Abstract Earthworms of the species Dendrodrilus subrubicundus were collected from the trickling f... more Abstract Earthworms of the species Dendrodrilus subrubicundus were collected from the trickling filter beds of a domestic sewage works and freeze dried. The resulting ‘worm meal’, which comprised 65% crude protein and 10% lipid, was evaluated as a fish meal replacer, substituting 0, 10, 50 and 100% of the herring meal protein in a semi-synthetic diet for rainbow trout. The experiment was conducted over a period of 50 days during which time the performance of fish fed these four diets was evaluated on the basis of fish growth and feed utilization efficiency. At low levels of dietary inclusion (10% protein replacement) there was no loss in fish performance, at higher levels (50 and 100% protein replacement) a decline in fish performance occurred. During the experimental period, concentrations of Ca, K, Na, Mg and the trace elements Fe, Zn, Mn, Cu, Pb, Co and Cd were monitored in the fish carcass and selected fish tissues. Some evidence of uptake and accumulation of Fe, Zn, Cu, Pb and Cd was noted in fish fed the diet containing the highest dietary inclusion of ‘warm meal’.
Reviews in fisheries science & aquaculture, Jun 13, 2017
Human health and socioeconomic development are intimately tied to food access and food security. ... more Human health and socioeconomic development are intimately tied to food access and food security. In a world capable of producing sufficient food to meet the entire dietary nutrient needs of all its people, income plays a determinant role in dictating who has access to food or not, with under-nutrition and malnutrition still negatively affecting the health and wellbeing of many of the world's poorest nations. This article attempts to compare the role played by fish and fishery products (whether derived from wild capture fisheries or aquaculture) in the diet of the world's poorest and richest nations. The data show that fish and fishery products play an essential role in human nutrition, constituting the major source of dietary animal protein consumed within the Asian region and within many lower income countries within the African region.
Annals of the New York Academy of Sciences, Oct 1, 2008
The ultimate objective of an aquaculture feed manufacturer and aquaculture food supplier is to en... more The ultimate objective of an aquaculture feed manufacturer and aquaculture food supplier is to ensure that the feed or food produced is both safe and wholesome. Reported food safety risks, which may be associated with the use of commercial animal feeds, including compound aquaculture feeds, usually result from the possible presence of unwanted contaminants, either within the feed ingredients used or from the external contamination of the finished feed on prolonged storage. The major animal feed contaminants that have been reported to date have included Salmonellae, mycotoxins, veterinary drug residues, persistent organic pollutants, agricultural and other chemicals (solvent residues, melamine), heavy metals (mercury, lead, cadmium) and excess mineral salts (hexavalent chromium, arsenic, selenium, flourine), and transmissible spongiform encephalopathies. Apart from the direct negative effect of these possible contaminants on the health of the cultured target species, there is a risk that the feed contaminants may be passed along the food chain, via contaminated aquaculture produce, to consumers. In recent years, public concern regarding food safety has increased as a consequence of the increasing prevalence of antibiotic residues, persistent organic pollutants, and chemicals in farmed seafood. The important role played by the Food and Agriculture Organization of the United Nations (FAO) and the Codex Alimentarius Commission in the development of international standards, guidelines, and recommendations to protect the health of consumers and ensure fair practices in the food trade is discussed.
A preliminary investigation of the nutritive value of three terrestrial lumbricid worms for rainb... more A preliminary investigation of the nutritive value of three terrestrial lumbricid worms for rainbow trout. Aquaculture, 35: 187-199. Two experimental feeding trials were conducted with rainbow trout. In the first trial the nutritive value of three terrestrial lumbricid worms, Eisenia foetida, AZZoZobophora and Lumbricus terrestis, was compared with fish fed a commercial trout ration; and in the second trial the nutritive value of freeze-dried E. foetida meal was compared with that of herring meal at three dietary inclusion levels (replacing 0, 50 and 100% herring meal protein) within a semi-synthetic diet. Fish fed frozen A. Zonga and L. terrestis grew as well or better than fish fed the commercial trout pellet. However, fish fed frozen E. foetida, and to a lesser extent the freezedried worm meal, found this worm species to be totally unpalatable, and displayed little or no growth over the experimental test period. Treatment methods are described to improve the palatability and nutritive value of E. foetida for fish.
