Protein Retention Research Articles

Effect of Distiller's Dried Grain with Soluble (DDGS) in Artificial Feed on the Growth, Protein Retention, and Survival Rate of the Pacific White Shrimp (Litopenaeus vannamei)

Effect of Distiller's Dried Grain with Soluble (DDGS) in Artificial Feed on the Growth, Protein Retention, and Survival Rate of the Pacific White Shrimp (Litopenaeus vannamei)

Quality evaluation of Idli prepared from betel leaves essential oil nanoemulsion treated stored batter

The demand for clean-label, natural preservation in fermented foods requires innovative methods to extend shelf-life while maintaining quality. This study evaluates Idli quality from batter stored with and without 5% betel leaf essential oil-based nanoemulsion (BLEONE) at 30 °C and 4 °C. Color, texture, microbial growth, proximate composition and sensory attributes were assessed using standard methods, with statistical analysis via ANOVA and Tukey's post-hoc test (p < 0.05). BLEONE-treated Idli showed 30.2% reduced hardness, 17.1% better color retention, and 0.61 log CFU/g less microbial growth after 5 days, inhibiting harmful microbes and supporting beneficial lactic acid bacteria. At 30 °C, BLEONE-treated Idli maintained quality for 7 days versus 2 days for controls. Moisture, protein, and fat retention improved by 3.4%, 7.3%, and 6.2%. Sensory scores for taste, mouthfeel, and acceptability increased by 3.5%, 4.1%, and 3.8% after 10 days at 4 °C. BLEONE-treated batter produced acceptable Idli for up to 25 days at 4 °C, compared to 10 days for controls, extending shelf-life by 150%. This study shows BLEONE is an effective natural preservative for Idli, extending shelf-life and maintaining quality at ambient and refrigerated temperatures. These findings suggest potential for clean-label preservation methods for fermented foods, potentially revolutionizing the food preservation industry.

RNA nanotherapeutics with fibrosis overexpression and retention for MASH treatment

Metabolic dysfunction-associated steatohepatitis (MASH) poses challenges for targeted delivery and retention of therapeutic proteins due to excess extracellular matrix (ECM). Here we present a new approach to treat MASH, termed “Fibrosis overexpression and retention (FORT)”. In this strategy, we design (1) retinoid-derivative lipid nanoparticle (LNP) to enable enhanced mRNA overexpression in fibrotic regions, and (2) mRNA modifications which facilitate anchoring of therapeutic proteins in ECM. LNPs containing carboxyl-retinoids, rather than alcohol- or ester-retinoids, effectively deliver mRNA with over 10-fold enhancement of protein expression in fibrotic livers. The carboxyl-retinoid rearrangement on the LNP surface improves protein binding and membrane fusion. Therapeutic proteins are then engineered with an endogenous collagen-binding domain. These fusion proteins exhibit increased retention in fibrotic lesions and reduced systemic toxicity. In vivo, fibrosis-targeting LNPs encoding fusion proteins demonstrate superior therapeutic efficacy in three clinically relevant male-animal MASH models. This approach holds promise in fibrotic diseases unsuited for protein injection.

Modification of pea protein isolates by high-intensity ultrasonication: Functional, structural and nutritional properties

The current study aims to modify the functional, physical, structural and nutritional characteristics of pea protein isolate. High-intensity ultrasound treatment was used at 20 kHz frequency and 25 % amplitude for 10 (US10), 20 (US20), or 30 (US30) min. Results indicated that ultrasound application enhanced the protein solubility and zeta potential. When compared to control samples, the foaming capacity (FC) and stability (FS) as well as emulsion activity (EA) and stability (ES) were also increased from 157.5, 42.03, 46.25 and 53.75 % up to 182.5, 81.57, 72.50 and 67.50 %, respectively. Besides, particle size was found to be lower for ultrasound treated samples (92.9–131.1 nm) in comparison to that of untreated commercial pea protein isolate (161.9 nm). Moreover, while the bioaccessibility of pea protein in untreated sample was calculated as 28.90 %, ultrasonication increased the retention of pea protein up to 49.36 %. It can be concluded from the results that the ultrasonication process can be used as an advantageous, green and non-thermal tool for obtaining protein isolates with improved techno-functional properties and nutritional quality. Therefore, this treatment might improve the characteristics, and thus increase the utilization of plant-based proteins, especially pea protein, in various food systems.

