Otherwise, such soils water infiltration "Liners" Figure 13b. Shrimp farms should not be built within mangrove forests, wetlands or any other fragile ecosystem.
Within soil characteristics, it must be considered that it does not contain contaminants that may affect production BMP for site selection for farm location and final product safety. Shrimp farms must be built in areas that have not ever been exposed to agribusiness The following are some general considerations for activities or urban developments, or being affected by implementing best practices in a shrimp farm establishment: For site determination and project development, it must be considered the technical and environmental viability obtained in the economic, technical and environment impact study.
These are key requirements in the process for project legalization Obey national regulations for land using, planning laws and coastal management plans Determining water or soil contamination level at different seasons of the year, based in national regulations Select a site at which water and soil have not previously Figure 13a.
Pond building in a shrimp farm located in an albino area with high in been contaminated by previous use clay and silt adequate texture allowing good dikes compaction. Ponds covered with liners in an intensive system for shrimp reached its carrying capacity for aquaculture production, to avoid leakage due to sandy soil composition.
To consider climate seasonal variations and hydrology for Buffer zones maintenance and corridors between farms the design of structures and water channels, to avoid and other users and habitats costly mistakes and affect the environment Regarding coastal areas, mangrove destruction must be The annual water requirements for the farm, must be avoided and it must be buffer areas determined in the planning process Well water intake and drainage planning, looking for least Potentially acidic and sulfated soils are be avoided for environment impact way and avoiding the re-use of shrimp farm constructions.
Shrimp farms must not be located on sandy soils or unloading or infiltration seawater areas, unless During the planning, design and construction phase of the appropriate technology be used farm, measurements must be considered to mitigate Do not build shrimp farms in traditional areas of birds environmental problems; that is why environmental migration, as there will be problems related to their evaluation is important Figures 14, 15a and 15b.
Improving shrimp farming techniques has advantages as not only considering shrimp farm management, but also farm is integrated in the local environment, causing the least possible disruption to the surrounded ecosystem. A good knowledge of the design principles, construction Photo courtesy of Dr. Code of Practices of the safe design to support and operate pumping equipment, Global Aquaculture Alliance GAA , states that "the facilities and they must provide operational and logistics used in aquaculture should be designed and operated to maintenance conditions; they should also be designed maintain water and protect underground fresh water under an environmentally friendly focus, avoiding oil and sources, to minimize the effluent effects on surface and other contaminant materials leaking to estuarine waters.
BMP play a key role in the reduction or operators Figure Fuel tanks storage should be mitigation of potential impacts during and after shrimp designed and located according to established security farm construction.
In addition, attending thoroughly the standards in each country Figure Pumping equipment selection must consider aspects Every coastal aquaculture operation performed near related to efficiency, cost, durability lifetime and mangrove forests, wetlands and mudflats, must watch their environmental risks associated with its use.
Oil lubricated conservation to maintain industry sustainability itself pumps are a potential risk for estuarine water Figures 18a and 18b. For a proper shrimp farm design, contamination, so it is preferable to use water lubricated standards and proceedings must be considered that involve pumps. Pump motor selection should considered aspects soil properties, slope, water flow and the best hydraulic as efficiency and type of required energy.
At present there section, among others. Figure 15b. Strategic section in a dike of a pond during building of a shrimp Figure Flooding or erosion resulting from this process, will damage the canals, farm infrastructure, nearby activities and the company production system itself. That is why area topographic studies and studying its hydrological before the construction, will let detect where natural water courses in risk are located. Figure 18b. Buffer zone adjacent to a shrimp farm, with natural proliferation of Figure Buffer zone adjacent to a shrimp farm, with natural proliferation of different types of mangroves that serve as shelter for wildlife.
Roadways must have installed adequate sized structures to prevent fresh water stagnation and brackish water flow alteration. One path can act as a dam and cause flooding unless that its drainage be ensured by using adequate sized structures.
During extreme conditions, roads may be swept away by water flows. Administrative, technical and logistical-support facilities for production activities of a shrimp farm, with adequate service roads for vehicles and heavy equipment traffic. Design and construction of supplier water canals, play an important role in the flexibility of pond management, and will have also an effect on some operation potential environmental impact reduction.
These should be designed according with the results of the estimation of the farm maximum daily water demand, including losses by evaporation, water infiltration and leakage. Incoming water sediment load estimations, and required dimensions for a sedimentation area or sediment trap, must be calculated and incorporated into the design by an experienced engineer.