Use of wild fish and other aquatic organisms as feed in aquaculture-a review of practices and imp... more Use of wild fish and other aquatic organisms as feed in aquaculture-a review of practices and implications in the Asia-Pacific. In M.R. Hasan and M. Halwart (eds). Fish as feed inputs for aquaculture: practices, sustainability and implications. FAO Fisheries and Aquaculture Technical Paper. No. 518. Rome, FAO. pp. 63-127. Summary 64 1. Introduction 66 2. Major trends in Asian aquaculture 67 3. Use of feeds in aquaculture 74 4. Use of fishmeal and fish oil in Asian aquaculture 81 5. Direct use of fish as feed in Asian aquaculture 91 6. Use of live fish as feed in Asian aquaculture 110 7. Use of fish in feeds in Asia-Pacific aquaculture: an overall analysis 111 8. Impacts of fish-based feed inputs in Asia-Pacific aquaculture 112 9. Looking ahead 116 10. Conclusions 119 Acknowledgements 120 References 121 *Coastal provinces of eastern China.
Bulletin of the Japanese Society of Scientific Fisheries, 1982
Bulletin of the Japanese Society of Scientific Fisheries 48(10), 1463-1468 (1982) A Preliminary S... more Bulletin of the Japanese Society of Scientific Fisheries 48(10), 1463-1468 (1982) A Preliminary Study on the Dietary Protein Requirement of Juvenile Snakehead Kok Leong Wee* and Albert GJ Tacon* (Received March 13, 1982) The dietary protein requirement of juvenile ...
The dietary protein requirement of juvenile snakehead Channa micropeltes was investigated by feed... more The dietary protein requirement of juvenile snakehead Channa micropeltes was investigated by feeding eight semipurified diets containing varying levels of dietary protein within a range of 25.5 to 56.5% by weight over a 56-day feeding period at 28•Ž. On the basis of daily weight gain and daily protein deposition these results indicate that the requirement by juvenile snakehead for dietary protein was about 52% of protein in the diet when fish meal is used as the sole protein source. The relationship between dietary protein level and food conversion ratio, protein efficiency ratio, apparent net protein utilisation, apparent protein digesti bility, apparent dry matter digestibility, hepatosomatic index, and gross carcass composition were determined and discussed in relation to other fish species.
The dietary protein requirement of juvenile snakehead Channa micropeltes was in vestigated by fee... more The dietary protein requirement of juvenile snakehead Channa micropeltes was in vestigated by feediung eight semipurified diets containing varying levels of dietary protein within a range of 25.5 to 56.5% by weight over a 56-day feeding period at 28°C. On the basis of daily weight gain and daily protein deposition these results indicate that the requirement by juvenile snakehead for dietary protein was about 52% of protein in the diet when fish meal is used as the sole protein source. The relationship between dietary protein level and food conversion ratio, protein efficiency ratio, apparent net protein utilisation, apparent protein digesti-bility, apparent dry matter digestibility, hepatosomatic index, and gross carcass composition were determined and discussed in relation to other fish species.
Growth performance of hatchery‐reared Spotted Rose Snapper Lutjanus guttatus reared at two cultur... more Growth performance of hatchery‐reared Spotted Rose Snapper Lutjanus guttatus reared at two culture systems were studied, discussed and compared. We stocked 150 juveniles (mean, 124 g) into each of three floating cages and three onshore tanks (3 m3) supplied with seawater of similar temperature (range 23–29°C). Fish were fed twice daily with an extruded diet containing 50% crude protein and 12% crude lipid. The survival rate was above 90%. After 120 d, the mean weight at harvest was 30% greater among fish reared in cages (337 g) versus tanks (255 g). The final feed conversion (1.44 for cages and 1.48 for tanks) differed between the culture systems. Growth in weight was described by the following exponential equations: W = 132.23 e0.0079t, R2 = 0.98 for cages and W = 129.50 e0.0058t, R2 = 0.99 for tanks. The residual sum of squares analysis indicated that these curves were different. The exponents (b) of the length–weight relationship calculated for cages (3.03) versus tanks (3.00) de...
