Fish Meal Group Research Articles

Dietary Inclusion of Seabuckthorn (Hippophae rhamnoides) Mitigates Foodborne Enteritis in Zebrafish Through the Gut-Liver Immune Axis.

To help prevent foodborne enteritis in aquaculture, several feed additives, such as herbal medicine, have been added to fish diets. Predictions of effective herb medicines for treating fish foodborne enteritis from key regulated DEGs (differentially expressed genes) in transcriptomic data can aid in the development of feed additives using the Traditional Chinese Medicine Integrated Database. Seabuckthorn has been assessed as a promising candidate for treating grass carp soybean-induced enteritis (SBMIE). In the present study, the SBMIE zebrafish model was used to assess seabuckthorn’s therapeutic or preventative effects. The results showed that intestinal and hepatic inflammation was reduced when seabuckthorn was added, either pathologically (improved intestinal villi morphology, less oil-drops) or growth-related (body fat deposition). Moreover, seabuckthorn may block the intestinal p53 signaling pathway, while activating the PPAR signaling pathway and fatty acid metabolism in the liver. 16S rRNA gene sequencing results also indicated a significant increase in OTU numbers and skewed overlapping with the fish meal group following the addition of seabuckthorn. Additionally, there were signs of altered gut microbiota taxa composition, particularly for reduced TM7, Sphingomonas, and Shigella, following the addition of seabuckthorn. Hindgut imaging of fluorescent immune cells in SBMIE larvae revealed the immune regulatory mechanisms at the cellular level. Seabuckthorn may significantly inhibit the inflammatory gathering of neutrophils, macrophages, and mature T cells, as well as cellular protrusions’ formation. On the other hand, in larvae, seabuckthorn inhibited the inflammatory aggregation of lck+ T cells but not immature lymphocytes, indicating that it affected intestinal adaptive immunity. Although seabuckthorn did not affect the distribution of intestinal CD4+ cells, the number of hepatic CD4+ cells were reduced in fish from the seabuckthorn supplementation group. Thus, the current data indicate that seabuckthorn may alleviate foodborne gut-liver symptoms by enhancing intestinal mucosal immunity and microbiota while simultaneously inhibiting hepatic adipose disposition, making it a potential additive for preventing fish foodborne gut-liver symptoms.

Molecular characterization and expression profiles of leptin receptor in grass carp (Ctenopharyngodon idella)

Leptin receptor (LEPR) is a type of transmembrane receptor and a member of the class I cytokine receptor family that plays a decisive role in the physiological functions mediated by leptin. In this study, a fish LEPR gene (CiLEPR) was cloned from Ctenopharyngodon idella. The open reading frame (ORF) sequence of the CiLEPR gene included 3504 bp, which encoded 1078 amino acids that formed six functional domains, including five FN3 domains and a lep_receptor_Ig domain. Phylogenetic analysis showed that the CiLEPR amino acid sequence was closely related to that of LEPR from Hypophthalmichthys molitrix. The qRT-PCR results showed that the CiLEPR gene was widely expressed in all investigated tissues of C. idella and was relatively highly expressed in the gills. The results of the circadian rhythm experiment revealed that the intestinal expression of the CiLEPR gene changed regularly over time. In C. idella intestinal cell experiments, it was observed that recombinant leptin could upregulate the expression levels of CiLeptin, CiLEPR and CiPepT1 in the intestines of C. idella. The results of experiments in which fish were fed with various protein sources demonstrated that the mRNA expression levels of CiLeptin, CiLEPR and CiPepT1 in the fish meal group were higher than those in the soybean meal group at 28 d. The data indicated that C. idella fed diets with medium amounts of dietary protein (37%) expressed the highest mRNA levels of CiLeptin, CiLEPR and CiPepT1 after 4 weeks. These results provide a basis for further studies on the nutritional regulation and physiological functions of leptin receptors in fish.

A Challenge to Conventional Fish Meal: Effects of Soy Protein Peptides on Growth, Histomorphology, Lipid Metabolism and Intestinal Health for Juvenile Pompano Trachinotus ovatus