Techno-functional properties and structural characteristics of cricket protein concentrates affected by pre-treatments and ultrafiltration/diafiltration processes

This study aimed to evaluate different pre-treatments on cricket flour (CF), solvent-defatting (CFH), and supercritical-defatting (CFS) to obtain cricket protein concentrate (CPC) by ultrafiltration (UF)-diafiltration (DF) and evaluate the UF-DF performance, techno-functional properties, and digestibility. Results showed that defatting efficiency was 63 % and 85 % for solvent-defatting and supercritical fluid defatting, respectively. The supercritical fluid extraction process decreased the protein solubility and affected the UF performance, decreasing protein retention by 33 %. However, the soluble protein of the generated concentrates was higher than 90 %. Protein concentrates showed a better foaming capacity at pH 5.0 and 7.0, while the oil-holding capacity (1.95–2.20 g/g) decreased in defatted concentrates but was higher than water-holding (0.30–0.60 g/g). Emulsion activity (45–50 %) was not affected by pre-treatments (p > 0.05). Protein digestibility ranged from 71 to 75 % (p < 0.05). Supercritical fluid defatting and ultrafiltration-diafiltration processes were suitable for obtaining cricket protein concentrates.

Local delivery of cell surface-targeted immunocytokines programs systemic antitumor immunity

Systemically administered cytokines are potent immunotherapeutics but can cause severe dose-limiting toxicities. To overcome this challenge, cytokines have been engineered for intratumoral retention after local delivery. However, despite inducing regression of treated lesions, tumor-localized cytokines often elicit only modest responses at distal untreated tumors. In the present study, we report a localized cytokine therapy that safely elicits systemic antitumor immunity by targeting the ubiquitous leukocyte receptor CD45. CD45-targeted immunocytokines have lower internalization rates relative to wild-type counterparts, leading to sustained downstream cis and trans signaling between lymphocytes. A single intratumoral dose of αCD45-interleukin (IL)-12 followed by a single dose of αCD45-IL-15 eradicated treated tumors and untreated distal lesions in multiple syngeneic mouse tumor models without toxicity. Mechanistically, CD45-targeted cytokines reprogrammed tumor-specific CD8+ T cells in the tumor-draining lymph nodes to have an antiviral transcriptional signature. CD45 anchoring represents a broad platform for protein retention by host immune cells for use in immunotherapy.

Ubiquitin-Specific Protease 22 Plays a Key Role in Increasing Extracellular Vesicle Secretion and Regulating Cell Motility of Lung Adenocarcinoma.

Tumor-derived extracellular vesicles (EVs) are potential biomarkers for tumors, but their reliable molecular targets have not been identified. The previous study confirms that ubiquitin-specific protease 22 (USP22) promotes lung adenocarcinoma (LUAD) metastasis in vivo and in vitro. Moreover, USP22 regulates endocytosis of tumor cells and localizes to late endosomes. However, the role of USP22 in the secretion of tumor cell-derived EVs remains unknown. In this study, it demonstrates that USP22 increases the secretion of tumor cell-derived EVs and accelerates their migration and invasion, invadopodia formation, and angiogenesis via EV transfer. USP22 enhances EV secretion by upregulating myosin IB (MYO1B). This study further discovers that USP22 activated the SRC signaling pathway by upregulating the molecule KDEL endoplasmic reticulum protein retention receptor 1 (KDELR1), thereby contributing to LUAD cell progression. The study provides novel insights into the role of USP22 in EV secretion and cell motility regulation in LUAD.

