Search

The use of fish meal/oil in carnivorous fish feeds remains a concern for the environmental sustainability of aquaculture. In this study, we investigated the impact of an innovative diet designed to be cost‐effective and environmentally sustainable (i.e., 60% replacement of fish meal by a blend of plant, yeast [Saccharomyces cerevisiae], and krill meal feed ingredients) on the growth, health, and welfare of gilthead seabream (Sparus aurata). Over a 135‐day experiment, fish were fed either the innovative or a commercial diet (control), and various parameters were evaluated, namely growth performance, levels of physiological blood parameters related to stress, immunity, health, and welfare, as well as swimming activity, serving as a proxy for energy expenditure. Results revealed that the innovative diet enhanced growth compared to fish fed the control diet. Hematological and biochemical indicators did not highlight any impaired welfare condition in fish fed innovative diet while higher levels of Immunoglobulin M were measured in plasma of fish fed innovative diet, potentially suggesting enhancement of humoral immunity. However, accelerometer tags data revealed that fish fed the innovative diet exhibited higher overall swimming activity, suggesting higher energy expenditure, which was consistent with greater prealbumin levels measured in the plasma. In conclusion, the higher energy metabolism in fish fed the innovative diet might be compensated by the diet's content, which may boost humoral immunity and hence help the fish develop a better adaptation to rearing environment, including its viral and bacterial load, ensuring overall better growth. Longer term investigations, including measurements of additional parameters, are required to validate these promising preliminary outcomes. [ABSTRACT FROM AUTHOR]

In the past decade, insect meal has gained popularity in the animal feed industry, particularly in aquafeed, due to rising costs and decreased availability of fish meal (FM) and fish oil. Initially met with skepticism, insect meal is now seen as a promising ingredient because of its high nutrient profile. Research worldwide is exploring its potential as a FM replacement. Insects are abundant, nutritious, and environmentally friendly, as they can be reared on organic waste, minimizing the need for land, water, and energy. This research aims at obtaining a comprehensive and in‐depth understanding of the current status and research trend patterns in this research field. To achieve this goal, this study conducts a mini systematic review and scientometric analysis of the global research published from 2013 to 2022 on the usage of insect meal in aquaculture. In the scientometric analysis, a total of 354 papers published by 1800 authors in 124 different journals from the Web of Science (WoS) core collection were analyzed, evaluating the number of publications, most relevant authors, organizations, top cited countries, most globally cited publications, and trending research themes in this field. The result showed that the University of Turin was the leading organization in insect meal research, whereas aquaculture was the leading journal, and author Laura Gasco was the prominent researcher in this field in the studied time frame (2013–2022). Italy was the leading country in Europe, while China dominated Asia in terms of the number of publications. The annual growth rate in insect meal research was found to be positive (23.11%), with 36.95 average citations per document. This study helps practitioners and scholars understand the current state of insect meal in aquaculture and identifies research requirements that can benefit both academia and industry. [ABSTRACT FROM AUTHOR]

Simple Summary: This experiment was conducted in accordance with the prevailing trend of identifying alternative sources of nutrition to compensate for the economic shortcomings of fish meal in the aquaculture industry. The experiment employed soybean-based concentrated protein, which is approximately half the cost of fish meal, and focused on investigating its impact on growth and physiological processes. Three experimental diets were prepared: the control diet (Con) contained 60% FM, and the experimental diets contained 25% (SPC25) and 50% (SPC50) FM replaced by SPC. Following the 140-day feeding period, no significant differences in growth performance were observed. However, an increase in the replacement rate was associated with a reduction in stress and immune sensitivity, while the SPC25 treatment exhibited elevated levels of digestive enzyme-related genes. Therefore, substituting 25% FM with SPC was most effective for commercial fish farming. This study identified the effects of substituting fishmeal (FM) with soy protein concentrate (SPC) supplemented with lysine and methionine in the olive flounder (Paralichthys olivaceus) diet on the expression of genes related to growth, stress, immunity, and digestion. Three experimental diets were prepared; the control diet (Con) contained 60% FM, and the experimental diets contained 25% (SPC25) and 50% (SPC50) FM replaced by SPC. After the 140-day feeding period, weight gain, specific growth rate, feed availability, biological indices, and chemical composition of the muscle were not significantly affected by the dietary treatments. The gene expression levels of growth-related genes (IGF, GFB-3), immune-related genes (IL-8 and caspase), and stress-related genes (SOD, GPX, PRX, TRX) were higher in Con fish than in those fed the SPC25 and SPC50 diets. Chymo-TRY2, TRY2, and TRY3 in the stomach of fish fed the SPC25 diet were higher than fish fed the Con or SPC50 diets. TRY2 and lipase of fish fed the SPC25 diet were higher than those of fish fed the other diets but TRY3 was not significantly affected by the treatments in the intestine. In conclusion, substituting 25% FM with SPC was the most effective diet for the expression of growth, immune, stress, and digestive enzyme genes. [ABSTRACT FROM AUTHOR]

Simple Summary: Glycerol monolaurate, known for its strong antimicrobial properties, is a chemical compound formed by the combination of lauric acid and glycerol. This research focused on how glycerol monolaurate affects the growth, digestive enzyme activity, immune system, blood antioxidant level, and intestinal structure of black sea bream. This research could contribute to raising healthier aquatic animals, potentially reducing both the costs and environmental impact associated with aquaculture. These findings suggest that glycerol monolaurate may be the most suitable dietary supplement for fish; however, further research on its effect on the gut microbiota and gene expression is still required. An eight-week feeding trial was conducted to examine the impact of dietary supplementation with glycerol monolaurate (GML) on juvenile black sea bream. A basal diet was formulated containing 24% fish meal, while five additional diets were prepared, each supplemented with varying levels of GML: GML1 (0.01%), GML2 (0.02%), GML3 (0.04%), GML4 (0.08%), and GML5 (0.16%). Triplicate tanks were randomly allocated to each diet, each containing 20 fish with an initial weight of 1.55 ± 0.05 g. By the trial's end, the GML3 group displayed a notably higher final body weight (FBW), weight gain (WG), specific growth rate (SGR), and protein efficiency ratio (PER) compared to the other groups (p < 0.05), but the FCR was significantly higher in the control group. However, no significant differences were observed in the MFI, PPV, CF, HSI, IPF, VSI, or SR among the groups (p > 0.05). Regarding the proximate compositions of the dorsal muscle and whole body, no substantial differences were observed across the groups (p > 0.05). Additionally, there were no significant variations in digestive enzyme activity (p > 0.05), serum immune, or biochemical parameters in the midgut and hindgut among the treatment groups. But in the serum immune response IgM, C3 and C4 were significantly higher in the GML3 group as compared to the other groups (p < 0.05). However, the GML3 group exhibited significantly greater fore-intestinal villus height, crypt depth, villus height per crypt depth, and the number of goblet cells per villus compared to the other groups (p < 0.05). Overall, GML supplementation, particularly GML3, significantly improved growth indicators like the final body weight and intestinal morphology. While certain parameters remained unaffected, these findings suggest GML's potential as a beneficial dietary supplement in fish diets. [ABSTRACT FROM AUTHOR]

Fish feed is critical in aquaculture production, accounting for over 60% of operational costs, with protein being the most expensive component. Traditionally, fish meal (FM) has been the primary protein source. However, due to declining capture fisheries and high demand, FM has become scarce and costly, necessitating the search for alternative, low‐cost, and nutritionally balanced protein sources. A 180‐day feeding experiment was conducted to evaluate the effects of replacing FM with a combination of cottonseed and sunflower meal (SFM) in Nile tilapia diets on growth performance, protein digestibility, and economic returns. Freshwater shrimp meal was replaced at 25%, 50%, 75%, and 100% (diets D1, D2, D3, and D4) and compared to the control diet (D0) containing only FM. Monosex Nile tilapia fingerlings (25 ± 0.01 g) were allocated to 15 cages within an 800 m2 earthen pond. Fish on diets D0 and D1 showed superior growth performance metrics, including final mean body weight, weight gain, daily weight gain, specific growth rate, feed conversion ratio, and survival rate (p > 0.05), compared to diets D2, D3, and D4. Growth performance declined significantly with increasing levels of the plant protein mixture (p < 0.05). Diet D0 had the highest apparent protein digestibility, while D4 had the lowest. Cost‐benefit analysis revealed that diet D0 had the highest production cost, followed by diets D1, D2, D3, and D4, with no significant cost difference between D0 and D1 (p > 0.05). Thus, the plant protein mixture can effectively replace FM at a 25% inclusion level in Nile tilapia diets. [ABSTRACT FROM AUTHOR]

Fish meal (FM) is an essential ingredient in fish feeds, but the thermal treatments used during its production might affect its nutrient availability. Therefore, an in vivo digestibility trial was conducted with three different thermal treated FM, at no heat treatment (control), 70, and 140 °C. A total of 216 rainbow trout (230 ± 6.0 g) were randomly assigned to 12 tanks, and feces samples were collected by stripping. FM was produced by lyophilizing mackerel. The lyophilized FM (94% DM) was then divided into three groups: FM Control, which was not exposed to thermal treatments, and FM 70 °C and FM 140 °C, which were exposed for 1 h to the respective temperatures of its descriptions. A conventional FM-based (FM with 64% CP produced at 110 °C) control diet was used as a basal diet. In the experimental groups, 30% of the basal diet was replaced by one of the tested FMs. No differences in apparent total tract digestibility (ATTD) were observed between FM Control and 70 °C. Protein ATTD of FM 140 °C as well as Arg ATTD were lower compared to FM Control and 70 °C. The same effect was observed for His and Asp ATTD. The current study showed that thermal treatment affects FM macronutrient and amino acid ATTD. [ABSTRACT FROM AUTHOR]