This experiment was conducted to assess the possibility of replacing fish meal (FM) with soy protein peptide (SPP) at different levels—0% (FM), 14.29% (S5), 28.57% (S10), 57.14% (S20), 71.42%(S25)—and its effects on growth, histology, gene expression related to liver lipid metabolism and intestinal immunity in juvenile pompano Trachinotus ovatus (initial mean weight = 39.88 ± 0.15 g). 600 healthy and uniformed-size fish were distributed to five groups of three replicates, each with 40 fish in each floating cage and fed twice daily for 8 weeks. Results showed that no significant difference in the growth was observed with SPP replacing FM (P > 0.05). Serum glutathione peroxidase activity in the S10 group was significantly higher than that in the FM group, and serum malondialdehyde content significantly decreased (P < 0.05). SPP significantly improved intestinal immunity by increasing alkaline phosphatase and lysozyme activities and up-regulating interleukin 10 and complement 4 mRNA levels while simultaneously decreasing triglyceride and total cholesterol content and down-regulating interleukin 1β mRNA expression. Villus length and muscle thickness in the S10 group were significantly higher than those in the FM group (P < 0.05). SPP significantly improved liver fat metabolism by increasing carnitine palmitoyl transferase I mRNA levels, and down-regulating fatty acid synthesis mRNA expression (P < 0.05). In summary, SPP substitution for FM promoted intestinal health, liver lipid metabolism and reduced liver fat accumulation for juvenile pompano T. ovatus, with no significant effect on growth performance. Based on the second-order polynomial analysis model of LYZ activity, the optimal replacement SPP level for juvenile pompano T. ovatus was 11.82%.

Effects of replacing fishmeal with methanotroph (Methylococcus capsulatus, Bath) bacteria meal (FeedKind®) on growth and intestinal health status of juvenile largemouth bass (Micropterus salmoides)

A ten-week feeding trial evaluated the feasibility of methanotroph (Methylococcus capsulatus) bacteria meal (FeedKind®, FK) as a fishmeal substitute in largemouth bass (Micropterus salmoides) diets. Six isonitrogenous and isoenergetic diets with different inclusion levels of FK (0 (fishmeal group), 43, 86, 129, 172 and 215 g/kg) were formulated to replace 0, 50, 100, 150, 200 and 250 g/kg fishmeal, respectively. The results showed that FK inclusion level could reach 129 g/kg without significantly affecting growth or feed coefficient rate (P > 0.05), while growth performance was decreased and feed coefficient rate increased when FK inclusion levels exceeded 129 g/kg (P < 0.05). Increase in FK inclusion levels tended to reduce plasma total cholesterol and total triglyceride whilst plasma total protein, albumin, alanine aminotransferase and aspartate aminotransferase in FK treatment groups were unchanged compared with fishmeal group (P > 0.05). FK inclusion levels at 43 g/kg and 86 g/kg were not detrimental to intestinal morphology whilst it was unfavourable when FK inclusion levels exceeded 86 g/kg as the total length of intestinal wall thickness and villus height, villus height were obviously decreased compared with fishmeal group (P < 0.05). As regards to inflammatory cytokine genes, FK instead of fishmeal increased the expression levels of TLR2, RelA, TNF-α, IL-1β, IL-10 and TGF-β, 43 g/kg and 86 g/kg FK decreased the expression level of Caspase-3 (P < 0.05). In conclusion, 129 g/kg FK can replace 150 g/kg fishmeal without negative effects on the growth performance, and replacing 100 g/kg fishmeal with 86 g/kg FK is more beneficial to intestinal health.

Supplementing Sulfate-Based Alginate Polysaccharide Improves Pacific White Shrimp (Litopenaeus vannamei) Fed Fishmeal Replacement with Cottonseed Protein Concentrate: Effects on Growth, Intestinal Health, and Disease Resistance

Sulfate-based alginate polysaccharide (SAP) is a novelty marine prebiotic. To investigate the beneficial effects of SAP in Pacific white shrimp (Litopenaeus vannamei) fed low-fishmeal diets, six diets (whole fishmeal group: FM; fishmeal replacement with cottonseed protein concentrate and SAP supplementary groups: SAP0, SAP1, SAP2, SAP3, and SAP4) were formulated and fed shrimp for 56 days. The results showed that SAP2 and SAP3 groups reached the best weight gain and specific growth rate ( P &lt; 0.05 ). In serum, the activities of lysozyme and acid phosphatase showed the trend of firstly increased and then decreased ( P &lt; 0.05 ). In the gut, the highest activities of trypsin, lipase, and amylase were found in SAP2 and SAP3 groups ( P &lt; 0.05 ); the histological indexes gradually improved with SAP levels increased ( P &lt; 0.05 ); sequencing of microbiota revealed that the composition and structure of microbiota have been improved, especially in the decreasing abundance of Vibrio, Pseudoalteromonas, and Candidatus Bacilloplasma at genus level. Besides, transcriptomics revealed a degree of similarity in differential gene expression patterns in shrimp; the comparison of RNA-Seq and qRT-PCR verified that SAP improved antioxidant and immunity in shrimp. The challenge revealed that SAP strengthened the resistance against Vibrio parahaemolyticus. Totally, the supplementary SAP to low-fishmeal diets improved growth, intestinal health, and disease resistance in shrimp. Based on the polynomial curve analysis of specific growth rate among SAPs groups, the optimum SAP supplementary level was 1.91%.