Effect of taurine on growth and immune response of Pacific white shrimp (Litopenaeus vannamei) cultured at different temperatures

Low temperature is a common challenge in the culture of Pacific white shrimp (Litopenaeus vannamei), and taurine is a potential nutrient that may improve its cold-resistance. This experiment aimed to investigate effects of dietary taurine on growth and immune response of Pacific white shrimp cultured at normal and cold temperatures. Six diets were supplemented with increasing levels of taurine (0, 0.2, 0.4, 0.6, 0.8 and 1.0%) and fed to shrimp (1.59 ± 0.03 g) reared at two water temperatures (28 °C and 20 °C) for 8 weeks. The results showed that compared with 28 °C, shrimp reared at 20 °C showed lower growth performance, feed utilization, apparent digestibility and total hemocyte count (THC) (P < 0.05), but higher content of serum glucose, intracellular reactive oxygen species (ROS) and Ca2+, malonaldehyde (MDA) and apoptosis rate (P < 0.05), indicating a higher risk of oxidative damage during low temperature stress. Interestingly, shrimp could cope with cold stress by changing hemocyte composition, increasing antioxidant enzyme activity and genes expression of apoptosis and autophagy. The effect of taurine was different at different temperatures. At 28 °C, taurine supplementation improved growth rate of shrimp by increasing digestive enzyme activities, digestion absorption rate and nutrient utilization. Based on the quadratic model of weight gain rate, feed efficiency, protein retention efficiency and the broken line model of apparent digestibility coefficients of protein, the amount of taurine required for shrimp reared at 28 °C was 0.57–0.60% of dry diet. At 20 °C, taurine increased the number of THC, granulocytes, semi-granulocytes, the activities of antioxidant enzymes such as superoxide dismutase and catalase, and decreased the content of ROS in the cells, which may enhance cold resistance of shrimp. Moreover, taurine supplementation down-regulated mRNA expression of cell apoptosis genes (cyt-c, caspase-9 and caspase-3) and up-regulated mRNA expression of cell autophagy genes (atg1, atg13, atg7 and lc3) (P < 0.05), which may help to maintain cell stability at 20 °C. The optimal requirement of taurine in shrimp reared at 20 °C was 0.56–0.66% of dry diet in this experiment based on THC and MDA content. In conclusion, our study suggests that appropriate taurine promotes growth and feed utilization at optimal temperature and enhances the stability of hemocyte at low temperature in white shrimp.

Consolidation and cytotoxicity analysis of a purification strategy for biotechnological xylitol production using fixed bed column adsorption and nanofiltration membranes

Agro-industrial waste is increasingly utilized in biotechnological processes to convert lignocellulosic materials into high-value products, such as xylitol. This polyol can be produced using biotechnological methods that mitigate environmental impacts, but it entails high purification costs. The article proposes a comparative study between two sequential strategies for purifying biotechnological xylitol. The first strategy involves membrane filtration followed by column adsorption. While the second strategy only covers column adsorption with twice the adsorbent bed. Additionally, the study includes a cytotoxicity evaluation of various purified xylitol fractions. Column adsorption was conducted at 70 °C with a flow rate of 1.2 mL min−1 using activated carbon as the adsorbent. It proved to be efficient in separating colored compounds, proteins, and ethanol, with retention coefficients of 99.23 %, 84.0 %, and 96.71 %, respectively. The purification factor of xylitol/ethanol was 14.84. Nanofiltration was performed using a poly (piperazine amide) membrane at 40 °C and 30 bar, resulting in a protein retention of 43.55 % and a xylitol purity of 27.73 %. Finally, purified xylitol fractions underwent cytotoxicity analysis using the MTT assay, conducted in intestinal epithelial cells (Caco-2). One of the analyzed fractions did not induce toxicity, demonstrating that activated carbon column adsorption was the most effective strategy for purifying biotechnologically produced xylitol. These findings contribute to enhancing the viability of biotechnological xylitol production from sugarcane bagasse hemicellulosic hydrolysate.

Coated Crystalline Amino Acid Supplementation May Assist Higher Soybean Meal Inclusion in Diets for Nile Tilapia (Oreochromis Niloticus) With Improved Protein Assimilation and Retention