Testing may be required to Figure Main feed warehouse of a shrimp farm receiving shrimp feed transported in a covered truck see right on the picture. It should also be considered the use of two different sedimentation areas within one canal, because one area can be cleaned while the other continues operating.
Regarding drainage canals, they must include in its design and construction, a hydraulic section allowing the efficient management of farm effluents and natural water inflows. Considering the possibility of control water gates for drainage and isolation of tide influence, is a biosafety Figure Concrete stalls used as small warehouse for feed storage; they are strategically located in the pond production area of a shrimp farm and facilitate option that may also reduce operating costs Figure Warehouses must be built and located accord infrastructures that provide personnel comfort and healthy to the stored products.
That is why feed require an conditions. There must be drinking water supply Figure adequate management during storage and distribution in 23a , dining areas Figure 23b and sanitation systems or the field, where must be protected from moisture, direct latrines. The latter must be located strategically in the field sunlight and pest attack Figures 21 and Raised drinking water system supply left and comfortable housing for a shrimp farm workers who live in it right.
It is important that all the actors in the shrimp farms capitalize and implement environmental management and, In order to reduce the risk of introducing diseases and for as part of it, there must be a focus on the reduction of waste traceability ease, there must be an efficient control of in the construction process and during the shrimp personnel and equipment entry and exit Figure 24 , the production phase.
The practice of reducing, reusing and same as considering a disinfection system for them, recycling, must be a rule in the farm depending on the designed so that may not be avoided under any environment and costs.
Waste disposal based on classification and recycling It should be considered in the shrimp farm design and options, must be considered during farm construction and construction, to have the adequate infrastructure and after during production phase, so in each waste production signaling required for permanent implementation of area there were properly located containers.
Although there security, hygiene and biosecurity measures. Its design must include all national established restoration; maintaining riverside vegetation and a buffer zone. When many farms discharge within a same water body, coordination between operators can help preventing problems Minimize degraded areas unused and implement for them reforestation plans or ecological use Have vegetation buffer zones among the mangroves, Figure Thus, has completed they should be designed and efficiently constructed to Ponds must drain completely by using culverts or other avoid water excessive requirements, low water quality drainage systems and increased suspended solids in effluent Whenever possible, water input and output from ponds Farm design and construction must consider control and canals should be separated so incoming and effluent water gates that allow drainage and isolating from tide water never get mixed.
Chlorine and other risks and clear indications of procedures if they become chemicals must be used responsibly, because if they are necessary thrown to the environment, they could cause mortality of During construction, it must consider the strategic flora and wildlife. Farm operation Once harvest is finished, pond must be completely drained Figure This includes pond drying process.
Depopulation performed during dry season, allow also to make improvements and important repairs in farm infrastructure, the same as to restore pond bottoms in order to get a healthy environment for shrimp stocked during next production cycle.
In order to promote a health status improvement of marine shrimp production systems, Competent Authority responsible for aquatic animal health in each country, must encourage producers to run depopulations as a routine strategy for disease control, pondering to producers its beneficial effects relative to the Figure Recently harvested pond under total draining process for a posterior sunshine and wind exposure to soil dry. This will allow reduction of oxidized substances inorganic sulfides BMP for complete pond drainage present in pond soil , accelerates organic matter decomposition and disinfection of pond bottom Figure Incorporate in the farm protocol, properly defined tasks for complete pond drainage activity Hermetically sealing of pond intake and outtake water gates just after harvest be completed When drainage canals have control structures gates , they must be hermetically sealed after ponds harvest to avoid seawater entry and to facilitate pond drying 3.
Pond bottom drying and disinfecting through the sunlight and wind drying and during wet season a partial drying, due to proper effect; note the deep soil cracks.
As an Incorporate depopulation within the farm protocol as example, during biometric samplings, it can be affected net priority activity casts effectiveness, it can also Routine sun and wind drying of pond bottoms and water cause accidents to workers, or can be used by other pond supply canal structures during adequate time, in order to organisms as shelters which may affect shrimp production develop deep cracks of 5 to 10 cm deep results.
Then it must be cleaned and disinfected water In order to make easer soil preparation plowing or intake and outtake gates, pipes, clapboards and racks.
