Hermetia illucens and Poultry by-Product Meals as Alternatives to Plant Protein Sources in Gilthead Seabream (Sparus aurata) Diet: A Multidisciplinary Study on Fish Gut Status

The attempt to replace marine-derived ingredients for aquafeed formulation with plant-derived ones has met some limitations due to their negative side effects on many fish species. In this context, finding new, sustainable ingredients able to promote fish welfare is currently under exploration. In the present study, poultry by-products and Hermetia illucens meal were used to replace the vegetable protein fraction in diets totally deprived of fish meal intended for gilthead seabream (Sparus aurata). After a 12-week feeding trial, a multidisciplinary approach including histological, molecular, and spectroscopic techniques was adopted to investigate intestine and liver responses to the different dietary formulations. Regardless of the alternative ingredient used, the reduction in dietary vegetable proteins resulted in a lower incidence of intestine histological alterations and inflammatory responses. In addition, the dietary inclusion of insect meal positively affected the reduction in the molecular inflammatory markers analyzed. Spectroscopic analyses showed that poultry by-product meal improved lipid absorption in the intestine, while insect meal induced increased liver lipid deposition in fish. The results obtained demonstrated that both poultry by-products and H. illucens meal can successfully be used to replace plant-derived ingredients in diets for gilthead seabream, promoting healthy aquaculture.

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Dietary supplementation with Gracilaria sp. by-products modulates stress response, antioxidant and immune systems of gilthead seabream (Sparus aurata) exposed to crowding

Journal of Applied Phycology ◽

10.1007/s10811-020-02268-0 ◽

2020 ◽

Vol 32 (6) ◽

pp. 4347-4359

Author(s):

Francisca Silva-Brito ◽

Francisco A. Guardiola ◽

Thaís Cavalheri ◽

Rui Pereira ◽

Helena Abreu ◽

...

Keyword(s):

Stress Response ◽

Sparus Aurata ◽

Dietary Supplementation ◽

Gilthead Seabream ◽

Immune Systems ◽

By Products

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Application of laboratory methods for understanding fish responses to black soldier fly (Hermetia illucens) based diets

Journal of Insects as Food and Feed ◽

10.3920/jiff2020.0135 ◽

2021 ◽

pp. 1-24

Author(s):

M. Zarantoniello ◽

B. Randazzo ◽

G. Secci ◽

V. Notarstefano ◽

E. Giorgini ◽

...

Keyword(s):

Experimental Models ◽

Research Field ◽

Fish Welfare ◽

Fish Oil Replacement ◽

Laboratory Methods ◽

Black Soldier Fly ◽

Hermetia Illucens ◽

Physico Chemical ◽

Methodological Approaches ◽

By Products

A major challenge for development of sustainable aquafeeds is its dependence on fish meal and fish oil. Replacement with more sustainable, nutritious and safe ingredients is now a priority. Over the last years, among several alternatives proposed, insects have received great attention as possible candidates. In particular, the black soldier fly (Hermetia illucens; BSF) represents a concrete example of how the circular economy concept can be applied to fish culture, providing a valuable biomass rich in fat and protein valorising organic by-products. In the last decade, several studies have been published about the use of different BSF dietary inclusion levels for various fish species including experimental models. Varying and encouraging results have been obtained in this research field using a plethora of laboratory methodological approaches that can be applied and coupled to obtain a comprehensive view of the BSF-based diets effects on fish physiology, health, and quality. The present review aims to explore some of the most promising laboratory approaches like histology, infrared spectroscopy, gut microbiome sequencing, molecular biology, fish fillets’ physico-chemical and sensory properties, essential for a better understanding of fish welfare and fillet quality, when BSF is used as aquafeed ingredient. In particular, great importance has been given to European finfish species and experimental models.

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Mediterranean Aquaculture in a Changing Climate: Temperature Effects on Pathogens and Diseases of Three Farmed Fish Species

Pathogens ◽

10.3390/pathogens10091205 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1205

Author(s):

Maria Chiara Cascarano ◽

Orestis Stavrakidis-Zachou ◽

Ivona Mladineo ◽

Kim D. Thompson ◽

Nikos Papandroulakis ◽

...