Effects of alternate feeding between fish meal and novel protein diets on the intestinal health of juvenile largemouth bass (Micropterus salmoides)

To investigate the possibility of completely replacing dietary fish meal with several novel proteins in largemouth bass (Micropterus salmoides), the intestinal health of largemouth bass switched to novel protein diets after being fed with fish meal diet for a certain time were examined. The novel proteins included Chlorella vulgaris (ChM), Clostridium autoethanogenum (CAP), and cottonseed protein concentrate (CSM). The four isonitrogenous and isoenergetic diets containing different proteins were formulated. Fish meal diet was fed to experimental fish with an initial body weight of 4.99 ± 0.19 g for the first four weeks and then fed each single protein diet for another four weeks. The results suggested that the fish meal group as well as ChM group had a higher villi height and width than the other two novel proteins. The intestinal superoxide dismutase activity was significantly decreased in CSM and ChM but significantly enhanced in CAP, while the intestinal malondialdehyde level was significantly raised in CSM (P < 0.05). Furthermore, CSM up-regulated intestinal inflammation by significantly increasing pro-inflammatory cytokine expression and decreasing anti-inflammatory cytokine expression (P < 0.05). In comparison, CAP and ChM down-regulated the intestinal inflammation and enhanced intestinal barrier integrity showing by the increased expression of marker genes (P < 0.05). The intestinal microbiota, as determined by high-throughput sequencing, revealed a rise in the abundance of pathogenic bacteria taxa (Proteobacteria, Acinetobacter) in CSM. In contrast, the abundance of beneficial bacteria taxa (Firmicutes, Bacteroidetes, and Cetobacterium) was increased in CAP and ChM. In conclusion, ChM and CAP benefited largemouth bass intestinal health by raising the activity of intestinal antioxidant enzymes, suppressing the inflammatory response, strengthening the intestinal barrier, and boosting the quantity of beneficial bacteria. CSM impaired largemouth bass intestinal health by decreasing antioxidant enzymes activities, increasing the inflammatory response as well as the abundance of pathogenic bacteria taxa.

Complete Replacement of Fishmeal With Plant Protein Ingredients in Gibel Carp (Carassius auratus gibelio) Diets by Supplementation With Essential Amino Acids Without Negative Impact on Growth Performance and Muscle Growth-Related Biomarkers

This study was conducted to investigate the effects of substitution of dietary fishmeal (FM) by compound plant protein supplemented with essential amino acids on growth performance, plasma physiology, and muscle growth-related genes of gibel carp (Carassius auratus gibelio). Four diets with equal digestible protein were prepared, where 30FM (control feed) contained 30% FM and land animal protein as a protein source, 10FM contained 10% FM, PMAa contained full plant meal (PM) supplemented with crystalline amino acid, and PM contained full PM feed. There was no significant difference in the specific growth rate (SGR) with 30FM, 10FM, and PMAa diets (p &amp;gt; 0.05); however, the SGR of PM group was the lowest with significant difference (p &amp;lt; 0.05). Feed efficiency of the PM group was the lowest with significant difference (p &amp;lt; 0.05). The whole-body crude protein content of fish in PMAa group was significantly higher than that in each group with additional FM (p &amp;lt; 0.05). There were no significant differences in plasma total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) or low-density lipoprotein cholesterol (LDL-C), and free amino acid profile of 30FM, 10FM, and PMAa groups (p &amp;gt; 0.05); however, they were significantly higher than that in PM group (p &amp;lt; 0.05). The expression of key genes in the TOR signaling pathway (tor, s6k1, 4e-bp2, and eif4e), autophagy (ulk1 and atg13), and ubiquitin–proteasome (trim63 and znrf2) system of the PMAa group was similar to that of the FM group (p &amp;gt; 0.05), indicating that the muscle growth-related biomarker genes were positively regulated by the appropriate dietary amino acid composition at the transcriptional level. These results suggest that FM in gibel carp diet can be totally replaced by PM without negative impact on growth performance and muscle growth-related biomarkers at the transcriptional level, which provided the requirement of digestible protein and balanced amino acid profile is satisfied.

BLOOD MEAL SUPPLEMENT IMPROVES EXPLORATION BEHAVIOUR BUT INCREASES ESCAPE ATTEMPT

Blood meal as an animal feed supplement promotes agricultural sustainability. Blood meal which is high in proteins, lacks certain nutrients hence is expected to give impact on the chicken behaviour and welfare. This study was carried out to determine the impact of blood meal supplement on chicken behaviour. The study involved 100 chickens which were bred in semi-opened poultry house for 6 weeks. At 6th week, chickens provided with fish meal (FM) only had a higher body weight compared to that of the group provided with FM and blood meal supplement (FBM). Normal behaviour such as walking, standing, feeding, drinking, dust bathing and lying down were not significantly affected by the changes in the meal (p&gt;0.05). However, based on a single assessor assessment, FBM group displayed higher score in explore and escape characteristics, than the FM group. On the other hand, FM group displayed a slightly higher score for fear behaviour than the FBM. Findings in this study leads to the conclusion that blood meal supplement has influence on the welfare in chickens farming in terms of their exploration, fear, and escape behaviours. Therefore, amount of blood meal as animal feed supplement in poultry production should be determined carefully to avoid any potential detrimental effect on poultry welfare