The aquaculture industry has previously relied on high-quality fishmeal (FM) to fabricate diets of excellent standards. However, plant-based proteins such as soybean are more economic for low-value fish species, for example, tilapia and carp, and fishmeal use has been significantly lessened. Previous studies have addressed standard soybean meal (SBM) sources in aquafeeds seldom addressing essential amino acid correction. An eight-week feeding trial was conducted to evaluate the replacement of fish meal with soybean meal concentrate in Nile tilapia (Oreochromis niloticus) using a semi-purified diet against a Low Temperature (LT) fishmeal as a primary reference protein. Four diets with varying levels of soybean meal were evaluated and compared to a control diet of 100 % fish meal. Three diets containing 20, 40, and 80 % soybean protein concentrate (SBPC) were examined. The fourth diet consisted of 80 % SBPC and supplementation with two essential amino acids: lysine and methionine (80SBPCAA) in a coated form. Daily growth values highlight similar rates when tilapia was fed 100FM and 40SBPC diets. No differences were observed in the final mean weights for all soybean-fed tilapia, but they were marginally lower than the 100FM control diet group. The 80SBPC diet showed the poorest feed conversion ratio (FCR) at 1.31 and protein efficiency ratio (PER) at 2.19. However, the 80SBPCAA diet showed a significantly improved percent weight gain for tilapia compared to the 80SBPC-fed tilapia. PER was significantly higher at 2.47 and had a better Apparent Net Protein Utilization (ANPU) value of 28.51 % compared to un-supplemented 80SBPC-fed tilapia (25.48 %). These results confirmed that high-quality fishmeal can be substituted by up to 40 % SBPC alone and without any detrimental effects on growth or carcass composition in juvenile tilapia. Crystalline coated essential amino acid supplementation showed marginal improvement of performance for tilapia at high SBPC inclusion level.

Digestive Profiles of Human Milk, Recombinant Human and Bovine Lactoferrin: Comparing the Retained Intact Protein and Peptide Release.

Lactoferrin (LF) is a major component of human milk. LF supplementation (currently bovine) supports the immune system and helps maintain iron homeostasis in adults. No recombinant human lactoferrin (rhLF) is available for commercial food use. To determine the extent to which rhLF (Effera™) produced by Komagataella phaffii digests similarly to hmLF, a validated in vitro digestion protocol was carried out. Bovine LF (bLF) was used as an additional control, as it is approved for use in various food categories. This study compared the extent of intact protein retention and the profile of peptides released in hmLF, bLF and rhLF (each with low and high iron saturation) across simulated adult gastric and intestinal digestion using gel electrophoresis, ELISA and LC-MS. Intact LF retention across digestion was similar across LF types, but the highest iron-saturated hmLF had greater retention in the simulated gastric fluid than all other sample types. Peptides identified in digested hmLF samples strongly correlated with digested rhLF samples (0.86 < r < 0.92 in the gastric phase and 0.63 < r < 0.70 in the intestinal phase), whereas digested bLF samples were significantly different. These findings support the potential for rhLF as a food ingredient for human consumption.

Justification of membrane filtration parameters in the production of whey protein isolate

The research was aimed at studying the combined effect of micro- and ultrafiltration technological parameters for justification of rational modes in the production of whey protein isolate. The process flow of whey protein isolate production was determined. It includes whey purification from casein dust and fat, pasteurization, ultrafiltration, microfiltration, ultrafiltration (combined with diafiltration), spray drying. Concentration was carried out from a dry matter mass fraction of 5.4-5.6% to 11.3-12.6% (protein concentration factor is 6.5-13). Microfiltration of the resulting retentate was used to maximize disposal of milk fat. The process was carried out using ceramic membranes (pore size from 0.14 pm to 1.4 pm). Their protein retention capacity was 0.2-0.4%, fat retention capacity was 64.6-76.2%. Rational microfiltration modes were selected. They are inlet pressure 0.15-0.2 MPa and temperature 10-15 °C. The microfiltration permeate was treated via repeated ultrafiltration combining it with diafiltration. It was possible to achieve the protein content in dry matter of the product not more than 87% using diafiltration with half the volume of water. However, it does not meet the requirements for the isolate. Increasing the amount of water for diafiltration caused a rise in the protein content in dry matter of the concentrate. The protein mass fraction in the whey protein isolate before drying was at least 17%. The whey protein isolate powder was characterized by the high protein content (93% in terms of SNF), quality and safety indicators met the requirements of regulatory documentation.

