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Simon Davies
Fish Nutrition and Aquaculture Group, Department of Animal Production, Welfare and Veterinary Sciences, Harper Adams University, Newport TF10 8NB, United Kingdom

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Journal article
Published: 17 May 2020 in Aquaculture
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Efficiency assessments of marine ingredient use in aquaculture are required to fully understand their contribution to global seafood supply and their impacts on all UN Sustainable Development Goals. Fish In: Fish Out (FIFO) ratios have become the principal metric used to ensure aquaculture does not negatively impact wild fish stocks. However, several approaches have been advocated to calculate the FIFO ratio and there have been criticisms that the different approaches employed lead to over- or under- estimates of the dependence of aquaculture on marine ingredients. Critically, FIFO does not align with Life Cycle Assessment as a measure of other environmental impacts. In this paper we present an alternative method to calculate the FIFO ratio based on the principle of economic allocation (economic Fish In: Fish Out – eFIFO) as commonly used in Life Cycle Assessments. Economic allocation acts as a proxy for the nutritional value of ingredients and places higher importance on the more limiting co-products generated and their relative demand. Substitution of marine ingredients by alternate feed ingredients has significantly reduced the amount of fishmeal and fish oil in aquafeed formulations for most farmed fish species, resulting in a continually decreasing FIFO ratio. Results show that most aquaculture species groups assessed in this study are net producers of fish, while salmon and trout aquaculture are net neutral, producing as much fish biomass as is consumed. Overall, global fed-aquaculture currently produces three to four times as much fish as it consumes. Tracking historical prices of fish oil against fishmeal, the relative higher price of fish oil leads to relatively higher allocation of fish to fish oil compared to fishmeal. This leads to relatively higher eFIFO for species with high fish oil requirements.

ACS Style

Björn Kok; Wesley Malcorps; Michael F. Tlusty; Mahmoud Eltholth; Neil A. Auchterlonie; David C. Little; Robert Harmsen; Richard W. Newton; Simon J. Davies. Fish as feed: Using economic allocation to quantify the Fish In : Fish Out ratio of major fed aquaculture species. Aquaculture 2020, 528, 735474 .

AMA Style

Björn Kok, Wesley Malcorps, Michael F. Tlusty, Mahmoud Eltholth, Neil A. Auchterlonie, David C. Little, Robert Harmsen, Richard W. Newton, Simon J. Davies. Fish as feed: Using economic allocation to quantify the Fish In : Fish Out ratio of major fed aquaculture species. Aquaculture. 2020; 528 ():735474.

Chicago/Turabian Style

Björn Kok; Wesley Malcorps; Michael F. Tlusty; Mahmoud Eltholth; Neil A. Auchterlonie; David C. Little; Robert Harmsen; Richard W. Newton; Simon J. Davies. 2020. "Fish as feed: Using economic allocation to quantify the Fish In : Fish Out ratio of major fed aquaculture species." Aquaculture 528, no. : 735474.

Journal article
Published: 25 February 2019 in Sustainability
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Aquaculture is central in meeting expanding global demands for shrimp consumption. Consequently, increasing feed use is mainly responsible for the overall environmental impact of aquaculture production. Significant amounts of fishmeal are included in shrimp diets, causing dependency on finite marine resources. Driven by economic incentives, terrestrial plant ingredients are widely viewed as sustainable alternatives. Incremental fishmeal substitution by plant ingredients in shrimp feed was modeled and effects on marine and terrestrial resources such as fish, land, freshwater, nitrogen, and phosphorus were assessed. We find that complete substitution of 20–30% fishmeal totals could lead to increasing demand for freshwater (up to 63%), land (up to 81%), and phosphorus (up to 83%), while other substitution rates lead to proportionally lower impacts. These findings suggest additional pressures on essential agricultural resources with associated socio-economic and environmental effects as a trade-off to pressures on finite marine resources. Even though the production of shrimp feed (or aquafeed in general) utilizes only a small percentage of the global crop production, the findings indicate that the sustainability of substituting fishmeal by plant ingredients should not be taken for granted, especially since aquaculture has been one of the fastest growing food sectors. Therefore, the importance of utilizing by-products and novel ingredients such as microbial biomass, algae, and insect meals in mitigating the use of marine and terrestrial resources is discussed.

ACS Style

Wesley Malcorps; Björn Kok; Mike Van‘T Land; Maarten Fritz; Davy Van Doren; Kurt Servin; Paul Van Der Heijden; Roy Palmer; Neil Auchterlonie; Max Rietkerk; Maria Santos; Simon Davies. The Sustainability Conundrum of Fishmeal Substitution by Plant Ingredients in Shrimp Feeds. Sustainability 2019, 11, 1212 .

AMA Style

Wesley Malcorps, Björn Kok, Mike Van‘T Land, Maarten Fritz, Davy Van Doren, Kurt Servin, Paul Van Der Heijden, Roy Palmer, Neil Auchterlonie, Max Rietkerk, Maria Santos, Simon Davies. The Sustainability Conundrum of Fishmeal Substitution by Plant Ingredients in Shrimp Feeds. Sustainability. 2019; 11 (4):1212.