Reviews in Fisheries Science & Aquaculture, 2021
g seaweed and integrated Multi-trophic Aquaculture laboratory, university of new Brunswick, saint... more g seaweed and integrated Multi-trophic Aquaculture laboratory, university of new Brunswick, saint John, new Brunswick, canada; h chopin coastal health solutions inc, saint John, new Brunswick, canada; i longline environment ltd, london, uK; j universidade nova de lisboa, caparica, Portugal; k Division of hydromechanics coastal and Ocean engineering, leichtweiß-institute for hydraulic engineering and water Resources, technische universität Braunschweig,
The paper reviews the endogenous antinutritional factors or antinutrients present within plant fe... more The paper reviews the endogenous antinutritional factors or antinutrients present within plant feedstuffs, and in particular those protein-rich feedstuffs with potential for use as 'fishmeal replacers' within compound aquafeeds. The toxicity of the major antinutritional factors for farmed fish and shrimp are discussed, and information presented concerning the processing and/or biotechnological methods commonly used to destroy or inactivate them.
This study investigated the effects of exogenous enzyme supplementation, specifically phytase and... more This study investigated the effects of exogenous enzyme supplementation, specifically phytase and protease, in fish meal-free and phosphorus-limited diets for juvenile Litopenaeus vannamei through two feeding trials The trials aimed to assess shrimp growth performance and apparent nutrient digestibility simultaneously in a clear-water recirculating tank system (34 ppt, 30°C) employing a continuous feeding regime, with feces being collected on a daily basis throughout the feeding trials. In the first feeding 50-day feeding trial shrimp (3.4 g initial body weight) were fed diets supplemented with phytase (1000 and 2000 FTU/kg) and phytase together with protease (1000 FTU/kg + protease and 2000 FTU/kg + protease), in addition to animals fed a positive control (supplemented inorganic phosphate) and a negative control diet without supplementation. In the second shrimp feeding trial (4.3 g initial body weight), in addition to negative and positive controls, shrimp were fed increasing levels of phytase (1000, 2000, 3000, 4000 and 8000 FTU/kg) over a 42-day experimental period. Both feeding trials showed beneficial effects phytase addition compared to the negative control, with significant improvements (P < 0.05) observed at dietary phytase levels of 2000 FTU/kg and above. Gains were obtained in growth performance (observed weekly growth of 1.46 and 1.86 g/week for shrimp fed the negative control and diet supplemented with 3000 FTU/kg, respectively), and apparent phosphorus digestibility increasing from 41.7% in animals fed the negative control diet to 52.9% in animals fed the 3000 FTU/kg supplemented. Results indicated that phytase supplementation yielded significant improvements in shrimp growth performance and phosphorus digestibility compared to the negative control. Notably, the observed benefits were evident at specific dietary phytase levels. However, the addition of protease supplements did not demonstrate any discernible effects on shrimp performance under the experimental conditions. Overall, these findings underscore the potential of phytase supplementation as a means to enhance nutrient utilization and promote optimal growth in Litopenaeus vannamei. Further investigations are warranted to explore the full range of benefits and mechanisms associated with protease supplementation in shrimp diets.
The use of fish oils by aquaculture is the key impediment on the future growth and sustainability... more The use of fish oils by aquaculture is the key impediment on the future growth and sustainability of the industry. Fish oil, the key provider of health-beneficial omega-3 long-chain polyunsaturated fatty acids, fluctuates drastically in supply and cost, and is extracted unsustainably from world oceans. Resultantly, its persistent use has fueled a heated global debate and sparked a generation of research focus into possible means of reducing the aquaculture industry's dependence on this resource. This chapter introduces the subject of fish oil usage in aquaculture on a global basis, and briefly traces the history of related issues. Accordingly, the major fish species utilized for fish meal and fish oil production are traced and the chemical and nutritional characteristics of fish oils of different origins are provided. The future expected availability of fish oil for aquaculture and the sustainability of the reduction industry are subsequently discussed.
The designations employed and the presentation of material in this information product do not imp... more The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO in preference to others of a similar nature that are not mentioned. The views expressed in this information product are those of the authors and do not necessarily reflect the views of FAO.