The effect of feeding level on protein and energy utilization in young and mature Kacang goats

Abstract A study was conducted to evaluate the amount of feeding on nutrient utilization of Kacang goats. This study used 16 heads, consisting of 8 young Kacang goats (5-6 months old), weighing 12.75 kg (CV = 2.4%), and 8 mature Kacang goats (12-15 months old), weighing 17.34 kg (CV = 2.7%). The diet was in the form of pellets, consisting of 25% wheat straw, 32% soybean meal, 39% rice bran, 3% sugarcane molasses, and 1% minerals. This study used a completely randomized design (CRD) in a nested structure. The main factor (the nest) was the age of the goat, i.e. young and mature, while the second factor (the nested factor) was feeding level, i.e. low (maintenance level) and high (twice maintenance level). The parameters were dry matter intake (DMI), dry matter digestibility (DMD), protein and energy intake, protein and energy digestibility, protein and energy retention, body weight gain (BWG), and feed conversion. The results showed the goat of high feeding level had higher DMI (P&lt;0.05) than that of low feeding level, both in the young goat (243 g/d vs 466 g/d) and the mature goat (303g/d vs 657). There was no significant difference (P&gt;0.05) in DMD between feeding levels and between age of goats (averaged 73.67%). The goats of high level had higher (P&lt;0.01) nutrients retention in goats and the mature goats. The goats of high feeding level had significantly higher (P&lt;0.05) BWG than that of low feeding level (14.64 g/d vs 41.95 g/d in the young goat and 18.35 g/d vs 58.77 g/d in the mature goat). The high feeding level resulted in lower FCR (P&lt;0.01) than the lower feeding level, both in the young goats (16.40 vs 11.44) and in the mature goats (16.47 vs 11.47). It can be concluded that young and mature Kacang goats had similar abilities in feed digestion. The higher feeding level resulted in the better utilization of dietary protein and energy, and productivity of the goat.

Comparison of Different Extraction and Purification Methods of Lime Peel Pectin and Evaluation of Physiochemical, Rheological, and Textural Properties

Background:: Pectin production has recently attracted considerable research interest due to its various applications arising from its unique characteristics. Lime peel, as a by-product of juice factories, has a promising potential for pectin extraction. Methods:: Lime peel pectin samples were extracted by three extraction processes: a) 90°C of heating for 120 min, b) 90°C of heating for 90 min and then 32 min of sonication, and c) 80°C of heating for 60 min and then 22 min of sonication. Then, they were purified either by ethanol or sodium caseinate (SC) and characterized. Results:: SC purification did not enhance the pectin yield; rather, it diminished the level of nonpectin components and resulted in purer pectin (i.e., lower sugar content). The samples purified with SC showed much lower viscosity in solution and storage modulus than the samples purified with ethanol, which could be attributed to their lower sugar content and higher pH (~ 4.6 vs. 2). However, pectin samples purified with SC had a relatively high sugar gel consistency, maybe due to protein retention in their structure as well as the preferential hydration effect of added sucrose. Conclusion:: The compact and extended conformations of the pectin sample, which was extracted by “(c) extraction method” and purified with ethanol, resulted in its high viscosity and storage modulus in solution and the highest gel consistency (16.91 Kg.s) compared to the other samples. Regardless of the conditions of extraction procedures, the purification method had a considerable impact on the pectin samples’ characteristics and potential applications.

Advancing HIC method development: Retention-time modeling and tuning selectivity with ternary mobile-phase systems

The use of a ternary mobile-phase system comprising ammonium sulphate, sodium chloride, and phosphate buffer was explored to tune retention and enhance selectivity in hydrophobic interaction chromatography. The accuracy of the linear solvent-strength model to predict protein retention with the ternary mobile-phase system based on isocratic scouting runs is limited, as the extrapolated retention factor at aqueous buffer conditions (k0) cannot be reliably established. The Jandera retention model utilizing a salt concentration averaged retention factor (k¯0) in aqueous buffer for ternary systems overcomes this bottleneck. Gradient retention factors were derived based on isocratic scouting runs after numerical integration of the isocratic Jandera model, leading to retention-time prediction errors below 11 % for linear gradients. Furthermore, an analytical expression was formulated to predict HIC retention for both linear and segmented linear gradients, considering the linear solvent-strength (LSS) model within ternary salt systems, relying on a fixed k0. The approach involved conducting two gradient scouting runs for each of the two binary salt systems to determine model parameters. Retention-time prediction errors for linear gradients were below 12 % for lysozyme and 3 % for trypsinogen and α-chymotrypsinogen A. Finally, the analytical expression for a ternary mobile-phase system was used in combination with a genetic algorithm to tune the HIC selectivity. With an optimized segmented ternary gradient, a critical-pair separation for a mixture of 7 proteins was achieved within 15 min with retention-time prediction errors ranging between 0.7 and 15.7 %.