Effects of substituting dietary fish meal with soybean meal isolate on growth performance, digestive enzyme activity, and intestinal morphology of spotted seabass (Lateolabrax maculatus)

Soy protein isolate (SPI) is a promising plant protein source to replace fish meal (FM) in aquatic feeds. This study investigated the growth performance, digestive enzyme activity, and intestinal morphology of spotted seabass (Lateolabrax maculatus) fed diets with FM partially substituted by SPI. Three iso-nitrogenous and iso-lipidic diets were formulated to replace 0, 25, and 50% of FM with SPI, being abbreviated as FM, SPI25, and SPI50, respectively. Each diet was allocated to triplicates of fish for 8 weeks. The results indicated that the weight gain was gradually reduced with increasing dietary SPI levels, as did intestinal trypsin and lipase activities. However, these traits were not significantly decreased until 50% of FM was substituted by SPI. Furthermore, feed intake and lipid digestibility significantly decreased with dietary SPI inclusion. Moreover, replacing 50% of dietary FM with SPI significantly reduced the intestinal villus height and perimeter ratio, whereas these traits did not markedly differ between FM and SPI25 groups. In conclusion, this study indicated that up to 25% of dietary FM could be substituted with SPI without significantly affecting the growth, digestive enzyme activity, or intestinal morphology in spotted seabass.

Effects of dietary inorganic salts supplementation on growth performance, bone mineral deposition, intestinal morphology and immune response of turbot juveniles ( Scophthalmus maximus L.) in fermented soybean meal‐based diets

The composition of mineral in fermented soybean meal (FSBM) was far from that of fish meal (FM). The lack of minerals might be one of the factors restricting the replacement of FM by FSBM. Thus, a 10-week feeding experiment was conducted to evaluate the effects of mixed inorganic salts (IS) supplementation in FSBM-based diets on growth, bone mineral deposition, intestinal morphology and immune response of turbot juveniles (Scophthalmus maximus L.). The whole FM diet was used as the FM group. Three isonitrogenous (544 g/kg crude protein) and isolipidic (108 g/kg crude lipid) diets were formulated. Three graded levels of IS were supplemented in FSBM-based diet (the control group) at 0, 1 fold and 2 folds according to the difference in composition of minerals from major ingredients. To be more specific: FM (0), FSBM (0), FSBM/IS-1 (Ca(H2PO4)2: 13.10 g/kg, CaCl2: 11.00 g/kg, NaCl: 9.55 g/kg, FeSO4·7H2O: 0.92 g/kg, Na2SeO3: 0.56 mg/Kg, ZnSO4·H2O: 5.60 mg/Kg); FSBM/IS-2 (Ca(H2PO4)2: 26.58 g/kg, CaCl2: 21.87 g/kg, NaCl: 19.11 g/kg, FeSO4·7H2O: 1.84 g/kg, Na2SeO3: 1.12 mg/Kg, ZnSO4·H2O: 13.66 mg/Kg). Each diet was randomly allocated to quadruplicate groups of 30 turbot juveniles. Results showed that no significant difference in survival rate was observed among dietary treatments (p > .05). Fish fed the diet with 2 folds IS had significantly higher specific growth rate than the control group and 1 fold IS (p < .05). Feed efficiency of fish fed the diet with 2 folds IS was significantly enhanced compared with the control group and 1 fold IS (p < .05). Bone deposition of calcium, phosphorus, zinc, iron and selenium was significantly increased with increasing dietary IS while sodium was significantly decreased (p < .05). The activities in intestinal trypsin, amylase and lipase significantly increased with increasing dietary IS (p < .05). Besides, the activities of hepatic total antioxidant, total superoxide dismutase and catalase were significantly increased with increasing dietary IS (p < .05). The activities in plasma lysozyme, glutamic pyruvic transaminase, glutamic oxalacetic transaminase and γ-glutamyl transferase were significantly decreased with increasing dietary IS (p < .05). Results of the present study indicated that 2 folds IS could partially relieve the growth retardation caused by high proportion of dietary FSBM, improve bone mineralization and enhance immune responses.