This study investigated the effect of partially replacing fish meal with krill and copepod meals in inert diets co-fed with shrimp on the growth and nutrient digestibility of long-snout seahorses (Hippocampus guttulatus). A control diet (Diet 1) using raw starch and four experimental diets with similar protein (≈44.8%) and energy (≈15.1 MJ/kg) levels were tested. Diet 2 used fish meal as the sole protein source, while in Diets 3–5, krill and copepod meals replaced 44% of the fish meal. Seahorses fed shrimp + Diets 2–5 showed significantly higher growth rates (p < 0.05) than those fed shrimp + Diet 1, though there were no significant growth differences among Diets 2–5. Digestibility of dry matter (46.1% to 72.2%), lipids (73.3% to 85.5%), crude protein (89.8% to 95.8%), energy (82% to 92.2%), and phosphorus (28.7% to 64.4%) varied with diet, being consistently lower in seahorses fed shrimp + Diet 1. As an agastric species, H. guttulatus did not exhibit impaired digestibility for any of the tested nutrients, minerals, or energy. This study suggests that crustacean meals can effectively substitute fish meal in inert diets for this species, contributing to the sustainability and optimization of captive seahorse husbandry practices. [ABSTRACT FROM AUTHOR]

Simple Summary: Providing high-quality feeds is required to maintain goat kids' health and improve their growth performance during their early growth phase, such as milk protein, fish meal, or extruded feed. The present study demonstrates that supplementation with 2% fermented feather meal–soybean meal product in the diet can promote the growth of goat kids by improving crude protein digestibility, diarrhea status, and immunity: therefore, it can completely replace the fish meal as a starter. These findings provide potential for practices of nutrition and immunity in goat kids, benefiting the livestock industry. This study investigates the effects of replacing fish meal with fermented feather meal–soybean meal product (FFSMP) from Bacillus amyloliquefaciens CU33 in the starter on growth performance, relative health performance, and digestibility of Alpine goat kids. In trial 1, thirty-two Alpine goat kids (male) were randomly assigned to dietary supplementation of 2% feather meal–soybean meal mix (FSM), 2% fish meal, or replacing fish meal with 50% or 100% FFSMP (FFSMP-50 or FFSMP-100) in starter (n = 8). In trial 2, sixteen goat kids were selected after trial 1 and used in this digestion trial which began from 12 weeks old. The treatments were the same as in trial 1 (n = 4). In trial 1, the growth performance of the FFSMP groups was better than the FSM group at 0 to 10 weeks (p < 0.05). The fecal consistency index of the FFSMP-100 group was better than the FSM group at 0 to 5 weeks and 5 to 10 weeks. In trial 2, the crude protein (CP) digestibility of the FSM group decreased (p < 0.05). In conclusion, dietary supplementation with 2% FFSMP in goat kids' diets can improve the growth performance, the CP digestibility, and diarrhea status, and it can completely replace the fish meal in starter diets. [ABSTRACT FROM AUTHOR]

The aim of this study was to reveal the effects of yeast culture replacing fish meal (FM) or chicken meal (CM) on the growth performance, serum biochemical indexes, intestinal digestive enzyme activities, hepatic antioxidant, and hepatic and intestinal histology of bullfrog (Lithobates catesbeianus). The basal diet contained 100 g/kg FM and 100 g/kg CM, and then yeast culture was used to decrease FM or CM level to 75 and 50 g/kg with yeast culture inclusion of 32 and 64 g/kg, respectively, resulting in five groups of isonitrogenous diets (control, FM75, FM50, CM75, and CM50). A total of 450 bullfrogs (45.5 ± 0.4 g initial weight) were fed the five diets for 50 days. (1) The FM50 group presented significantly lower weight gain, condition factor, hind leg index, and higher feed conversion ratio than the control group, while the other three groups of FM75, CM75, and CM50 showed no significant difference in growth performance when compared to the control group. (2) The serum triglyceride content of FM50 group was significantly lower, while the alkaline phosphatase activity was significantly higher than those of the control group. The serum total cholesterol levels were significantly lower in the CM50 group compared to the control group. (3) In intestinal digestive enzyme activities, the trypsin and α‐amylase activities in the CM75 and CM50 groups, the trypsin activity in the FM75 group, and lipase activity in the CM50 group were all significantly higher than those in the other groups. (4) The replacement of 50% FM with yeast culture (FM50 and CM50 groups) promoted the total antioxidant capacity in the liver, but compared to the control group, the intestinal villi height and muscularis propria thickness in the FM50 group were significantly lower. There was no difference (P > 0.05) in liver histology among all the groups. In conclusion, in a basal diet containing 100 g/kg FM and 100 g/kg CM, 32.0 and 64.0 g/kg yeast cultures could successfully replace 25% of dietary FM and 50% of dietary CM without negative effects on the growth performance, serum biochemical indexes, and hepatic and intestinal health of bullfrogs. [ABSTRACT FROM AUTHOR]

The fast growing of the aquaculture sector increases the need for natural feed substances such as insects. The present study was carried out to address the effects of replacing fish meal with black soldier fly larvae meal (BSF) supplemented with ginger powder (GP) in feed on the survival, growth performance, and muscle composition of the African catfish pre-adults. A total of 945 fish were randomly divided into 7 groups of 60 Clarias gariepinus (156±15g/fish) with 3 replications, and placed in 21 plastic tanks with a capacity of 0.6m3. Seven isonitrogenous diets were formulated. Three treatments represented the group of individuals fed with diets substituted at 70%, 85%, 100% BSF, respectively, while the other three treatments followed the same levels of substitutions but with the addition of 1% GP, and the last treatment represented the control experiment with 100% fish meal. At the end of the trial, three individuals (850±50g/fish) were randomly selected per treatment and were used for the bromatological analysis. The results show that the survival rate was comparable in all treatments (P>0.05), and the fish fed with 100%BSF + 1%GP exhibited the best survival rate. The growth and nutrient utilization characteristics were not significantly influenced whatever the treatment, with the exception of the consumption index, which was higher in fish fed with 100%BSF+ 1%GP during the growth stage. The evolution of weight gain was generally comparable during the experiment (P>0.05). The condition factor K was close to 1, implying the good health of the fish during breeding. The bromatological characteristics of the flesh indicate that the fish fed with 100%BSF+ 1%GP were comparable with the control and possessed a good nutritional value without negatively affecting the nutritional profile of the fish. Consequently, the replacement of 100% Hermetia illucens supplemented with 1% Zingiber officinale is recommended for the growth of Clarias gariepinus pre-adults [ABSTRACT FROM AUTHOR]

This study evaluated the anaesthetic potential of clove basil (Ocimum gratissimum) essential oil (EO-OG) in the post-larvae (PLs) of M. rosenbergii. The PLs were individually transferred to aquariums (500 mL) containing 50, 100, 150, 200, or 300 μL L−1 EO-OG. A sixth group of PLs was exposed to freshwater only, and a seventh group was exposed to the highest concentration of ethanol used to dilute EO-OG. Upon reaching the anaesthesia stage, the PLs were transferred to aquariums (500 mL) with freshwater only to evaluate the recovery time. The shortest sedation times were observed at 200 (15.98 s) and 300 μL L−1 (25.85 s). The shortest anaesthesia time was observed at 200 μL L−1 (22.52 s). The longest recovery time was observed at 100 μL L−1 (1367.10 s); the shortest recovery time was observed at 150 μL L−1 (630.10 s). No mortality or adverse effects were observed in any experimental group. The concentration of 150 μL L−1 resulted in sedation (49.24 s), anaesthesia (80.10 s), and recovery (630.10 s) times within those suggested as adequate for freshwater prawn farming. This research demonstrated the sedative and anaesthetic properties of EO-OG and its potential application in prawn farming. This study recommends using 150 μL L−1 of EO-OG in M. rosenbergii PLs. [ABSTRACT FROM AUTHOR]

This paper analyzes the factors influencing households' resilience capacities to shocks within Kenya's fisheries and aquaculture sectors and draws from primary data collected from 419 fish-dependent households across Kisumu, Busia, Mombasa, and Kilifi counties. The sample represents a total of 48,000 fishing households. The study adopted a quasi-longitudinal design and computed the household resilience capacity index (RCI) using the resilience index measurement and analysis (RIMA-II) model. The results indicate that male-headed households' mean household RCI scores (mean = 45.07 ± 10.43) were statistically significant to that of female-headed households (mean = 38.15 ± 9.25), suggesting that female-headed households are associated with lower resilience capacities than male-headed households. Moreover, the study identifies differences in resilience levels across various occupations within the sector. For instance, RCI scores among fish traders (mean = 40.71 ± 9.97), a function performed mainly by women, statistically differed (p < 0.005) from male-dominated cage farming (mean = 48.60 ± 10.47), whereas RCI scores at the production level for fisher folks (mean = 44.89 ± 10.09) and pond farmers (mean = 44.04 ± 12.07) showed no statistical difference (0 > 0.05. Additionally, households with more income sources tend to have higher resilience capacities. Seasonality in fishing cycles limited households' ability to recover from climate-induced shocks; the more months without fishing activity, the less the odds of recovery from shocks (OR = 0.532, 95% CI [0.163, 0.908], p = 0.022). Furthermore, households that lacked guaranteed market access and inputs during COVID-19 were less likely to recover during and after the shocks (OR = 0.401, 95% CI [0.161, 0.999], p = 0.05). Households organized in cooperatives with better access to credit showed a higher chance of recovery. The study recommends (a) adopting gender-sensitive approaches in fisheries and aquaculture interventions to empower women in trade, (b) strengthening policies to enhance access and adoption of climate-smart technologies such as cage fish farming, (c) promoting livelihood diversification to sustain households' income during fishing off-seasons, and (d) enhancing market linkages in the fish value chain through coordinated producer organizations. Further research should explore the possibilities of introducing index-based weather insurance and other tested suitable safety nets for the fisheries and aquaculture sector. [ABSTRACT FROM AUTHOR]

