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Is insect farming more efficient than shrimp farming?


Insect farming is sometimes advertised as the way to feed the growing global population with animal protein in a way that is more efficient (in terms of protein yielded/feed consumed) than growing cows, sheep, pigs or fish.

Would insect farming be more efficient than shrimp farming, even though these two broad groups of animals share some similarities in terms of "complexity"?


Insects have a very low feed conversion ratio, which essentially means most of what they're fed turns into edible protein for us. Cows, sheep, pigs, etc. typically have high feed conversion ratios. According to this site: https://in.virbac.com/aqua/health-care/aqua-advice/how-to-get-optimum-fcr-in-shrimp-culture, shrimp have a feed conversion ratio of 1.5 - 1.8., where Acheta domesticus, which is a cricket, is at about 0.9 - 1.1, pork is 5, and beef is around 10 (Huis. A., 2012).. So if we look at feed conversion ratios, they are approximately the same, especially when compared to cows and pigs. What's more efficient to produce depends on the area, and what resources are available. Hope this helps.


What Is The Importance Of Insects In The Ecosystem?

Insect biodiversity on a flower, a butterfly common blue Polyommatus icarus, a bee Anthophila in flight and a shield bug Carpocoris fuscispinus on a yellow Rudbeckia.

The ecosystem can be defined as the complex of organisms, their environment, and their interrelationships in a given geographical area. Natural ecosystems provide invaluable services to humans and other organisms that are essential for their survival and well-being. Services provided by the ecosystem can include the provision of food, water, fiber, and other resources, while non-material benefits of the ecosystem can consist of recreation and aesthetic value. The ecosystem also supports pollination, primary production, decomposition, and soil formation, which is essential for resource production. Other vital aspects of the ecosystem include biological control and feedback mechanisms that ensure consistent delivery of services. While provided at no cost, the value of ecosystem services across the world is estimated at 33 trillion US dollars annually. Ecosystems are also responsible for several “disservices” such as litter, pests, diseases, poisonous and allergenic organisms, animal attacks, and geophysical hazards like floods. Many of the disservices listed are, however, exacerbated by increased anthropogenic destabilization of ecosystem structures, food webs, and processes responsible for the mitigation of events such as storms, floods, and other weather systems.


A six-legged solution to world hunger

In seeking to protect Madagascar&rsquos forests, Fisher and Hugel may have found a solution to one of the world&rsquos most pressing problems. The United Nation&rsquos Food and Agriculture Organization [FAO] says that agricultural production worldwide will have to increase by 70% in order to feed a global population expected to reach 9.1 billion by 2050. Yet agriculture is one of the biggest drivers of natural destruction, threatening 86% of the 28,000 species most at risk of extinction, according to a new report by the UK-based policy institute Chatham House and the UN environment program.

Demand for animal protein in particular is increasing the strain on the environment: 80% of the world&rsquos farmland is used to raise and feed livestock, even though animals only account for 18% of global calorie consumption. Decreasing meat production, says the report, would remove pressure to expand livestock operations while freeing up existing land to restore native ecosystems and increase biodiversity.

There is a sustainable alternative to going meat-free, the FAO says: edible insects. Grasshoppers, crickets and mealworms are rich in protein, and contain significantly higher sources of minerals such as iron, zinc, copper, and magnesium than beef. Yet pound for pound they require less land, water and feed than traditional livestock. Insect farming and processing produces significantly lower greenhouse gas emissions. Not only do insects produce less waste, their excrement, called frass, is an excellent fertilizer and soil amender. Agnes Kalibata, the UN Secretary-General António Guterres&rsquo special envoy for the 2021 Food Systems Summit, says that farming insects could provide an elegant solution to the intertwined crises of climate change, biodiversity loss, hunger and malnutrition. &ldquoInsects are 60% dry weight protein. I mean, honestly, why wouldn&rsquot we use them?&rdquo she says. &ldquoBut we have to be able to put them in a form that is acceptable to different cultures and different societies.&rdquo

Just as in Madagascar, there are technical and cultural barriers to overcome before bugs compete with beef (or any other meat) for space on the global dinner plate. While two billion people, mostly in Africa, Latin America and Asia, already eat insects, in Europe and North America bugs are more likely to be associated with filth, not food. But attitudes are starting to change. Canada&rsquos nationwide grocery chain Loblaws has been stocking locally produced cricket powder since 2018, and in January the European Union food safety agency declared yellow mealworms safe for human consumption, allowing producers to sell insect-based foods throughout the continent. Analysts at Barclays Bank now estimate that the insect protein market could reach $8bn by 2030, up from less than $1bn today. Still, that&rsquos a fraction of beef&rsquos $324 billion.

In order to compete, manufacturers will have to figure out how to successfully market bugs to consumers. The sustainability halo and health aspects may be enough for some, but are unlikely to work on a wider scale, says Cortni Borgerson, an anthropology professor at Montclair State University in New Jersey. &ldquoYou can&rsquot just say, &lsquothis source of protein you&rsquove been eating all your life? Well you can&rsquot have that anymore. Here&rsquos another source, and it&rsquos got six legs instead of four.&rsquo That will never work.&rdquo The goal, she says by video chat from New Jersey, should be &ldquoto find something that people would rather be eating, or would like just as much.&rdquo In other words, insects have to taste at least as good as what they are meant to replace.