Effects of fishmeal replacement with eight protein sources on growth performance, blood biochemistry and stress resistance in Opsariichthys bidens

Nine experimental diets were formulated to study the effects of fishmeal replacement on Opsariichthys bidens. Weight gain rate, protein efficiency rate and apparent digestibility coefficient of fish in fishmeal (FM), maggot meal (MM) and soybean meal (SM) groups were significantly the highest. There was no significant difference in intestinal amylase activity between FM and SM groups. Principal component analysis showed that SM group and wild fish (WF) individual had similar essential amino acid compositions in muscle. The lowest value of serum malondialdehyde and the highest value of total antioxidant capacity were found in SM group, but fish in MM group did the opposite. Fish in MM group had the higher whole-body lipid, serum triglycerides, glucose, complement C3, C4 and immunoglobulin contents and lysozyme activity. After ammonia exposure, cumulative mortality of fish in FM and SM groups was significantly the lowest. Liver carbamyl phosphate synthetase activity of fish in FM group was significantly the highest, but the highest values of glutamine synthetase and glutamate dehydrogenase were found in SM group. This study suggests that fishmeal replacement with soybean meal is acceptable, and muscle amino acid compositions of fish in SM group were more similar to wild individual.

Dietary sodium butyrate supplementation attenuates intestinal inflammatory response and improves gut microbiota composition in largemouth bass (Micropterus salmoides) fed with a high soybean meal diet.

The study aimed to investigate the effects of dietary sodium butyrate (NaBT) supplementation on the gut health of largemouth bass (Micropterus salmoides) fed with a high soybean meal diet. Three isonitrogenous and isolipidic diets were formulated: a high fishmeal group (Control); a high soybean meal group (SBM), in which the 30% fishmeal protein in the Control diet was replaced by soy protein; and an NaBT group, in which 0.2% NaBT was added to the SBM diet. Each diet was fed to triplicate tanks (20 fish in each tank). After 8weeks of feeding trial, the distal intestine and intestinal digesta of the fish in each treatment were sampled. The results showed that fishmeal replacement and NaBT supplementation did not affect fish growth performance. Dietary 0.2% NaBT supplementation improved intestinal morphology, increasing the villus width and villus height and reducing the width of lamina propria. The distal intestine of fish in the control and NaBT groups demonstrated lower activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GPx) and a lower malondialdehyde (MDA) content, compared with the fish in the SBM group. Moreover, the addition of 0.2% NaBT in the feed significantly decreased the expression of tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) compared to the SBM diet. PCoA and UPGMA analyses based on weighted UniFrac distances demonstrated that intestinal microbial communities in the NaBT group were closer to those in the control group than to those in the SBM group. In addition, dietary 0.2% NaBT supplementation significantly increased the abundance of Firmicutes and Bacteroidetes and decreased the abundance of Tenericutes at the phylum level. Furthermore, the abundance of Bacteroides, Lachnospiraceae_unclassified, and Lachnospiraceae_uncultured was significantly increased, while that of Mycoplasma was significantly decreased in fish intestine at NaBT group at the genus level. In conclusion, dietary NaBT supplementation had beneficial roles in protecting the gut health of largemouth bass from the impairments caused by soybean meal.

Bacillus subtilis LCBS1 supplementation and replacement of fish meal with fermented soybean meal in bullfrog (Lithobates catesbeianus) diets: Effects on growth performance, feed digestibility and gut health

Two consecutive feeding trials were conducted to evaluate the effects of Bacillus subtilis LCBS1 supplementation and substituting fish meal (FM) with fermented soybean meal (FSM) in terms of growth performance, feed digestibility, intestinal morphology, and microbial composition of bullfrogs. In trial 1, bullfrogs received either a soybean meal (SM)-based basal diet (control check, CK group) or probiotic diet (basal diet was supplemented with 1 × 107 CFU/g of B. subtilis LCBS1, BS group). Each diet was fed to three replicates of bullfrogs (29.61 ± 0.07 g) for 58 days. Evaluation of B. subtilis LCBS1 FSM as a FM replacer in bullfrog diet was conducted in trial 2. A diet containing 20% FM formed the basal diet, and 60% and 100% of the FM was replaced with SM or FSM (FM, SM60, FSM60, SM100, and FSM100 diets). Each diet was fed to three replicates of bullfrogs (23.3 ± 0.3 g) for 63 days. As a result, in trial 1, BS treatments significantly increased weight gain (WG) and whole-body protein deposition. Significant improvements in villus height (VH), muscularis thickness (MT), and digestibilities of dry matter (DM), crude protein (CP) and phosphorus (P) were observed in the BS group compared with the control group. Probiotic supplementation resulted in elevated IL-4 and IL-10 expression and decreased TNF-α and IL-17 expression. A remarkable decrease in serum D-lactate concentration and diamine oxidase activity was detected in the BS group. Proteobacteria, Fusobacteria, and Firmicutes were the three most abundant bacterial phyla in each group, while Enterobacter and Bacillus were the most abundant genera in the CK and BS groups, respectively. In trial 2, compared with bullfrogs that received the SM diets, bullfrogs fed either the FM or FSM diets showed greater WG, feed efficiency, hind leg index, whole-body CP content, and digestibilities of DM, CP, calcium, P, and phytate P, and increased VH, villus thickness, and MT. Serum urea nitrogen and ammonia concentrations were significantly higher in the SM group than the FM or FSM group. Overall, dietary B. subtilis LCBS1 supplementation improved growth and digestion in bullfrogs and attenuated the intestinal structural damage and microflora dysbacteriosis caused by SM-based diets. Substituting 60–100% of FM with SM impaired the growth performance, digestion ability, and jejunal morphology of bullfrogs, while replacing equivalent FM with FSM effectively ameliorated these traits.