Bottom drying increases soil aeration, which stimulates organic matter decomposition It must be considered during waste management, that there are materials which due to its nature or physicochem- 3. Incin- Pond cleaning must become a routine practice before eration should be avoided due to pollutant release that starting a new production cycle and during it. Foreign affect the environment. Figure 28 and Tanaidacea corrective products amount as needed lime or fertilizers Figure If they are present, it must be considered for each pond Figure On the right the picture shows the bottom of a shrimp pond with holes built by these organisms.
To the right is presented a lump removed from the bottom of a shrimp pond with holes built by these organisms. The use of pesticides or chemicals to eradicate or control It must be avoided samples contamination when using these organisms, must be the last inadequate sampling implements, or due to inadequate resource.
If there is soil uniformity, 3. An important problem is it can be tracked along time according to laboratory test sediment accumulation either from external sources or results from the same farm.
Sediment removal and harvest channel restoration on a shrimp pond bottom left and dikes restructuring right. Shrimp farms must store or dispose removed sediment BMP for sediment management from ponds, canals and settling ponds, without causing environmental impact or land and neighboring water Ponds, canals and settling ponds, should be designed to salinization.
This If sediments are stored outside production area, the site procedure needs a good soil compaction to prevent that this should be designed to minimize material contaminates ponds due to erosion or landslides nutrients infiltration and pollution of underground water Figures 30a and 30b.
Manual sediment removal from the bottom of a shrimp pond after a aeration will be used so compacting would become harvest, when it coincides with the rainy season and it becomes difficult tractors entering to the ponds. Many soils are acidic due to its nature, 31A. Note the having low basic ion concentrations or high amounts of consistency with which lime is being spread on the bottom.
Potential acid sulphated soils, become highly acidic when dried because containing ferrous pyrite is oxidized to sulfuric acid. In shrimp farming, liming is highly effective to neutralizing soil acids and it constitutes a useful management activity economically viable Figures 31a, 31b and 31c. It should exposition to the irritant lime effect, liming process must be taken advantage of pond ploughing, to incorporate lime be done when there are not fast and strong winds or other inputs for soil features improvement.
This new soil condition helps inputs incorporation and action on soil when they are applied 3. It will achieve better soil conditions to 3. The filling process should be slow and under strict supervision, to ensure a good incoming water filtering In order to achieve efficient results when soil ploughing, mesh and bags cleaning ; it must be also implemented a bottom must have an adequate moisture because daily review of them, to ensure their good conditions Figure extremely wet or excessively dry soils, will not get adequate Mesh filters should not be removed from the water performance of the equipment or the ploughing process intake and outtake gates during at least the first 30 days of itself.
For and adequate soil tillage, it should be used appropriate agricultural equipment such as a tiller, rake or rotary tiller, Figure Early shrimp pond filling process using wooden fine mesh filter bags in Figure Tractor pulling a Rotavator during pond preparation for stocking.
Before postlarvae stocking, it should be done a microbiological analysis of pond water, in order to determine whether to apply molasses, probiotic or other inputs aimed to microorganisms growth which may be related to correct postlarvae performance and growth. Thus, promoting microbial balance in the pond water and soil. Late shrimp pond filling process in a shrimp farm still remaining BMP for pond filling wooden filters and fine mesh filter bags to prevent entry of debris and undesirable biological material.
Management plan must involve when and organisms entry and to avoid postlarvae escape how much is used each type of filter, daily inspection and To establish water maturation periods for waters supply storage and maintenance process.
Good filters canal when applicable and for shrimp ponds at least 7 management will avoid frequent changing need, which days means savings on materials mainly wood and labor, the To establish a sampling plan for primary productivity and same as risk reduction of wild organisms income to the microbial load in pond water, pond or shrimp losses by escape. This will promote Implementation of using beneficial microorganisms for phytoplankton development mainly diatoms algae , which pond preparation probiotics and prebiotics , instead of will serve as the initial stocked postlarvae feed.
Ammonia O. When pond waters Postlarvae stocked by shrimp farm ponds, must be has been treated e. Furthermore, LPC allow pond water to get stabilized. Importing water shrimp ponds when postlarvae is going to be stocked: nauplii and postlarvae should be in accordance with national regulations. If there is not a national regulation law, 3. It must be feasibility, are conditioned to a reliable postlarvae source. Ensuring availability of healthy and vigorous postlarvae, is a prerequisite for a good starting of a shrimp farming cycle.