Motile aeromonad septicemia (MAS), caused by the Aeromonas species, has been a serious problem in fish health management, particularly in Nile tilapia (Oreochromis niloticus). This study characterized an Aeromonas species isolated from farmed tilapia fingerlings in Binangonan, Rizal, Philippines, and tested for its pathogenicity in tank trials. The isolate, designated as Aeromonas veronii DFR01 (Diseased Fish Rizal), was identified based on 16S rRNA phylogenetic analysis, 16S rRNA homology, and MALDI-TOF mass spectrometry. Its biochemical profile was generated from API and Biolog Gen III systems. A median lethal dose of A. veronii DFR01 was determined to be 107 CFU/mL in tank trials and was utilized as a whole-cell inactivated antigen for oral vaccine development. The immunized tilapia fingerlings produced elevated levels of immunoglobulin M (IgM) in the blood as determined by an enzyme-linked immunosorbent assay (ELISA). There was a significant increase in IgM levels 14 days post-vaccination. A quantitative polymerase chain reaction (qPCR) showed increasing levels of IgM gene expression after vaccination until 38 days of culture. Vaccinated fish showed 25–35% cumulative mortality after the challenge, while non-vaccinated-challenged fish showed 75% mortality. The findings of this research suggest that the fish oral vaccine may prove beneficial for farmed tilapia populations. The vaccine elicited improved immune responses in the fish and resulted in higher survival rates. [ABSTRACT FROM AUTHOR]

This study compared the effects of three supplementary diets—egg yolk, Artemia, and commercial pellets with 48% crude protein—on the growth performance and survival rate of redbreast tilapia (Coptodon rendalli) under intensive culture conditions at the Kamutjonga Inland Fisheries Institute in the Kavango East region of Namibia. The study was conducted from December 2023 to January 2024 using a complete randomized design replicated thrice. Results showed that fish fed with commercial pellets exhibited the highest specific growth rate (1.39 ± 0.80%) compared to egg yolk (0.94 ± 0.54%) and Artemia (0.33 ± 0.19%). Commercial pellets also had the best survival rate (76.19 ± 43.099), compared to egg yolk and Artemia (70.47 ± 40.69; 33 ± 19.05), respectively. However, egg yolk had the best feed conversion ratio (0.20 ± 0.05) compared to the commercial pellets (0.22 ± 0.04) and Artemia (0.26 ± 0.07). Critical water quality parameters were maintained within acceptable survival ranges for C. rendalli across all treatments. These findings highlight the importance of dietary protein content in optimizing the growth and survival of C. rendalli under intensive culture conditions and provide insights for effective feeding strategies. However, commercial pellets are expensive and inaccessible to small-scale fish farmers. As an alternative, egg yolk emerged as a viable and affordable feed option, promoting fish growth and supporting the establishment of small-scale farming practices in the region. [ABSTRACT FROM AUTHOR]

Despite the huge potential of aquaculture in the Amazon, several producers have abandoned the activity due to a lack of assistance, technology, and innovation. Thus, the objective of this study was to identify factors that have contributed to the withdrawal of aquaculturists from the municipality of 'Vigia de Nazaré', state of Pará (Northern Region of Brazil). This case study took place in 2022 through a quanti-qualitative survey, applying structured questionnaires to former aquaculturists. A total of 30 fish farms were investigated, with 11 of them being abandoned. They are distributed across 10 rural communities that have developed fish farming, with 'Vila de Itapuá' (18.2%) being the most representative. When active, fish farming was practiced by men (100%) aged between 51 to 60 years (54.5%) with an incomplete primary education (100%), who carried out the activity for an average of 5 years (81.8%), quitting fish farming between the years 2019 and 2020 (72.7%). All former aquaculturists owned small properties, with excavated ponds in an extensive system and used family labor. The absence of technical assistance and the high cost of feed were pointed out as the main problems in the production chain. It is worth noting that the monoculture of Tambaqui (Colossoma macropomum) accounted for 63.6% of the species produced in rural communities. In conclusion, former aquaculturists express the desire to return to fish farming due to its socio-economic importance. For this, government actions supporting technical assistance and advanced studies in fish nutrition by educational, research, and extension institutions are necessary. [ABSTRACT FROM AUTHOR]

This study aimed to determine the protein requirements of the fattening phase for Nile tilapia (Oreochromis niloticus) fed fish meal-free diets. A total of 75 Nile tilapia were maintained in a water recirculation system, and five isoenergetic diets were formulated with increasing protein levels encompassing three repetitions each. The findings revealed that protein levels significantly affected (p < 0.05) certain Nile tilapia performance, yield, and composition parameters. The determined parameter values clearly indicated that Nile tilapia can be fed fish meal-free soybean meal and corn-based diets. Furthermore, the metabolic plasticity of this species concerning dietary protein concentrations was also demonstrated, with adequate performance results achieved in treatments containing from 267 to 294 g/kg digestible protein (DP), or 298 to 327 g/kg crude protein (CP), where the balance between essential and non-essential amino acids and energy resulted in adequate performance correlated to satisfactory feed conversion values and filet yields and composition. A DP concentration of 267 g/kg (298 g/kg CP) is recommended when offering corn and soybean meal-based diets during the Nile tilapia fattening phase to fish weighing between 400 and 700 g. [ABSTRACT FROM AUTHOR]

This experiment was conducted to determine total amino acid (AA) content and standardized ileal digestible (SID) amino acid content of 6 different origins of fish meal (FM) and subsequently determine equations that estimate total and SID amino acid contents from chemical composition as well as SID amino acid contents from its total AA. In order to conduct this study, a total of 210 one-day-old male broiler chicks were randomly assigned to 7 dietary treatments consisting of 6 semi-purified diets containing each of FM as the only source of dietary protein (200 mg of crude protein/g diet) and one nitrogen-free diet in order to determine ileal endogenous amino acids (IEAA) flow. Birds were allowed ad libitum access to a corn-soybean meal starter diet until ten days, a grower diet from 11 to 23 days, and then experimental diets from 24 to 28 days of age. The total content of Lys and Met among the various samples significantly differed from 1.52 to 2 and 0.59 to 0.77%, respectively (P < 0.05). This difference was observed among the other total and SID amino acids. In this study the accuracy and precision of the models were tested by the adjusted coefficient of determination (R2) value, P-value regression coefficients, and standard error of prediction (SEP). The SEP of the developed regression equations for the predicting SID amino acids of FM were from 0.009 (for Met) to 0.056 (for Arg). [ABSTRACT FROM AUTHOR]

This experiment was conducted to determine total amino acid (AA) content and standardized ileal digestible (SID) amino acid content of 6 different origins of fish meal (FM) and subsequently determine equations that estimate total and SID amino acid contents from chemical composition as well as SID amino acid contents from its total AA. In order to conduct this study, a total of 210 one-day-old male broiler chicks were randomly assigned to 7 dietary treatments consisting of 6 semi-purified diets containing each of FM as the only source of dietary protein (200 mg of crude protein/g diet) and one nitrogen-free diet in order to determine ileal endogenous amino acids (IEAA) flow. Birds were allowed ad libitum access to a corn-soybean meal starter diet until ten days, a grower diet from 11 to 23 days, and then experimental diets from 24 to 28 days of age. The total content of Lys and Met among the various samples significantly differed from 1.52 to 2 and 0.59 to 0.77%, respectively (P < 0.05). This difference was observed among the other total and SID amino acids. In this study the accuracy and precision of the models were tested by the adjusted coefficient of determination (R2) value, P-value regression coefficients, and standard error of prediction (SEP). The SEP of the developed regression equations for the predicting SID amino acids of FM were from 0.009 (for Met) to 0.056 (for Arg).

Background: Fish bone ingestion is commonly encountered in emergency department. It poses a diagnostic and therapeutic challenge particularly when it migrates extraluminally, necessitating a comprehensive and multidisciplinary approach for successful management. Case presentation: Here we reported four cases of extraluminal fish bone. The first patient was a 68-year-old Chinese man who had odynophagia shortly after a meal involving fish. The second was a 50-year-old Iban man who reported a sharp throat pain after consuming fish 1 day prior. The third patient was a 55-year-old Malay woman who developed throat pain and odynophagia after consuming fish 1 day earlier. The fourth patient, a 70 year-old Iban man, presented late with odynophagia, neck pain, swelling, and fever 1 week after fish bone ingestion. These unintentional fish bone ingestions faced challenges and required repeat computed tomography scans using multiplanar reconstruction in guiding the surgical removal of the fish bone. Conclusion: We underscore the significance of multiplanar reconstruction in pinpointing the fish bone's location, demonstrating the migratory route, and devising an accurate surgical plan. [ABSTRACT FROM AUTHOR]

A 12-week growth trial was conducted to evaluate the complete coreplacement of fish meal (FM) and fish oil (FO) in juvenile Florida pompano (Trachinotus carolinus) diets. Five open-formula experimental diets were formulated as iso-nitrogenous (approximately 46% crude protein) and isolipidic (approximately 15% crude lipid). It is assumed that Florida pompano lack the mechanisms for synthesizing sufficient LC-PUFA. In the FM/FO-free diets, to meet the necessary dietary intake of LC-PUFA, a commercially available Schizochytrium algal oil was used. Four diets were prepared from a basal mix, with spirulina and poultry by-product meal as the principal protein sources. They differed only in their oil source, containing fish oil (FO), algal oil (AO), soy oil (SO), or a 50/50 blend of algal oil and soy oil (A/S). The fifth experimental diet (control) was a standard open-formula FM diet. In addition to the experimental diets, two commercial closed-formula diets served as references. The seven diets, each with four replicates, were stocked with 20 Florida pompano (approximately 4 g) in each. The experimental open-formula diets were tested against the control using Dunnett's t-test, and different oil sources were tested against each other using orthogonal contrasts. The four experimental diets were each tested against the two reference diets with equivalency tests. Feed intake and survival were not different between the experimental diets and control. However, all production metrics were lower in the SO diet than the control. No other differences were observed between the FO, AO, and A/S diets and the control, or between the three diets. The feed conversion ratio (FCR) was higher in fish fed the SO diet than in fish fed the control diet, and no other differences were found. The protein efficiency ratio (PER) was higher in fish fed the control diet than in fish fed the experimental diets. Protein productive values (PPV) were similar to PER, except that the PPV in fish fed the AO diet was not different from the control. The contrasts revealed that the FO, AO, and A/S diets resulted in a lower FCR than the SO diet. The PER was higher in fish fed the AO diet, and lower in fish fed the SO diet. The PPV was higher in fish fed the AO diet than in fish fed the A/S and SO diets, but similar to that of fish fed the FO diet. There were striking differences in performance between the two commercial reference feeds, underscoring the importance of using well-defined open-formula diets as a reference or control. To our knowledge this is the first study to demonstrate that co-replacement of FM and FO can be achieved in Florida pompano by supplying an FM- and FO-free diet. The development of successful open-formula diets without FO will help spur innovation and sustainability in aquaculture production. [ABSTRACT FROM AUTHOR]