Relationship between stocking rate and production of stocker hybrid tilapia and water quality in a mixtotrophic biofloc system

AbstractIntensified production of stocker‐size tilapia can be accomplished using the biofloc technology production system. Stocker‐size tilapia (ca. 10–200 g/fish) are raised for subsequent stocking for grow‐out to market size. The relationship between stocking rate and the production of stocker‐size hybrid tilapia (Oreochromis aureus × O. niloticus) was evaluated in two studies in outdoor mixotrophic biofloc tanks. Hybrid tilapia were stocked in 18.6‐m2 (15.7‐m3) tanks at 50–150 fish/m2 (59–178 fish/m3) in 25 fish/m2 (30 fish/m3) increments in Study 1 and grown for 141–143 days. Stocking rates evaluated in 4.7‐m2 (3.6‐m3) tanks during Study 2 over 78–79 days ranged from 100 to 300 fish/m2 (132–396 fish/m3) in 25 fish/m2 (33 fish/m3) increments. Linear regression models best described growth to stocker size in both studies. Fish yield increased linearly with stocking rate and ranged from 20.1 to 38.3 kg/m3. Individual weight at harvest was inversely related to stocking rate and ranged from 389.8 to 163.4 g/fish and 155.2 to 81.4 g/fish in Studies 1 and 2, respectively. Partial budget analyses suggested positive net changes in profit with incremental increases in stocking rate for producing a 75‐g stocker. Water quality concentrations were impacted directly by daily feed ration and total feed fed, which increased linearly with stocking rate. In Study 2, whole‐body dry matter, protein, protein retention, and lipid were unaffected by stocking rate, whereas whole‐body ash increased with stocking rate. Whole‐body energy retention significantly decreased with stocking rate. The outdoor mixotrophic biofloc production system is well suited for intensive production of hybrid tilapia stockers. However, additional replicated research and economic analysis are needed to evaluate stocking rate and culture duration to produce specific‐sized stocker hybrid tilapia.

Online Mixed-Bed Ion Exchange Chromatography for Native Top-Down Proteomics of Complex Mixtures.

Native top-down mass spectrometry (nTDMS) allows characterization of protein structure and noncovalent interactions with simultaneous sequence mapping and proteoform characterization. The majority of nTDMS studies utilize purified recombinant proteins, with significant challenges hindering application to endogenous systems. To perform native top-down proteomics (nTDP), where endogenous proteins from complex biological systems are analyzed by nTDMS, it is essential to separate proteins under nondenaturing conditions. However, it remains difficult to achieve high resolution with MS-compatible online chromatography while preserving protein tertiary structure and noncovalent interactions. Herein, we report the use of online mixed-bed ion exchange chromatography (IEC) to enable separation of endogenous proteins from complex mixtures under nondenaturing conditions, preserving noncovalent interactions for nTDP analysis. We have successfully detected large proteins (>146 kDa) and identified endogenous metal-binding and oligomeric protein complexes in human heart tissue lysate. The use of a mixed-bed stationary phase allowed retention and elution of proteins over a wide range of isoelectric points without altering the sample or mobile phase pH. Overall, our method provides a simple online IEC-MS platform that can effectively separate proteins from complex mixtures under nondenaturing conditions and preserve higher-order structure for nTDP applications.

