How to cultivate abalone to get high yield? Choosing good seedlings is the key.

Abalone is listed as the first of the eight treasures, its taste is delicious, delicate and delicious, rich in nutrition, dry product analysis, containing 40% protein, 33.7% liver sugar, 0.9% fat, and vitamins and other trace elements, abalone meat in addition to fresh food, it can also be made into collection of dried products and all kinds of canned food. Abalone has high economic value, and many farmers are interested in it, so how to cultivate abalone to achieve high yield? Choosing a good seedling is the key.

I. selection of abalone fry

First of all, observe the growth mark of abalone fry and whether the shell color is obvious, and select the seedlings with obvious shell color. Seedling specifications should be uniform, generally with a length of 2 cm, to ensure that there is no obvious gap at the edge of the shell. This kind of abalone fry has strong vitality and exuberant vitality, so it is suitable for artificial breeding; secondly, observe the adsorption capacity of abalone fry, flip the abalone fry and observe its overturning time to judge whether abalone fry is vigorous or not; finally, abalone fry should be purchased in the best period of abalone fry growth, and abalone fry purchased need to be fully sterilized before they can go into the sea.

II. Artificial culture environment

Abalone culture should choose the sea area with smooth water depth, fresh and pollution-free water quality, no nearby rivers, rich seaweed resources, stable sea water salinity and medium salinity. The sea water should not be too shallow, and the best water depth should be between 15 and 20 meters. The range of living water temperature of abalone is 1 ℃ ~ 28 ℃, and the optimum water temperature for growth is 14 ℃ ~ 22 ℃. Abalone belongs to medium salinity marine life, which requires that the sea water salinity should be stable at 29 ‰ ~ 31 ‰, the lowest is not less than 27 ‰ and the highest is not more than 36 ‰. Abalone likes smooth flow, so you should choose a regular round trip to and from the sea, with a flow rate of 50 to 60 meters per minute. The pH value of abalone is between 8 and 8.4, dissolved oxygen is not less than 4 mg per liter, ammonia nitrogen is not more than 100 mg, and organic oxygen consumption is less than 0.5 mg.

The specification of the new abalone cage is 52 × 52 cm, with fillet four-layer combined square plate cage, each layer can store 150 abalone with shell length of more than 3 cm, one cage with 4 layers and 600 abalone; specification 40 cm 8-layer modified cage, each layer can store 80 abalone fry with shell length of more than 3 cm, and 640 abalone fry with 8-layer modified cage. Japanese zipper multi-layer cage specification 60cm, each layer can release shell length of more than 3cm abalone fry 200, a cage 5 layers can release abalone fry 1000. Taking spring fry as an example, abalone will grow to 4.5 centimeters by mid-April next year, and it is necessary to measure and sparse the seedlings in time. The new abalone cage is 150 per layer, which can be sparse to 80 per layer; the modified cage is 80 per layer, which can be sparse to 50; and the Japanese zipper multi-layer cage is 200 per layer, which can be sparse to 120 per layer.

III. Feeding management

For abalone seedlings that have just been put into the culture sea area, they are mainly seaweed, and according to the actual feeding demand, abalone seedlings can be fed with bait such as Ulva Lactuca. At the same time, it is also necessary to mix artificial bait. In the three seasons from September to November, seaweed bait is generally scarce, which is mainly artificial bait. At the same time, the dried kelp can be fully soaked and crushed and then fed to abalone. In the process of feeding, if seaweed is the main feed, then the amount of feed should be appropriately increased to ensure that abalone has sufficient food to eat. In general, abalone seedlings are fed every 4 to 6 days, and the feeding should be based on the proportion of 90% 120% of the total amount of abalone, and the residual bait should be controlled between 15% and 20%. In the process of abalone feeding and management, whether the feeding is scientific or not and whether the feeding amount is sufficient is the key factor to determine the growth rate and survival rate of abalone. Years of practical experience shows that ensuring the freshness of the bait is of great help to promote the healthy growth of abalone. Fresh bait can ensure the feeding quality of abalone, so as to better improve the disease resistance of abalone and improve the survival quality of seedlings. In the specific feeding process, the feeding amount of bait should be adjusted scientifically according to the individual size of abalone and sea water temperature.

IV. Daily management

In daily management, cage racks, wooden bars, root ropes, hanging ropes, floats and falling stones should be inspected frequently. If the phenomenon of rope entanglement is found, it should be solved in time, especially before the typhoon comes, it is necessary to check in detail whether various abalone culture facilities are firm. Remove shellfish and algae mud from the cage wall or cage at any time, especially oysters, mussels, barnacles, sea squirts, bryozoans and sea anemones fixed on abalone shells. Most of these enemy organisms can be fixed on the net cage and abalone shell, resulting in the decrease of water permeability of abalone cage, affecting the action and growth of abalone, making it difficult to eat, thin and dead. At present, prevention and manual removal are mainly adopted for these enemy organisms. Prevention is to avoid the peak period of their attachment on the basis of mastering the law of reproduction, and it can also be prevented by pharmaceutical coatings. Manual removal is to use rubber rods to gently beat the algae and shellfish on the abalone cage, the rubber rods do not damage the net cage, and the remaining unbreakable shellfish fixed on the abalone shell are cleared with a small shovel. In addition, the floating mud in the cage should be cleaned every time after going out to sea to prevent death caused by mud blockage.

The bait is particularly important when raising abalone seedlings, and it must be prepared in advance. Before the larvae are collected, the collector should be pre-attached with benthic diatoms or soaked in a flat and thin culture pool for several days. Then these collectors with adherent diatoms and unicellular diatoms were transferred to the larval culture pool to collect the larvae at the later stage of the surface plate. In the process of raising seedlings, algae culture should be continuously strengthened, in addition to adding appropriate amount of nutrition to the larval culture pool, and strengthening the light at the same time, so as to promote the reproduction rate of benthic diatoms and maintain a balance between the reproduction number of benthic diatoms and the food intake of larvae or juvenile abalone. Therefore, fertilizers need to be added constantly. If the basic food is insufficient, the feed plate should be supplemented or replaced after changing water to meet the feed intake of larvae. Abalone bait is mainly kelp, undaria and Ulva Lactuca, followed by sargassum, sargassum, brown algae or red algae. Abalone raised in shallow water can eat dozens of grams of small kelp every day. The food intake of abalone varies with the season and generally eats more in the season with higher water temperature. When feeding, we should first remove the residual bait and wash the floating mud and attachments in the abalone cage, so as to create a good environment for the growth of abalone. The feeding amount depends on the feeding condition of abalone, generally according to the weight of abalone 15%-20%. The feeding times are once every 8 days from March to April, once every 5 days from April to June, once every 7 days from June to July, once every 10 days from July to September, once every 7 days from September to December, and once every 15 days from December to March.

V. Disease prevention

Because abalone is cultured on the sea surface, the drug control is difficult and the cost is high, so it is mainly based on prevention in the breeding process, by maintaining a good water quality environment, feeding fresh bait, and regularly checking the growth of abalone. Found that sick abalone timely isolation, through the use of comprehensive prevention and control measures to improve abalone physical resistance to ensure the economic benefits of farmers.