Aquaculture production is continuously increasing, consequently increasing the demand for feed. Unfortunately, the reliance on fish meal and fish oil also raises sustainability issues due to overfishing and resource depletion. Nanoparticle-enhanced feed presents a promising solution to these challenges. Nanoparticles, with their large surface area-to-volume ratio and encapsulation capabilities, significantly improve nutrient delivery, absorption, and utilization, enhancing growth and health. Their immune-modulatory and antimicrobial properties reduce antibiotic use and support sustainability. This review explores different nanoparticles in fish feed, including metal-based, non-metal-based, and composite types, each offering benefits for fish growth and health. It highlights the advantages of nanoparticle-enhanced feed, such as improved nutrient delivery, immune enhancement, antimicrobial action, stress reduction, and environmental sustainability. Concerns like potential toxicity, safety, bioaccumulation, and environmental impacts of nanoparticles, together with measures of addressing these concerns, are also highlighted. The review concludes with insights into future research directions. [ABSTRACT FROM AUTHOR]

Simple Summary: Cholecystokinin (cck) is an important factor in regulating feed intake. According to a previous study, replacing fish meal (FM) in the diet of largemouth bass could downregulate the expression of the cck gene; however, the underlying regulatory mechanism remains unclear. Therefore, we investigated the effect of cck on feed intake and its potential mechanism of action via injecting exogenous CCK peptide and its receptor antagonist. This study's results indicate that cck could regulate the feed intake of largemouth bass through regulating feeding-related genes in the brain and intestine. Furthermore, cck required binding with the receptor to inhibit feed intake more effectively in largemouth bass, and the binding effect of cholecystokinin receptor 1 (CCK1R) was better than that of cholecystokinin receptor 2 (CCK2R), which could lay a theoretical foundation for the study of fish feeding regulation. This study investigated the role of cholecystokinin (cck) in the feeding regulation of largemouth bass (Micropterus salmoides) via peptide activation and antagonist inhibition. The results show that the cck gene was expressed in various tissues, with the highest expression level occurring in the brain. Feeding, continuous feeding, and refeeding after fasting could significantly improve the mRNA levels of cck in the brain. Moreover, the activation of cck via injecting an exogenous CCK peptide could inhibit feed intake by regulating the mRNA levels of anorexigenic and feed-promoting factors in the brain and intestine. Furthermore, the CCK peptide reduced feed intake; however, the presence of an antagonist (Ly225910-CCK1R and devazepide-CCK2R) could reverse this effect through regulating the mRNA levels of anorexigenic and feed-promoting factors in the brain and intestine. Treatment with devazepide + CCK (CCK2R) reversed feed intake more effectively than Ly225910 + CCK (CCK1R) treatment. In summary, cck could regulate the feed intake of largemouth bass through regulating feeding-related genes in the brain and intestine. In addition, cck required binding with the receptor to inhibit feed intake more effectively in largemouth bass, and the binding effect of CCK1R was better than that of CCK2R. [ABSTRACT FROM AUTHOR]

The aquaculture sector is facing the challenge of developing sustainable and cost-effective alternatives to traditional fish feed components. Lupin, a versatile utilitarian legume, has garnered increasing interest due to its nutritional value, desirable effects on the environment, and economic feasibility. Lupin for its high protein content, balanced amino acid profile, ease of processing, its implications in livestock development and health, and potential means of reducing the industry ecological footprint has made it a potentially advantageous aquafeed ingredient. This review explores the promising nature of lupin in aquaculture, focusing on its nutritional value, digestibility, and impact on fish health and growth. The review also discusses at recent discoveries, challenges, and potential breakthroughs to provide insight into how lupin might advance the development of sustainable aquaculture techniques. [ABSTRACT FROM AUTHOR]

Simple Summary: Fishmeal is a vital protein in aquafeed; however, its high cost and limited availability pose significant challenges. This study investigates the efficacy of chicken meal, an animal protein with a higher yield and lower cost, as a substitute for fishmeal. After feeding bullfrogs with different feed formulations for eight weeks, it was found that replacing 50% of fishmeal with chicken meal increased the survival rate of bullfrogs, thus enhancing their overall weight. Additionally, this partial substitution improved the antioxidant capacity and intestinal digestive enzyme activity of the bullfrogs. Conversely, a 100% replacement of fishmeal showed no significant effect on survival rate and resulted in reduced weight gain and lower amino acid content in muscle tissues, indicating that complete replacement is unsuitable. In pursuit of sustainable aquaculture, this study was performed to evaluate chicken meal as a substitute for fishmeal in bullfrog diets. Three experimental groups were established: a control group (FM) with 20% fishmeal, a CM50 group with 50% replacement (10% fishmeal), and a CM100 group with 100% replacement (0 fishmeal). Bullfrogs were fed for 56 days. The CM50 group exhibited significant increases in total weight gain and survival rate and a notable decrease in feed coefficient (p < 0.05). However, the CM100 group showed contrary effects. Increasing chicken meal substitution correlated with decreased amino acid content in muscle. Notably, the CM50 group demonstrated enhanced activities of antioxidant enzymes (CAT, T-AOC) and elevated gene expression levels (cat, sod, gst, etc.) in muscle and the intestine (p < 0.05), improved intestinal morphology, enhanced digestive enzyme activities (amylase, lipase), and reduced expression of inflammatory factors (il-1β, il-8, il-17, etc.). Conversely, the CM100 group's indicators regressed to levels similar to or worse than those of the FM group. Therefore, a 50% substitution of fishmeal with chicken meal effectively promoted bullfrog survival, protected the intestines, and enhanced antioxidant capacity, supporting its potential as a fishmeal alternative. However, the adverse outcomes of the CM100 strategy, including growth retardation and reduced amino acid content in muscle, indicate that complete replacement is unsuitable. [ABSTRACT FROM AUTHOR]

Simple Summary: Fish meal (FM) is considered the primary protein source in fish feed, but the most expensive ingredient, which ultimately increases feed cost. Application of a substitute for FM in fish feed can lower feed cost, but it commonly leads to reduced palatability and lowered feed consumption of fish. Jack mackerel meal (JMM) has been reported to be an effective attractant and/or stimulant in the olive flounder diet. This study revealed that inclusion of 50% jack mackerel meal (JMM) at the expense of FM in the olive flounder (Paralichthys olivaceus) diet replacing 50% FM with duck by-product meal (DBM) lowered feed cost, but improved feed consumption and growth performance and economic return to the farmer. The results of this study will help olive flounder producers to improve their profitability. This experiment was performed to evaluate the inclusion impact of various levels of jack mackerel meal (JMM) in olive flounder (P. olivaceus) feeds substituting 50% FM by duck by-product meal (DBM) on growth, feed availability, and economic efficiency. Seven experimental diets were prepared. The control (Con) diet contained 60% FM. Fifty percent FM in the Con diet was substituted with DBM, and then the graded levels (0%, 10%, 20%, 30%, 40%, and 50%) of JMM were added instead of FM, named the DJ0, DJ10, DJ20, DJ30, DJ40, and DJ50 diets, respectively. All feeds were assigned to triplicate fish groups. At the end of 56 days' feeding, fish fed the DJ40 and DJ50 diets exhibited comparable weight gain and specific growth rate to fish fed the Con diet. Higher feed consumption was observed in fish fed the Con, DJ40, and DJ50 diets compared to fish fed the DJ0 and DJ10 diets. Lower feed conversion ratio was observed in fish fed the Con diet compared to fish fed the DJ0, DJ10, DJ20, and DJ30 diets. Furthermore, the DJ50 diet led to the highest economic profit index (EPI). In conclusion, inclusion of 50% JMM in the olive flounder diet replacing 50% FM with DBM seems to be the most recommendable dietary treatment based on growth and feed consumption of olive flounder and EPI. [ABSTRACT FROM AUTHOR]

Simple Summary: The present study shows how different combinations of eco-efficient ingredients can be considered reliable solutions for European aquaculture production. For this purpose, three different formulations were designed and tested in a 77-day gilthead sea bream trial. All diets supported similar growth rates, but the diet without poultry meal and processed animal proteins as the main fish meal replacer (NOPAP diet) shaped better nutrient utilization with an overall improvement of biomarkers of physiological condition. Such an integrative approach contributes to better understanding of what could be the best and least-cost feed formulation for an effective balance of sustainability and aquaculture profitability in a scenario of intensive aquaculture production and limited availability of marine feed ingredients for fish production. The growth of the aquaculture industry requires more sustainable and circular economy-driven aquafeed formulas. Thus, the goal of the present study was to assess in farmed gilthead sea bream (Sparus aurata L.) how different combinations of novel and conventional fish feed ingredients supported proper animal performance in terms of growth and physiological biomarkers of blood/liver/head kidney. A 77-day feeding trial was conducted with three experimental diets (PAP, with terrestrial processed animal protein from animal by-products; NOPAP, without processed animal protein from terrestrial animal by-products; MIX, a combination of alternative ingredients of PAP and NOPAP diets) and a commercial-type formulation (CTRL), and their effects on growth performance and markers of endocrine growth regulation, lipid metabolism, antioxidant defense and inflammatory condition were assessed at circulatory and tissue level (liver, head kidney). Growth performance was similar among all dietary treatments. However, fish fed the PAP diet displayed a lower feed conversion and protein efficiency, with intermediate values in MIX-fed fish. Such gradual variation in growth performance was supported by different biomarker signatures that delineated a lower risk of oxidation and inflammatory condition in NOPAP fish, in concurrence with an enhanced hepatic lipogenesis that did not represent a risk of lipoid liver degeneration. [ABSTRACT FROM AUTHOR]

