Technical Guidance intensive brackish water shrimp farming, semi-intensive disease restrictions

Update: 25-09-2015 11:09:34 + GMT7

 

I. CONDITIONS APPLY

- Base brackish water shrimp farming must lie in planning areas of intensive shrimp farming, semi-intensive local.
- The livestock must have ditch level, separate drainage ditches ensure adequate supply of clean water for farming needs.
- Each facility must feed accounts for 15-20% deposit reservoir surface area for drinking water treatment and removal of impurities before it enters the pond; Devices equipped environment: pH, oxygen, NH3, NO3, salinity, ..

II. TECHNICAL GUIDELINES:

2.1. Preparing the pond:

2.1.1. Pond, settling pond:

- Step 1: Remove the shallow ponds and settling ponds. Removing predators in the pond from the previous crop (shrimp, crabs, snails, insects, trash fish). Dredge pond and repair the shore, the water drain and drainage. San bottom slope toward the drains. Must carefully stamped lined pond or tarpaulin to prevent erosion and limit leakage. Mesh fence around the pond to avoid intermediate host species from external pathogens such as crab, cuffs, solid.

- Step 2: Sprinkle lime (lime kilns) dosage of 20-30 kg / 1,000m2 (pH> 4) or 30-40 kg / 1000m2 (soil pH ≤4) are bottom of the pond.

- Step 3: Towed thoroughly soaked into the bottom lime to kill all the shrimp, crab, cuffs, snails, insects, trash fish remains, sterilized in mud, detoxification (heavy metals, H2S) and neutral pH. Pond liner bottom canvas just cleaned and disinfected.

- Step 4: Dry the pond bottom about 5-7 days.

For those not exposed ponds are: shallow water pumps, used rakes tailings pond at the end corner, pumping waste into the sewage pond, then proceed liming with doses as step 2.

Note: After each crop, have dried hard substrata settling ponds, ponds for 1-2 months to stop the service, destroy pathogens, mineralization and environmental restoration substrata.

 

2.1.2. Water treatment and water taken into the pond

- Step 1: Get the water to settling ponds through thick cloth filter bag to remove rubbish, larvae, shrimp, crab, cuffs, snails, insects, trash fish. Let stand for 3-4 days.
- Step 2: Run paddle continuously for 2-3 days to stimulate egg shrimp, snails, insects, trash fish hatch into larvae.
- Step 3: Removal magazine, sterilized water in settling ponds in the morning (8 am) or afternoon (16h) with chlorine concentrations of 30 ppm (30kg / 1.000m3 water), or the complex insecticide named in list allowed to circulate in Vietnam (no plant protection drugs and prohibited substances).
- Step 4: Fans of water continuously for 10 days to decompose residual chlorine. Check residual chlorine in water with a reagent.
- Step 5: Supply of water from settling ponds across the pond (through multiple layers of thick fabric filter bags) until the water level in the pond reaches from 1.3-1.5 m. Let stand for 2 days.

Note:

- Do not kill impurities in the pond.

- Do not get water to settling ponds as: i) foreign channel / trench have much scum, mucous membranes, much silt; ii) water in epidemic areas; iii) water phenomenon glowing at night.

 

2.1.3. Water coloring:

Causing watercolor help develop micro-plankton, stable water environment, create favorable environment shrimp shocked limit, increase the survival rate.

Two days after the water into the pond, causing watercolor by:

Option 1: by bran incubated (ingredients: rice bran, soybean meal, fish meal mixed at the ratio of 2: 2: 1. Cook, incubated for 2-3 days).
- Step 1: At 7-8h Brightness: black Dolomite lime CaMg (CO3) 2 or agricultural lime CaCO3 dosage 100-150 kg / 1000 m3.
- Step 2: At 10-12h Lunch: bran brewed fertilizer dosage 3-4 kg / 1000m3.
Repeat step 2 above continuously for 3-5 days until the level of water reaches 30-40 cm.

 

Method 2: using molasses + bran + soybean meal (ratio 3: 1: 3) incubated for 12 hours.
- At 9-10 am: Fertilizer molasses + bran + already brewed soy flour dosage of 2-3 kg / 1.000m3 pond, continuous 3-day attacks.
- When the water in the pond color turns of algae Khue (yellow or brown), or green bean shells, proceed stocking.
For hard pond water coloring, watercolor or unstable should additional mineral components, silicon to keep the pond water color.
May cause watercolor by biological products under the guidance of reputable manufacturers to decompose organic humus suspended, identify dead algae buildup by chemical disinfectants used before, creating beneficial bacteria source Help stable culture environment, enabling shrimp grow well right from the start.