Journal of the World Aquaculture Society, Mar 25, 2023
Over the past 20 years, substantial progress has been made in improving feeds and feeding technol... more Over the past 20 years, substantial progress has been made in improving feeds and feeding technologies for most aquaculture species. Notable improvements in feed conversion efficiency (through a better understanding of requirements and improved feed management) and ingredient sustainability (through increased capability to use a wider range of ingredients) have been achieved. While advances have been made in understanding the requirements of many of the main aquaculture species, there is still much to be done in defining requirements, especially for many of the species being farmed in the developing world. Gains in the efficiency of feeds are slowing for developed species, but potential gains are still appreciable for less developed species. There is a growing need to more precisely prescribe the required levels of essential nutrients and various additives in the diet based on age, genotype, environment, and immune status to deliver a “precision nutrition” approach to farming aquaculture species. There is still further need to diversify our ingredient options to provide greater resilience, as the sustainability of different feed ingredient sources, including possible climate change impacts, is becoming a growing issue. There is a growing demand for biocircularity in our feed ingredient supply chains. Ultimately, what is needed to sustain future feed ingredient needs are sustainable sources of cost‐effective protein, some essential amino acid additives, some omega‐3 fatty acid resources, and various minerals and vitamin additives. The increasing use of new and varied resources will ensure that food safety remains an important issue throughout the world. Feed manufacturing has evolved from a simplistic exercise to a highly complex science with state‐of‐the‐art engineering, but its application is not consistent across all sectors, as there is still widespread use of pelleting, mash, and trash fish feeding in the developing world. Similarly, feed management has also dichotomized between the developed and developing world, with a high reliance on manual skilled labor in the developing world, whereas more advanced aquaculture systems are becoming increasingly reliant on automated computer‐controlled feeding systems.
Latin American Journal of Aquatic Research, Feb 28, 2017
Effects of different protein and carbohydrate contents on growth and survival of juveniles of sou... more Effects of different protein and carbohydrate contents on growth and survival of juveniles of southern Chilean freshwater crayfish, Samastacus spinifrons
Abstract Earthworms of the species Dendrodrilus subrubicundus were collected from the trickling f... more Abstract Earthworms of the species Dendrodrilus subrubicundus were collected from the trickling filter beds of a domestic sewage works and freeze dried. The resulting ‘worm meal’, which comprised 65% crude protein and 10% lipid, was evaluated as a fish meal replacer, substituting 0, 10, 50 and 100% of the herring meal protein in a semi-synthetic diet for rainbow trout. The experiment was conducted over a period of 50 days during which time the performance of fish fed these four diets was evaluated on the basis of fish growth and feed utilization efficiency. At low levels of dietary inclusion (10% protein replacement) there was no loss in fish performance, at higher levels (50 and 100% protein replacement) a decline in fish performance occurred. During the experimental period, concentrations of Ca, K, Na, Mg and the trace elements Fe, Zn, Mn, Cu, Pb, Co and Cd were monitored in the fish carcass and selected fish tissues. Some evidence of uptake and accumulation of Fe, Zn, Cu, Pb and Cd was noted in fish fed the diet containing the highest dietary inclusion of ‘warm meal’.
Reviews in fisheries science & aquaculture, Jun 13, 2017
Human health and socioeconomic development are intimately tied to food access and food security. ... more Human health and socioeconomic development are intimately tied to food access and food security. In a world capable of producing sufficient food to meet the entire dietary nutrient needs of all its people, income plays a determinant role in dictating who has access to food or not, with under-nutrition and malnutrition still negatively affecting the health and wellbeing of many of the world's poorest nations. This article attempts to compare the role played by fish and fishery products (whether derived from wild capture fisheries or aquaculture) in the diet of the world's poorest and richest nations. The data show that fish and fishery products play an essential role in human nutrition, constituting the major source of dietary animal protein consumed within the Asian region and within many lower income countries within the African region.
