CN102669021B - Method for temporary culture, egg laying and egg protecting of octopus variabilis sasaki and device for method - Google Patents

Abstract

The invention discloses a method for temporarily raising, laying eggs and protecting eggs of long octopus and the device used. The method includes 1) selection of parents, 2) temporary raising of parents to promote maturation and 3) steps of protecting eggs; and A specially designed octopus nest is used. The method of the invention is simple to operate, and the device used has low cost and high utilization rate, and can effectively improve the survival rate of the long octopus parent body, the amount of eggs laid, the hatching rate of fertilized eggs and the health of the seedlings. And the octopus nest of the present invention simulates the natural nest structure of the long octopus, which is more suitable for the behaviors of concealing, resisting enemies, laying eggs, and protecting eggs for close octopuses. Moreover, the octopus nest is simple to make, easy to use, and has a high utilization rate. It is a low-investment, A long octopus nest with good effect.

Description

A kind of method and the device used for temporary raising, laying eggs and protecting eggs of long octopus

technical field

The invention belongs to the technical field of aquaculture, and in particular relates to a method for temporarily raising long octopuses, laying eggs and protecting eggs and a device used therefor. the

Background technique

Octopus minor belongs to Cephalopoda, Octopus order, Octopus family, Octopus genus, commonly known as horse octopus, giant octopus or octopus, and is widely distributed in the Bohai Sea, Yellow Sea, East China Sea, South China Sea and Japan Sea in my country. The long octopus is an annual, and its breeding peak in the north is from April to July. The long octopus is delicious and has rich nutritional value. It is exported to Japan and South Korea in large quantities. It is an important foreign exchange-earning treasure in northern my country. the

Long octopuses generally use PVC pipes or tiles as octopus nests during artificial temporary breeding and broodstock cultivation (Qian Yaosen, 2011). Both ends of the PVC pipe are open and have the same inner diameter. Many octopuses often squeeze into the same nest, causing the octopuses to fight each other and cannibalize each other, which is not conducive to temporary breeding and maturation, and is not conducive to egg protection. There is a big difference between the tile and the natural octopus nest, and no cave structure is formed. After the long octopus lays eggs, the egg group is more easily disturbed by the outside world. Based on the observation of the breeding habits and nests of long octopuses in the natural ecological environment, the octopus nests suitable for their habitat and breeding were designed, and a set of technical systems and methods were established to meet the needs of artificial seedlings, breeding and release. the

Contents of the invention

The object of the present invention is to provide a kind of long octopus temporary support, method and device used for laying eggs and egg protection, solve the problems such as mutual cannibalism of long octopus parents and mutual cannibalism during egg protection under the existing conditions, to make up for Insufficiency of existing technology. the

The method of the present invention comprises the steps of:

1) Selection of broodstock: Harvest long octopuses from natural sea areas from April to May every year, and select those with complete body surface, plump carcass, and healthy body color as the broodstock;

2) Temporary raising of the parent body to promote ripening: the parent body is temporarily raised in the temporary raising pool to promote ripening, and octopus nests are placed in the temporary raising pool. The number of octopus nests is twice that of the parent body; The salinity is 28-32‰; the light intensity of the holding pond is not more than 500Lx; the temperature is raised by 1°C every two days, and when the temperature rises to 23-26°C, it is constant, and the bait is fed every day until the brood spawns;

3) Egg protection by the parent body: after the parent body lays eggs, move the octopus nest with the parent body into the hatching pool, seal the opening end of the octopus nest with a screen, so that the parent octopus can protect the eggs in the octopus nest, and prevent the parent octopus from escaping from the octopus nest; The water temperature of the hatching tank is adjusted to be constant at 24°C, the light intensity is adjusted to not exceed 300Lx, and the water is cultivated and bait is fed. Check the condition of fertilized eggs every day, and remove bad eggs and dead eggs in time. the

For bait feeding, during the temporary maturation period of broodstock, the bait is lugworm, fiddler crab, meat ball near crab, Philippine clam, variegated clam and square clam, and chilled white shrimp, and the ratio of various baits is white Shrimp 30%, crab 30%, clam 20%, clam worm 20%, when the parent octopus is about to lay eggs, reduce the proportion of crab in the bait to 10%, and increase the ratio of clam and clam worm to 30%. During the brood protection period, continue to cast bait. The bait is crabs with chelated feet removed and clams with half of the shell removed to supplement the energy of the broods and improve the quality of the broods. the

The octopus nest used in the present invention includes two parts: a water-permeable cylinder and an egg-protecting cylinder. The water-permeable cylinder is cylindrical, with an open front end and a rear end connected to the egg-protecting cylinder; hole; the rear end of the egg protector is a closed conical shape. the

The front end of the above-mentioned permeable cylinder is equipped with a stainless steel ring for increasing the weight; the diameter of the small holes is 0.8cm, and the distance between small holes is 1.5cm. the