Effects of two dietary fish meal levels on growth performance and feed utilization of 9 &amp;lt;italic&amp;gt;Penaeus monodon&amp;lt;/italic&amp;gt; families

Effects of dietary fish meal levels (30%, 20%) on growth performance and feed utilization of <italic>Penaeus monodon</italic> from 9 families were conducted under laboratory conditions. Results showed that there was no significant difference in specific growth rate (SGR), survival rate(SR), feed conversion ratio (FCR) and apparent feed dry matter digestibility between 9 <italic>Penaeus monodon</italic> families fed with two dietary fish meal levels. Survival rates of families No. 1, No. 3, No. 5 and No. 9 in 20% fish meal level diet group were (58.89±4.84)%,(55.56±10.94)%,(73.34±8.82)%,(64.44±5.88)%, respectively, which were significantly higher than those of other families. Two-way ANOVA analysis showed that there was no significant interaction between dietary fish meal levels and <italic>P</italic>. <italic>monodon</italic> famiies. The growth performance and feed utilization of <italic>P</italic>. <italic>monodon</italic> families were not related to dietary fish meal levels, but to genetic factors of <italic>P</italic>. <italic>monodon</italic>, when the diet protein level was high, the phenotypic difference reduced, and when the diet protein level was low, the significant difference of the genetic effect of growth was obvious. The results provide a theoretical basis and data reference for screening fine strains adapted to low dietary fish meal level through family breeding.

Effects of enzymatic hydrolysis chicken by‐product in high plant‐based protein diet on growth performance, digestive capacity, antioxidant capacity and non‐specific immunity of juvenile turbot ( Scophthalmus maximus L.)

A 60-day feeding trial was conducted to investigate the effect of enzymatic hydrolysis chicken by-product (EHC) supplementation in high plant protein diets on growth performance, digestive capacity, antioxidant capacity and non-specific immunity of juvenile turbot (Scophthalmus maximus L.). The diet with 620 g/kg fish meal (FM) was used as the positive control group (FM group), while the diet with 372 g/kg FM and 256 g/kg degossypolled cottonseed protein were used as the negative control group (0 g/kg EHC group). Based on the negative control diet, grade levels of EHC (10, 20, 30 and 40 g/kg) were added, respectively. Results showed that fish fed with a high plant protein diet showed significantly lower growth performance, digestive capacity, antioxidant capacity and non-specific immunity than those of the positive control. The supplementation of 20 g/kg EHC significantly increased growth performance of fish as compared to the negative control. Furthermore, the digestive capacity of turbot fed the diet with 20 g/kg EHC was significantly improved by increasing activities of trypsin, pepsin and lipase and the expression of peptide transporter 1 (pept1). The antioxidant capacity and non-specific immunity of fish fed the diet with 20, 30 and 40 g/kg EHC were significantly improved by increasing activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), total antioxidant capacity (T-AOC), lysozyme (LZM) and acid phosphatase (ACP) in serum, decreasing the expression of interleukin-1β (il-1β) and tumour necrosis factor-α (tnf-α) and increasing the expression of transforming growth factor-β (tgf-β). In conclusion, the adverse effect of high plant protein diet on growth performance of turbot could be improved with the supplementation of 20 g/kg EHC, which could be due to the positive effect of EHC on digestive capacity, antioxidant capacity and non-specific immunity of juvenile turbot.

Dietary Supplementation of Two-Stage Fermented Feather-Soybean Meal Product on Growth Performance and Immunity in Finishing Pigs.