Annals of the New York Academy of Sciences, Oct 1, 2008
The ultimate objective of an aquaculture feed manufacturer and aquaculture food supplier is to en... more The ultimate objective of an aquaculture feed manufacturer and aquaculture food supplier is to ensure that the feed or food produced is both safe and wholesome. Reported food safety risks, which may be associated with the use of commercial animal feeds, including compound aquaculture feeds, usually result from the possible presence of unwanted contaminants, either within the feed ingredients used or from the external contamination of the finished feed on prolonged storage. The major animal feed contaminants that have been reported to date have included Salmonellae, mycotoxins, veterinary drug residues, persistent organic pollutants, agricultural and other chemicals (solvent residues, melamine), heavy metals (mercury, lead, cadmium) and excess mineral salts (hexavalent chromium, arsenic, selenium, flourine), and transmissible spongiform encephalopathies. Apart from the direct negative effect of these possible contaminants on the health of the cultured target species, there is a risk that the feed contaminants may be passed along the food chain, via contaminated aquaculture produce, to consumers. In recent years, public concern regarding food safety has increased as a consequence of the increasing prevalence of antibiotic residues, persistent organic pollutants, and chemicals in farmed seafood. The important role played by the Food and Agriculture Organization of the United Nations (FAO) and the Codex Alimentarius Commission in the development of international standards, guidelines, and recommendations to protect the health of consumers and ensure fair practices in the food trade is discussed.
A preliminary investigation of the nutritive value of three terrestrial lumbricid worms for rainb... more A preliminary investigation of the nutritive value of three terrestrial lumbricid worms for rainbow trout. Aquaculture, 35: 187-199. Two experimental feeding trials were conducted with rainbow trout. In the first trial the nutritive value of three terrestrial lumbricid worms, Eisenia foetida, AZZoZobophora and Lumbricus terrestis, was compared with fish fed a commercial trout ration; and in the second trial the nutritive value of freeze-dried E. foetida meal was compared with that of herring meal at three dietary inclusion levels (replacing 0, 50 and 100% herring meal protein) within a semi-synthetic diet. Fish fed frozen A. Zonga and L. terrestis grew as well or better than fish fed the commercial trout pellet. However, fish fed frozen E. foetida, and to a lesser extent the freezedried worm meal, found this worm species to be totally unpalatable, and displayed little or no growth over the experimental test period. Treatment methods are described to improve the palatability and nutritive value of E. foetida for fish.
Use of wild fish and other aquatic organisms as feed in aquaculture-a review of practices and imp... more Use of wild fish and other aquatic organisms as feed in aquaculture-a review of practices and implications in the Asia-Pacific. In M.R. Hasan and M. Halwart (eds). Fish as feed inputs for aquaculture: practices, sustainability and implications. FAO Fisheries and Aquaculture Technical Paper. No. 518. Rome, FAO. pp. 63-127. Summary 64 1. Introduction 66 2. Major trends in Asian aquaculture 67 3. Use of feeds in aquaculture 74 4. Use of fishmeal and fish oil in Asian aquaculture 81 5. Direct use of fish as feed in Asian aquaculture 91 6. Use of live fish as feed in Asian aquaculture 110 7. Use of fish in feeds in Asia-Pacific aquaculture: an overall analysis 111 8. Impacts of fish-based feed inputs in Asia-Pacific aquaculture 112 9. Looking ahead 116 10. Conclusions 119 Acknowledgements 120 References 121 *Coastal provinces of eastern China.
Bulletin of the Japanese Society of Scientific Fisheries, 1982
Bulletin of the Japanese Society of Scientific Fisheries 48(10), 1463-1468 (1982) A Preliminary S... more Bulletin of the Japanese Society of Scientific Fisheries 48(10), 1463-1468 (1982) A Preliminary Study on the Dietary Protein Requirement of Juvenile Snakehead Kok Leong Wee* and Albert GJ Tacon* (Received March 13, 1982) The dietary protein requirement of juvenile ...
The dietary protein requirement of juvenile snakehead Channa micropeltes was investigated by feed... more The dietary protein requirement of juvenile snakehead Channa micropeltes was investigated by feeding eight semipurified diets containing varying levels of dietary protein within a range of 25.5 to 56.5% by weight over a 56-day feeding period at 28•Ž. On the basis of daily weight gain and daily protein deposition these results indicate that the requirement by juvenile snakehead for dietary protein was about 52% of protein in the diet when fish meal is used as the sole protein source. The relationship between dietary protein level and food conversion ratio, protein efficiency ratio, apparent net protein utilisation, apparent protein digesti bility, apparent dry matter digestibility, hepatosomatic index, and gross carcass composition were determined and discussed in relation to other fish species.