Introduction: Screening excellent bacterial strains for fermentation is the key to improving the nutritional value and bioavailability of soybean meal (SBM). This study investigated the application of Bacillus subtilis-fermented soybean meal (FSBM) on the feed of Pacific white shrimp (Litopenaeus vannamei). Methods: FSBM was used to replace 0%, 25%, 50%, 75%, and 100% fish meal, and the feeding trial was lasted for 8 weeks (initial weight: 0.9 g). Results and discussion: The amino acid profile in the whole shrimp body was tested. FSBM substitution only significantly reduced the content lysine in whole shrimp body, but increased the content of arginine. Fatty acid data showed that the content of n-6 PUFAs in whole shrimp was significantly increased by FSBM substitution. In muscle, FSBM substitution significantly reduced the content of MUFAs, but increased the content of PUFAs including C18:3n-3, C18:2n-6 and C20:4n-6. No hepatopancreas structure modifications appeared in the 25% group compared with the control group. Subsequently, we investigated the response patterns of different organs to FSBM substitution from antioxidant, endoplasmic reticulum stress and immunity. A high proportion of FSBM significantly reduced the content of GSH in hemolymph and hepatopancreas, while increased the mRNA expression of cat. FSBM substitution did not affect the activities of antioxidant enzymes in the intestine. However, the mRNA expression level of hsp70 in the intestine was significantly reduced by FSBM. In terms of immunity, the mRNA expression levels of lgbp and penaeidin in the hepatopancreas showed a significant linear increase trend. In muscle, high proportion of FSBM significantly increased the mRNA expression of imd. FSBM substitution did not significantly affect the expression of immune genes in the intestine. In terms of endoplasmic reticulum stress, FSBM substitution significantly increased the mRNA expression of eif2a in the hepatopancreas. In muscle, FSBM substitution inhibited the mRNA expression of bip. In the intestine, FSBM replacing 75% of fish meal significantly increased the mRNA expression of bip and ire1. In summary, this study indicated that when the fish meal content account for 40% in diets (dry weight), the screened Bacillus subtilis-FSBM can replace 25% of fish meal protein without reducing the antioxidant and immune abilities of shrimp. [ABSTRACT FROM AUTHOR]

Desalted anchovy bones (Engraulis encrasicolus) and argan cake are important sources of minerals and animal proteins. The objective of this study was to analyze the respective consequences of their addition to the diet of broiler chickens (Gallus gallus). Four groups, each containing 15 chickens, were organized according to the following factorial scheme: four feed treatments (including a control group) x five chickens per treatment x three repetitions (4x5x3). The groups were fed four different feed rations containing varying proportions of desalted anchovy bones (DAB) and argan cake (AC): T (0%DAB/0%AC), L01 (1%DAB/1%AC), L02 (2%DAB/2%AC), and L03 (3%DAB/3%AC). Results of the study revealed a significant difference (p>0.05) in weight gain during the start and end of the study for L02 (2144.46g), which was higher compared to the control T (2140.56g). Regarding the feed conversion ratio, L02 (1.54) was lower than the control T (1.65). Conversely, the other feed combinations, including 1% (L01) and 3% (L03), negatively affected weight gain and feed conversion ratio due to the addition of DAB and AC. From the results of the study, it can be concluded that at a low rate of 2% (L02: 2%DAB/2%AC), both desalted anchovy bones and argan cake appear to be effective substitutes for other fish meals and soybean cake in the diet of broiler chickens. [ABSTRACT FROM AUTHOR]

This study addressed the urgent need for sustainable protein sources in aquaculture due to the depletion of marine resources and rising costs. Animal protein sources, particularly poultry by-product meal (PBM) and insect exuviae meal, were investigated as viable alternatives to fishmeal (FM). The research study confirmed the successful replacement of FM with a combination of PBM and insect exuviae meal (up to 50%) in the diet of European seabass without compromising growth, feed conversion, gut health, and liver fat content. In particular, growth was robust with both PBM formulations, with the 25% PBM diet showing better results. Histological examinations showed good gut and liver health, contradicting the concerns of previous studies. This paper emphasizes the importance of holistic analyzes that go beyond growth parameters and include histomorphological investigations. The results show that PBM in combination with insect/exuviae meal is well tolerated by seabass, which is consistent with reports in the literature of it mitigating negative effects on gut health. A detailed analysis of the microbiota revealed a decrease in the Firmicutes/Proteobacteria ratio due to an increase in potentially pathogenic bacteria. However, the formulation containing insect exuviae partially counteracted this effect by preserving the beneficial Lactobacillus and promoting the synthesis of short-chain fatty acids (SCFAs), particularly butyrate. Chitin-rich components from insect exuviae were associated with improved gut health, which was supported by the increased production of SCFAs, which are known for their anti-inflammatory properties. This paper concludes that a combination of PBM and insect/exuviae meal can replace up to 50% of FM in the diet of seabass, supporting sustainable aquaculture practices. Despite some changes in the microbiota, the negative effects are mitigated by the addition of insect exuviae, highlighting their potential as a prebiotic to increase fish productivity and contribute to a circular economy in aquaculture. [ABSTRACT FROM AUTHOR]

The continuous growth of the aquaculture industry implies increased demand for efficient sources of aquafeed, such as fishmeal. Pelagic fish are a desirable source of fishmeal due to their high nutritional content. Nevertheless, several pelagic stocks that have been exploited extensively for fishmeal production face ecological limits due to commercial exploitation, and the aquaculture industry is now seeking novel, efficient, and sustainable sources of aquafeed. The mesopelagic zone, an ecosystem with many scientific uncertainties, is being considered as a potential source for fishmeal, largely owing to the abundance of mesopelagic fish and their robust nutritional profile. However, both the ecological and economic viability of commercial exploitation of mesopelagic fish are not yet well understood. To understand the conditions that would make such an endeavor economically viable in the context of global fishmeal production systems, we use a bioeconomic model that assesses the economic consequences of including mesopelagic fish as a fishmeal source. Through simulations, we assess the economic implications of this hypothetical mesopelagic fishery on major pelagic fishmeal production systems. The mesopelagic fishery can be economically profitable for harvesters, and its addition to global fishmeal production reduces fishmeal market price, thus making it more accessible to aquaculture farmers and less profitable for pelagic fishers. While this may reduce fishing pressure on pelagic forage‐fish stocks, the implications of commercial exploitation of mesopelagic on key ecosystem services remain a concern. Recommendations for Resource Managers: The continuous growth of the aquaculture industry implies increased demand for efficient sources of aquafeed, such as fishmeal.Several pelagic stocks that have been exploited extensively for fishmeal production face ecological limits due to commercial exploitation, and the aquaculture industry is now seeking novel, efficient, and sustainable sources of aquafeed.The mesopelagic zone is being considered as a potential source for fishmeal. However, both the ecological and economic viability of commercial exploitation of mesopelagic fish are not yet well understood.We use a bioeconomic model to assess the economic consequences of including mesopelagic fish as a fishmeal source and the economic implications of this hypothetical fishery on major pelagic fishmeal production systems.The results show that mesopelagic fishery could be profitable for harvesters, and its addition to global fishmeal production would reduce fishmeal market price, thus making it more accessible to aquaculture farmers and less profitable for pelagic fishers. [ABSTRACT FROM AUTHOR]

The main cost in aquaculture production is feed, so management practices and feeding strategies aim to optimize both feed intake and efficiency. This study aimed to evaluate the growth performance of beluga, Huso huso, affected by periodic changes in dietary protein sources and hence identify possible innovative feeding strategies toward more efficient use of dietary protein. This study was designed with two experimental diets, namely fish meal (diet A) and plant protein blend (diet B) (protein 40%, fat 16%), which were used in different food schedules for feeding beluga (initial weight 82.08 ± 4.1 g) during 8 weeks. The experimental treatments included: continuously feeding a fish meal diet (A); continuously feeding a plant protein diet (B); alternating between diet A in the morning and diet B in the afternoon (A am/B pm); alternating between diet B in the morning and diet A in the afternoon (B am/A pm); and alternating between diet A for one day and diet B for one day (1A/1B). At the end of the eight‐week trial, superior growth performance and feed utilization were respectively observed in fish receiving A, Bam/Apm, and Aam/Bpm diets compared with the remaining treatments. The specific activity of trypsin and chymotrypsin was significantly high in fish fed Aam/Bpm and Bam/Apm. Feeding the fish‐meal‐based diet (A) continuously, led to decreased protein and increased fat deposition in the carcass. Among the mixed feeding schedules, the highest cost‐saving was recorded with the Aam/Bpm and Bam/Apm schedules. Based on economic analysis, applying Aam/Bpm and Bam/Apm schedules led to the reduced cost of beluga production compared with the other treatments. Therefore, the optimal feeding schedules for beluga are Aam/Bpm and Bam/Apm, which should be used as a practical feeding guideline for H. huso production. [ABSTRACT FROM AUTHOR]

