Search Results (2,004)

Selenium (Se) is an essential trace element critical for animal growth and immune function. This study investigated the dietary selenium requirement of juvenile large yellow croaker (Larimichthys crocea) through an 8-week feeding trial. Five experimental diets were formulated by supplementing a basal diet with selenium polysaccharides (Se-PS) at 0, 20, 30, 40, and 50 mg/kg, resulting in analyzed Se concentrations of 0.35, 0.54, 0.71, 0.93, and 1.11 mg/kg, respectively. The results demonstrated that growth performance and feed efficiency improved with increasing dietary selenium, peaking at 0.93 mg/kg before declining at higher levels. Antioxidant enzyme activities—superoxide dismutase (SOD) and catalase (CAT)—in serum and liver tissues exhibited a dose-dependent increase, reaching maximal levels at 1.11 mg/kg. Conversely, malondialdehyde (MDA), a marker of oxidative stress, progressively decreased in both serum and liver, attaining its lowest concentration at 1.11 mg/kg, though this did not differ significantly from the 0.93 mg/kg group (p = 0.056). Tissue selenium accumulation was highest at these optimal dietary levels. Based on the growth performance, oxidative stress response, and tissue selenium retention, the recommended dietary selenium requirement for juvenile large yellow croaker is 0.93 mg/kg. These findings highlight the importance of optimal Se supplementation in aquafeeds to enhance growth and physiological health in farmed fish. Full article

The use of eco-organic ingredients as a source of protein in aquaculture diets needs important attention due to the growing demand for organic seafood products. The present study evaluated the effects of fish meal substitution by different organic ingredients on the growth, body composition, retention efficiency, enzyme activity, and nutrient digestibility of white shrimp Penaeus vannamei. The four dietary formulations tested were formulated with organic ingredients and the fish meal was replaced by the following organic protein meals: Iberian pig viscera meal (PIG), trout by-product meal (TRO), insect meal (FLY), and organic vegetable meal (WHT), in addition to a control diet (CON) that included 15% fish meal. A growth trial was carried out for 83 days, raising 1 g shrimp to commercial size (20 g). Shrimp were stocked at 167 shrimp/m³ (15 individuals per 90 L tank). The results showed that the growth obtained by shrimp fed with TRO (19.27 g) and PIG (19.35 g) were similar in weight gain to the control diet (20.76 g), while FLY (16.04 g) and WHT (16.73 g) meals resulted in a significant lower final weight. The FLY diet showed significantly lower protein digestibility (68.89%) compared to the CON, PIG, TRO, and WHT diets, and significantly higher trypsin activity (0.17 mU/g) compared to shrimp fed with the PIG, TRO, and WHT diets. Shrimp fed with WHT have a significantly lower body weight percentage of protein (19.69%) than shrimp fed with the WHT and TRO diets, and some significant differences in dietary aminoacidic levels affecting amino acid body composition. These results indicate that Iberian pig viscera and trout by-product meal can successfully replace fish meal in Pacific white shrimp aquaculture. Full article

Siniperca chuatsi is an important high-quality freshwater aquaculture species in China. In nature, it feeds exclusively on live food. In this study, domesticated juvenile S. chuatsi were divided into three groups and fed live food (group L), compound feed (group C), or a mixed diet (group M) for three months to investigate the molecular mechanisms underlying adaptation to compound feed. Histopathological examination revealed that compound feed consumption induced looser liver cell arrangement, hepatocyte morphological irregularities, and vacuolization. A total of 1033 and 1428 differentially expressed genes (DEGs), and 187 and 184 differential metabolites (DMs), were identified in the C vs. L and C vs. M groups, respectively. Transcriptomic analysis revealed that the significantly and commonly enriched metabolic pathways shared by both comparison groups were predominantly involved in amino acid, carbohydrate, and lipid metabolisms. Metabolomic analysis demonstrated that the significantly and commonly enriched metabolic pathways shared by both comparison groups were the arachidonic acid metabolism, linoleic acid metabolism, oxidative phosphorylation, and PPAR signalling pathways. Integrated omics analysis showed that the PPAR signalling pathway was the only significantly co-enriched pathway across both omics datasets. This study provides new insights into the molecular mechanisms of compound feed adaptation and provides theoretical support for selecting feed traits in S. chuatsi. Full article