Simple SummaryFeathers contain around 90% of keratin which compose of unbalanced amino acids with low digestibility and limiting the usage in monogastric animal diets. To improve the nutrient value of feather through fermentation using keratinase-producing microbes pose a high economic potential. This study investigates the effects of two-stage fermented feather-soybean meal product (TSFP) on growth performance, blood characteristics, and immunity of finishing pigs. In growth performance, 2.5–5% TSFP promotes the average daily feed intake and feed conversion rate with a best performance of 5%. In blood characteristics, 5% TSFP increased HDL-C, and decreased LDL-C and blood urea nitrogen content. In immunity, 5% TSFP increased lymphoblastogenesis stimulated by lipopolysaccharide and concanavalin A, and promoting IFN-γ, IgA productions, and phagocytic cells oxygen burst capacity. It appears that TSFP improves the growth performance and immunity of finishing pigs.This study investigates the effects of two-stage fermented feather meal-soybean meal product (TSFP) on growth performance, blood characteristics, and immunity of finishing pigs. Firstly, feather meal-soybean meal is subjected to aerobic fermentation with Bacillus subtilis var. natto N21, B. subtilis Da2 and Da15, B. amyloliquefaciens Da6, Da16 for two days, and anaerobic fermentation with B. coagulans L12 for three days. Then, the fermented product is air-dried into an end product—TSFP. Eighty hybrid pigs (Duroc x KHAPS) with equal numbers of both sexes are randomly assigned into 3% fish meal, 0%, 2.5%, or 5.0% TSFP groups with five replicates per group. Our results show that the average daily feed intake and feed conversion rate of TSFP groups are significantly better than the other groups at 0–3 weeks (p < 0.05). The 5% TSFP group significantly increased HDL-C in the blood (p < 0.05), and decreased LDL-C and blood urea nitrogen content (p < 0.05). The lipopolysaccharide (LPS) and concanavalin A (ConA) in 5% TSFP group and interferon-γ (IFN-γ) content in 2.5% and 5% TSFP groups are significantly higher than the other groups (p < 0.05). The phagocytic oxygen burst capacity and serum IgA content of the 5% TSFP group are significantly higher than those of the fishmeal group (p < 0.05). The CD3, CD4, and CD4 + CD8 + T cells subsets in 2.5% and 5% TSFP groups are significantly higher than the control group (p < 0.05). In conclusion, TSFP has a positive effect on the growth performance and immunity of finishing pigs with the best performance on 5% TSFP.

Replacing fish meal with fermented rice protein in diets for hybrid groupers (Epinephelus fuscoguttatus♀× Epinephelus lanceolatus♂): Effects on growth, digestive and absorption capacities, inflammatory-related gene expression, and intestinal microbiota

A feeding trial was carried out to investigate the effects of dietary fermented rice protein (FRP) on growth, digestive and absorption capacities, inflammatory-related gene expression, and intestinal microbiota in juvenile hybrid groupers (Epinephelus fuscoguttatus♀ × Epinephelus lanceolatus♂). A fish meal (FM)-based diet was used as a control for comparison with diets in which FM was replaced by FRP at percentages of 10 % (FRP10), 30 % (FRP30), and 50 % (FRP50). Each diet was fed to triplicate groups of fish for 56 days. We observed no significant differences in weight gain rate, specific growth rate, and protein productive value between the FM and FRP10 groups, but significantly lower rates in the FRP30 and FRP50 groups. The activities of the intestinal digestive enzymes (amylase, trypsin, and pepsin) and brush border enzymes (Na+/K+-ATPase, creatine kinase, and γ-glutamyl transpeptidase) were higher in the FRP-containing groups than in the FM group. The expression levels of immune-related genes (TLR22, MyD88, TNF-α, IL-2, IL-6, IL-8, and TGF-β1) were all down-regulated in FRP-fed fish. Intestinal microbiota showed no significant differences in alpha diversity among dietary groups. At the genus level, FRP-containing groups had lower relative abundances of Bacteroides and Enterococcus than the FM group. In conclusion, 10 % of the FM protein in the feed can be replaced by FRP without adverse effects on nutritional status. Replacing FM with FRP in the feed suppresses inflammatory function in hybrid groupers. It also has a critical influence on microbial profiles but not on diversity.

Using unessential sulfur amino acids to overcome methionine deficient diets on rice field eel (Monopterus albus)

An eight-week feeding trial was conducted using sulfur amino acids to overcome methionine deficient diets on rice field eel Monopterus albus (initial weight 25.12 ± 0.51 g). Six isonitrogenous and isoenergetic experimental formulations included 55% fish meal group (FM, a reference), 22% fish meal group (D0), and the rest four diets (22% fish meal) supplemented with 2 g/kg of taurine (DTau), methionine (DMet), cysteamine hydrochloride (DCsh) and cystine (DCys), respectively. Compared with FM, the growth performance of M. albus was markedly declined in D0 (P < 0.05); while the growth performance of M. albus in DMet, DCsh and DCys were remarkably higher than D0 (P < 0.05), and these groups were indifference with FM (P > 0.05). Compared with FM, the highest amount of hepatic vacuoles was observed in D0, while the proportions of vacuoles were lower in DMet, DCsh and DCys groups than that in D0, dietary sulfur amino acids also have improved hepatic transaminase and the ability of amino acid metabolism. Compared with FM, muscular texture, density and diameters of muscle fibres were significantly decreased in D0 (P < 0.05); while muscular texture were significantly increased in DCsh and DCys (P < 0.05). Compared with D0, dietary sulfur amino acids improved diameters of the muscle fibres. Myocyte myogenic regulatory (Mrf4, MyoD2, Myog and Mrf4) and myocyte enhancer factors (MEF2b and MEF2c) mRNA expression in D0 were markedly lower than that in FM (P < 0.05), compared with D0, the expression of Mrf4 and MEF2b in DMet were significantly up regulated (P < 0.05); the expressions of Mrf4, MyoD2 and MEF2b in DCsh were markedly higher than that in D0 (P < 0.05), MyoD2, Myog, MEF2b and MEF2c in DCys also were remarkably higher than that in D0 (P < 0.05). Overall, our study indicated that dietary methionine, taurine, cysteamine hydrochloride and cystine in low fish meal diet could improve amino acids metabolism and muscle growth for M. albus, moreover, cysteamine hydrochloride and cystine overcame methionine deprivation partly.