In the taste stakes, crickets still come up short. Fried and dusted with chili lime or nacho spice, they don&rsquot taste much different from say, corn nuts or extra crispy shrimp. In powder form, it has a mild, nutty flavor and is best used like a protein boost, sprinkled over porridge, stirred into a vegetarian chili or folded into banana bread batter. Devotees say they can&rsquot get enough, but even they admit that crickets may have a hard getting past that most damning of descriptions&mdasha meat alternative. Madagascar, however, has a better contender: the bacon bug.


Non bee pollinators

Many other insects in addition bees serve as pollinators. Some of the other pollinating insects observed in strawberries are:

Hoverflies (Syrphid fly) (Toxomerus marginatus and Syritta pipiens):

Syrphid fly adult (Family: Syrphidae). Photo: Jeremy Slone

Syrphid fly adult (Family: Syrphidae). Photo: Jeremy Slone

Butterflies ( Vanessa virginiensis) :

Butterfly adult (Family: Nymphalidae). Photo: Jeremy Slone


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Sources: Insects data from (Finke 2002) beef, chicken, and eggs from (USDA 2018)

Sources: Insects data from (Finke 2002) beef, chicken, and eggs from (USDA 2018)

Source: Oonincx and de Boer (2012)


Fishing is a wonderful warm-weather pastime many of us enjoy. At the extension office, we often receive calls in the spring and fall from landowners on how to properly stock recreational ponds with fish.

Miss Kentucky Visits Robert Mayer's Largemouth Bass Fish Farm

Ms. Alex Francke (Miss Kentucky), recently visited Robert Mayer's Largemouth Bass Fish Farm as part of a YouTube series called #MissKYProud. This series is developed by the Kentucky Department of Agriculture and focuses on different Agricultural Production across the state. This video is episode #17 in the series.

Andrew Lohman Starts His Second Trial On LED Lights

Andrew Lohman started his second trial looking at inexpensive light emitting diode, (LED), lights for their use in aquaponic systems. This will be approximately a four week trial evaluating the top four performing LED lights from the preliminary trial study Andrew conducted last November. Andrew is using Buttercrunch lettuce as the plant in the trail, This Buttercrunch lettuce was Developed by Cornell University, this heat-tolerant, Bibb-type lettuce. Tilapia is the fish being used in the research and the average size of the tilapia was 488 grams.

Dr. Semmens And Team Begin Moving Fish For 2021 Research Projects

Preparations are underway to grow channel catfish in floating raceways with three different configurations in 2021. The first device is a grid style airlift, the most common way to aerate and push water through a floating raceway. A second device using a propeller device pushing water horizontally through the raceway will have oxygen sensors and controls to turn on an aerator as needed. The third device is a smaller solar powered propeller unit with controls to turn on an aerator as
needed.

Brood catfish, paddlefish, grass carp, koi carp, bass, and bluegill populate the raceways pond. Cans placed in the pond in 2019 yielded catfish spawn which was hatched and grown to large stocker size in three 0.1 acre ponds the Aquaculture Research Center and stocked in the raceways at the KSU Farm
late in 2020.

This years performance of the three systems will be assessed throughout the growing season. Approximately 4,000 fish, weighing about 0.25 lb each will be stocked in each raceway system for
grow-out.

Shrijan Bajracharya Completes His Research Project

Graduate Research Assistant Shrijan Bajracharya's research project on Pacific White Shrimp lasted 90 days. He did encounter issues with water quality during the study, other than that the overall research went well.

At harvest, Shrijan removed and collected samples of the solids as well as shrimp samples from each tanks. He dried the solids in a oven and grinded them into a powdered and the samples were stored in the freezer for further analysis. The six shrimp samples were dissected and the hepatopancreas was removed, forzen in liquid Nitrogen and then stored at -80°C for analysis at a later date. He will be checking the digestive activity of lipase, amylase, and trypsin.

Shrijan's research has concluded but he still has plenty of work ahead. He has to analyse samples as well as run statics and write his thesis.


Is insect farming more efficient than shrimp farming? - Biology

Food and Agriculture Organization of the United Nationsfor a world without hunger

  1. Identity
    1. Biological features
    1. Historical background
    2. Main producer countries
    3. Habitat and biology
    1. Production cycle
    2. Production systems
    3. Diseases and control measures
    1. Production statistics
    2. Market and trade
    1. Status and trends
    2. Main issues
      1. Responsible aquaculture practices
      1. Related links

      Penaeus monodon Fabricius, 1798 [Penaeidae]
      FAO Names: En - Giant tiger prawn, Fr - Crevette géante tigrée, Es - Langostino jumbo
      Biological features

      The giant tiger prawn inhabits the coasts of Australia, South East Asia, South Asia and East Africa.

