Technical cucumber seed production by the Institute NCNTTS | seed production technique two sam

I. Technical recruitment and maturation pat cucumber farming parents

1.1. Recruiting and keeping the parents

- Sand Sea cucumbers are selected as parents are the sea cucumbers healthy adults, no scratches, no sick. They are caugaht from the wild or selected from the grow-out ponds. The best size should be greater than 250 g.

 

- The carriage of sea cucumbers may shock parents leads to visceral waste was sea cucumber or premature out the transportation process should be very careful. The best is still an open carriage, prone to sea cucumbers in barrels of water and foam to keep the temperature stable during transport. Shipping parents with cucumber foam box should not exceed two cucumbers stacked layers.

- After selecting and transporting of farm, sea cucumbers are kept in ponds or in registered breeding conditions as follows:

+ Quality bottom: sand or sandy mud

+ Salinity: 25-35 ‰

+ Temperature: 25-31 ° C

+ PH: 6.5 to 8.5

- Raising keep cucumbers in ponds or sign is located near the beach hatcheries. Depending on the capacity of the camp is feeding area or large or small ponds. Feeding flapping in the sea or pond posted for cucumbers help parents grow in normal culture conditions at low density (<200g/m2), less competition for food. During feeding, hygiene regularly posted to the open water pond is also for a stable environment management, change water frequently to ensure normal development of sea cucumber.

1.2. Raising pat cucumbers mature parents in cement tanks

- Raising pat cucumbers mature parents in the tank is the decisive factor for the initiative in artificial reproduction. After patting raised in tanks, sea cucumbers parents will develop gonads uniform and easier to stimulate.

- Aquarium pat parents should have the following conditions:

+ Area: 15-20 m 2

+ Quality bottom: sand, thickness 10cm

+ Water level: 0.5 to 1.0 m

+ Salinity: 30-35 ‰

+ Temperature: 26-30 ° C

- First of all, choose the healthy individual, no scratches on 350 gram size clapping transferred on maturity. Pat tank is usually cement tank in the roof cool. Clean sand level in the tank 10cm thickness for parents buried their sea cucumber. Sea water is pumped directly into the tank or sand filter system.

- Stocking density 1 shrimp/m2, supplementary feeding in the form of fine food shrimp with 1 gam/m3 CP 9000. Change the water daily in the mornings to balance the water temperature in the water tank and replace, replace about 20% of the water volume. Time for the first round of sea cucumber farming pat mature parents lasted about a month.

II. Technical spawning

Due to asexual form of reproduction in addition to selecting each batch of about 30-40 parents the sand sea cucumber for a stimulating time. The spawning method is used when there is no previous farming techniques mature cucumber sand pat parents in cement tanks are often complex and have low reliability due cucumber mature unevenly wild . These methods include as heat shock stimulation, dried sea cucumber in the shade, water hose or pressure in combination with dried seaweed solution into the tank for stimulation. When using the above methods are the main cause parents and dirty eggs after spawning sea cucumbers. Therefore stimulation techniques to improve the current temperature is mainly stimulated. The stimulus steps are described as follows:

- Stimulate the tank temperature is raised above sea cucumbers in the tank parents clap from 3-5 degrees C before stimulating them into the tank. Earlier, sea cucumbers parents must be cleaned thoroughly with clean seawater, and instead locked for clean water in the tank prior to stimulation.

- Use a flat-bottomed tank, approx 1.5 - 2m3, clean sea water treated, purified through ultrafiltration bag 1μm to about 1/3 of the tank volume. Use a heat lamp or hoist to raise the temperature difference between the tank pat cucumbers parents from 3-5 degrees C. After the sea cucumbers were clean sand and dirt release in the intestines, put cucumber conducted on parents tank to stimulate spawning, sea cucumbers slight drop in the tank, aeration and light canvas cover to keep temperatures stable.

- After the sea cucumbers for parents to stimulate the tank, about two hours after stimulation, male ejaculation begins. The male usually ejaculates before children about 20-30 minutes, sometimes a few hours, it secretes a milky sperm solution for many minutes or even hours to stimulate biological children. When the female lays eggs released slowly or sometimes constant but increases or decreases in a few hours, a female can release more than one egg usually occur on mature individual large size.

- Observe, select the tank about 3-5 males better sperm quality to back down and catch some males left out to limit the amount of excess sperm. Males as well as the white stripe sperm emitted continuously but not clotted sperm. If so much sperm in dirty water tank will do, affect egg. The phenomenon of sperm on the egg would have reduced the rates of fertilization, influence the development of eggs and increased the incidence of larval deformities.

- After all the females release eggs end up catching all the parents are out, the eggs while avoiding loss of sea cucumber water filter. If the supply of eggs is so much more to reduce the concentration of water, avoid too densely cause broken eggs. The density of eggs in the tank should not exceed 10 stimulates egg / ml.