This literature-based review draws on studies of thirty-four fish species; most are from northern temperate regions. Fish have flexible and indeterminate growth, and often they do not reach their growth and size potential. They may become stunted with impaired growth and early maturity, chiefly as a phenotypically plastic reaction. The main causes of stunted growth are negatively density-dependent food availability and keen intraspecific competition leading to environmental stress. Typically, their growth levels off early in life as energy consumptions approach energy costs of maintenance. Females typically attain maturity soon after the energy surplus from feeding starts to decrease. Males are often more variable in size at maturity owing to alternative mating strategies, and their size at maturity depends on both species-specific mating behaviours and environmental opportunities. In polyphenic/polymorphic populations, one phenotype may be stunted and the other phenotype non-stunted; stunted individuals do not perform the required ontogenetic niche shift needed to grow larger. The adult morphology of stunted fish is typically like the morphology of juveniles. Their secondary sexual characters are less pronounced, and they phenotypically retain adaptation to their early feeding niche, which is different from that of large-growing individuals. There are open questions regarding to what extent genetics and epigenetics regulate the life histories of stunted phenotypes. Full article

Animal protein production represents a complex system of lives transformed into nutrition, with profound ethical and environmental implications. This study provides a quantitative analysis of animal lives required to produce human-consumable protein across major food production systems. Categorizing animal lives based on cognitive complexity and accounting for all lives involved in production, including direct harvests, reproductive animals, and feed species, reveals dramatic variations in protein efficiency. The analysis considers two categories of animal life: complex-cognitive lives (e.g., mammals, birds, cephalopods) and pain-capable lives (e.g., fish, crustaceans). Calculating protein yield per life demonstrates efficiency differences spanning more than five orders of magnitude, from 2 g per complex-cognitive life for baby octopus to 390,000 g per life for bovine dairy systems. Key findings expose disparities between terrestrial and marine protein production. Terrestrial systems involving mammals and birds show higher protein yields and exclusively involve complex-cognitive lives, while marine systems rely predominantly on pain-capable lives across complex food chains. Dairy production emerges as the most efficient system. Aquaculture systems reveal complex dynamics, with farmed carnivorous fish requiring hundreds of feed fish lives to produce protein, compared to omnivorous species that demonstrate improved efficiency. Beyond quantitative analysis, this research provides a framework for understanding the ethical and ecological dimensions of protein production, offering insights for potential systemic innovations. Full article

This research examined the impact of dietary supplementation with Phlogacanthus pulcherrimus extract (PPE) on the growth, disease resistance, and expression of immune-, growth-, and antioxidant-related genes in Labeo chrysophekadion. Over 150 days, 90 fish from each group were fed diets with 0 (control), 0.25, 0.50, or 0.75 g/kg of PPE. Phytochemical analysis revealed phenolics (96.00 mg GAE/g), flavonoids (17.55 mg QE/g), anthraquinones, and triterpenoids, along with moderate antioxidant activity (IC₅₀ = 1314.08 μg/mL). One-way ANOVA of growth indices, including weight gain, specific growth rate, feed conversion ratio, and survival rate, revealed no significant differences (p > 0.05); however, PPE supplementation significantly enhanced immune and antioxidant gene expression. IL-1β was significantly (p < 0.05) upregulated at all doses, with the highest expression observed at 0.50 g/kg, showing a fivefold increase compared to the control. In addition, the highest relative expressions of IGF-1 and CAT were found at 0.75 g/kg, with 4.5-fold and 3.5-fold increases compared to the control, respectively. PPE at 0.75 g/kg decreased the cumulative mortality rate (CMR) by 20% compared to the control group, which had a CMR of 50% following exposure to Aeromonas hydrophila. PPE acted as an effective immunostimulant and antioxidant, supporting reduced antibiotic reliance in aquaculture. Full article