      Similar to all penaeid shrimp, the rostrum well developed and toothed dorsally and ventrally. Carapace without longitudinal or transverse sutures. Cervical and orbito-antennal sulci and antennal carinae always present. Hepatic and antennal spines pronounced. Pterygostomain angle round. Stylocerite at first antennular segment. Basial spines on first and second pereiopods and exopods on the first to fourth pereiopods usually present. No fixed subapical spines on telson. Adrostral sulcus and carina are short, not reaching posteriorly beyond midlength of carapace. Gastrofrontal carina absent. Females have closed-type thelycum. Petasma in male symmetrical with thin median lobes. The most distinct features for identification of this species are: fifth pereiopods without exopod hepatic carina horizontally straight and gastroorbital carina occupying the posterior half of the distance between hepatic spine and postorbital margin of carapace. Depending on substratum, feed and water turbidity, body colours vary from green, brown, red, grey, blue and transverse band colours on abdomen and carapace are alternated between blue or black and yellow. Adults may reach 33 cm in length and females are commonly larger than males.

      Shrimp farming has been practiced for more than a century for food and the livelihood of coastal people in some Asian countries, such as Indonesia, the Philippines, Taiwan Province of China, Thailand and Viet Nam. Penaeus monodon was originally harvested together with other shrimp species from traditional trapping-growing ponds or as a significant by-product of extensive milkfish ponds. From 1970-1975, research on breeding was conducted and monoculture techniques in small ponds were gradually developed at the Tungkang Marine Laboratory in Taiwan Province of China and partly at the IFREMER (Centre Océanologique du Pacifique) in Tahiti in the South Pacific. In Thailand, extensive and semi-intensive farms were commercially established in 1972 and 1974 respectively, after the first success in breeding P. monodon at Phuket Fisheries Station in 1972. Between 1980 and 1987 there was a boom of small-scale intensive farms in Taiwan Province of China due to commercial success in formulated feed development, mainly to produce shrimp for export to Japan. However, it is believed that a viral disease outbreak caused the collapse of the industry in Taiwan Province of China in 1987-1988. This led Thailand, encouraged by extremely high prices in the Japanese market due to supply shortages, to replace Taiwan Province of China as the world's leading producer of farm-raised P. monodon in 1988. Later, the culture of this species spread throughout southeast and south Asia, as it can grow-up to a large size (40-60 g) with high value and demand in the international market. The locally adapted culture technology has allowed Thai farmers to overcome serious disease, environmental and trade problems and maintain its status as a leading producer.

      The introduction or importation of wild broodstock is commonly practiced among the major producing countries because local supplies are insufficient and domestication technology has not yet been commercially developed. However, disease-free broodstock are highly desirable and some countries require health certification of imported stock.

      Main producer countries
      An important production is estimated also in China

      Main producer countries of Penaeus monodon (FAO Fishery Statistics, 2006)
      Habitat and biology

      Production cycle of Penaeus monodon

      Due to their larger size and better survival, captured wild seeds were used commonly in south Asia for extensive ponds, which require a minimal amount of seed for stocking. However, the use of wild seeds has been reduced, due to overfishing and the outbreak of white spot disease in shrimp nursery grounds. Therefore most Penaeus monodon grow-out farms now rely solely on hatchery-produced seeds.

      Healthy females (25-30 cm body length and 200-320 g weight) and males (20-25 cm 100-170 g) captured from the wild are preferably used as broodstock in the induced ovarian maturation process. Broodstock from greater depths (60-80 m), or more than 20 miles offshore, are preferable due to the lower prevalence of shrimp diseases, which are higher in coastal shrimp farming areas. Once the shrimp have recovered from transport stress for a few days, they are stocked in a circular maturation tank that is normally covered and kept in a dark room. The same stocking density (2-3/m²) is used for both females and males. Shrimp are subsequently induced to moult by manipulating the salinity of the water. After mating has occurred, which is easily determined by the presence of a spermatophore in the thelycum and hardening of the shell, the eyestalk of females is unilaterally ablated for endocrine stimulation. Broodstock are fed with squid, mussel or cockle meat, supplemented by polychaete or Artemia biomass to enhance reproductive performance.

      The early stage of ovarian development can be first observed within a week after ablation. Later, gravid females with ripe stage eggs, which can be observed by the opaque diamond-shaped ovary under torchlight, are collected and transferred into spawning tanks. After spawning, these females can be re-used in the maturation process a few times, while males can be further used for several months, depending on prawn health and tank conditions.

      Whether the spawners are caught directly from the sea or from an induced maturation tank, they generally spawn on the first or second night in the hatchery. However, spawning can be delayed for long distance or overnight transportation if each spawner is placed tightly in a PVC pipe to straighten its body. Gravid females should be placed individually in a small spawning tank to avoid the spread of disease that may occur in mixed spawning.