Farm must have records about source and purchase process of each batch of postlarvae, the same as how many and where they were stocked. That is, to keep traceability records for each postlarvae shipping. Low quality and dubious postlatvae source purchase, means a high economic and environmental risk, due to introduction of sick shrimp or pathogen carrier shrimp into the farm, will promote transmission and spread of infectious Figure They should also have good gill development and have a morphological development according to their age stage vs.
Local or foreign postlarvae supplier hatchery, must have strict and well-defined biosecurity procedures and it must ensure their real implementation. Similarly, this hatchery must be certified by the CA, which will ensure buyer shrimp farms the acquisition of high quality postlarvae, disease-free and exotic pathogen-free. In general terms, postlarvae supply hatcheries must comply with the relevant BMP. Postlarvae harvest and shipment process in larval production center, in order to send them to a shrimp farm for ponds stocking.
In order to achieve assessment, and to establish its strength during stress it, it is suggested to seek the support of technician in charge tests. This activity must be performed by qualified of larval rearing.
Postlarvae buyer must be in touch with personnel. Farms must buy postlarvae just from hatcheries submitted to health surveillance by the CA. Late shrimp pond filling process in a shrimp farm still remaining High quality postlarvae, must be infectious organisms free wooden filters and fine mesh filter bags to prevent entry of debris and undesirable biological material.
Avoid stress and rapid environmental uniformity, activity, gut contents and natural peristaltic changes are essential during acclimation Annex 2.
These are framed in a suitable pond water bacterial infection. It is important that when possible, farm Shrimp postlarvae are one of more expensive inputs in develops its own bacteriological history for each pond shrimp farming. Handling and management of postlarvae mainly species from genus Vibrio, Pseudomonas, that includes harvest, packaging, shipping, reception at Aeromonas, Plesiomonas, Streptococcus and farm, acclimation and pond stocking, are extremely critical Flavobacterium , with which farm has established the to their survival.
During acclimation, all efforts of the range of bacteria populations forming colony units - FCU technical staff must focused on minimizing postlarvae that are prevalent during each season of the year dry and stress and mortality, while they adjust gradually to new rainy Figure Based on this, it should be monitored water quality conditions in the ponds.
This support a certain biomass carrying capacity , avoiding is because temperature is lower, and thus reduces postlar- shrimp stress and damage of water quality, as well as vae stress and could become shorter acclimation time. Stocking density used by a shrimp farm, must be planned to optimize productivity and minimize costs Determining an appropriate stocking density, depends on It must be required the hatchery to provide batch number the size and age weight projected to be harvested, water for purchased postlarvae, which is used for traceability quality, pond design, water exchange rates, possibility of records at the larval production center mechanical aeration, staff experience, and farm technical Postlarvae used for pond stocking must be certified as resources and capacity.
Each shrimp company should free of pathogens and they have good health status establish sustainable biomass carrying capacity for each Strictly check of each postlarvae batch to be purchased, pond, according to the proper and individual conditions in order to ensure high quality and good health and to the pond production history. Based on that and conditions taking into account the economic breakeven point of each Adequate pond water operation level before postlarvae farm and market conditions, it can be defined the optimal stocking stocking density for each production system, without affect- Perform monitoring for physico-chemical and biological ing projected economic benefits.
Another source for fishmeal and fish oil, could be ed in feces, come into the water and are spread fertilizing the discard product from aquaculture industry itself. Shrimp feed must not be stored over 3 months and if On the other hand, it must be taken into account the origin happens, it must be not used for shrimp feeding, due to of flour and fish oil used in the artificial feed within the farm.
Fishmeal and fish oil used in farmed shrimp feed, must Thus, feed stores must meet basic conditions to ensure come from natural shoals from ocean zones with an keeping feed its nutritional quality, and must have also an adequate and sustainable fishery management, if possible inventory system for controlling and recording dates and numbers of incoming and outcoming feed batches.
Shrimp feed must have optimal conditions; feed bags contaminated with fungi moldy detected in the feed store on the farm, must be removed and destroyed. If contamina- tion is found in feed that is being downloaded from the truck into the farm, this task should be stopped and whole of the just-arrived feed must be immediately sent back to the factory. Photo courtesy of Mrs. Figure 38b. Shrimp feed temporarily stored on pallets in a warehouse of a shrimp Figure Hydrostability test performed with a feed sample lot on arrival at the farm.