In recent years, edible insects have gained significant attention as a sustainable and innovative source of feed for animal nutrition due to their excellent content of protein, fats, vitamins, and chitin. Among these, chitin is the least studied nutritional component, despite its promising properties and potential benefits. Chitin, an important polysaccharide found in the exoskeleton of arthropods, including insects, presents both negative and positive aspects in animal nutrition. As is known, the main drawback is its digestibility, which varies among livestock animal species depending on their ability to produce chitinase. However, chitin also exhibits benefits, including the enhancement of gut microbiota and immune response, together with the reduction in cholesterol and pathogen levels in animals. This review aims to summarise the current knowledge on the effects of chitin derived from edible insects on animal nutrition by analysing both the negative aspects and benefits for the different farmed animals for which insect feeding is legally permitted (fish, poultry, and pigs), while proposing future research directions. Full article

Restaurants and open markets generate considerable quantities of organic waste. Converting these residues into poultry feed ingredients offers a sustainable disposal route. This study aimed to evaluate the nutritional and sensory viability of a novel feed complement formulated from Bonito fish meal (Sarda chiliensis chiliensis) and Única potato peel flour (Solanum tuberosum L. cv. Única). This study was conducted in three phases: (i) production and nutritional characterization of the two by-product flours; (ii) formulation of a 48:52 (w/w) blend, incorporated into broiler diets at 15%, 30%, and 45% replacement levels over a 7-week trial divided into starter (3 weeks), grower (3 weeks), and finisher (1 week) phases; and (iii) assessment of growth performance (weight gain, final weight, and feed conversion ratio), followed by a sensory evaluation of the resulting meat using a Check-All-That-Apply (CATA) analysis. The Bonito fish meal exhibited 50.78% protein, while the Única potato peel flour was rich in carbohydrates (74.08%). The final body weights of broiler chickens ranged from 1872.1 to 1886.4 g across treatments, and the average feed conversion ratio across all groups was 0.65. Replacing up to 45% of commercial feed with the formulated complement did not significantly affect growth performance (p > 0.05). Sensory analysis revealed that meat from chickens receiving 15% and 45% substitution levels was preferred in terms of aroma and taste, whereas the control group was rated higher in appearance. These findings suggest that the formulated feed complement may represent a viable poultry-feed alternative with potential sensory and economic benefits, supporting future circular-economy strategies. Full article

The uMlazi River receives effluents from wastewater work before feeding the Shongweni Dam. However, local communities are consuming fish from this dam for protein supplements. This study was undertaken to investigate the metal concentrations in the water and sediment, the general health of Coptodon rendalli and Oreochromis mossambicus, and metal bioaccumulation. Sampling was conducted during the dry (July–August) and wet seasons (November and December) in 2021. Water was sampled using acid-pre-treated sampling bottles, whereas sediment was collected using the Van Veen grab at the inflow, middle, and dam wall. Fish were collected, and their tissues were digested using aqua regia. Metal concentrations were measured using inductively coupled plasma optical emission spectroscopy (ICP-OES). This data manuscript reports the physical parameters of the water and concentrations of antimony, arsenic, cadmium, copper, iron, manganese, lead, selenium, and strontium in the water and sediment from the Shongweni Dam. Moreover, the fish morphometric data and metal concentrations observed in the muscle are also presented. This data could be used as baseline information on metal concentrations in the Shongweni Dam. Moreover, it provides insight into the potential impact of wastewater effluents on metal increases in freshwater bodies. Full article