      After spawning, eggs are generally kept in the same tank for fertilization until hatching. Nauplii are then collected and cleaned (rinsed with flowing seawater to remove the fat and debris released by the spawner) for transfer to larval rearing tanks or for transportation to other remote hatcheries. In Thailand, thousands of specialized small-scale or backyard hatcheries in inland areas buy nauplii and grow them to PL 12-15 because they cannot conduct the costly broodstock maturation operation. Broodstock maturation facilities located at the coast require a large volume of clean, clear seawater, while closed system larval rearing generally needs much less seawater. Therefore the inland hatcheries, whose land costs are much lower, are able to operate economically by purchasing seawater or brine that has been transported by trucks from the sea or from salt pans.

      Smaller indoor concrete tanks (4-5 tonnes) than those originally used have now proved more efficient and manageable for larval rearing, particularly during the application of closed systems for disease prevention. If an outdoor system is unavoidable, due to economic constraints, tanks should be covered by black cloth or roof tiles in order to avoid the diurnal fluctuation of water temperature, and also to reduce light intensity. Nauplii are usually stocked at 100 000/tonne and cultured up to late mysis or early PL with approximately 70-80 percent survival rate. They are then transferred to a new tank and cultured up to PL 12-15 a further 70-80 percent survival rate is achieved in this stage. Diatoms (either Chaetoceros , or Skeletonema or Tetraselmis ) that have been reared in monoculture, are fed at an approximate density of 30 000-50 000 cells/ml, starting from the protozoea stage and continuing until early PL (4-5). Diatoms can be replaced by micro-encapsulated diets or dry formulated feeds if their production is interrupted by rain. Artemia nauplii, at an average of 50 g of cysts per 100 000 larvae are given from mysis up to early PL stage. Artemia flakes are also used to supplement Artemia nauplii for cost reduction. From PL 4 to PL 15, artificial diets are commonly used to reduce the deterioration in water quality that occurs when fresh feed is applied. From hatching, it takes about 26 days to reach PL 15.

      Due to its benthic habit, the harvesting of nursed juveniles in separate earthen ponds is difficult thus nursing of hatchery produced postlarvae is impractical. Nursing in concrete tanks also yields poor survival, due to the cannibalistic behaviour of PL at high stocking densities. Since intensive ponds are well treated to eliminate all fish predators, it is safe to stock PL 15 prawns directly into the grow-out ponds. If the pond has not been well-prepared in time, or some predators have been observed, or the PL seem weak, PL 15 may be acclimatized by impoundment in nets, pens or small enclosure within grow-out ponds for less than a week before release.

      In semi-intensive ponds, where postlarvae are not fully fed by artificial diets and some fish predators still remain, postlarvae are commonly nursed for a few weeks in an earthen compartment (5-10 percent of pond area) within the grow-out ponds. This enables the feed to be concentrated in this small nursing area, resulting in juveniles that are larger and thus better able to escape from the remaining fish predators after release into the grow-out pond.

      There are three on-growing culture practices: extensive, semi-intensive and intensive, which represent low, medium, and high stocking densities respectively. Due to its benthic feeding habit Penaeus monodon is commercially cultured only in earthen ponds, under widely varying salinities from 2 to 30&permil.

      Commonly found in Bangladesh, India, Indonesia, Myanmar, the Philippines and Viet Nam, extensive grow-out of shrimp is conducted in tidal areas where water pumping is unnecessary. Ponds with an irregular shape according to land boundaries are generally larger than five hectares and easily constructed by manual labour for cost reduction. Wild seeds, which either enter the pond through the gate by the tide or are purchased from collectors, are usually stocked at a density not exceeding 2/m². Shrimp feed on natural foods that enter the pond regularly on the tide and are subsequently enhanced by organic or chemical fertilizers. If available, fresh fish or molluscs may be used as supplementary feed. Due to the low stocking densities, larger sized shrimp (>50 g) are commonly harvested within six months or more. The yield is lowest in these extensive systems, at 50-500 kg/ha/yr. Due to the increase in land costs and the shortage of wild seeds, almost no new extensive farms are being constructed today. After gaining experience in shrimp farming, many farmers have upgraded their ponds to semi-intensive systems to provide better incomes.

      Semi-intensive ponds (1-5 ha) are commonly stocked with hatchery-produced seeds at the rate of 5 to 20 PL/m². Water exchange is regularly carried out by tide and supplemented by pumping. The shrimp feed on natural foods enhanced by pond fertilization, supplemented by artificial diets. Production yields range from 500 to 4 000 kg/ha/yr.