Note the warehouse ventilation, lighting and cleaning conditions, the same shrimp farm, in order to assess its physical quality. Pellets were immersed in sea as the use of wooden pallets and order and space in the stowage system. Note the pellets consistency Photo courtesy of Dr. These water and soil damages could lead to financial losses and major environmental impact. Bulk contact with the pond water Figure Furthermore, pellets that rapidly Daily feed calculation must be done considering the become disintegrated into the ponds, are not consumed by proportion of shrimp population in each pond that is in shrimp becoming a significant organic matter source and pre-molt, molt and post-molt, due to under these molting an expensive pond fertilizer.
Therefore, daily feed dose per pond should be subjected to the Shrimp feed must be periodically checked by technical staff population that is in inter-molt, in order to avoid feed on the farm, to ensure quality and avoid risks by physical or wasting Annex 3. Feed samples must be periodically sent to problem. Problems can occur when farmers decide to independent laboratories, retaining a counter-sample for intensify shrimp farming. Overfeeding can lead to abundant determining of their nutritional composition and physical levels of phytoplankton, zooplankton and non-beneficial characteristics, in order to compare with values supplied by microorganisms and to high DO demand during the night.
From each feed batch received at This occurs as a result of respiration or biological processes the farm, it must be kept refrigerated a 1 kg sample until the of these organisms as well as the oxidation of organic whole batch be used, in order to be used for claims or matter.
Pond bottom can be also contaminated with laboratory analysis required for quality assessment. In addition, daily feed estimate the current biomass of the pond. Feed supply at low temperatures reduced Figure Feed trays are a good tool for the estimation of how much are shrimp eating daily Figures 40 If DO concentration is low for period of time days or and Proper use of feed trays, will ed to reduce or suspend feeding until normalizing water DO help preventing underfeeding and overfeeding.
They can levels. Feed tray review by shrimp farm workers at a pond left ; circular mesh-made feed tray showing feed and shrimp eating during a routine checkup on a shrimp farm. Shrimp feed distributed from a rowboat; this is a good feeding ensure keeping them dry.
Feed warehouse must have practice management to the environmental in a shrimp farm, as long as staff effort be considered. Similarly, the amount of people respective identification by food type and lot and should assigned to these works must be sufficient in order to an never be mixed in the same hold with other inputs e.
It is desirable fertilizers, lime, fuel, tools, disinfectants, etc. This will also prevent uneaten daily consumption monitoring, b pond water feed accumulation in certain pond bottom areas physicochemical characteristics and c pond biomass. Shrimp feed must not contain more nitrogen and The use of feed trays allows monitoring daily feed phosphorus than necessary based on shrimp consumption and prevents overfeeding requirements Feed ration should be supplied only when DO concentrations in pond water be suitable 3.
These should be suitable and the organic matter load into the ponds maintained within acceptable ranges for shrimp The use of medicated feed must be authorized by development.
Otherwise, farming shrimp population could national authorities, have adequate detailed records, be have low growth, pathogen proliferation with disease properly labeled information on pharmacologically outbreaks, eventual mortality and low quality of harvested active substances and be directed for the control of a shrimp. Random samples should be and DO. Organic and inorganic nutrients also participate in taken from all batches sent to the farm and conduct that dynamics, affecting pond microbial populations.
These inspections to determine moisture or fungi are susceptible to change of these factors affecting contamination.
Feed samples must be sent periodically bacterial number and composition. Some aquatic to independent laboratories to determine its nutritional environment variables as pH, temperature and salinity, composition and compare with the values given by the have specific ranges for certain bacteria species. Changes manufacturer in these factors favor proliferation of certain species, Shrimp must not be fed with moldy feed or with feed altering the environmental balance with consequent stored for up to 3 months pathogens dominance.
Contaminated feed detected in the farm warehouse, must be destroyed under safe manipulation and Knowledge of each pond characteristics as behavior of equipment to avoid personnel mycotoxin contamination.
Correct pond bottom preparation between crops, is the first In addition to inadequate levels of physical, chemical and action addressed to ensure that pond maintains acceptable biological parameters in the pond, there are water water and soil quality for a successful shrimp farming.