Accurate evaluation of fish feeding intensity is crucial for optimizing aquaculture efficiency and the healthy growth of fish. Previous methods mainly rely on single-modal approaches (e.g., audio or visual). However, the complex underwater environment makes single-modal monitoring methods face significant challenges: visual systems are severely affected by water turbidity, lighting conditions, and fish occlusion, while acoustic systems suffer from background noise. Although existing studies have attempted to combine acoustic and visual information, most adopt simple feature-level fusion strategies, which fail to fully explore the complementary advantages of the two modalities under different environmental conditions and lack dynamic evaluation mechanisms for modal reliability. To address these problems, we propose the Adaptive Cross-modal Attention Fusion Network (ACAF-Net), a cross-modal complementarity learning framework with a two-stage attention fusion mechanism: (1) a cross-modal enhancement stage that enriches individual representations through Low-rank Bilinear Pooling and learnable fusion weights; (2) an adaptive attention fusion stage that dynamically weights acoustic and visual features based on complementarity and environmental reliability. Our framework incorporates dimension alignment strategies and attention mechanisms to capture temporal–spatial complementarity between acoustic feeding signals and visual behavioral patterns. Extensive experiments demonstrate superior performance compared to single-modal and conventional fusion approaches, with 6.4% accuracy improvement. The results validate the effectiveness of exploiting cross-modal complementarity for underwater behavioral analysis and establish a foundation for intelligent aquaculture monitoring systems. Full article

Bycatch is the most common cause of death of small delphinids worldwide, including the Mediterranean Sea. The diagnosis of bycatch as cause of death in stranded cetaceans depends on the cumulative presence of multiple findings, termed bycatch criteria. In this study, we retrospectively evaluated the presence of bycatch criteria in 138 necropsied cetaceans, 136 stranded and 2 confirmed bycaught, in the Catalan Mediterranean Sea across a 13-year period. With the aim of identifying the most specific and reliable bycatch criteria, the animals’ cause of death was classified as either bycaught or other causes. Animals were necropsied according to standard procedures with complete histopathological examination and ancillary diagnostic techniques. We reviewed the necropsy reports and photographs of 138 cetaceans of seven species. Bycatch had been determined as the cause of death/stranding in 40 (29%) necropsied cetaceans. Both sexes were equally represented in the bycatch group. Bycatch was diagnosed in the Mediterranean common bottlenose dolphin (10/14; 71.4%), striped dolphin (29/108; 26.9%), and Risso’s dolphin (1/11; 9.1%). Sixty-seven out of 98 (68.3%) cetaceans that had been classified as non-bycatch had one or two bycatch criteria. Cetaceans with two and three major criteria had an overlap of causes of death, as some animals were diagnosed with bycatch and others with other causes of mortality. Animals with four criteria were invariably diagnosed as being bycaught. Recent feeding, absence of disease, good nutritional status, marks of fishing gear, multiorgan intravascular gas bubbles, hyphema and amputations or sharp incisions presumably inflicted by humans were significantly more likely to result in a diagnosis of bycatch, while loss of teeth and cranial fractures were not. None of the dolphins diagnosed as bycatch had ingested fishing gear. Our results highlight the relevance of bycatch as the cause of death of dolphins in the Mediterranean and suggest that some criteria traditionally linked to bycatch are not specific for bycatch in our region. Full article

The aquaculture industry has experienced considerable growth in recent decades, stimulating research into sustainable and functional feed formulations, mainly related to using high-quality, safe, and environmentally friendly feed ingredients. The employment of immunomodulatory additives is a promising strategy to enhance fish health and performance. In this study, the effects of the ghrelin analog GHRP-6 peptide included in the diet (500 µg/kg of feed) on the endocrine and immune responses of Sparus aurata following Incomplete Freund’s adjuvant (IFA) treatment were assessed. After 97 days, fish were intraperitoneally injected with 100 µL of saline solution or IFA/100 g fish and sampled 72 h post-injection. Our results indicated that fish fed GHRP-6 maintained stable plasma levels of lactate, triglycerides, and cortisol after IFA treatment, in contrast to control-fed fish, which showed significant metabolic stress. Circulating immunoglobulin levels enhanced significantly in the GHRP-6/IFA group, suggesting a stimulated humoral immune response. Transcriptomics analysis revealed that the anterior intestine was the most responsive tissue, with upregulation of il10, il15, il34, and mx1, indicating mucosal immune activation. In the spleen, GHRP-6-fed fish increased il8, il10, and ighm expression, highlighting a balanced pro- and anti-inflammatory response and support for adaptive immunity. Multivariate analysis confirmed that dietary GHRP-6 modulates immune gene expression in a tissue- and stimulus-specific manner, without inducing histological alterations in the intestine or spleen. Taken together, these preliminary results indicate that this peptide is a viable and safe dietary supplement to improve immune resilience and increase the production efficiency of S. aurata and suggest a protective effect on the fish’s immune system in this species. Full article