Chicago/Turabian Style

Wesley Malcorps; Björn Kok; Mike Van‘T Land; Maarten Fritz; Davy Van Doren; Kurt Servin; Paul Van Der Heijden; Roy Palmer; Neil Auchterlonie; Max Rietkerk; Maria Santos; Simon Davies. 2019. "The Sustainability Conundrum of Fishmeal Substitution by Plant Ingredients in Shrimp Feeds." Sustainability 11, no. 4: 1212.

Original article
Published: 18 November 2018 in Aquaculture Nutrition
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Experimental diets were formulated to evaluate a “pure” poultry meat meal (PMM) source in diets formulated for juvenile gilthead sea bream (Sparus aurata L.). The digestible protein contribution of fish meal in a control diet was substituted by 25%, 50% and 75% of a processed poultry meat meal (PMM) on a digestible crude protein (DCP) basis and by 5% and 10% for an enzyme‐treated feather meal (EFM) and also a spray‐dried haemaglobin meal (SDHM), respectively. In a consecutive trial, diets were designed to assess the value of a “pure” (defatted) poultry protein substituting the fish meal (FM) protein content. Experimental diets included: a control diet, two test diets where 75% of FM was replaced by a full‐fat PMM (PMM75) or a defatted grade of PMM (dPMM75) and two test diets where 50% of FM was substituted for defatted PMM (dPMM50) or a 50:50 blend of soya bean meal and defatted PMM (SBM/dPMM) to produce a composite product. This soya bean/dPMM blend was tested to enhance the nutritional value of this key plant ingredient commonly employed in sea bream diets that can be deficient in specific amino acids and minerals. In the first trial, gilthead sea bream grew effectively on diets containing up to the 75% replacement of FM attaining a mean weight of 63.6 g compared to 67.8 g for the FM control fed group. For the consecutive trial, the fishmeal‐based control diet yielded the highest SGR followed by dPMM50 and SBM/dPMM blend inclusion but was not significant. Carcass FA profiles of gilthead sea bream conformed to the expected changes in relation to the dietary FA patterns, with the 18:1n‐9 representative of the poultry lipid signature becoming more apparent with PMM inclusion. The ratio of n‐3/n‐6 fatty acids was greatly affected in sea bream fed the full‐fat PMM at 75% inclusion due to fish oil exclusion. Defatted dPMM, however, allowed more of the fish oil to be used in the diet and reducing this latter effect in sea bream carcass, hence restoring the higher total omega‐3 HUFA fatty acids namely EPA and DHA and n‐3/n‐6 ratio. It is concluded that poultry meat meal can be modestly incorporated into formulated diets for sea bream and can be used in conjunction with soya bean meal without any fundamental changes in performance and feed efficiency.

ACS Style

Simon J. Davies; Jerome Laporte; Antonio Gouveia; Heba S. Salim; Stephen M. Woodgate; Mohamed S. Hassaan; Ehab R. El-Haroun. Validation of processed animal proteins (mono-PAPS) in experimental diets for juvenile gilthead sea bream (Sparus aurata L.) as primary fish meal replacers within a European perspective. Aquaculture Nutrition 2018, 25, 225 -238.

AMA Style

Simon J. Davies, Jerome Laporte, Antonio Gouveia, Heba S. Salim, Stephen M. Woodgate, Mohamed S. Hassaan, Ehab R. El-Haroun. Validation of processed animal proteins (mono-PAPS) in experimental diets for juvenile gilthead sea bream (Sparus aurata L.) as primary fish meal replacers within a European perspective. Aquaculture Nutrition. 2018; 25 (1):225-238.

Chicago/Turabian Style

Simon J. Davies; Jerome Laporte; Antonio Gouveia; Heba S. Salim; Stephen M. Woodgate; Mohamed S. Hassaan; Ehab R. El-Haroun. 2018. "Validation of processed animal proteins (mono-PAPS) in experimental diets for juvenile gilthead sea bream (Sparus aurata L.) as primary fish meal replacers within a European perspective." Aquaculture Nutrition 25, no. 1: 225-238.

Original article
Published: 29 May 2018 in Aquaculture Nutrition
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Nile tilapia, Oreochromis niloticus (average initial weight, 5.91 ± 0.04 g), were fed four isonitrogenous and isolipidic diets for 84 days. The diets contained four levels of yeast extract (CW‐I) rich in nucleotides and β‐glucan: 0 (control), 5, 10 and 15 g/kg diet. Weight gain increased linearly, whereas the feed conversion ratio decreased linearly with increasing levels of yeast extract. The diet containing 15 g/kg yeast extract resulted in significantly better (p < 0.05) specific growth rates and protein efficiency ratios. No significant (p > 0.05) differences were found in dry matter, protein, lipid or ash contents or in haematocrit, haemoglobin or total protein contents among the treatment groups. Blood sample profiles showed an increase in white and red blood cells in fish fed 15 g/kg yeast extract in comparison with the other treatment groups. The fish fed the diets with 10 and 15 g/kg yeast extract had significantly higher albumin and globulin levels than the control group, whereas decreased levels of cholesterol and triglycerides, aspartate aminotransferase and alanine aminotransferase were noted in fish fed the diet with 15 g/kg yeast extract. Histological analysis of the liver and intestine in fish fed the control diet showed a slightly abnormal structure in these organs. Only in fish fed diets supplemented with the highest amount of yeast extract was the structure of the hepatocytes and villi almost unchanged, which indicated that the yeast nucleotides could improve hepatic function and promote liver and gut restoration.