Keyword(s):

Climate Change ◽

Mediterranean Sea ◽

Fish Species ◽

Sparus Aurata ◽

Dicentrarchus Labrax ◽

Disease Outbreaks ◽

Gilthead Seabream ◽

Farmed Fish ◽

Fish Welfare ◽

The Mediterranean

Climate change is expected to have a drastic effect on aquaculture worldwide. As we move forward with the agenda to increase and diversify aquaculture production, rising temperatures will have a progressively relevant impact on fish farming, linked to a multitude of issues associated with fish welfare. Temperature affects the physiology of both fish and pathogens, and has the potential to lead to significant increases in disease outbreaks within aquaculture systems, resulting in severe financial impacts. Significant shifts in future temperature regimes are projected for the Mediterranean Sea. We therefore aim to review and discuss the existing knowledge relating to disease outbreaks in the context of climate change in Mediterranean finfish aquaculture. The objective is to describe the effects of temperature on the physiology of both fish and pathogens, and moreover to list and discuss the principal diseases of the three main fish species farmed in the Mediterranean, namely gilthead seabream (Sparus aurata), European seabass (Dicentrarchus labrax), and meagre (Argyrosomus regius). We will attempt to link the pathology of each disease to a specific temperature range, while discussing potential future disease threats associated with the available climate change trends for the Mediterranean Sea.

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Phenylalanine and Tyrosine as Feed Additives for Reducing Stress and Enhancing Welfare in Gilthead Seabream and Meagre

Animals ◽

10.3390/ani11010045 ◽

2020 ◽

Vol 11 (1) ◽

pp. 45

Author(s):

Natalia Salamanca ◽

Inmaculada Giráldez ◽

Emilio Morales ◽

Ignacio de La Rosa ◽

Marcelino Herrera

Keyword(s):

Amino Acids ◽

Sparus Aurata ◽

Control Diet ◽

Feed Additives ◽

Food Supplementation ◽

Gilthead Seabream ◽

Fish Welfare ◽

Air Exposure ◽

Stress Markers ◽

Interspecific Differences

Increased aquaculture production is associated with a growing interest in improving fish welfare. For this reason, the search for strategies to mitigate stress has intensified, one of these strategies being food supplementation with amino acids. The objective of this study was to evaluate the effects of dietary phenylalanine (Phe) and Tyrosine (Tyr) on the stress response and metabolism of juvenile gilthead seabreams (Sparus aurata) and meagres (Argyrosomus regius). Fish batches were fed a control diet and two diets supplemented with 5% Phe or Tyr for seven days. At the end of the experiment fish were stressed by air exposure for 3 min and then sacrificed for the extraction of blood and brain. Classical plasma stress markers were analyzed (glucose, lactate, proteins, cortisol), as well as hormones derived from those amino acids (adrenaline, noradrenaline and dopamine). Despite interspecific differences, fish fed the diets supplemented with Phe or Tyr showed a reduction on several stress markers. However, interspecific differences were detected for many indicators. Concretely, hormonal stress markers were significantly attenuated in meagres fed the enriched diets. Moreover, the stress condition favored a mobilization of amino acids towards the brain, especially in supplemented diets, hence this amino acid excess could be used as an energy substrate to cope with stress.

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Apparent digestibility coefficients of brewer's by-products used in feeds for rainbow trout (Oncorhynchus mykiss) and gilthead seabream (Sparus aurata)

Aquaculture ◽

10.1016/j.aquaculture.2020.735796 ◽

2021 ◽

Vol 530 ◽

pp. 735796

Author(s):

J. Nazzaro ◽

D. San Martin ◽

A.M. Perez-Vendrell ◽

L. Padrell ◽

B. Iñarra ◽

...

Keyword(s):

Rainbow Trout ◽

Oncorhynchus Mykiss ◽

Sparus Aurata ◽

Gilthead Seabream ◽

Apparent Digestibility ◽

Rainbow Trout Oncorhynchus Mykiss ◽

By Products

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Brewery by-products (yeast and spent grain) as protein sources in gilthead seabream (Sparus aurata) feeds

Aquaculture ◽

10.1016/j.aquaculture.2021.736921 ◽

2021 ◽

pp. 736921

Author(s):

A. Estévez ◽

L. Padrell ◽

B. Iñarra ◽

M. Orive ◽

D. San Martin

Keyword(s):

Sparus Aurata ◽

Gilthead Seabream ◽

Protein Sources ◽

Spent Grain ◽

By Products

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Protein changes as robust signatures of fish chronic stress: a proteomics approach in fish welfare research

10.21203/rs.2.20027/v1 ◽

2020 ◽

Author(s):

Cláudia Raposo de Magalhães ◽

Denise Schrama ◽

Ana Paula Farinha ◽

Dominique Revets ◽

Annette Kuehn ◽

...