      Intensive farms are commonly located in non-tidal areas where ponds can be completely drained and dried before each stocking. This culture system is found in all Penaeus monodon producing countries and is commonly practiced in Thailand, the Philippines, Malaysia and Australia. Ponds are generally small (0.1 to 1.0 ha) with a square or rectangular shape. Stocking density ranges from 20 to 60 PL/m². Heavy aeration, either powered by diesel engines or electric motors, is necessary for internal water circulation and oxygen supply for both animals and phytoplankton. Feeding with artificial diets is carried out 4-5 times per day followed by feed tray checking. Final FCR is normally between 1.2:1 and 2.0:1. Since the outbreak of white spot disease, reduced water exchange and closed systems have become commonplace, due to their lower risk of introducing viral diseases through intake water. However, feed and phytoplankton blooms need to be carefully monitored and managed to avoid deterioration of the pond bottom and water quality due to wastes. P. monodon has a habit of slowly nibbling feed on the pond bottom this causes substantial nutrient losses because pellet stability is generally not longer than two hours. Efficient feed management is the major criteria for a successful crop, since feed represents over 50 percent of the production costs in intensive systems. Water quality parameters such as pH, salinity, dissolved oxygen, alkalinity, Secchi disc, H 2 S and unionised ammonia are regularly measured. If closed system culture is applied, stocking should be minimized, otherwise the pond must be harvested earlier (within 3.5 months instead of 4-5 months) and smaller shrimp will be yielded (20 g, instead of 30-35 g as achieved in semi-intensive and intensive systems with water exchange). Production yields of 4 000 to 15 000 kg/ha/yr are commonplace.

      Bamboo traps are traditionally used for the partial harvest of selected large shrimp in extensive culture. Semi-intensive ponds are commonly harvested by draining the pond by tide through a bag net installed at the outlet sluice gate. Intensive ponds are normally harvested similarly to semi-intensive ponds. If the tide does not allow harvesting, the drainage canal can be blocked to allow the water to be pumped out to reduce the water level. It is still necessary to pick the remaining shrimp by hand after the pond has been drained.

      In Thailand, artificial sluice gates are temporarily installed inside the pond for the harvesting of many closed system ponds where a sluice gate for water exchange is not necessary. Shrimp are then trapped in this artificial gate during the pumping out of the water. For the live shrimp market, ponds are partially harvested by cast net in the early morning. Due to its burrowing habit, a drag net is not practical unless it is installed with electric shock gear to stimulate the shrimp to jump.

      If shrimp are sold directly to processing plants, specialized teams for harvesting and handling are commonly used to ensure the first grade quality of their raw materials. After rough sorting, shrimp are washed, weighed and immediately killed in iced water at 0 °C. The most difficult job is to clean the shrimp picked by hand from pond bottoms at the end of the harvest, because they contain a lot of mud, organic matter and debris. Shrimp are then kept in ice in insulated containers and transported by small pick-up trucks for short distances or by large insulated trucks over long distances, either to processing plants or shrimp markets. For transportation of live shrimp from farms directly to aquarium tanks in restaurants, the shrimp are kept in aerated plastic containers at a density of 0.2-0.3 kg/litre of water. The containers are typically placed on small pick up trucks with a roof. For the export of live shrimp from Thailand to Hong Kong and China, water temperature is gradually reduced to 16-17 °C until the shrimp become inactive. The dormant shrimp are then packed alternately in layers of chilled sawdust or polystyrofoam beads in insulated boxes for export by air. This dry packing can minimize freight costs and shrimp can survive for 12-15 hours. Domestic markets mainly require chilled product supplied directly from farms or from shrimp markets.

      In processing plants, shrimp are properly cleaned and sorted according to export standard sizes. Depending on market requirement, shrimp are processed in several categories before quick freezing at -10 °C and stored below -20 °C for further export by ship or air cargo. Due to an increasing demand and higher profit margin, many processing plants increasingly operate value-added product lines.

      Production costs always vary depending on the site, season, scale of production, water management system (such as water exchange versus closed system), irregular production yield affected by culture problems, outbreak of diseases, etc. Operational costs for seed production regionally average at about USD 2.5/1 000 PL.

      Production costs for adult shrimp are summarized as follows (USD/kg):

      ExtensiveSemi-intensiveIntensive
      Seed0.530.580.59
      Feed&ndash1.412.02
      Labour0.850.200.19
      Electricity & fuel0.210.360.33
      Chemical, materials & supplies 0.160.180.26
      Overheads&ndash0.130.37
      Depreciation0.200.660.52
      Total 1.95 3.52 4.28

      The major disease problems are included in the table below. There are no chemicals or drugs available to treat the viral infections listed but good management of pond, water, feed and health status of stock inputs can reduce their virulence. Outbreaks of the most serious virus (WSD) always occur after dramatic changes in water parameters such as temperature, salinity caused by heavy rain, DO 2 , hardness, and the stress to shrimp caused by deterioration in water quality and pond bottom environment. Pond preparation by proper bottom cleaning or regular scraping of the fouled layer is also a key factor for prevention of the shrimp stress caused by built up waste and toxic gases, and also for the elimination of virus carriers, particularly crustaceans. For confirmation, the Polymerase Chain Reaction (PCR) test for white spot disease or other viruses is widely used for screening of broodstock before spawning, nauplii before larval rearing, late PL before pond stocking, and shrimp in ponds for regular monitoring.

      In some cases antibiotics and other pharmaceuticals have been used in treatment but their inclusion in this table does not imply an FAO recommendation.