 

Note:
- Do not use inorganic fertilizers cause water color.
- Do not kill impurities in the tank when the water removed.
- Check and adjust the environmental factors in Pond ensure appropriate thresholds before stocking:

 

Environmental factors shrimp pond water optimal limit for optimal prawn limit for white shrimp
Concentration of dissolved oxygen (DO)> 4 mg / l> 6 mg / l
pH 7.5 to 8.5 (ranging in date not exceeding 0.5) 7.5 to 8.5 (ranging in date not exceeding 0.5)
5-25 ‰ salinity 15-25 ‰
Alkalinity 80 -120 mg / l 120-150 mg / l
Degrees in 30-40 cm 30-40 cm
NH3 <0.1 mg / l <0.1 mg / l
H2S <0.01 mg / l <0.01 mg / l
 
 
2.2. Paddle and paddle runtime

System layout and paddle fan runtime must generate oxygen demand for farmed shrimp, particularly the time evening / night / early morning when dissolved oxygen levels decrease / low of the day.
Need to increase runtime fan or fan system layout add shrimp, especially in the hot sun or rain time lasts.

 

2.2.1. Placement propeller:

- The banks of 1.5 m.
- The distance between two ways paddle 60-80 cm, fitted staggered.
- Depending on the shape of the pond where water wings arranged to create optimum flow and provide enough oxygen demand for farmed shrimp.

2.2.2. Number of country fans:
- For tiger prawns:

Pond area (m2) Density: 15-20 children Density: 20-25 the rotation speed (revolutions / minute)
2000 20-25 25-30 wing wings 100-120
5000 50-60 wing 60-80 Wing 100-120
   
- For white shrimp: white shrimp requires huge oxygen. Therefore, depending on stocking density can design the water system by the propeller fan of plastic or plastic combined rotor and rotor blades quills or other oxygen supply to provide oxygen to the pond. Rev up the plastic blades of> 120 cycles / min.

 

Pond area (m2) Density (fish / m2) Number of Number of staging platforms sailed quills fan
2000-3000 30-60 4 unit (10 blades / frame) 1

60-100 4 frame (10 blades / unit) 2
4000-5000 30-60 6 unit (10 blades / unit) 2

60-100 6 unit (10 blades / frame) 3-4

2.3. Choose and stocking:

2.3.1. Breeding:

- Select seed purchased from reputable institutions, have tested negative patterns on pathogens MBV, white spotted, yellow head, Taura, IMNV, pancreatic necrosis liver ...
- Usually varieties: tiger prawns P15 - P20, P12 vannamei older.
- Check the seed health by shocking:
+ Shock salinity: Get 40-50 crawfish varieties in 300 ml beaker containing water from the same transport bag. Lower salinity suddenly down to 15 ‰ and track for 30 minutes, if the survival rate of 100% is satisfactory.
+ Shock with formaldehyde: Drop 40-50 seed in the cup, glass cup containing formalin concentration of 100 ppm and monitored for 30 minutes, if the survival rate of 100% is satisfactory.

 

2.3.2. Stocking:

- Stocking density:
+ Prawn: Intensive 15-20 / m2; 8-14 semi-intensive culture / m2.
+ White shrimp: 30 - 60 birds / m2 (for those new convert) and 60-80 / m2 (those with experience and qualification).
- How to drop:
+ Drop in the early morning or evening.
+ Before stocking should run from 8-12 hour paddle to ensure the dissolved oxygen in the pond must be greater than 4 mg / l.
+ Balance between how similar water temperature and water by floating pond seed packages on the lake a few minutes. Then the water slowly filled the bag, hold the bottom cover from the upside to seed under the pond water.

2.4. Care and management:

2.4.1. Feeding:

Feeding under the guidelines. Also, depending on the actual (health shrimp molting cycle, weather, ...) and track ready to eat / fishing while shrimp and older from 20 days to adjust, manage food accordingly, avoid feeding deficiency or excess food will affect the growth and health of the shrimp.
Fed 3 times a day.

 

2.4.2. The amount of food

- Month first animal: Use a small food drop for the new period.

+ On the 10th after stocking, for some food in clinical / nhá / hooves to get acquainted shrimp, easy to check the amount of leftovers later. Feeding tray placed in flat, 1.5- 2 m from the pond, behind the propeller 12 - 15m, not placed in the corner of the pond, around 1600-2000 m 2 set 1 screen.
+ After 15 days can use supplements provide vitamins, minerals, as directed by the supplier to help promote health shrimp.
+ Prawn: First day for 1.2 to 1.5 kg / 100,000 seeds every two days rose 0.2-0.3 kg / 100,000 seeds.
+ White shrimp: First day for 2.8 to 3 kg / 100,000 seeds. In the first 10 days, just 1 day up 0.4 kg / 100,000 seeds. From day 10-20, just one day increased by 0.5 kg / 100,000 seeds.

- Month Monday farming harvest:

+ Adjust food in recent days to monitor the volume on prepared food leftovers.
+ Converting food matched the development stage, size shrimp oral and nutritional needs as the manufacturer's instructions on the package. When feed conversion, so mixing two old and new foods to eat at least 3 days.

How to adjust the amount of food:

Check food in clinical / nhá What to eat for the next time
If shrimp eats 5% Increase food for later
If food residue about 10% Keep the food for later
If leftovers of about 11-25% food 10% discount for later
If leftovers of about 26-50% food 30% discount next time
If food is more than 50% Stop feeding next time

Time check food indoor / willing:

Culture period (days) check prepared food Time (GMT)
21-60 2.5 - 2.0
61-90 2.0 - 1.5
> 90 1.5 -1.0

Note:

- The days of changeable weather, rain, blazing sun for only 70-80% of a given food, avoid excess water pollution. Subscribe molting period to reduce food intake and increase after completion peeled shrimp.