A contaminants that could compromise the shrimp pond with poor physicochemical parameters and bad production. These may include hydrocarbons, pesticides, health conditions, compromises the water quality and industrial toxic wastes, wastewater from close human shrimp health and development, therefore, not high communities and heavy metals, among others. Detection of production results can be expected. This requires that monitoring be carried Water quality management is the basis for good production out not only in production units tanks or ponds , but also in results and for environmental quality protection.
The farm reservoir channels, pumping stations and water supply must have a plan for monitoring pond physical, chemical sources sea loch or estuaries. Some water quality There are several actions that maintain or improve pond parameters can be measured in the farm laboratory water quality, including liming oxide, hydroxide and Figures 43 and These include at least Secchi disk Figure 45a , dissolved oxygen meter Oxymeter , pH meter, thermometers, microscopes and salinity meter refractometer Figure 45b.
There should be a routine calibration of the equipment used for parameter measuring in order to ensure accuracy and reliability of the data obtained. Routine operation of a laboratory in a shrimp farm, which includes algae counting left , water chemical analysis right and data recording thereof. Water quality monitoring must involve: center. Specific points must be established for the measurement of parameters in each pond, in order to maintain similar conditions along time and to avoid survey data become affected.
Samples that will be submitted to laboratory tests, must be handled adequately until analysis are performed.
Secchi disk design left and how to use it for turbidity Pond water deterioration can severely affect shrimp health measurement in a shrimp pond right. Breadth and complexity of a monitoring program within or outside the farm thereof, must be determined by farmers or by the industry thereof, bearing in mind that the monitoring is frequently restricted by money and resources limitations, including the ability to organize and process collected data.
Figure 45b. This is particularly It is important to maintain an equipment calibration useful in areas where the environment and shrimp farming program in order to obtain reliable results can be vulnerable to other influences such as other industries, agriculture, climate change, etc. In these cases, BMP for water quality monitoring schedule for on-off aerators must be based on the metabolic requirements of the bacterial strains used, in There should be a parameter monitoring protocol where order to maintain optimal pond conditions, although procedures must be well-defined about each parameter heterotrophic systems usually require continuous aeration.
Location must be strategic looking to form a continuous water from ponds , needs to be evaluated with reference to the flow to prevent stratification. Besides reducing organic loads in the Using of aerators powered by combustion engines, must farm effluents, this practice is advantageous because it include a good engine management plan and also a reduces farm inputs from an external ecosystem, helps preventive pollution plan to avoid pond water decreasing the risk of predators and disease spread from contamination with hydrocarbons other farms or wild shrimp, and loss of natural productivity Proper disposal and location of aerators in the pond is within the farm ecosystem.
During dry season summer , water lost working timely and preventively to avoid DO by evaporation must be replaced to avoid high salinity concentration drop to critical levels increase and drastically fall of pond operating water level. Intensive shrimp farming will need aerators based on When extreme high salinity, it is necessary to make pond bacterial-used metabolic requirements and on deep water exchange, decreasing pond water levels and physical-chemical shrimp requirements retrieving with water from the reservoir channel if its salinity 3.
When diseases be present in a pond, no water exchange must be done and water level will be kept It is advisable to minimize water exchange without affecting by replacing when losses by evaporation. If it happens, farms must avoid or reduce water pumping into Fertilization is an important way to maintain nutrient levels the reservoir or pond filling Figure It must be used under technical principles for each product and with knowledge of the type of nutrient and dosage required for each situation.
It is important that the type and dosage of the fertilizer be according to an analysis of pond water nutrient levels and seeking to maintain relations between them e. This is to obtain good primary production, proper microbial balance, acceptable ion balance and good shrimp growth.
Fertilizers contain nutrients that promote phytoplankton growth, which is the first level in the pond food chain and which culminates with shrimp production. Fertilization Figure Shrimp farm pumping station that supplies water to the ponds through should be directed to promote pond beneficial algae growth the reservoir channel; it can be observed behind pumps a well-preserved mangrove with abundant vegetation, which follows the path of the estuary.
A good natural productivity allows savings in artificial feed BPM for pond water exchange pellets. Algae concentration and type phytoplankton in the water column has a direct effect on water quality. They Efforts should be made to reduce water exchange without produce oxygen during daylight due to the photosynthesis affecting shrimp production, anticipating acceptable process produces higher oxygen rate than requested by maintenance of physicochemical parameters and their respiratory processes.