A pottery pendant is connected to the rear end of the above-mentioned egg protector. the

The octopus nest has a total length of 50-70 cm and a diameter of 10-15 cm. the

The present invention has the following advantages:

1. Simulate the structure of the long octopus nest under ecological conditions, and use sterile materials to prepare the octopus nest, which has the characteristics of firmness, corrosion resistance, wear resistance, and low price, which is convenient for large-scale promotion and application, and makes the long octopus reasonable distribution to ensure The broodstock are isolated from each other to create a stable environment for laying eggs and protecting eggs, avoiding external interference and cannibalism and fighting among the broodstock, which can increase the spawning rate and hatching rate of long octopuses. the

2. During the whole breeding process, the bait mix is reasonable. In the stage of temporary breeding and maturation promotion, crustaceans such as crabs account for a large proportion of the bait, which greatly promotes the gonad development and maturity of the parent octopus, improves the amount of eggs laid and the quality of fertilized eggs; during the egg protection period, the activity of the parent octopus weakens, reducing the The proportion of species, as well as providing crabs with their chelater feet removed, avoiding crabs attacking broodstock and preventing crabs from destroying fertilized eggs and broodstock. Energy for long-term egg protection. This plays a key role in improving the hatchability and survival rate of larvae. the

3. In addition, during the egg protection period, technical means such as temperature control, light control, and running water culture were adopted, all based on the data obtained from the detailed investigation and analysis of the ecological environment of the long octopus, and a set of breeding methods was established for the parent octopus and fertilized eggs. Stable and suitable ecological conditions. Timely removal of bad eggs and dead eggs also creates favorable conditions for the development of fertilized eggs. The whole set of cultivation system is easy for large-scale octopus seedling cultivation and demonstration and promotion. the

This octopus nest simulates the natural nest structure of the long octopus, which is more suitable for the concealment, enemy resistance, egg laying, egg protection and other behaviors of the parent octopus. Moreover, the octopus nest is simple to make, easy to use, and has high utilization rate. It is a kind of low investment and good effect. Long octopus nest. the

Description of drawings

Fig. 1: is the schematic diagram of octopus nest structure of the present invention;

Fig. 2: is the exploded view of octopus nest of the present invention;

Among them: 1. Water-permeable cylinder 2. Egg protection cylinder 3. Small hole 4. Stainless steel ring 5. Pottery pendant. the

Detailed ways

The specific steps of the method for the long octopus parent body of the present invention to temporarily raise, lay eggs and protect eggs are as follows:

1) Selection of parent body: select long octopus with complete carcass surface, plump carcass, and healthy body color as parent; prepare octopus nest at the same time: octopus nest is made of aseptic plastic, consisting of two sections, the front section is cylindrical. Permeable tube 1, rear section is the egg protection tube 2 of conical structure, total length 50～70cm, and diameter is 10～15cm. The front end of the permeable tube 1 is open, and a stainless steel ring 4 is inlaid on the tube wall; the back section of the egg protection tube 2 is gradually narrowed, and the end is closed, and the end is bound with a pottery pendant 5, which weighs 100-200g. The tube wall at the first two-thirds of the opening end of the hollow cylindrical structure of the permeable tube 1 has small holes 3, the diameter of which is 0.8 cm, and the distance between the small holes 3 is 1.5 cm.

2) Temporary raising of the parent body to promote ripening: Put the parent body in the temporary raising pond for temporary raising to promote ripening. The water temperature is 14-16°C and the salinity is 28-32‰, and the octopus designed by this patent is put into the temporary raising pond The number of nests is twice that of the broodstock. Put the octopus broodstock in. The temperature of the holding pool is raised by 1°C every two days, and then kept at a constant temperature after the temperature rises to 23-26°C. The holding workshop is shaded with black cloth, and the light intensity is adjusted to no more than 500Lx. During the temporary breeding period, feed clam worms, fiddler crabs, meat ball close crabs, Philippine clams, variegated clams, four-cornered clams, and chilled white shrimps every day at 17:00. 10%, octopus likes to eat shrimp and crabs most, and the proportion of various baits is white shrimp 30%, crab 30%, clams 20%, and clam worm 20%. Clean up the residual bait the next morning, and change 1/2 of the water every 2 days during the temporary breeding period. When the octopus parent is about to lay eggs, its vitality weakens. At this time, the proportion of crabs in the bait should be reduced to 10% to prevent crabs from attacking the parent, and the proportion of clams and clams should be increased to 30%. By adjusting the bait, it is possible to ensure that the broodstock can have sufficient live bait during the temporary maturation promotion period, and will not consume extra energy when eating, so as to promote the better development of the gonads of the broodstock and increase the amount of eggs laid. the