- For shrimp farms use feed containing Ethoxyquin

+ With content ≤ 90 ppm: Switch to use these foods do not contain Ethoxyquin 04 days before harvest; Do not use additional foods such as squid liver oil, salmon oil, squid meal, fish meal FMB 60, Fish meal 66%.
+ With 90-120 ppm content: Switch to use these foods do not contain Ethoxyquin 05 days before harvest; Do not use additional foods such as squid liver oil, salmon oil, squid meal, fish meal FMB 60, Fish meal 66%.
+ With 120-150 ppm levels: Switch to use these foods do not contain Ethoxyquin 06 days before harvest; Do not use additional foods such as squid liver oil, salmon oil, squid meal, fish meal FMB 60, Fish meal 66%.

 

2.4.3. Environmental management ponds:

- DO, pH, clarity (measured daily); alkalinity and NH3 (3-5 times day 1 measurement).
- PH and alkalinity are two important factors affecting the life of shrimp. When pH and alkalinity change about appropriate external huge influence to shrimp.
+ Corrected low pH condition: causes algae and watercolor hold appropriate guarantees in reaching the 30 - 40 cm. In the breeding process if pH <7.5 to liming (CaCO3, Dolomite) at a dose of 10 - 20 kg / 1000 m3 water.
+ Corrected high pH condition: used molasses 3 kg / 1000 m3 combined use micro or acetic acid, 3 liters / 1000 m3.
+ Corrected low alkalinity: using Dolomite 15-20kg / 1000 m3 at night until satisfactory.
+ Corrected high alkalinity: using EDTA 2-3 kg / 1000 m3 at night.

Depending on the actual situation pond environment by adjusting the amount of lime and fertilizer accordingly.

- Periodically agricultural liming CaCO3 10 days / times at 20-21h with doses ranging from 10-20 kg / 1,000 m3tuy according to salinity, pH adjustment appropriate:
+ If salinities below 17 ‰, the adjustment of pH from 8.2 to 8.4;
+ If the salinity of 17 ‰, then adjust pH to decrease to 8.0 to 8.2;
+ If salinity = 25 ‰ is adjustable from 7.7 to 7.8.

Till noon the next day 11-12h, inoculated as directed by the provider (the prestigious brand) to clean up the environment.

- If salinity drops suddenly due to rain must be adjusted by residual brine (salt water) or added salt grain.

- When the algae in ponds flourish, watercolor change, diurnal pH> 0.5, should:
+ Replace minimum 30% of the water in the pond;
+ Dissolve sugar 2-3 kg / 1000 m2 and splashing pond at 9-10 am.
+ Run rotor, continuous aeration for several hours.

- When the water temperature rose above 340C pond:
+ Need to reduce food;
+ Additional vitamin C (mixed in food);
+ Increased runtime aeration, aeration;

- When the water temperature drops below 240C pond, the phenomenon of burying their head shrimp, to reduce feed and increase resistance immediately.
- To limit the water into the pond, when necessary, take water in settling ponds and then processed chlorine dose 30kg / 1000m3 fan run constantly, until all chlorine residue is pumped into the pond (through a bag filter).
- In the process of growth, shrimp need a lot of minerals should maintain the alkalinity of 120 mg / liter or more using CaCO3 or Dolomite lime and mineral supplements regularly to the ponds at night 3-5 days / Hard times help fast shrimp shell and molting simultaneously.
- Only when the necessary bactericidal (avoid cases such as shrimp are weakened, is in the process of shedding or have symptoms of liver disease ...).

Note:

- Limit the use of probiotics in the early stage (stage new shrimp drop to 1.5 months).
- First month: Keep the water tank appropriate color (green peeled banana) create stability environmental indicators pH, alkalinity, temperature, dissolved oxygen, algae .. avoid bottom or algae overgrowth.
- May 2nd:
+ Hold appropriate Watercolor (blue-brown, opaque), 1.2 to 1.8 m deep water to fluctuations in temperature, dissolved oxygen, pH daylight and night slow not shocked shrimp. Maintaining the appropriate elements of the 30 - 40cm; 80 -120 alkalinity; 15-25 ‰ salinity; pH from 7.5 to 8.5; Dissolved oxygen> 4 mg / liter; H2S <0.01 mg / l; NH3 <0.1 mg / l.
+ Every 20-25 days water treatment and bottom with probiotics as instructed by the supplier.
+ Fans water, additional aeration from 19h00 to 05h00 oxygen following morning.
+ Can tonic supplement, drug intestinal minerals, mixed into feed feeding follow the instructions of the supplier of branded, reputed to enhance resistance.

 

2.5. Harvest:

Depending on the price that farmers harvest timing accordingly when shrimp reach sizes. Before harvesting should monitor molting cycle of shrimp and shrimp harvested while still limited to avoid soft shell shrimp selling price dropped.