      DISEASEAGENTTYPESYNDROMEMEASURES
      White spot (WSD)Otherwise known as WSBV, WSSVPart of the white spot syndrome baculovirus complex VirusAcutely infected shrimp show rapid reduction in food consumption lethargy high mortality rates with cumulative mortalities reaching 100 percent within 3 to 10 days of the onset of clinical signs acutely infected shrimp often have loose cuticle with white spots (which represent abnormal deposits of calcium salts by the cuticular epidermis) of 0.5 - 2.0 mm in diameter that are most apparent on the inside surface of the carapace in many cases moribund shrimp display a pink to reddish-brown colouration due to expansion of cuticular chromatophores & few if any white spotsScreening of broodstock, nauplii, PL & grow-out stages avoiding rapid changes in water conditions avoiding shrimp stress avoid use of fresh feeds, particularly crustacean minimizing water exchange to prevent virus carriers entering the pond treating infected ponds or hatcheries with 30 ppm chlorine to kill infected shrimp & carriers disinfect associated equipment
      Yellowhead (YHD) Also known as Yellow-head shrimp disease, Yellow-head virus (YHV), Yellow-head baculovirus (YBV), Yellow-head disease baculovirus (YHDBV) Not yet described VirusAcute epizootics with high cumulative mortalities that may reach 100 percent within 3-5 days after appearance of clinical signs infection is horizontally transmitted PL 15 have been found to be resistant but PL 20-25 & on-growing juveniles through to sub-adults are highly susceptible initially, feeding increases, followed by reduced feeding in later stages of the disease pale body yellowish swollen cephalothorax & hepatopancreas whitish-yellowish-brownish gills presumptive diagnosis can be made on basis of pond history, clinical signs, gross changes & histopathologyScreening of broodstock before hatchery operation & PL before stocking in pond avoiding rapid changes in water pH, alkalinity, & dissolved O 2 avoiding fresh aquatic feeds proper cleaning of pond bottom before stocking infected ponds & hatcheries must be disinfected similar to WSV (see above)
      Baculoviral Midgut Gland Necrosis (BMN)Also known as midgut gland cloudy disease, white turbid liver disease, and white turbidity diseaseBaculovirusVirusGenerally infects larvae & early postlarval stages in which it can cause high mortalities apparent white turbidity of the hepatopancreas caused by necrosis of tubule epithelium & possibly also the mucosal epithelium larvae affected but later stages (late postlarvae) tend to show resistance source of infection documented as wild-caught female spawners larvae float inactively on the surface & exhibit a white midgut line through the abdomenWash fertile eggs through a soft gauze by running clean seawater to remove excrement or faeces of spawner if infected, culture facility must be disinfected to avoid re-introduction of virus
      Nuclear Polyhedrosis BaculovirosesAlso known as Monodon baculovirus disease (MBV)BaculovirusVirusLethargy, anorexia, dark coloured shrimp reduced feeding & growth rates often increased surface & gill fouling with various epibiotic & epicommensal organisms severely affected larvae & postlarvae may exhibit a white midgut line through the abdomen acute MBV causes loss of hepatopancreatic tubule & midgut epithelia &, consequently, dysfunction of these organs, often followed by secondary bacterial infections linked with high mortalities (>90%) in late postlarvae & juvenile shrimp in many culture facilities usually juvenile & adult P. monodon are more resistant to MBV than larval shrimp MBV may predispose infected shrimp to infections by other pathogens Reduce stocking density, use of chemicals & environmentally induced stress prevent contamination of fertilized eggs from spawner faeces by washing in formalin or iodophore treated seawater if infected, culture facility must be disinfected & stock should be removed & sterilized

      Suppliers of pathology expertise

      No specific institutes or laboratories named, but shrimp pathology expertise is now readily available.

      Total aquaculture production of Penaeus monodon increased gradually from 21 000 tonnes in 1981 to 200 000 tonnes in 1988 then it sharply increased to nearly 500 000 tonnes with a value of USD 3.2 billion in 1993. Since then, production has been quite variable, ranging from a low of 480 000 tonnes in 1997 to a high of 676 000 tonnes in 2001.

      The major producers of Penaeus monodon include Thailand, Viet Nam, Indonesia, India, the Philippines, Malaysia and Myanmar. Since 2002, production of Penaeus monodon has been unofficially reported to have declined, particularly in Thailand and Indonesia, because of substitution by Litopenaeus vannamei in many farms.

      Market and trade

      Frozen head-on, head-off, and peeled shrimp used to be the major products for export to the main markets, which are USA, EU and Japan. Later, value-added products, such as microwavable or ready-to-cook tempura, sushi, shaomei, hargao, straightened, skewered, battered and breaded, spring roll and balls mainly processed in Thailand, have become increasingly popular. This has been because tight economic conditions in many developed countries limit frequent dinner in restaurants, and the time for cooking at home is scarce. Chilled product, which is sold in domestic markets, is generally non-exportable grade and shares less than 10 percent of all markets. Live product, which is mainly for domestic Chinese restaurants with some exports to Hong Kong and China, also shares less than 2 percent.