Water recirculation through pond systems will allow cleaning and reuse of the same water, promotes When phytoplankton populations are excessive, algae biosafety, and improves pond water quality and respiratory processes consume more oxygen and it may environmental aspects cause low DO concentrations overnight.
This process season reduces oxygen available for shrimp and can cause mass Physico-chemical parameters of farm water sources must mortalities due to prolonged hypoxia. This group is the main feed source of zooplankton consumed by shrimp in farming ponds. This is generally produced by problems smooth muscle and poor appearance when secondary metabolites 2-methylisoborneol MIB and cooking as in dark or broken hepatopancreas. Metabolites-producing microorganisms which affect shrimp health or quality: on the left dinoflagellates Peridinium and on the right cyanophytes Oscillatoria.
If organisms from water sources that receive farm effluents. Before pond fertilizing it must be verified that the pond is Vegetal products are not easy to be contaminated with closed, it means without water exchange at that time. This heavy metals and antibiotics compared to manures. If will prevent loss of the fertilizers, discharges to the manures are used, they must be first converted into organic environment and it will get good effectiveness in the pond processed fertilizer because this product may have better water.
Getting manure from hours without water exchange. In order to get a faster effect, liquid fertilizers must be used. If Some fertilizers such as ammonium nitrate and sodium granulated phosphorous fertilizers are used, they rush to the nitrate are highly explosive and should not be in contact bottom where they dissolve very slowly and lost large with oil or electrical sparks.
Moisture tends fertilizers to amount of phosphorus as is rapidly absorbed into the form lumps so they must be stored in secure, clean and dry bottom sediment. Waters with high calcium concentrations and other. This warehouse must be properly labeled and if high pH, phosphorus is precipitated as calcium phosphate possible have a shower for any danger of poisoning.
Fertilizers spillage must be avoided because they can contaminate local water bodies with nutrients. Farm staff Due to phosphorus dilution is difficult, it is recommended responsible for fertilizer apply in the ponds, should be to apply it for several days for a better use by trained and wear safety equipment for that purpose gloves, phytoplankton. Granulated fertilizer can be applied through mask, boots and clothing like "overalls" Figure Not underwater platforms, dissolved in barrels or casks and the properly protected personnel are allowed for fertilizer mixture must be applied to the surface of the pond water; application, in order to avoid unnecessary skin lesions or fertilizer can be also placed in a porous bag hung on the respiratory conditions.
If using organic fertilizers is required, manures must be avoided, unless its quality can be confirmed. Worker is protected with gloves and masks to avoid contact with the product. Cadmium, chromium, arsenic, mercury and lead and Photo courtesy of Eng. These measures include the use loads. When used avoid trash or organic waste exposure, among others. These include nets, pyrotechnic elements fireworks , Drainage channels gates must be closed when possible noise producing devices or farm workers to scare away the to prevent entry of unwanted organisms and shrimp birds.
This can prevent wild near mangrove because crabs and other organisms will organisms small fish or crustaceans enter into the ponds enter in the ponds and also avoid shrimp escape. Mesh filters must be in good condition and be appropriate to shrimp size in each pond water incoming and outcoming Figure Structure for sedimentation control and filtration in a reservoir channel of a shrimp farm, which are using bag filters.
Farmers must also be aware of attract predators and competitors their timely cleaning, maintenance and repair during and Use mesh filters in water incoming and outcoming gates after each harvest. Farms must also have replacement minimum 50 to microns elements for these harvest implements tools for Make and adequate pond bottom preparation by drying, immediate replacement in case of being necessary during a disinfecting and treating areas susceptible to predators harvesting process.
Water input gate left and water output gate right in a shrimp pond of a shrimp farm which have mesh filters, bag and wooden seal to prevent the either foreign organisms entry or shrimp escape during farming cycle.
Placement of nets or mesh filters in harvest gates and use crop-capture bags and weighing cones with new or good-condition nets and watch for their review and repair during and after each harvest Have available harvest replacement tools for timely repair when necessary during harvest events 3. The purpose is to prevent shrimp escape causing eutrophication of receiving water body.
Discharged during pond water exchange. AFT can advise the client in the technique choice for shrimp farming. AFT will screen shrimp farming techniques and compare them on total investment, stability of the system and make cost price calculations on the end product. AFT has technical experience with the following shrimp culture techniques:.
A closed recirculation system can be used in existing semi-intensive systems and in super-intensive systems.
