AQUACULTUREAQUACULTURE-Presented By

-Priyanka Kulur Nayak

NEED FOR AQUACULTURENEED FOR AQUACULTURE"Aquaculture is the farming of aquatic organisms, including fish, mollusks, crustaceans and aquatic plants. Farming implies some form of intervention in the rearing process to enhance production, such as regular stocking, feeding, protection from predators, etc. Farming also implies individual or corporate ownership of the stock being cultivated. For statistical purposes, aquatic organisms which are harvested by an individual or corporate body which has owned them throughout their rearing period contribute to aquaculture, while aquatic organisms which are exploitable by the public as a common property resource, with or without appropriate licenses, are the harvest of fisheries" (FAO 1997) [1].

(a)

(b)

(C)

BIOTECHNOLOGY FOR BETTER FISH FEED BIOTECHNOLOGY FOR BETTER FISH FEED [4][4]

ENERGY REQUIREMENTSENERGY REQUIREMENTS

Fish have low energy requirements. Fish meal is made out of variety of ingredients, including fish and proteins [6].

Fish do not have to maintain body temperature. In mammals high heat increment is due to urea or uric acid excretion. Fish have low heat increment due to ammonia excretion [6].

They utilize less energy to maintain their position [6].

They lose less energy in protein catabolism and excretion of nitrogen [6].

Feces energy (FE)

Gill excretions (ZE)Urine excretions (UE)

Heat increment (HiE)

Maintenance (Hem)

Growth Fat Reproduction

(Digestibility) %DE = (IE – FE) / IE

(Absorption) %ME = [IE – (FE – UI – ZI)/IE

Partitioning of dietary energy [5]

DIETARY REQUIREMENTS DIETARY REQUIREMENTS [7][7]

Proteins: Fish require all the 10 essential amino acids in their diet. Fish feed prepared from soyabean meal are low in methionine hence need to be added externally for optimal growth and health.

Lipids: Serve as transporters for fat – soluble vitamins which include triglycerols, fatty acids of the omega 3 and 6 (n -3 and n – 6 families), SFA, PUFA, HUFA.

Carbohydrates: reduce feed costs, assist in feed manufacturing, stored as glycogen and 20% is used by fish.

Macro minerals: sodium, chloride, phosphorous and potassium regulate osmotic balance, help in bone formation and integration.

Micro minerals: copper, chromium, iodine, zinc and selenium are absorbed through gills and skin.

Water soluble vitamins: Vitamin B, C, choline, inositol, Biotin, pantothenic acid, ascorbic acid.

Fat-soluble vitamins: Vitamin A,D,E,K, retinols, cholecaciferols, tocopherols.

Nutrients Amount

Protein 18 – 50%

Lipid 10 – 25%

Carbohydrate 15 – 20%

Ash < 8.5%

Phosphorous < 1.5%

Water < 10%

Vitamins Trace Amounts

Minerals Trace Amounts

FEED MANAGMENTFEED MANAGMENT [7] [7]

Feeding Rate: Fish should be fed 1 -4% of their body weight per day. Fish should be fed only the amount of feed they would consume in less than 25 minutes. [7]

As feed is expensive Feed Conversion Ratio (FCR) and Feed Efficiency (FE) are important calculations for the farmer. [7]

FCR = weight of feed fed to fish weight gained by fish

FE = 1/FCR

Fish do not exhibit total efficiency as energy is used up for metabolic heat, respiration, digestive processing, salt balance, nerve impulses and swimming

[7].

Feed Care and Storage Management [7]

Bulk feeds need to protected from heat and moisture. [7]

Fish do not consume broken pellets. [7]

Feed should not be stored more than 90 to 100 days and moldy feed should be discarded. [7]

Fish Wastes need to be managed carefully as overfeeding leads to low dissolved oxygen levels, water pollution, increased biological oxygen demand and increased bacterial loads. [7]

(d)

REPLACEMENT OF FISH MEAL FOR REPLACEMENT OF FISH MEAL FOR PACIFIC WHITE SHRIMP PACIFIC WHITE SHRIMP [8][8]

A study was carried out to prove that fish meal can be replaced in commercially manufactured shrimp feeds, with vegetable protein sources in combination with poultry by – product meal without any negative effect on the performance or production or economic returns of L. vannamei

Parameter 9% fish meal

0% fish meal

Final yield (kg ha -1) 5,847 6,347

Production value (USD ha−1) 21,134 23,445

Total feed inputs (kg ha−1) 7,244 7,232

Feed price (USD kg −1) 0.531 0.515

Total feed inputs cost (USD ha−1) 3,849 3,723

Partial gross returns (USD ha −1) 17,285 19,722

Ingredient 9% fish meal

0% fish meal

Soyabean meal 32.48 39.52

Fish meal - Menhaden

9.00 0.00

Poultry by – product meal

16.00 16.00

Milo 35.47 30.68

Corn gluten 0.00 4.84

Fish oil 3.96 4.72

Di – calcium phosphate

1.50 2.65

Bentonite 1.00 1.00

Mold inhibitor 0.15 0.15

Mineral premix 0.08 0.08

Vitamin premix 0.34 0.34

Stay –C 35% 0.02 0.02

NUTRITION AND GROWTH NUTRITION AND GROWTH [8][8]

The inclusion of soy bean and corn gluten meals for the partial and total replacement of fish meal protein did not generate any adverse effects on the performance of the shrimp (graph shows considerable growth over 18 weeks)

There was a fixed level of poultry by – product meal (16%) and about 71.54% of the fish feed can be derived from plant protein sources. And the fish feed can be rendered free of fish meal.