      Prices and market statistics

      In financial value, Penaeus monodon is the most important traded aquaculture commodity in Asia. C&F prices in Japan, whose market mainly requires large headless (16/20 size) shrimp from extensive and semi-intensive farms in Indonesia, India and Viet Nam, varied from USD 9-14/kg during 2001-2004. The US market purchased mainly small headless (21/25 size) shrimp (both peeled and shell-on) from intensive farms in Thailand and India at C&F prices ranging from USD 7-13/kg during the same period. The EU market, which mainly requires small head-on shrimp (31/40 size) from South East Asian intensive farms, paid C&F prices between USD 4.7 and 9.0/kg during 2001-2004.

      Sanitary standards, standards for the uses of drugs and chemicals, and common food safety regulations for seafood (particularly shrimp) are already high in all major import countries. However, the EU market has more strict regulations (zero tolerance) on residues of chemicals and antibiotics, as well as the trade privilege or Generalized System of Preference (GSP) on import tax and HACCP. The US market enforces more strictly on a sanitary standard such as HACCP or Sensory Assessment. There are also additional regulations in the US regarding anti-dumping of imported shrimp, and the application of Turtle Excluder Devices (TEDs) on wild shrimp fishing fleets in exporting countries.

      • Domestication technology, which also leads to the efficient development of disease-free broodstock similar to those for Litopenaeus vannamei , is a major topic for on-going and future research in various institutions, including private sector organizations all over the world.
      • Vaccination and effective treatment of shrimp viruses.
      • Replacement of non-environmental friendly and costly fishmeal and Artemia in shrimp feeds.
      • Efficient water treatment system for closed systems.

      Expansion in aquaculture production of Penaeus monodon has not been as great as was originally expected, due to a number of causes, including major problems with viral disease outbreaks, shortages of broodstock, market competition and trade barriers. In addition, many farmers that originally reared Penaeus monodon have replaced this species with Litopenaeus vannamei , for which culture and domestication technologies are much simpler. L. vannamei disease problems are less severe, particularly for culture in inland freshwater ponds. Due to its lower price, this new species can be increasingly sold in domestic markets, which ensures stable incomes for farmers instead of only relying on the unstable export price. Shrimp farming will be more sustainable if farmers can shift production to other species when the existing cultured species faces problems. Decreasing P. monodon production can also improve the status of its broodstock in the wild in the future because less will be caught and less disease from grow-out ponds will be introduced into the sea. Due to this alternative species, the growth of P. monodon production is predicted to slow in the immediate future. Later, it may increase again if the research needs outlined above are addressed, thus improving the sustainability of production and reducing operational costs.

      In general, Penaeus monodon is the most prominent farmed crustacean product in international trade and has driven a significant expansion in aquaculture in many developing countries in Asia. Market prices during its early development were quite good due to little competition and strong demand from the Japanese market. International markets appear to have become almost saturated since global production reached 600 000 tonnes/yr. The price for P. monodon has since fallen, particularly during the booming of the production of Litopenaeus vannamei in Asia from 2001-2004. However, its price is still higher than L. vannamei . In the future, the market for P. monodon is expected to be less bright than it was in 1990s, due mainly to the saturation of export markets and reduction in world economic growth, as well as the emergence of non-tariff barriers in shrimp trade (such as anti-dumping rules), chemical residues, food safety, certification and eco-labelling in some importing countries. There has been increasing change in consumer preference from shrimp to marine fish, due to the lower cholesterol and higher omega-3 in fish.

      In order to continue the growth of shrimp farming smoothly in the long term, domestic consumption should be promoted to avoid the problematic export markets. However, the domestic price should be reduced in order to encourage local consumption, through the use of advanced, efficient and sustainable culture systems. This is similar to the advanced chicken or salmon farming systems that have reduced production costs and guaranteed survival. Shrimp farmers in Asia should select whether to stock either P. monodon or L. vannamei according to the foreseen market and operational problems such as competition, climate and disease outbreak season.

      • Use of mangrove ecosystems for pond construction.
      • Salinization of groundwater and agricultural land.
      • Pollution of coastal waters due to pond effluents.
      • Biodiversity issues arising from collection of wild seed and broodstock.
      • Social conflicts with other users of resources.
      • Farm discharges, causing self-pollution in shrimp growing areas as well as viral disease outbreaks.

      Overfishing of wild seeds and broodstock has been relaxed due to disease prevention measure and the shift to alternative species that can be domesticated. Shrimp farming in Asia does not create as many social conflicts with local communities as in Latin America, where large-scale farms are commonplace, because it is mostly operated by small-scale farmers that originate from coastal communities and own less than 5 ha of land. The shrimp industry also employs hundreds of thousands of rural people for farm operations and supply industries, as well as for shrimp processing and distribution. Enriched nutrients in shrimp farm effluent have proved to enhance the growth of aquatic animals and mangroves.


      'Subterranean estuaries' crucial to sustainable fishing and aquaculture industries

      Pioneering research, led by a team from Trinity College Dublin and the Marine Research Institute of the Spanish Research Council (IIM-CSIC) in Vigo (Galicia, Spain), suggests "subterranean estuaries" may be critical in managing sustainable fishing and aquaculture -- two growing industries of global importance.