Introduction shrimp farming in Biofloc system. Biofloc farming is a technique of enhancing water quality in aquaculture through balancing carbon and nitrogen in the system. The main principle of the Biofloc technique is the generation of nitrogen cycle by maintaining a higher C: N ratio through stimulating heterotrophic microbial growth, which assimilates the nitrogenous waste that can be exploited by the shrimp cultured spices as a feed.
The Biofloc system is not only effective in treating the waste but also grants nutrition to the aquatic animal. The higher C: N ratio is maintained through the addition of carbohydrate source and the water quality is improved through the production of high-quality single-cell microbial protein.
In such conditions, dense microorganisms develop and function both as bioreactor controlling water quality and then protein food source. The Biofloc technology in shrimp farming implemented due to its bottom-dwelling habit and resistance to environmental changes. An improved breeding performance observed in shrimp reared in the Biofloc system when compared to that of normal cultural practices. Biofloc farming has become a popular technology in the farming of Pacific white shrimp.
In addition to the conventional biofilter systems, the Biofloc technology BFT is recently proposed as an alternative solution for wastewater treatment and feed re-utilization, yet it is not suitable for small farms due to intensive aeration, regular waste removal and requirement of additional carbon source to stimulate heterotrophic bacteria growth. Biofloc technology is a technique of enhancing water quality through the addition of carbon sources to the aquaculture system contained in the feed or external carbon sources.
This can minimize water exchange and water usage in aquaculture systems by maintaining adequate water quality within the culture unit.
Biofloc systems support nitrogen removal when the organic matter and biological oxygen demand of the water system are high. Biofloc technology is composed of a variety of microorganisms, uneaten feed, feces, detritus, and suspended particles with water propulsion and aeration. Manipulation of carbon: nitrogen ratio in shrimp ponds encourages the uptake of this inorganic nitrogen into a microbial protein known as Biofloc.
Biofloc farming combines the removal of nutrients from the water with the production of microbial biomass, which can be used by the cultured species, in situ as an additional food source. Then, the C: N ratio in an aquaculture system can be maintained by adding different locally available cheap carbon sources and reducing protein percentage in the feed. Under optimum C: N inorganic nitrogen is immobilized into the bacterial cell while organic substrates are metabolized. The disadvantages of Biofloc include high energy inputs for aerators.
Power failures over an hour in duration can be critical and Biofloc ponds must be lined. The advanced technology also demands a greater need for properly trained technicians. Biofloc systems reduce the spread and effectiveness of pathogens as simultaneously improving shrimp health through better water quality. As such, Biofloc can give us a natural way of producing more seafood sustainably, while concurrently improving farm profitability. Biosecurity is a priority in aquaculture production.
For example, in shrimp farming, the impact of disease outbreaks during the past two decades greatly affected the operational management of shrimp farms worldwide. Biofloc technology brings an obvious advantage of minimizing the consumption and release of water, recycling in nutrients, and organic matter. Also, the pathogen introduction is reduced, improving the farm biosecurity. Biofloc farming technology will enable aquaculture to grow towards an environmentally friendly approach.
Also, the microbial community can rapidly utilize dissolved nitrogen leached from shrimp feces and uneaten food and then convert it into microbial protein. These qualities make a minimal-exchange Biofloc system an alternative to extensive aquaculture.
Microorganisms in Biofloc might partially replace protein content in diets and decrease its dependence on fishmeal. Biofloc is defined as macro aggregates composed of diatoms, macroalgae, fecal pellets, exoskeleton, and remains of dead organisms, bacteria, and invertebrates. And, this microbial protein may have higher availability than feed protein. Ponds should be lined with concrete or high-density polyethylene HDPE , and pelleted grain and molasses are added to the culture water.
Biofloc farming systems remove metabolic wastes from aquatic production systems. Bacteria that convert ammonia into nitrate are cultured in the main rearing tank as opposed to in a separate vessel.
The bacteria form aggregates or Bioflocs suspended in the water column. This is done for many reasons. Eliminating the biofilter reduces costs and then saves floor space. In the case of shrimp, the Biofloc becomes an additional feed source, which decreases the feed conversion ratio or FCR of commercial feeds, again reducing costs.
Commercial interest in Biofloc technology is threefold, for Bioflocs gives high productivity, low feed-conversion ratios, and a stable culture environment.
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