Component 9% fish meal

0% fish meal

Crude protein 35.7 36.6

Crude fat 8.4 8.4

Crude fiber 2.4 1.9

Ash 8.2 8.1

Calcium 1.3 1.1

Total Phosphorous 1.2 1.3

Lysine 2.0 1.8

Met+Cys 1.1 1.1

% protein from plant sources

54.9 71.5

% protein from animal sources

45.1 28.5

SPIRULINA AS FISH FEED FOR SPIRULINA AS FISH FEED FOR MARINE AND FRESH WATER FISHMARINE AND FRESH WATER FISH

[9][9]

Spirulina based fish feed provides improved colour, slightly better longetivety and lesser incidence of disease [9].

Important trace elements and Essential Amino acids are present [9].

Ingredients of Spirulina fish feed: Spirulina, brine shrimp, squid, krill, mussel, gel binder, plankton, krill meat, krill hydrolysate, lecithin, fish oil, casein, astaxanthin.Vitamins: potassium ascorbate, beta-carotene, biotin, hydroxocobalamin (source of vitamin B12), niacin, riboflavin, thiamin HCL. Amino acids: methionine (dl-methionine), L-Lysine, taurine. Trace elements: calcium chloride, potassium iodide, ferrous sulfate, manganese sulfate, magnesium carbonate and zinc sulfate[9].

Parameter Amount

Protein 55 – 70%

Carbohydrate 15 – 25%

Fats 6 – 8%

Minerals 6 – 13%

Fiber 8 – 10%

Parameter Amount

Min.Crude protein 40%

Min.Crude fat 6%

Max.Crude fiber 2%

Max Moisture 8%

Nutrient content of Spirulina[9]

Nutrient content of fish feed[9]

APPLICATION OF MICROBIAL APPLICATION OF MICROBIAL PHYTASE IN FISH FEEDPHYTASE IN FISH FEED[10][10]

Phytate-rich plant ingredients have restrict the bioavailability of Phosphorous and other minerals leading to increase in discharge into marine environment[10].

Studies have shown that supplemental phytase enzyme

can improve the digestibility and bio-availability of Phosphorous, nitrogen and other minerals, decrease the amount of inorganic-Phosphorous supplement to increase growth and bone mineralization, and noticeably reduce Phosphorous load to marine environment[10].

However, the optimum doses for phytase to replace inorganic Phosphorous have not been evaluated in fish diets[10].

Hence, further research on phytase application in fish feed is largely required. The use of phytase in fish feed will expand along with the need of cost-effective feed and increasing environmental protection concerns[10]. Phytase molecule

(e)

CONCLUSIONCONCLUSION

Research is moving ahead at a faster rate and plant proteins are being used to replace the fish meal in fish feed. However challenges related to production, economics and product quality may exist[11].

The use of plant protein sources lead to low production costs and this is a boon to the farmers as they can increase their profit margins.

Further research is required to evaluate the contribution and composition of plant proteins to fish feed. Plant protein require processing due to the presence of anti – nutritional compounds which act as defence mechanisms. These compounds need to be destroyed as they could harm the fish[4].

Hence, fish meal will no longer be the primary source of protein in aqua feed for carnivorous fish. Fish meal would rather be a specialty ingredient which would be added for increased palatability and balance dietary amino acids as well as supply other essential nutrients and biologically active compounds in order to enhance the product quality [11].

REFERENCESREFERENCES [1] Source: FAO FISHERIES CIRCULAR NO. 815 REVISION 8, 1996 [2] Dr Chang. S, (2008), Biotechnology in aquaculture, Lecture Notes. [3] Hsu. R, (2001), Fishing the future: The Need For Aquaculture, actionbioscience.org, Available from URL:

http://www.actionbioscience.org/environment/hsu.html [4] Adelizi.P, (1998), Biotechnology in aquaculture: The future of fish farming, The AgBiotech Infosource, Issue 33. [5] Adapted from National Research Council. 1981. Nutritional Energetics of Domestic Animals and Glossary of Energy Terms.

Washington, D.C.: National Academy Press. Available from Url: http://books.nap.edu/openbook.php?record_id=2115&page=67 [6] Swann.L, Fish Nutrition and feeding, Auburn University, Available from URL: http://aquanic.org/courses/marine/slides/slides.htm [7]Craig.S and Helfrich.L, (2002), Understanding Fish Nutrition, feeds and feeding,Virginia Cooperative extension, Publication 420 –

256 [8] E.A.Amaya et.al., (2007), Replacement of fish meal in practical diets for the Pacific white shrimp (Litopenaeus vannamei) reared under pond conditions, Aquaculture 262 (2007) 393–401 [9] American Aquarium Products, Spirulina Algae as a fish food for marine and fresh water aquaria, Available from URL:

http://www.americanaquariumproducts.com/SpirulinaAlgae.html [10] cao.L et.al, Application of microbial phytase in fish feed, Enzyme and Microbial Technology, Volume 40, Issue 4, 5 March 2007,

Pages 497-507 [11] Aquaculture Europe 08, Utilization of Plant proteins in Fish Diets, Available from URL:

http://www.thefishsite.com/articles/523/utilisation-of-plant-proteins-in-fish-diets (a) Available from URL: http://wendyusuallywanders.files.wordpress.com/2008/04/long_grain_rice.jpg (b) Available from URL: http://www.ogsi.com/images/dynamic/aquaculture.jpg (c) Available from URL: http://www.science.fau.edu/biology/Images/photos/mcdbiosmall.jpg (d) Available from URL: http://www.fis.com/fis/worldnews/images/20227_329x280_72_DPI_0.jpg (e) Available from URL: http://www.ars.usda.gov/is/graphics/photos/jul06/d550-1i.jpg

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