      Subterranean estuaries are analogous to surface water estuaries, where freshwater flowing out to sea mixes with seawater, but are instead located underground, invisible to the naked eye. Yet the newly published research shows these hidden features are very important in the ecology of coastal systems and in filtering pollutants -- some of which have been slowly travelling to sea for decades having leached from agricultural soils.

      The research, just published open access in Limnology and Oceanography, uncovered subterranean estuaries in the Ria de Vigo in Galicia (one of the most productive coastal ecosystems in Europe and leader in bivalve production for human consumption) and assessed their importance to the coastal environment.

      By employing a selection of natural environmental tracers that carry the chemical fingerprints of groundwater sources on land out to sea, the team estimated that almost 25% of the continental freshwater discharged to the Ria de Vigo comes from this invisible source.

      The Biogeochemistry Research Group of Trinity's School of Natural Sciences, led the study (Project SUBACID). Explaining the significance of the work, and its wider implications for Irish waters, Carlos Rocha, Professor in Environmental Change, said:

      "Bivalve aquaculture is a strategic, expanding sector in Irish sustainable development and features highly in the national plans to diversify food production. While our work was conducted in the Ria de Vigo, this area was carefully selected because of its capability to support aquaculture and its biogeographic similarity to parts of the Irish coastline.

      "These subterranean estuaries have a high capability to filter out pollutants, like fertilisers, from freshwater. Given the extent to which they supply large ecosystems with incoming freshwater, they have a much more important role to play than many would have believed."

      Juan Severino Pino Ibánhez, researcher from the Marine Research Institute-CSIC (Spain), added:

      "We will now focus in more detail on which specific ecosystem services these invisible structures provide, and how they might affect, for example, the ongoing threat to this industry posed by ocean acidification caused by anthropogenic CO2 emissions to the atmosphere.

      "We are currently strengthening the collaborative network established with the Marine Research Institute of Vigo to elucidate the functioning of these hidden ecosystems and their role in coastal health and resilience. Lessons learnt in Vigo together with ongoing research made by our group in Irish coastal ecosystems will help to understand the future of Irish coastal ecosystem services and food production."


      CONSERVATION

      Insects are generally considered a nondomesticated resource, as few species are reared. Caterpillars gathered in the wild have a comparative advantage over those edible species gathered from crops as they are free from pesticides. However, overexploitation has led to the disappearance of mopane caterpillars (Imbrasia belina) from parts of Botswana (87) and South Africa (68). To address this problem some community leaders have placed embargos on harvesting during certain periods (90), but modeling has shown that this may not lead to sustainable harvesting of the larvae (6). The logging of commercial sapelli trees (Entandrophragma cylindricum) in the Central African Republic threatens the survival of the important caterpillar Imbrasia oyemensis (147). To allow regeneration of the tree species, the present forest concession rules require loggers to leave at least one seed tree of sapelli for every 10 ha of logged forests. This may result in a significant reduction in the caterpillar supply as well as in the regeneration of young sapelli trees, as harvesting caterpillars is more easily done by cutting down the trees. In Benue State, Nigeria, 10 most preferred and consumed insect species have been identified, but deforestation, water pollution, and bush burning reduce their availability (3). In Mexico, 14 edible insect species were documented as threatened due to overexploitation or ecosystem degradation (121). Overexploitation may occur because of the higher demand resulting from an increase in human population or when harvesting is carried out by nonnative and nonqualified independent harvesters. For example, when collectors did not respect harvesting rotations of the weaver ant Oecophylla smaragdina, they depleted this resource in Indonesia (26). Ecosystem degradation may occur due to pollution (aquatic Hemiptera) or pesticide use (Aegiale hesperiaris in agave) (121). In France, until the mid-1980s, mayflies (Ephoron virgo), also called manna, were collected in large quantities by local fishermen along the Saône River and sold to middlemen and traders to be mixed into animal feed (mainly for farm birds) (27). However, development of the river banks very likely degraded mayfly habitat. Possible measures to conserve insect populations include documenting their significance to people's livelihoods, assessing the links between insect collection and the ecosystem, and enforcing legislation.

      However, methods conducive to insect survival and reproduction should also be developed, e.g., providing food resources, creating suitable habitats, harvesting sustainably (e.g., allowing repair of ant and wasp nests), and employing (semi)rearing like that being done for wild silkworms. In the last case, the African wild silkmoth Gonometa postica was reared in semicaptivity by using net sleeves on the branches of host plants to protect the larvae against predators and parasitoids (105). Other practices include the transfer of edible caterpillars to trees near the homestead (80) or to other tree species to improve their flavor (131).


      Acknowledgements

      The authors would like to thank Hans Smid (www.bugsinthepicture.com) for allowing us to use the photos of two insect species (Figs. 1 and 2). Photographs were optimized for increased depth of field by making multiple images taken at various distances with a camera (Canon M5) mounted on a Stackshot automated macro rail (Cognisys, Traverse city, MI, USA). Resulting stacks of images were processed in Zerene stacker software v. 1.04 (Zerene systems, Richland, WA, USA).