3) Egg protection by the parent body: When the parent body is found to be laying eggs, immediately seal the opening of the octopus nest with a rubber band and a screen, and transfer it to the hatching tank to isolate the parent octopus from each other and prevent them from escaping. During the egg protection period, the resistance of parent octopuses is weakened. Frequent changes in the environment should be avoided. The water temperature of the hatching pool should be kept at 24°C, and the light intensity should be adjusted to below 300Lx. Long running water should be used for cultivation to inhibit the growth of bacteria and other harmful organisms. And prevent the stimulation to the parent octopus when changing the water, improve the quality of egg protection. During the egg protection period, the parent octopus seldom takes the initiative to feed. Feed once every 2 to 3 days to maintain the physical fitness of the parent. When casting bait, remove the net that seals the octopus nest, cut off the claws of the fiddler crab or the crab near the meat ball, and throw it into the octopus nest, or remove half of the shell of the Philippine clam and four-horned clam and put it into the octopus nest. Feed one in the octopus nest, then seal the octopus nest with a net, put it back into the hatching pond, and clean up the residual bait the next day. During the period of pro-octopus egg protection, check the fertilized eggs every day, and remove the swollen bad eggs and dead eggs in time. With the egg protection device and method for long octopuses, the hatching rate can reach 90%, which is higher than the hatching rate of the general method. the

The structure of the octopus nest in the present invention is designed according to the nests of long octopuses in nature, simulating the natural spawning environment, effectively protecting the parents, preventing fights and cannibalism between the parents, not only improving the survival rate of the parent octopus, but also improving the survival rate of the parent octopus. The number of eggs laid, the hatching rate of fertilized eggs and the quality of larvae. During the egg protection period, the parent octopus is less active and the immunity is lowered. The method of actively feeding the octopus nest is adopted to make the parent body replenish energy through feeding. The parent octopus is protected by reducing the light intensity, keeping the temperature constant, and running water culture to improve the protection. egg quality. the

Claims (6)

1. a kind of long octopus temporarily raises, lays eggs and protects the method for ovum, is characterized in that, comprises the steps: 1) Selection of broodstock: Harvest long octopuses from natural sea areas from April to May every year, and select those with complete body surface, plump carcass, and healthy body color as the broodstock; 2) Temporary raising of broodstock to promote maturation: temporarily raise the broodstock in the temporary holding pond to promote ripening, and put octopus nests in the temporary holding pond. The number of octopus nests is twice that of the parental body; the initial water temperature of the temporary holding pond is 14-16°C , keep the salinity at 28-32‰; shade the temporary breeding pond, adjust the light intensity to no more than 500Lx, raise the temperature by 1°C every two days, and keep it constant when the temperature rises to 23-26°C, and feed the bait every day until the broodstock is about to lay eggs; 3) Egg protection by the parent body: after the parent body lays eggs, move the octopus nest with the parent body into the hatching tank, seal the opening of the octopus nest with a screen, so that the parent octopus can protect the eggs in the octopus nest, and prevent the parent octopus from escaping from the octopus nest; Adjust the water temperature of the hatching pond to a constant 24°C, adjust the light intensity to no more than 300Lx, and use running water to cultivate and feed the bait; In the step 2) during the temporary raising of the parent body to promote ripening, the bait to be fed is lugworm, fiddler crab, meat ball near crab, Philippine clam, variegated clam and four-cornered clam and chilled white shrimp, among which the various bait The ratio is 30% white shrimp, 30% crabs, 20% clams, and 20% clams. When the parent octopus is about to lay eggs, reduce the proportion of crabs in the bait to 10%, and the ratio of clams and clams to 10%. respectively increased to 30%; In the step 3) during the brood protection period, the bait is to feed crabs with chelated legs removed and clams with half of their shells removed. 2. The method according to claim 1, characterized in that said step 2) the octopus nest used during the period of fostering and promoting maturation of the parent body includes two parts: a water-permeable cylinder (1) and an egg-protecting cylinder (2). The water-permeable cylinder (1) is cylindrical, with an open front end and a rear end connected to the egg-protecting cylinder (2); and a small hole (3) is opened on the body of the water-permeable cylinder (1); the egg-protecting cylinder (2) The rear end is a closed conical shape. 3. The method according to claim 2, characterized in that a stainless steel ring (4) for increasing weight is installed at the front end of the permeable cylinder (1). 4. The method according to claim 2, characterized in that the diameter of the small holes (3) is 0.8 cm, and the distance between the small holes (3) is 1.5 cm. 5. The method according to claim 2, characterized in that a pottery pendant (5) is connected to the rear end of the egg protector (2). 6 . The method according to claim 1 , characterized in that the octopus nest used in the step 2) during the temporary raising of the parent body to promote maturation has a total length of 50-70 cm and a diameter of 10-15 cm.

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