The dietary protein requirement of juvenile snakehead Channa micropeltes was in vestigated by fee... more The dietary protein requirement of juvenile snakehead Channa micropeltes was in vestigated by feediung eight semipurified diets containing varying levels of dietary protein within a range of 25.5 to 56.5% by weight over a 56-day feeding period at 28°C. On the basis of daily weight gain and daily protein deposition these results indicate that the requirement by juvenile snakehead for dietary protein was about 52% of protein in the diet when fish meal is used as the sole protein source. The relationship between dietary protein level and food conversion ratio, protein efficiency ratio, apparent net protein utilisation, apparent protein digesti-bility, apparent dry matter digestibility, hepatosomatic index, and gross carcass composition were determined and discussed in relation to other fish species.
Growth performance of hatchery‐reared Spotted Rose Snapper Lutjanus guttatus reared at two cultur... more Growth performance of hatchery‐reared Spotted Rose Snapper Lutjanus guttatus reared at two culture systems were studied, discussed and compared. We stocked 150 juveniles (mean, 124 g) into each of three floating cages and three onshore tanks (3 m3) supplied with seawater of similar temperature (range 23–29°C). Fish were fed twice daily with an extruded diet containing 50% crude protein and 12% crude lipid. The survival rate was above 90%. After 120 d, the mean weight at harvest was 30% greater among fish reared in cages (337 g) versus tanks (255 g). The final feed conversion (1.44 for cages and 1.48 for tanks) differed between the culture systems. Growth in weight was described by the following exponential equations: W = 132.23 e0.0079t, R2 = 0.98 for cages and W = 129.50 e0.0058t, R2 = 0.99 for tanks. The residual sum of squares analysis indicated that these curves were different. The exponents (b) of the length–weight relationship calculated for cages (3.03) versus tanks (3.00) de...
Reviews in Fisheries Science & Aquaculture, 2021
g seaweed and integrated Multi-trophic Aquaculture laboratory, university of new Brunswick, saint... more g seaweed and integrated Multi-trophic Aquaculture laboratory, university of new Brunswick, saint John, new Brunswick, canada; h chopin coastal health solutions inc, saint John, new Brunswick, canada; i longline environment ltd, london, uK; j universidade nova de lisboa, caparica, Portugal; k Division of hydromechanics coastal and Ocean engineering, leichtweiß-institute for hydraulic engineering and water Resources, technische universität Braunschweig,
The paper reviews the endogenous antinutritional factors or antinutrients present within plant fe... more The paper reviews the endogenous antinutritional factors or antinutrients present within plant feedstuffs, and in particular those protein-rich feedstuffs with potential for use as 'fishmeal replacers' within compound aquafeeds. The toxicity of the major antinutritional factors for farmed fish and shrimp are discussed, and information presented concerning the processing and/or biotechnological methods commonly used to destroy or inactivate them.