ACS Style

Mohamed S. Hassaan; Soaad A. Mahmoud; Sylwia Jarmolowicz; Ehab R. El‐Haroun; Eman Y. Mohammady; Simon J. Davies. Effects of dietary baker’s yeast extract on the growth, blood indices and histology of Nile tilapia (Oreochromis niloticusL.) fingerlings. Aquaculture Nutrition 2018, 24, 1709 -1717.

AMA Style

Mohamed S. Hassaan, Soaad A. Mahmoud, Sylwia Jarmolowicz, Ehab R. El‐Haroun, Eman Y. Mohammady, Simon J. Davies. Effects of dietary baker’s yeast extract on the growth, blood indices and histology of Nile tilapia (Oreochromis niloticusL.) fingerlings. Aquaculture Nutrition. 2018; 24 (6):1709-1717.

Chicago/Turabian Style

Mohamed S. Hassaan; Soaad A. Mahmoud; Sylwia Jarmolowicz; Ehab R. El‐Haroun; Eman Y. Mohammady; Simon J. Davies. 2018. "Effects of dietary baker’s yeast extract on the growth, blood indices and histology of Nile tilapia (Oreochromis niloticusL.) fingerlings." Aquaculture Nutrition 24, no. 6: 1709-1717.

Article
Published: 12 October 2017 in Aquaculture International
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The present study was carried out to evaluate the effect of supplementation of Garlen®, Diamond V XPC®, and Bactozyme® and their combination in the diets of European sea bass, Dicentrarchus labrax larvae development in hatcheries on feed intake, growth performance, feed efficiency, intestinal bacterial, survival rate, and economics analysis. Dicentrarchus labrax juveniles (1.4 ± 0.5 mg) were distributed into eight experimental groups with a density of 2.5 larvae per liter. Eight iso-nitrogenous (55% crude protein) and iso-caloric (19.2 ± 0.2 MJ/kg, DM) weaning diets were formulated to contain the control diet (no feed additives), individually or mixed alternatively with three feed additives (Garlen®; Diamond V XPC®, and Bactozyme®). Each experimental diet was allocated to three tanks of fish and fed for 12 weeks. Growth and survival rate (S %) were improved for larvae fed the diets supplied with either (Diamond V XPC® + Bactozyme®) or (Garlen® + Diamond V XPC® + Bactozyme®), respectively compared to the control larvae group. The best FCR value was recorded for larvae fed a diet supply with (Garlen® + Diamond V XPC® + Bactozyme®), while the control larvae group recorded the worst FCR. The optimum significant (P ≤ 0.05) nutrient utilization values, larvae body crude protein content, activity test (ATV%), and profit index (PI) values were observed for larvae fed a diet containing Diamond V XPC® + Bactozyme® or Garlen® + Diamond V XPC + Bactozyme® compared to other treatments. The opposite trend was observed for total bacterial (TBC) and Vibrio sp. counts. No significant (P ≥ 0.01) difference was recorded in Aeromonas sp. count values in all experimental treatments. The results from this study show that (Garlen®; Diamond V XPC®, and Bactozyme®) individually or mixed alternately as growth promoters and immune stimulants in early weaning larval diets of European sea bass under hatchery conditions led to improve growth performance, feed utilization, survival, lowest intestinal bacterial load, and highest profit index (LE).

ACS Style

Ashraf Goda; E. A. Omar; T. M. Srour; A. M. Kotiet; Ehab El-Haroun; Simon J. Davies. Effect of diets supplemented with feed additives on growth, feed utilization, survival, body composition and intestinal bacterial load of early weaning European seabass, Dicentrarchus labrax post-larvae. Aquaculture International 2017, 26, 169 -183.

AMA Style

Ashraf Goda, E. A. Omar, T. M. Srour, A. M. Kotiet, Ehab El-Haroun, Simon J. Davies. Effect of diets supplemented with feed additives on growth, feed utilization, survival, body composition and intestinal bacterial load of early weaning European seabass, Dicentrarchus labrax post-larvae. Aquaculture International. 2017; 26 (1):169-183.

Chicago/Turabian Style

Ashraf Goda; E. A. Omar; T. M. Srour; A. M. Kotiet; Ehab El-Haroun; Simon J. Davies. 2017. "Effect of diets supplemented with feed additives on growth, feed utilization, survival, body composition and intestinal bacterial load of early weaning European seabass, Dicentrarchus labrax post-larvae." Aquaculture International 26, no. 1: 169-183.