalone relatively prefer to eat, with good feed results and fast growth. For laver, which is relatively abundant in local resources, test results show it is not ideal and has a great impact on abalone digestion.

Abalone farming can also feed artificial compound feed. When using it, consideration should be given to the fact that it contains animal protein and rots easily when soaked in water, so the feeding time should be correspondingly shortened.