Keyword(s):

Chronic Stress ◽

Sparus Aurata ◽

Physiological Adaptation ◽

Spectrometric Analysis ◽

Gilthead Seabream ◽

Stress Monitoring ◽

Fish Welfare ◽

Protein Protein Interaction ◽

Glucose Levels ◽

Proteomics Approach

Abstract Background In the verge of getting a greater understanding of fish welfare, sensitive technological tools, such as proteomics, may assist the aquaculture industry as it allows an unbiased approach for the discovery of potential biomarkers for stress monitoring. Stress is characterized by a cascade of physiological responses that end-up inducing further changes at the whole-animal level that might either increase fitness or impair welfare. Monitorization of this dynamic process, up till now relies on indicators that are only a snapshot of the stress level experienced. Within this scope, using gilthead seabream ( Sparus aurata ) as a model, three chronic stress conditions, namely overcrowding, handling and hypoxia, were employed to evaluate the potential of the fish protein-based adaptations as reliable signatures of chronic stress, in contrast with the commonly used indicators of primary and secondary stress responses.Results A large spectrum of biological variation regarding cortisol and glucose levels was observed, which values rose higher in net handled fish. In this sense, a potential pattern of stressor-specificity was evidenced since the magnitude of response and tolerance varied markedly from a permanent (crowding) to a repetitive stressor (handling). Gel-based proteomics analysis of the plasma proteome also revealed that net handled fish had the highest number of proteins with significantly altered abundance, compared to the other trials, whereas mass spectrometric analysis, followed by gene ontology enrichment and protein-protein interaction analyses, characterized those as humoral components of the innate immune system and key elements on the response to stimulus.Conclusions Overall, this study represents the first screening of more reliable signatures of physiological adaptation to chronic stress in fish, allowing the future development of novel biomarker models to monitor fish welfare.

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Parental LC-PUFA biosynthesis capacity and nutritional intervention with alpha-linolenic acid affect performance of Sparus aurata progeny

Journal of Experimental Biology ◽

10.1242/jeb.214999 ◽

2020 ◽

Vol 223 (23) ◽

pp. jeb214999

Author(s):

Serhat Turkmen ◽

Maria J. Zamorano ◽

Hanlin Xu ◽

Hipólito Fernández-Palacios ◽

Lidia Robaina ◽

...

Keyword(s):

Developmental Stages ◽

Sparus Aurata ◽

Quality Parameters ◽

Human Consumption ◽

Gilthead Seabream ◽

Alpha Linolenic Acid ◽

Spawning Period ◽

Nutritional Programming ◽

Plant Protein Sources

ABSTRACTEnvironmental factors such as nutritional interventions during early developmental stages affect and establish long-term metabolic changes in all animals. Diet during the spawning period has a nutritional programming effect in offspring of gilthead seabream and affects long-term metabolism. Studies showed modulation of genes such as fads2, which is considered to be a rate-limiting step in the synthesis of n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). However, it is still unknown whether this adaptation is related to the presence of precursors or to limitations in the pre-formed products, n-3 LC-PUFA, contained in the diets used during nutritional programming. This study investigated the combined effects of nutritional programming on Sparusaurata through broodstock diets during the spawning period and in broodfish showing higher or lower fads2 expression levels in the blood after 1 month of feeding with a diet containing high levels of plant protein sources and vegetable oils (VM/VO). Broodfish showing high fads2 expression had a noticeable improvement in spawning quality parameters as well as in the growth of 6 month old offspring when challenged with a high VM/VO diet. Further, nutritional conditioning with 18:3n-3-rich diets had an adverse effect in comparison to progeny obtained from fish fed high fish meal and fish oil (FM/FO) diets, with a reduction in growth of juveniles. Improved growth of progeny from the high fads2 broodstock combined with similar muscle fatty acid profiles is also an excellent option for tailoring and increasing the flesh n-3 LC-PUFA levels to meet the recommended dietary allowances for human consumption.

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