This study investigated the effects of exogenous enzyme supplementation, specifically phytase and... more This study investigated the effects of exogenous enzyme supplementation, specifically phytase and protease, in fish meal-free and phosphorus-limited diets for juvenile Litopenaeus vannamei through two feeding trials The trials aimed to assess shrimp growth performance and apparent nutrient digestibility simultaneously in a clear-water recirculating tank system (34 ppt, 30°C) employing a continuous feeding regime, with feces being collected on a daily basis throughout the feeding trials. In the first feeding 50-day feeding trial shrimp (3.4 g initial body weight) were fed diets supplemented with phytase (1000 and 2000 FTU/kg) and phytase together with protease (1000 FTU/kg + protease and 2000 FTU/kg + protease), in addition to animals fed a positive control (supplemented inorganic phosphate) and a negative control diet without supplementation. In the second shrimp feeding trial (4.3 g initial body weight), in addition to negative and positive controls, shrimp were fed increasing levels of phytase (1000, 2000, 3000, 4000 and 8000 FTU/kg) over a 42-day experimental period. Both feeding trials showed beneficial effects phytase addition compared to the negative control, with significant improvements (P < 0.05) observed at dietary phytase levels of 2000 FTU/kg and above. Gains were obtained in growth performance (observed weekly growth of 1.46 and 1.86 g/week for shrimp fed the negative control and diet supplemented with 3000 FTU/kg, respectively), and apparent phosphorus digestibility increasing from 41.7% in animals fed the negative control diet to 52.9% in animals fed the 3000 FTU/kg supplemented. Results indicated that phytase supplementation yielded significant improvements in shrimp growth performance and phosphorus digestibility compared to the negative control. Notably, the observed benefits were evident at specific dietary phytase levels. However, the addition of protease supplements did not demonstrate any discernible effects on shrimp performance under the experimental conditions. Overall, these findings underscore the potential of phytase supplementation as a means to enhance nutrient utilization and promote optimal growth in Litopenaeus vannamei. Further investigations are warranted to explore the full range of benefits and mechanisms associated with protease supplementation in shrimp diets.
The use of fish oils by aquaculture is the key impediment on the future growth and sustainability... more The use of fish oils by aquaculture is the key impediment on the future growth and sustainability of the industry. Fish oil, the key provider of health-beneficial omega-3 long-chain polyunsaturated fatty acids, fluctuates drastically in supply and cost, and is extracted unsustainably from world oceans. Resultantly, its persistent use has fueled a heated global debate and sparked a generation of research focus into possible means of reducing the aquaculture industry's dependence on this resource. This chapter introduces the subject of fish oil usage in aquaculture on a global basis, and briefly traces the history of related issues. Accordingly, the major fish species utilized for fish meal and fish oil production are traced and the chemical and nutritional characteristics of fish oils of different origins are provided. The future expected availability of fish oil for aquaculture and the sustainability of the reduction industry are subsequently discussed.
The designations employed and the presentation of material in this information product do not imp... more The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO in preference to others of a similar nature that are not mentioned. The views expressed in this information product are those of the authors and do not necessarily reflect the views of FAO.
Journal of the World Aquaculture Society, Mar 25, 2023
Over the past 20 years, substantial progress has been made in improving feeds and feeding technol... more Over the past 20 years, substantial progress has been made in improving feeds and feeding technologies for most aquaculture species. Notable improvements in feed conversion efficiency (through a better understanding of requirements and improved feed management) and ingredient sustainability (through increased capability to use a wider range of ingredients) have been achieved. While advances have been made in understanding the requirements of many of the main aquaculture species, there is still much to be done in defining requirements, especially for many of the species being farmed in the developing world. Gains in the efficiency of feeds are slowing for developed species, but potential gains are still appreciable for less developed species. There is a growing need to more precisely prescribe the required levels of essential nutrients and various additives in the diet based on age, genotype, environment, and immune status to deliver a “precision nutrition” approach to farming aquaculture species. There is still further need to diversify our ingredient options to provide greater resilience, as the sustainability of different feed ingredient sources, including possible climate change impacts, is becoming a growing issue. There is a growing demand for biocircularity in our feed ingredient supply chains. Ultimately, what is needed to sustain future feed ingredient needs are sustainable sources of cost‐effective protein, some essential amino acid additives, some omega‐3 fatty acid resources, and various minerals and vitamin additives. The increasing use of new and varied resources will ensure that food safety remains an important issue throughout the world. Feed manufacturing has evolved from a simplistic exercise to a highly complex science with state‐of‐the‐art engineering, but its application is not consistent across all sectors, as there is still widespread use of pelleting, mash, and trash fish feeding in the developing world. Similarly, feed management has also dichotomized between the developed and developing world, with a high reliance on manual skilled labor in the developing world, whereas more advanced aquaculture systems are becoming increasingly reliant on automated computer‐controlled feeding systems.
Latin American Journal of Aquatic Research, Feb 28, 2017
Effects of different protein and carbohydrate contents on growth and survival of juveniles of sou... more Effects of different protein and carbohydrate contents on growth and survival of juveniles of southern Chilean freshwater crayfish, Samastacus spinifrons
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