- The operations such as track and count how many female and male reproductive participating journalists is very important in the calculation for the next round of breeding, determine the time to estimate the egg release time eggs hatch.

- In the case of sea cucumber breeding parents are not, should not continue to use other methods. Transfer cucumber parents back tank myriad mature to support his wife.

- When the sea cucumber spawning is done, move them back to the pond to keep feeding sea cucumbers recovery for re-mastered, re sea cucumbers parents usually mature within 3-4 months.

III. Egg collection and filtering techniques

- The process of egg collection and filtration was conducted after parents cucumber and egg ejaculation stop for about an hour. Observations on the microscope, the eggs began to intersect.

- First, move the parents out of the tank gently stimulating to the water tank to prevent loss of eggs in other cases children continue to lay eggs. Sucking eggs from the tank gently stimulated through the sieve tubes siphong egg mesh size from 50 - 80μm set in brass or foam box. Use a clean filtered seawater inlet filter bowl to wash off the egg and sperm contamination arising during the spawning sea cucumbers.

- Keep eggs in the sieve frame suspended by mild stirring occasionally outside water grid. Use a glass or plastic ca bar to collect quantitative eggs and put them into the bucket clean aeration slightly before transferring eggs to larval rearing tanks. In addition, you can use a small bucket (10 liters) to suck eggs instead of eggs, in a similar way as the above steps but egg collection process will be faster. However, the latter having to spend a lot more work.

- Wash the egg and the egg in the bucket before moving into the larval rearing tanks. The density of no more than 100 eggs in egg bucket / ml, so do not let the egg density on the number of eggs in many cases than expected. Do not get eggs in the tank overnight stimulation by environmental stimuli water in the tank gets dirty and too high density egg eggs will be deposited bottom.

IV. Technical larvae float

4.1. Prepare tank

- Clean sea water through sedimentation and sand filtration is fed into larval rearing tanks through a bag filter 1μm. The environmental factors in the tank is maintained at a salinity of 30-35 ‰; temperature: 26-30 ° C; pH: 7.5 to 8.5.

- Swimming larvae were placed in the roof covered with tarpaulin or cover ensures temperature stability. The tank is suitable for floating larvae square shaped or rectangular volume 2 - 4m3.

4.2.Quan care of larvae

- Density of suitable larval rearing of 300-500 larvae / l, aeration 24/24h mode. During the first 4 days, from Auricularia larvae emerge, siphon the bottom and change the water daily. Then change the water 2 days / times.

- The process of aeration siphoned off by about 10 minutes before bed smoking, healthy this time the larvae are in the water column above the floor while the weak and dead larvae with dirt at the bottom of the tank, will be sucked outside. After finishing siphon, open to normal aeration.

- 30 vol% water changes every day. Use bags instead of mesh size 100μm water, change the water bag placed in frames, special floats in fixed larval tanks, pipe water changes put in place in order to avoid water pressure between the larvae when they latch onto the net. When water changes, water outlet must be started in order to ensure the supply of water is not disturbed. Inlet flow rate to moderate (<20/phut), larvae avoid being forced into the grid causing loss larvae.

4.3. Diet

- Approximately 30 - 36h after fertilization, the eggs hatch into larvae Auricularia. At this time, the larvae begin to eat unicellular algae with a density of 20,000 cells / ml and increased to 40,000 cells / ml in the following days. For unicellular algae the larvae until the larvae still Auricularia tank. Feeding from 2-3 times / day after water change.

- The results of research on nutrition for the larvae showed a survival rate of larvae highest combination fed Rhodomonas salina and Chaetoceros mulleri in equal proportion or algae Isochrysis galbana in the early days with Chaetoceros sp. and these days, who then also equal. However, if no hatchery rearing conditions many types of algae, the algae can be used during phase C. mulleri larvae float still effective. In the lack of fresh algae, synthetic food or dry algae Spirulina sp. can also be used to feed larvae but low efficiency.

- Doliolaria stage larvae often seek to move prices larvae clinging to the bottom Pentactula in a few days. Without the larval substratum Doliolaria will continue to float and not to stick to the bottom. Therefore, appropriate substratum must be prepared to see Doliolaria larvae appear.

- When conditions are right for sticking bottom, larvae Doliolaria will disappear from the water column in about 3 days. At this point, we metamorphosis through larval stages and larvae can Pentactula. Multicellular algae Chaetoceros sp. Khue and string algae suitable for feeding at this stage with a density of 2-3 times the floating larval stage.

V. Technical preparation for attachment

 - There are many ways to prepare for attachment Doliolaria when larvae first appear. The method generally used earlier as prices stick prepared by sea level in the tank for natural breeding on the price of natural food sticking or algae cultured from laboratory tank Quotes stick. However, these methods require complex preparation process and is usually accompanied by contamination, algae from environmental impurities from sea water is not purified, high cost and not active in production. To avoid contamination in the larval rearing tanks predators such as copepods, protozoa, worms ... most improved method is simple and effective preparation for attachment Nayla current price can be scanned by algae rather dry because the old method mentioned above.