Aquaculture is vital for global food security but faces challenges like disease, water quality control, and resource optimization. Digital twin technology, a real-time virtual replica of physical aquaculture systems, emerges as a transformative solution. By integrating sensors and data analytics, it enables monitoring and optimization of water quality, feed efficiency, fish health, and operations. This review explores the current adoption status of digital twins in aquaculture, highlighting applications in real-time monitoring and system optimization. It addresses key implementation challenges, including data integration and scalability, and identifies emerging opportunities for advancing sustainable, intelligent aquaculture practices. Full article

Aquaculture is a key food production sector responsible for meeting the nutritional needs of a rapidly growing global population. However, the emergence of disease outbreaks has become a major challenge for the aquaculture industry, resulting in significant economic losses. The use of costly and toxic antibiotics for treatment has a negative impact on the aquatic environment. Consequently, there has been a growing interest in probiotics as a non-antibiotic approach to manage disease outbreaks and improve fish performance. The use of the yeast Saccharomyces cerevisiae (SC) has shown remarkable benefits in aquaculture. In February 2025, a systematic search was conducted based on the Web of Science (WoS) database for the period 2015–2025 to identify relevant studies investigating the beneficial effects of SC in aquaculture. After searching on WoS, 466 documents were found and analyzed using R-bibliometric package for comprehensive analysis to identify research gap, trends, and distribution of global literature that focuses on SC in aquaculture. The most relevant and recent articles were reviewed, summarized and discussed. The yeast SC have shown a wide range of benefits, including improved growth performance, feed efficiency, enhanced diversity of the gut microbiome and immune response. The implementation of SC is becoming a recent trend and its efficacy in aquatic environments has been thoroughly investigated. This review aims to provide a valuable insight into SC as one of the most important aquaculture probiotics. It also emphasizes the need for further research to fully understand its benefits and the way it works. Full article

Selenium nanoparticles (SeNPs), with their high absorption and antioxidant properties, hold promise as feed additives in aquaculture, enhancing growth and reproductive health in fish. This review evaluates how selenium nanoparticles influence growth and reproductive traits in Asian seabass (L. calcarifer). Using the PRISMA approach, we examined the impacts of selenium nanoparticles (SeNPs) on the growth performance and gonadal development of Asian seabass (L. calcarifer) by synthesizing findings from the existing literature. Meta-analysis explored that selenium nanoparticles (SeNPs) supplementation significantly improved specific growth rate (SGR) (pooled effect size = 3.97; 95% CI: 3.68–4.26) and feed conversion ratio (FCR) (pooled effect size = 0.81; 95% CI: 0.75–0.86), with low heterogeneity. Regarding reproductive outcomes, SeNPs enhanced gonadal development, sperm quality, and steroidogenesis. Significant improvements were observed in gonadosomatic index (effect size = 0.5), fertilization rate (0.6), and testosterone levels (0.5), along with a reduction in abnormal embryogenesis (−0.3) (p < 0.05). While an optimal level of SeNPs is effective for enhancing aquaculture performance, excessive use may lead to toxicity; therefore, their economic viability, environmental impact, and sustainability in large-scale aquaculture warrant further investigation. This review provides insights for researchers, policymakers, and industry stakeholders on the potential of SeNPs in advancing sustainable aquaculture through fish productivity and reproductive performance. Full article