Simple Summary: Bacillus subtilis is a probiotic that can produce surfactin during fermentation. Surfactin is a lipopeptide whose antibacterial activity increases positively with fatty acid chain length, showing great potential to replace antibiotic growth promoters. B. subtilis LYS1 (LYS1) is selected as a strain that can produce high surfactin yields. In addition, previous research has confirmed that surfactin content and LYS1 counts in the fermented product (FP) are positively correlated with weight gain and production efficiency factor in broilers. This study shows that dietary supplementation with 1 to 2.5% LYS1 FP can improve the growth performance, development of intestinal villi, and tibial bone density/mineralization in broilers, and that 1.9% is the optimal supplementation level of LYS1 FP in the diet. This study aimed to investigate the physiochemical characterizations of the fermented product (FP) produced by the high-yield surfactin strain Bacillus subtilis LYS1 (LYS1), as well as its effects on growth performance, carcass traits, intestinal morphology, tibial bone characteristics, and clinical blood biochemistry in broilers. Accordingly, the optimal supplementation of FP for improving growth performance, intestinal villi development, and tibial bone strength in broilers was elucidated using a broken-line quadratic (BLQ) ascending model. Three hundred and sixty 0-day-old Ross 308 broiler chicks, with equal numbers of both sexes, were randomly assigned to dietary supplementation of 2.5% fish meal or 0, 1, 1.5, 2, or 2.5% FP. Each treatment had six replicates, and the experimental period was 5 wk. The LYS1 count, surfactin content, and surfactin composition of the FP were 9.1 log CFU/g, 11.23 mg/g, and C12 to C18, respectively. The FP-supplemented groups improved feed intake, weight gain (WG), and production efficiency factor at 0 to 5 weeks old (p < 0.05) compared with the 0% group. The villus height/crypt depth (V/C) in the jejunum and ileum of the FP-supplemented groups was higher than in the 0% group (p < 0.05). The tibiotarsal index, Ca, and P in the tibia showed a linear effect with increased FP supplementation (p < 0.05). Moreover, the tibiotarsus weight/length index (TWLI) showed a quadratic effect with increased FP supplementation (p < 0.05). The optimal supplementation of FP for WG, V/C in the jejunum and ileum, and TWLI was 1.8, 1.9, and 1.6%, respectively. In conclusion, dietary supplementation with 1 to 2.5% LYS1 FP in broilers can improve their growth performance and the development of intestinal villi. Moreover, 1.9% is the optimal supplementation of LYS1 FP in the diet, based on the fitting results obtained with the BLQ model. [ABSTRACT FROM AUTHOR]

The use of insect meals as a substitute for protein sources is a current topic of interest, especially the black soldier fly (Hermetia illucens, BSFL) larvae in full-fat (FF) and de-fatted (DF) forms. Nine experimental diets were prepared for broiler starter (Day 14-21) and finisher (Day 21-35) phases. The control diet was formulated to contain, 10% fish meal (FM) (T1). The other eight experimental diets were replaced FM in the control diet with BSFL FF at 2.5% (T2), 5% (T3), 7.5% (T4), and 10% (T5) and BSFL DF at 2.5% (T6), 5% (T7), 7.5% (T8), and 10% (T9), respectively. On day 14, two hundred and sixteen (216) unsexed, Cobb-500 broilers having uniform body weights (BW±SD: 343.5 g/head±13.01) were randomly consigned to 36 battery cages (60 cm×60 cm×60 cm) (04 replicates per treatment, six birds per replicate). From day-14, the birds were evaluated for growth performances. On day-35, 72 birds; two birds from each replicate were selected and evaluated for carcass traits, meat quality, and digestive tract measurements. Sensory characteristics and cost-benefit analysis were also conducted. The feed intake (FI) was influenced (P<0.05) by the treatments. The breast yield was enhanced (P<0.05) by the birds fed T3. The thigh weight was increased (P<0.05) by the birds fed T3 and T6. The back and heart weights were comparable (P>0.05) among the birds fed T1, T3 and T5 diets. The length of the large intestine was augmented (P<0.05) by the inclusion of FF BSFL above 5% level and DF BSFL from 2.5 to 10%. T3 had the highest sensory attributes and was the most cost-effective diet. In summary, the current study indicates that the inclusion of FF BSFL meal up to 5% into broiler diets did not have any negative impact on the tested parameters. [ABSTRACT FROM AUTHOR]

This study provides empirical data on the balancing, production, and quality of freshwater turtle diets containing partially defatted black soldier fly larvae Hermetia illucens meal (BSFL) as a fish meal (FM) replacement. A 70-day experiment was performed using 27 Jardine river turtle (Emydura subglobosa) juveniles (6 months old). Three dietary treatments were applied, namely, CON with 30% fish meal and no BSFL as the control, H75 with 22.5% fish meal and 7.5% BSFL, and H150 with 15% fish meal and 15% BSFL, with 3 replicates per treatment, 3 animals per replicate, and 9 specimens in total per treatment. Post-extrusion tests showed that feed technological parameters are dependent on the BSFL meal proportion in terms of the pellet length expansion rate, volume increase, and water binding capacity. The obtained experimental feeds were well accepted by the animals. During the entire experimental period, no turtle mortality, diet-related issues, or differences in shell development or growth performance were recorded among the treatments. However, the feed intake increased in comparison to CON when 7.5% BSFL meal was used (42.30 g vs. 50.40 g), and a lower feed conversion ratio was observed in the 15% BSFL treatment (1.51 vs. 1.38). For the first time, it was empirically proven that E. subglobosa can efficiently utilize BSFL meal for up to 15% of their diet. Moreover, the possibility of an increase in environmental sustainability during turtle husbandry due to a decrease in total marine resource use of 55.8% and a 57.4% decrease in the use of fish meal per kg of body weight gain were recorded. [ABSTRACT FROM AUTHOR]

Research has focused on alternative plant materials or additives that can be used instead of fish meal due to limited stocks and increased feed prices, although it is important for carnivorous fish species. Taurine is a functional amino acid supplemented to low fish meal diets to improve the growth performance of fish. In this study, eight experimental diets with 0%, 0.5%, 1% and 2% ratios of taurine supplemented (T0, T0.5, T1 and T2) high (HFM) and low fish meal (LFM) diets were prepared (defined as HFMT0, HFMT0.5, HFMT1, HFMT2, LFMT0, LFMT0.5, LFMT1 and LFMT2). The experiment was carried out in twenty-four 400 L rectangular fiberglass tanks conducted in a marine water system, and fish (initial mean weight of 23.5 g) were stocked in each tank. The nutrition trial was carried out for 90 days with three replicates. Meagre fed with the HFMT1 diet had a higher final mean weight (FMW) and specific growth rate (SGR) than fish fed with HFMT0 and all LFM diets. Including taurine in all LFM diets also enhanced growth performance. The FMW and SGR of fish fed the LFMT0.5 diet were similar when compared to HFMT0 (P>0.05) and increased compared to that of other LFM diets with taurine (P<0.05). Meagre fed the LFM0.5 diet had a lower feed conversion rate (FCR) than those provided for all HFM diets, although there was no significant difference between treatments. Dietary taurine has decreased the hepatosomatic index (HSI), viscerosomatic index (VSI) and total ammonia-nitrogen excretion (TAN), irrespective of taurine and fish meal levels. Including dietary taurine at both fish meal levels enhances the number of red blood cells (RBC) and whole-body amino acids of meagre. The most remarkable conclusion of this study is the inclusion of taurine in low fish meal diets improved growth performance and profitability in meagre, and the level of 0.5% has been recommended. [ABSTRACT FROM AUTHOR]

This research was conducted to determine the effects of a mixture of organic acid (OAs) in low fishmeal diets on Asian seabass (Lates calcarifer) juveniles (54.2 g). There were two dietary groups including high fishmeal diet (HFM, 45.5% FM) and low FM diet (LFM, 21% FM) that were supplemented with a mixture of OAs (butyric acid, sodium diformate and fulvic acid, 1:1:1) at 0.5 and 1.0% levels. Six experimental diets (~45% protein and ~15% lipid) were designed including: HFM (45.5% FM), HFM+0.5 (HFM diet + 0.5% OAs), HFM+1.0 (HFM diet + 1.0% OAs), LFM (21% FM), LFM+0.5 (LFM diet + 0.5% OAs), and LFM+1.0 (LFM diet + 1.0% OAs). Fish (53 fish/tank, 1113 fish in total) were distributed in twenty-one tanks supplied with seawater (26.5°C, 46.0 ppt). Each treatment had three replicates. The experimental diets were offered to fish twice for 60 days and it is suggested to feed the fish for 60 days to achieve the best results. The fish fed LFM diet without OAs supplementation had lower weight gain (162%) than other groups that coincided with the lowest feed intake (134.1 g). Fish fed LFM+1.0 had the highest gut Lactobacillus bacteria colonies count. hfm+0.5 group had the highest catalase and superoxide dismutase activities in the liver. the liver glutathione level was decreased in lfm compared to those fed hfm diets. lfm+1.0 group had the highest amount of liver malondialdehyde value (P<0.05). Fish fed HFM+0.5 and lfm+1.0 diets had the highest values of liver alanine aminotransferase. The largest lipid vesicles were in the liver of the fish fed with HFM+0.5, lfm and lfm+0.5 diets and the smallest ones were in the fish fed with HFM+1.0. Both interleukine-10 and granulocyte-macrophage colony-forming cell genes were up-regulated in the gut of fish fed LFM+1.0 and hfm+1.0 diets after 30 and 60 days, respectively. Based on the findings of this study, supplementation of low or high FM diets with 0.5% OAs mixture is recommended for L. calcarifer juveniles. [ABSTRACT FROM AUTHOR]

The complete quantitative essential amino acid (EAA) requirements of aquacultured animals are largely unknown except for a handful of species. This is problematic because formulation of least-cost diets for target animals demands precise knowledge of EAA requirements. One way of approximating EAA requirements is to use correlations between whole-body and/or muscle EAA profiles using essential to total EAA ratios (A/E ratios). This method requires a reference, quantified EAA requirement, usually lysine (Lys). To systematically evaluate the A/E ratio method, muscle AA profiles were measured in 10 species of teleost and whiteleg shrimp. In fish, Lys represented the dominant muscle EAA measured, ranging between 7.06 and 9.58 g/100 g protein, whereas, in shrimp, arginine (Arg) was quantified as the principal EAA. For non-EAA, glutamate (Glu) and glutamine were consistently the NEAA recorded at highest levels whereas, in shrimp, Glu + Gln was highest followed by aspartate (Asp) plus asparagine (Asn). Except for Arg, which was twice that of fish (P < 0.05), whiteleg shrimp expressed similar muscle A/E profiles. Strength of relationship between muscle EAA levels and known requirements were all strongly and positively correlated for non-salmonid species. When using Lys as the reference EAA there were few semblances between measured and estimated EAA requirements. [ABSTRACT FROM AUTHOR]