- The appropriate price can be used as the substratum is the kind of PVC sheet. Cut sheets into corrugated PVC prices generally small size of 40 x 50cm, clean and dry. Phase dried algae (Spirulina sp.) To form viscous solution when mixed with water 1g/ml rate. Use a soft brush to scan the surface for attachment at 1 - 2g/m2 area for attachment. Dried and curled (open) forced them tightly with string algae scanning toward the inside.

- When the amount in the tank Doliolaria larvae reach about 2/3 of the total number of larvae, the animals began to drop clinging to the tank. After spending about 4 hours substratum after the water change completely dry to remove excess algae on the substratum plate dissolved in the tank.

- Number of animals cling to each water drop is 30 tam/m3. However, it will depend on the amount of larvae, ensuring that no more than 1 con/cm2 substratum.

VI. Seed rearing techniques

Approximately 25 - 35 days old, the larvae can reach sizes of about 2 - 5mm experiments carried out during net transfer to the same level. Jump seed from hatcheries in the national grid system during run plugged in the pond.

6.1. Selection pond

Ponds are suitable for nursery ponds located in areas easily tide tidal water exchange under natural food sources for many organic humus and suspended material, ensure the following conditions: - The quality bottom: sand or sandy mud - salinity: 25-35 ‰ - Temperature: 25-31 ° C - pH: 6.5 to 8.5

6.2. Design phase grid

Phase grid mesh size from 0.6 to 0.8 mm was designed rectangular narrow length. Phase grid size length x width x height corresponds to 1.2 x 2.0 x 1.2 m. Resolution grids submerged in water no more than 1 meter, each period is fixed by 4-6 bamboo or wood on the edge and bottom edge of the sea cucumber to the same period net beef not out.

6.3. Pond preparation and during run

Before moving to the same level, renovated pond before killing complicated plug-run period. Pond to be pumped, dried and destroy harmful (crab and fish data, residential buildings signing ...). Plug the grid period before releasing seed from 3-4 days to feed naturally during development to ensure food grid cucumber seed development.

6.4. Managed care

- Stocking density appropriate nursing from 600-800 during the early the/m2 grid. Cool mesh cover on the grid during the first week drop, then descending on the cover of next week.

- In the nursing process, change the water as much as possible, during regular grid toilet outside in soft trowel 3 days / times generated for open water, remove the cucumber out and create conditions for food natural development during the run.

- Check regularly run to start the period of predation as shrimp, crab or beef ... jump on stage like sea cucumbers cause shrinkage. Truss system layout dam to the island country in adverse weather conditions such as heavy rain reduces salinity, stratification and ponds during hot bottom grid and cause lack of oxygen.

- A seed rearing phase lasts about 30-45 days depending on the conditions of each pond. Check and san said the new national seed stage through to see their growth slow down. In the case of seed stored in high density, can add shrimp feed fine form with the CP 9000 1g/m2 amounts, but often very dirty floor.

VII. Technical seed collection and transport

7.1. Technique of small seed size 2 - 5mm

- Use a soft brush and clean sea water hose pressure to push early to condense on the tank and the tank bottom substratum. Nymphs can stick on the substratum shook hands in the water for them to leave the substratum. Prepare a small net revenue from 600 - 800μm located in Lu's blowdown tank to collect the larvae can, spray taps gently used children can go out early to collect seed Lu discharge.

 

- Place in water bath net revenues clean water to remove residue and pest if any. Quantification of the larvae before shipping out to the national stage. If the pond is located near the hatchery does not need oxygen pump packing, moving directly into the pond. In cases where the pond is located far from the hatchery, the oxygen pump using plastic bags to ensure the health of the pond just moving out. The process of transporting the early to avoid shocking to note the temperature, salinity and harshness during transport.

7.2. Technical seed collecting and transporting large

- When you reach the same level during the 2 gram weight, then proceed to transport the seed stage to the point of consumption.

- Use a little basketball or tennis, ensure seed is not leaked to collect the same. Especially during nets out of the water and use the entire basket of cucumbers collected in the same period. Selection of seed weight greater than 2 g to move into a new phase or into the tank the day before transport to the place of consumption. Smaller breeds will be transferred to the national grid in the other period.

- In the case where consumption at near, less than 2 hours of transport, the transport of seed applied by the foam box open. Clean sea water, stomach seed surface in shipping containers to reduce shock. Density as low as transport safety, allowing no more than 2,000 pieces / carton (size 40 x 60cm).

- In case of transportation of seed two hours away on the shipping method sealed plastic bags pumped with oxygen. Clean sea water into the third bag, 1 bag nilion density for size 10 x 50cm no more than 500 pieces / bag. During transportation keep a stable temperature not exceeding 30 degrees C, put the bag in the trunk fixed cucumber foam to reduce shock during transportation.

 

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