Partial fishmeal protein replacement with peptides from swine blood modulates the nutritional status, immune response, and intestinal microbiota of hybrid groupers (female Epinephelus fuscoguttatus× male E. lanceolatus)

This study investigated the effects of replacing fish meal (FM) protein with peptides from swine blood (PSB) on the growth, digestion, and absorption capacity of hybrid groupers (female Epinephelus fuscoguttatus × male Epinephelus lanceolatus). It also analyzed their inflammatory-related gene expression, and intestinal microbiota. Four isonitrogenous and isolipidic experimental feeds were formulated to replace 0% (FM), 25% (PSB25), 50% (PSB50), and 75% (PSB75) of the FM protein with PSB. Each experimental diet was fed to triplicate groups of 30 hybrid grouper juveniles for 8 weeks. No significant differences in the weight gain and specific growth rates were found among the FM, PSB25, and PSB50 groups. The intestinal digestive enzyme (lipase, amylase, trypsin, and pepsin) and brush border enzyme (Na+/K+-ATPase, creatine kinase, and γ-glutamyl transpeptidase) activities showed no significant differences among the FM, PSB25, and PSB50 groups. Meanwhile, trypsin, pepsin. Creatine kinase, and γ-glutamyl transpeptidase activities in the PSB group were significantly higher than those of the FM group. No significant differences in the expression levels of the toll-like receptor 21 (TLR21), myeloid differentiation factor 88 (MyD88), and inflammatory cytokines (TNF-α, IL-2, IL-8, and IL-10) were observed among the four groups. The intestinal microbiota results showed no significant differences in alpha diversity among the four groups. At the genus level, at the genus level, Lactobacillus relative abundance was significantly reduced in the PSB10 group compared to that in the FM group. However, no significant differences were found among the FM, PSB50, and PSB75 groups. However, no significant differences were found among the FM, PSB50, and PSB75 groups. These results demonstrated that up to 50% of the FM protein in the feed can be replaced by PSB without adversely affecting the nutritional status and inflammatory response in hybrid groupers. Replacing FM with PSB significantly influences the microbial profile but not the diversity

Anti-anaemic effects of Moringa oleifera seeds (Lam) in protein energy malnourished rats

The effects of defatted Moringa oleifera seed (L) on haemotological indices and body weight was evaluated in rat model of Protein Energy Malnutrition (PEM). Protein Energy Malnutrition is associated with muscle degeneration and anaemia. Protein Energy Malnutrition (PEM) was induced in fifteen (15) rats by feeding them with low protein diet (3% fish meal protein) and water for twenty eight days. Five (5) rats served as positive control (Group A) received commercial feed containing 21% crude protein. The PEM rats were assigned to three groups namely B, C and D. Group B and C were fed with recovery diets ad libitum for another twenty eight days. Group B received feed containing 20% Fishmeal protein and Group C received feed containing 20% defatted M. oleifera seed. Group D were Protein-energy malnourished rats maintained on protein deficient diet (3% fish meal protein). Protein energy malnourished rats had significantly reduced (p&lt;0.05) body weight and haematological indices with exception of the Mean Capsular Volume (MCV) and Mean Capsular Haemoglobin (MCH) which significantly (p&lt; 0.05) increased. Phenotypical examination revealed that PEM animals had characteristic typical of catabolic states, which include, retarded growth, loss of hair, scaly tail etc. The recovery diets containing 20% fishmeal protein or 20% M. oleifera in place of 3% fishmeal caused significant (p&lt;0.05) increase in the Haematological Indices (with exception of MCV and MCH which decreased significantly) and body weight when compared with the malnourished group D. The study support the claims that PEM can cause muscle degeneration and disturbance to haematological parameters. Furthermore, supplementation of diet with M. oleifera seeds ameliorate muscle degeneration and anaemia in PEM rats comparatively similar to 20% fish meal.