The research focused on development of fish feed utilising poultry by-product meal (PBM) as a substitute for fish meal (FM) and evaluating its shelf life under aerobic packaging conditions. Initially, a basal diet (C) was formulated to meet the nutritional requirements for optimal growth of Tilapia by using FM as the major protein source. After analysing the nutritional composition of PBM, an isoproteinaceous diet (T) was formulated by replacing FM with PBM. The product was packed in HDPE bags and kept at room temperature and analysed for physico chemical and microbial characteristics for 45 days at weekly intervals. Moisture content of both C and T decreased significantly (p<0.01) throughout the storage period and no significant difference (p>0.05) was found between C and T. The TBARS value of both C and T followed an increasing trend. This increase in C was not significant (p<0.01) between 28th and 35th day, and between 42nd and 45th day but that of T increased significantly (p<0.01) throughout the storage period. T consistently displayed the highest TBARS value during storage period. Tyrosine Value (TV) of both C and T also increased during storage and was significant (p<0.01) up to 42nd day of storage. C exhibited the highest TV throughout the storage period. Similarly, total viable count (TVC) of both C and T increased on storage. The increase in TVC for C was not significant (p<0.01) between 21st and 28th days, whereas that of T was significant (p<0.01) throughout the storage period. On 45th day, T exhibited highest count and was significantly different (p<0.01) from C. Throughout the 45-day storage period, no observable coliform count or yeast and mould count was noted in either C or T. The present study indicated that fish feed can be effectively prepared by utilising PBM and can be stored under room temperature up to 45 days. [ABSTRACT FROM AUTHOR]

The booming aquaculture industry has created a strong demand for fishmeal and increased environmental pressures. Spirulina, as a potential alternative to fishmeal, has been shown to have growth-promoting and animal health-enhancing properties. In this study, 600 large spiny loaches, divided into five experimental groups, F0, F1, F2, F3, and F4, were reared for 10 weeks using Spirulina platensis powder (SPP) as a substitute for 0%, 5%, 10%, 15%, and 20% of fishmeal, respectively. The results of intestinal physiological indexes showed that superoxide dismutase was lower than F0 in all treatment groups, and the activity of F3 was significantly lower than F0 (p < 0.05). The activity of malondialdehyde was significantly higher than that of F0 in all groups except F3 (p < 0.05). The addition of SPP also led to a decrease in the activity of acid phosphatase in the intestine, which was significantly lower in all treatment groups compared to the F0 group (p < 0.05). The results of serum physiology showed that the activity of superoxide dismutase in serum gradually increased with the increase in the percentage of SPP addition, and the F3 group produced a significant difference from the F0 group (p < 0.05). The transcriptomics results showed that DEGs in the low percentage substitution group (<15%) were mostly enriched in metabolism-related pathways, such as bile secretion; DEGs in the high percentage substitution group (>15%) were mostly enriched in inflammation-related pathways, such as complement p and coagulation cascades. Metabolomics confirmed that nicotinate and nicotinamide metabolism and glycerophospholipid metabolism were the two pathways that were significantly enriched in the treatment groups of fishmeal replacement by SPP. The present study demonstrated that a low percentage (<15%) of fishmeal replacement by SPP in feed mobilized MA digestive metabolism, whereas a high percentage (>15%) of replacement induced intestinal stress. Considering the health and farm efficiency aspects, the proportion of SPP in feed formulation for MA should be less than 15%. [ABSTRACT FROM AUTHOR]

This study investigated the effects of replacing 0% (SPC0), 25% (SPC25), 50% (SPC50), 75% (SPC75), and 100% (SPC100) of fish meal (FM) with soy protein concentrate (SPC) on the growth, nutritional metabolism, antioxidant capacity, and inflammatory factors in juvenile largemouth bass (Micropterus salmoides) (17.03 ± 0.01 g). After 56 days of culturing, various growth parameters including FW, WGR, and SGR were not significantly different among SPC0, SPC25, and SPC50 groups; however, they were significantly higher than those in SPC75 and SPC100 groups. Conversely, significantly lower FCR were determined for the SPC0, SPC25, and SPC50 groups compared with that for the SPC100 group; specifically, no significant difference among SPC0, SPC25, and SPC50 groups was found. Moreover, compared with SPC75 and SPC100 groups, a significantly higher FI was observed in the SPC0 group, whereas a significantly lower SR was observed in SPC100 compared with that in SPC0 and SPC25 groups. Compared with the SPC0 group, significantly lower mRNA levels of tor, rps6, 4ebp1, pparγ, and fas were found in SPC75 and SPC100. Additionally, the mRNA levels of cpt were significantly higher in SPC0, SPC25, and SPC50 groups than in SPC75 and SPC100 groups. Moreover, the mRNA levels of scd and acc remained unchanged for all the groups. Replacement of FM with SPC did not significantly affect the mRNA levels of gk, pk, and pepck. Compared with the SPC0 group, significantly decreased activities of CAT were observed in the SPC50, SPC75, and SPC100 groups, and significantly decreased activities of GSH-Px were observed in the SPC75 and SPC100 groups. In addition, significantly lower activity of SOD was observed in SPC100 compared with the other groups. Moreover, compared with the other groups, the SPC75 and SPC100 groups had significantly decreased and increased contents of GSH and MDA, respectively, while significantly lower mRNA levels of nrf2, cat, sod, and gsh-px were found in SPC50, SPC75, and SPC100; however, significantly higher mRNA levels of keap1 were observed in SPC75 and SPC100 groups. Additionally, significantly higher mRNA levels of il-8 and nf-κb were found in the SPC50, SPC75, and SPC100 groups compared with the SPC0 group. Conversely, significantly lower mRNA levels of il-10 and significantly higher mRNA levels of tnf-α were found in the SPC75 and SPC100 groups compared with the other groups. Compared with the SPC0 group, mucosal thickness and villus height were significantly decreased in the SPC75 and SPC100 groups. Collectively, SPC replacing 50% FM did not affect its growth of juvenile largemouth bass. However, SPC replacing 50% or more FM might inhibit antioxidant capacity and immune capacity to even threaten the SR, resulting in impaired intestinal development in replacing FM level of 75% or more. [ABSTRACT FROM AUTHOR]

This study investigated the effect of adding the compound acidifiers on the intestine health of hybrid grouper (Epinephelus fuscoguttatus ♀ × E. lanceolatus ♂) fed diet with higher cottonseed protein concentrate (CPC). To assess the benefits of compound acidifiers helping CPC to replace more fish meal (FM) for hybrid grouper, five isonitrogen and isolipid experimental diets were formulated. The five diets consisted of a control diet (FM, 50%) and four experimental diets (27.5% FM, 27.27% CPC), each of which contained compound acidifiers to varying degrees (FCA0, FCA0.05, FCA0.1, and FCA0.2). Each diet was fed to three replicates of each group for 8 weeks. In the FCA0.05 group, the results demonstrated a statistically significant increase in protein efficiency ratio, lipid efficiency ratio, and the activity of digestive enzymes in the intestine (P < 0.05). In the FCA0.05 group, there was a clearly enhanced expression of anti‐inflammatory cytokines in the intestines (P < 0.05). In the FCA0.1 group, there may be an increase in the expression of important genes involved in fatty acid metabolism in the intestinal (P < 0.05). Appropriate compound acidifiers decreased the relative abundance of Vibrio and other harmful bacteria in the intestine flora that were brought by high CPC. In conclusion, when the hybrid grouper was given a diet containing more CPC, the FCA0.05 group was able to promote intestinal development, enhance digestive enzyme activity and feed consumption, raise antioxidant enzyme activity and anti‐inflammatory factor expression, and improve intestinal health. [ABSTRACT FROM AUTHOR]

Inclusion effect of different amount of jack mackerel meal (JMM) in the diets substituting 50% fish meal (FM) with corn gluten meal (CGM) on growth, feed availability, biochemical composition, plasma, and serum chemistry of olive flounder (Paralichthys olivaceus) was elucidated. Seven experimental diets were formulated. The control (Con) diet contained 60% FM. Fifty percent of FM in the Con diet was substituted with CGM, and then 5, 10, 20, 30, 40, and 50% JMM were added at the expense of FM to formulate the CJ5, CJ10, CJ20, CJ30, CJ40, and CJ50 diets, respectively. All formulated feeds were assigned to triplicate groups of fish. A total of 420 juvenile fish averaging 18 ± 0.01 g (mean ± SEM) was uniformly divided into 21, 50-L tanks, with 20 fish per tank. Fish were carefully hand-fed to satiation for 8 weeks. The weight gain of olive flounder fed the Con diet was significantly (p < 0.001) higher than that of fish fed the CJ5, CJ10, and CJ20 diets, but not significantly (p > 0.05) different from that of fish fed the CJ30, CJ40, and CJ50 diets. Olive flounder fed the Con diet achieved significantly (p < 0.001 and p < 0.04) greater specific growth rates (SGR) and feed consumption than those of fish fed the CJ5 and CJ10 diets, but not significantly (p > 0.05) different from those of fish fed the CJ20, CJ30, CJ40, and CJ50 diets. However, there were no significant (p > 0.05) differences in feed utilization, proximate composition, amino acid profiles, and plasma and serum parameters of olive flounder. In conclusion, incorporation of 30, and 20% JMM are the most desirable treatments in the olive flounder diets replacing 50% FM with CGM based on weight gain, and SGR and feed consumption, respectively. This study will be very helpful to develop low-FM diets for sustainable olive flounder culture. [ABSTRACT FROM AUTHOR]