Glycerol supplementation in farmed fish species: A review from zootechnical performance to metabolic utilisation

AbstractGlycerol, an abundant by‐product of biodiesel production, has gained attention due to its price and availability for potential commercial applications, and thus utilisation as an animal feed ingredient. This article comprehensively reviews glycerol utilisation in fish and its potential as a dietary ingredient for aquaculture. While dietary inclusion of glycerol may offer cost‐effective energy and metabolic intermediates, studies report inconsistent results regarding its effects on nutrient digestibility, zootechnical performance, and product quality. Recent studies however have demonstrated that dietary glycerol supplementation in fish induces metabolic shifts, such as alterations to gluconeogenesis and/or lipogenesis, modifying energy utilisation. Additionally, glycerol has been proposed to reduce protein catabolism, minimising nitrogen excretion and its environmental impact, but its influence on protein retention remains uncertain. Nevertheless, it is important to carefully consider the balance between feed palatability and these potential metabolic alterations when incorporating glycerol in aquafeeds. This review highlights the need for more studies to expand our understanding of glycerol metabolism in fish, since it does not seem to be metabolised by carnivorous species as much as omnivorous. Future research should explore the effects of glycerol supplementation on fish with different feeding habits and in developmental stages, as well as diverse environmental salinities and temperatures. Insight into the impact of impurities and the optimisation of glycerol inclusion in aquafeeds are recommended to support sustainable aquaculture practices and the utilisation of glycerol as a valuable resource.

Effects of Defatted and Hydrolyzed Black Soldier Fly Larvae Meal as an Alternative Fish Meal in Weaning Pigs.

In Experiment 1, a total of eighteen crossbred ([Landrace × Yorkshire] × Duroc) barrows with an initial body weight of 6.74 ± 0.68 kg were randomly divided into three dietary treatments (one pig per cage and six replicates per treatment) and housed in metabolic cages that were equipped with a feeder and slatted floor to collect urine and feces. In Experiment 2, a total of 96 crossbred ([Landrace × Yorkshire] × Duroc) barrows with an initial body weight of 8.25 ± 0.42 kg were used in the 6-week trial. The pigs were randomly divided into three dietary treatments (three pigs per pen and eight replicates per treatment). In Experiment 1, nutrient composition of defatted black soldier fly larvae meal (BLM) was superior to that of hydrolyzed BLM but lower than that of fish meal (FM). Also, defatted BLM and FM had better apparent total track digestibility (ATTD) of crude protein (CP) and better nitrogen retention (p < 0.05) than hydrolyzed BLM, but there was no significant difference (p > 0.05) between defatted BLM and FM. In Experiment 2, defatted BLM improved (p < 0.05) average daily gain (ADG), feed conversion ratio (FCR), and feed cost per kg gain (FCG) compared with FM. Defatted BLM could replace soybean meal and fish meal as an alternative protein source for weaning pigs.

The Zootechnical Performance, Health State Modulation, Morphology, and Intestinal Microbiome of Nile Tilapia Juveniles Fed with a Functional Blend of Immunostimulants Associated with a Diet High in Soybean Meal

The aim of this study was to evaluate the effect of supplementing feed with a functional mixture of immunomodulators, including β-glucans, nucleotides, ascorbic acid, and alpha-tocopherol, associated with a diet with lower levels of animal protein (11.5%) and higher levels of soybean meal (43.5%), on the zootechnical performance, health, hematological and immunological parameters, intestinal morphology, centesimal composition, and intestinal microbiome of juvenile Nile tilapia (initial weight 1.88 g ± 0.25 g, mean ± standard deviation). Two isocaloric and isoproteic diets (35% crude protein) were formulated, one with the inclusion of the immunostimulant functional mixture (40 kg·t−1), composed of 150 mg·kg−1 of nucleotides, 1000 mg·kg−1 of β-glucans, 1000 mg·kg−1 of ascorbic acid (vitamin C), and 20 mg·kg−1 of alpha-tocopherol (vitamin E), and another without. The combined supplementation of nucleotides, β-glucans, ascorbic acid, and alpha-tocopherol resulted in a 59.95% increase in final weight, 64% weight gain, 66% daily gain, a 21.31% decrease in feed conversion rate, and double the retention of body protein. Supplementation also improved intestinal morphology and modulated the intestinal microbiome, increasing Chao-1 diversity. Transmission electron microscopy confirmed that fish fed with both diets exhibited intact intestinal mucosal membranes. Supplementation did not alter the hematological and immunological parameters, suggesting that there was no overstimulation of the fish’s immune system. This work allows us to evaluate the effect of reducing the use of animal protein in the diets of fish, along with the effects of nucleotides, β-glucans, ascorbic acid, and alpha-tocopherol. Together, these compounds can provide fish with the necessary tools to achieve optimal health and growth.