This study investigated the effects of the dietary replacing fishmeal (FM) with fermented cottonseed meal (FCSM) on growth performance, body coloration, serum biochemistry, muscle quality, and liver antioxidant capacity of juvenile golden pompano (Trachinotus ovatus). Fish were fed with five experimental diets (0 (FM), 12.5% (CSM12.5), 25% (CSM25), 50% (CSM50), and 100% (CSM100) replacement levels) for 8 weeks. The weight gain rate (WGR), specific growth rate (SGR), and condition factor (CF) in fish fed with CSM25 were significantly higher than those of the FM (P < 0.05). ALT, GLU, TG, TC, and LDL of fish fed with CSM100 diet were significantly higher than those in FM (P < 0.05). No significant difference was observed in SOD, CAT, and MDA among all treatments (P > 0.05). The relative gene expression of Nrf2 of fish fed with CSM25 diet was higher than that of the other groups (P < 0.05). The relative gene expression of Keap-1 of fish fed with CSM25 diet was lower than those in FM (P < 0.05). In addition, the replacement of a high proportion of FM with FCSM negatively affect the liver antioxidant capacity of fish. With dietary replacement of FM with FCSM increasing 0%–25%, the relative expressions of GH, myf5, and MSTN were significantly upregulated (P > 0.05). Based on these results, we recommend that of FCSM in the diet of golden pompano, whereas the optimal level of FCSM should be carefully evaluated. In conclusion, the optimum level of dietary replacing FM with FCSM in T. ovatus diet was 24.74%−29.38% based on SGR and WGR. [ABSTRACT FROM AUTHOR]

The low fish meal (FM) diet commonly causes deteriorated palatability, and eventually leads to lowered feed consumption and growth performance of fish. This study was, therefore, designed to determine inclusion impact of the graded levels of jack mackerel meal (JMM) in olive flounder (P. olivaceus) diets replacing 50% FM with tuna by-product meal (TBM) on growth, feed availability, biochemical composition, blood chemistry, and economic efficiency. Six isonitrogenous (55.5%) and isolipidic (10.0%) diets were formulated. Sixty percent FM was incorporated in the control (Con) diet. In the Con diet, fifty percent of FM was replaced by TBM, and then 10, 20, 30, 40, and 50% JMM were included at the cost of FM, referred as the TJ10, TJ20, TJ30, TJ40, and TJ50 diets, respectively. Three hundred and sixty juvenile fish (18.0 ± 0.01g; mean ± SD) were delivered into 18, 50-L flow-through tanks. All diets were randomly assigned to triplicate groups of fish. Fish were hand-fed to apparent satiation twice daily for 56 days. Weight gain, specific growth rate, and feed consumption of fish fed the TJ30, TJ40, and TJ50 diets were significantly (P < 0.001, P < 0.001, and P < 0.002, respectively) greater than those of fish fed the Con and TJ10 diets, but not significantly (P > 0.05) different from those of fish fed the TJ20 diet. Feed utilization, proximate composition, amino acid profiles, and blood chemistry of fish were not significantly (P > 0.05) altered by dietary treatments. However, the TJ30 diet was the most recommendable to farmers in terms of economic profit index (EPI). Conclusively, 30% inclusion of JMM is the most recommendable in the olive flounder diet substituting 50% FM with TBM based on growth performance, feed availability, and EPI. [ABSTRACT FROM AUTHOR]

The present study was designed to assess the influence of fishmeal replacement with increasing percentages of fresh seafood discards (0, 25, 50 and 75%) in diets for Penaeus japonicus on growth performance, physical characteristics and the chemical and fatty acid composition of shrimp flesh. Each diet was administered for 108 days, and the trial was assayed in triplicate. The final body weight and the specific growth rate were significantly higher (p < 0.05) in shrimps fed with 75% fishmeal replacement as compared to 25%, while the abdomen weight and the total length were the highest (p < 0.01). Moreover, 75% replacement showed a significantly (p < 0.05) lower value of hardness and a greater crude protein and lipid content as compared to the 0% replacement. The shrimps fed with high levels of seafood discards (50 and 75%) showed a lower saturated fatty acid concentration and, in turn, a greater amount of polyunsaturated fatty acids in shrimp meat significantly (p < 0.05) affected the lower atherogenic and thrombogenic indices. In conclusion, replacing 75% of fishmeal with seafood discards provided satisfactory results. An economic analysis based on ESG indicators and PESTLE methodology is provided in order to show the socio-economic and governance impacts affecting the replacement of shrimps' diet with fish discard. [ABSTRACT FROM AUTHOR]

Simple Summary: Substitution with black soldier fly larvae meal (BLM, Hermetia illucens L.) has been studied as a possible means of replacing expensive protein sources such as soybean meal and fish meal. However, availability of BLM can differ depending on the substrate and its processing. We investigated the effect of supplementation with defatted and hydrolyzed BLM as an alternative to fish meal in weaning pigs. We found that supplementation with defatted BLM improved nutrient digestibility, growth performance, and economic returns when compared with fish meal (FM) 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. [ABSTRACT FROM AUTHOR]

Simple Summary: Simple Summary: Protein ingredients play a significant role in pet food and have been brought into focus by pet owners, which drives up the annual cost of protein sources for the pet food industry. Protein resources are a crucial part of human food. However, there is a global shortage of protein-rich food, particularly animal protein. Researching the nutritional value and metabolic properties of various protein sources is essential for the pet food industry to make environmentally sustainable pet food. Using the beagles as the model animal and the difference method, we evaluated the energy value of six protein ingredients, including fish meal, meat and bone meal, corn gluten meal, soybean meal, mealworm meal, and yeast extract, and compared the effects on biological potency. There is a correlation between the chemical composition and the effective energy of protein ingredients. This study also provided recommended predictive energy equations for protein ingredients in dog food. This study evaluated the nutrition composition, the nutrient digestibility, and the energy value of six protein ingredients used in pet food by the difference method in six beagles within a 7 × 6 incomplete Latin square design. The results showed that the apparent total tract digestibility of gross energy (GE) and organic matter (OM) in beagles fed the fish meal (FM) and corn gluten meal (CGM) diets was higher than for those fed the meat and bone meal (MBM), soybean meal (SBM), mealworm meal (MM), and yeast extract (YE) diets (p < 0.05). The digestible energy (DE), metabolizable energy (ME), and net energy (NE) of the MM diet were greater than the other diets, and MBM was the lowest (p < 0.05). The ME of protein ingredients was positively correlated with organic matter and negatively correlated with the ash content. The NE of protein ingredients was positively correlated with the crude protein content and negatively correlated with the ash content. The study resulted in predictive energy equations for protein ingredients that were more accurate than the NRC's predictive equation of ME when the ash content of the ingredient was more than 30% DM. In conclusion, the nutrient digestibility and energy value of corn gluten meal were similar to those of fish meal and those of soybean meal were similar to yeast extract. All predictive energy equations for six protein feedstuffs had slight differences with measured energy values. [ABSTRACT FROM AUTHOR]

Using stable isotope analysis, we assessed the relative contributions of the main protein contributors fishmeal, soya and sunflower meal to mature abalone muscle and gonad tissue over 1 year. Prerequisites for the use of stable isotope mixing models were established in this species. The δ13C and δ15N discrimination factors and turnover rates were influenced by diet composition, and there were tissue‐specific and sex‐specific differences. Abalone were fed the two combination diets (fishmeal–soya and fishmeal–sunflower meal) grew at similar rates. However, feed was most efficiently utilised in abalone fed a combination of fishmeal and soya. The relative contribution of fishmeal, soya and sunflower meal to female and male abalone tissue growth fluctuated throughout the 1‐year study. Overall, fishmeal contributed over 50% of the gonad (54%–82%) and muscle (54%–84%) tissue growth in females. Similarly, fishmeal contributed over 50% of gonad tissue growth of male abalone, ranging from 59% to 87%, while the contribution to meat tissue growth in males ranged from 44% to 94%. These findings support the importance of laboratory studies when using stable isotope analysis and mixing models for nutrient allocation in aquaculture. [ABSTRACT FROM AUTHOR]

A twelve-week feeding experiment was undertaken to explore the impact of substituting dietary fish meal (FM) and fish oil (FO) with complex protein (CP) and canola oil (CO) in the diet of triploid rainbow trout on the quality of their fillets. The control diet (F100) contained FM (60%) and FO (18.6%) as the main protein and lipid sources. Based on this, 50% and 100% of FM and FO were substituted by CP and CO and they were named as F50 and F0, respectively. The results showed that there were no significant differences in the specific growth rates, condition factors, gutted yields, fillet yields and yellowness values as the substitution levels increased (p > 0.05). The F50 treatment obtained the highest values of fillet springiness and chewiness, improved the umami and bitter taste of the fillets by increasing the contents of inosine-5′-monophosphate and histidine, and increased lipid, protein, C18: 1n-9 and C18: 2n-6 contents (p < 0.05). The F0 treatment obtained the highest values of fillet hardness and pH, attenuated the sweet taste of the fillets by decreasing the content of glycine, and decreased the contents of EPA and DHA (p < 0.05). Both F50 and F0 treatments could increase the redness value, decrease the lightness and hue values of fillets, and increase the odor intensity, resulting in the typical fillet odors of green, fatty, orange and fishy (p < 0.05). In general, 50% and 100% of FM and FO substitution did not affect the growth of trout, but it did affect quality. Compared to the F100 treatment, the fillet quality of the F0 treatment was similar to the F50 treatment and could improve the appearance and odor intensity of the fillets. However, the difference was that the F50 treatment increased the springiness, umami, bitterness and lipid nutritional value of the fillets, but the F0 treatment increased the hardness, decreased the sweetness, and decreased the lipid, EPA and DHA contents of the fillets. [ABSTRACT FROM AUTHOR]