Effects Of Dietary Mannan Oligosaccharides Research Articles

Effect of dietary mannan oligosaccharide inclusion on production parameters of Farfantepenaeus aztecus cultured in a biofloc system

AbstractThe effects of dietary mannan oligosaccharide (MOS) supplementation in a biofloc system on growth performance, whole‐body proximate composition, whole‐body fatty acids, nonspecific immune parameters, antioxidant enzyme activities, digestive enzyme activity, and gut microbiota of brown shrimp, Farfantepenaeus aztecus, were investigated. Shrimp were fed five diets containing different levels of MOS doses (MOS0: basal diet, MOS1: 0.1%, MOS2: 0.2%, MOS3: 0.3%, and MOS4: 0.4%) during the 90‐day trial. The results indicated that all MOS‐supplemented shrimp showed significantly higher growth rates and better feed utilization than shrimp fed the control diet. Experimental diets had varying effects on the nonspecific immune parameters and antioxidant enzyme activities, indicating that MOS supplementation resulted in significant differences in the parameters except for respiratory burst activity. Significantly higher protease activity was observed in shrimp fed MOS1 and MOS2 diets compared with MOS0, MOS3, and MOS4 diets. Shrimps fed MOS2 and MOS3 diets had the highest lipase and amylase activities among all groups. Proteobacteria were the most abundant phylum in all groups and were higher at increasing MOS doses. In conclusion, these results suggest that supplementing the diet of brown shrimp in the biofloc system with 3 g kg−1 of MOS may improve production parameters.

Effects of dietary mannan oligosaccharides and coated calcium butyrate on performance, carcass parameters, blood biochemistry and meat quality of growing Japanese quails

Aim of study: Despite previous research into mannan oligosaccharides (MOS) and calcium butyrate coated with palm oil (CCB) in poultry, there is a notable gap in the literature regarding the effects of these feed additives, either individually or in combination, on the growth performance, carcass values, blood biochemistry, immune response, and meat quality of growing Japanese quails. Area of study: Türkiye Material and methods: A total of 168 mixed-sex one-day-old quails were randomly allocated to one of four treatment groups, with each group containing 7 birds per cage. The control group was fed a basal diet, while the treatment groups received the following additives: 1 g/kg of CCB, 2 g/kg of MOS, and a combination of MOS+CCB added to the basal diet, respectively. Main results: None of the treatments had a significant impact on performance, relative organ weights, total protein, albumin, globulin, total cholesterol, high-density lipoprotein cholesterol, and lipoprotein lipase concentrations in blood serum, or humoral immunity on day 28. However, the inclusion of MOS and CCB in the diet, either individually or in combination, increased carcass yield and reduced low-density lipoprotein cholesterol and triglyceride levels in the blood serum. Additionally, these additives helped maintain optimal pH levels and lower malondialdehyde concentrations in the breast meat. Moreover, the combination of MOS + CCB significantly improved water holding capacity and antibody titers against the Newcastle Disease vaccine on day 42 in Japanese quails. Research highlights: The natural feed additives CCB and MOS contribute to enhanced carcass yield, improved meat quality, and strengthened humoral immunity, while simultaneously lowering lipid values in the bloodstream.

Comparative Expression Profiling Reveals the Regulatory Effects of Dietary Mannan Oligosaccharides on the Intestinal Immune Response of Juvenile Megalobrama amblycephala against Aeromonas hydrophila Infection.

Mannan oligosaccharides (MOS) are functional oligosaccharides with beneficial effects on the non-specific immunity of Megalobrama amblycephala, but systematic studies on the immunomodulatory mechanisms of MOS are still lacking. To investigate the protective mechanisms of three different levels of dietary MOS supplementation on the intestinal immunity of juvenile M. amblycephala, comparative digital gene expression (DGE) profiling was performed. In this study, 622 differentially expressed genes (DEGs) were identified, while the similar expression tendency of 34 genes by qRT-PCR validated the accuracy of the DGE analyses. Gene Ontology (GO) enrichment revealed that the DEGs were mainly enriched in two functional categories of biological process and molecular function. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the DEGs were mainly related to complement and coagulation cascades, coagulation cascades, platelet activation, natural killer cell mediated cytotoxicity, Fc gamma R-mediated phagocytosis and antigen processing and presentation. In addition, the pro-inflammatory, apoptosis and tight junction-related genes were more significantly up-regulated upon infection in the dietary MOS groups to enhance host immune functions and maintain the stability of the intestinal barrier. These results will be helpful to clarify the regulatory mechanism of MOS on the intestinal immunity of M. amblycephala and lay the theoretical foundation for the prevention and protection of fish bacterial diseases.

Effects of dietary mannan oligosaccharides on growth, non-specific immunity, and intestinal health in juveniles of the Japanese sea cucumber (Apostichopus japonicus)

Effects of dietary mannan oligosaccharides on growth, non-specific immunity, and intestinal health in juveniles of the Japanese sea cucumber (Apostichopus japonicus)

Effects of Dietary Mannan Oligosaccharides on Non-Specific Immunity, Intestinal Health, and Antibiotic Resistance Genes in Pacific White Shrimp Litopenaeus vannamei.

This study was conducted to comprehensively investigate the beneficial effects of a mannan oligosaccharide product (hereinafter called MOS) on Litopenaeus vannamei and optimum level of MOS. Five isonitrogenous and isolipid diets were formulated by adding 0%, 0.02%, 0.04%, 0.08%, and 0.16% MOS in the basal diet. Each diet was randomly fed to one group with four replicates of shrimp in an 8-week feeding trial. The results showed that dietary MOS improved the growth performance and the ability of digestion of shrimp. Dietary MOS significantly increased the activity of total superoxide dismutase, catalase, and glutathione peroxidase and decreased the content of malondialdehyde in plasma of shrimp. Dietary MOS significantly increased the activity of alkaline phosphatase and lysozyme in plasma and the hemocyte counts. Dietary MOS significantly upregulated the expression of Toll, lysozyme, anti-lipopolysaccharide factor, Crustin, and heat shock protein 70 in the hepatopancreas. And dietary MOS significantly upregulated the expression of intestinal mucin-2, mucin-5B, and mucin-19, while it decreased the expression of intestinal mucin-1 and macrophage migration inhibitory factor. Dietary MOS improved the bacterial diversity; increased the abundance of Lactobacillus, Bifidobacterium, Blautia, and Pseudoalteromonas; and decreased the abundance of Vibrio in the intestine. Shrimp fed MOS diets showed lower mortality after being challenged by Vibrio parahaemolyticus. Notably, this study found a decrease in antibiotic resistance genes and mobile genetic elements after MOS supplementation for the first time. The present results showed that diet with MOS supplementation enhanced the organismal antioxidant capacity and immunity, improved intestinal immunity, optimized intestinal microecology, mitigated the degree of antibiotic resistance, and increased the resistance to V. parahaemolyticus in L. vannamei, especially when supplemented at 0.08% and 0.16%.

Protective effects of dietary mannan oligosaccharide on heat stress-induced hepatic damage in broilers.

Heat stress is a major concern in broiler's production, which can damage liver of broilers. This study investigated the protective effects of mannan oligosaccharide (MOS) on heat stress-induced hepatic injury in broilers. A total of 144 day-old male chicks were allocated into three treatment groups. Broilers raised under normal ambient temperature were fed a basal diet (control group), and broilers under heat stress (32-33°C for 8h daily) were given the basal diet supplemented without MOS (heat stress group) or with 1g/kg MOS (MOS group) for 42days. Compared with the control group, heat stress reduced liver weight, whereas increased aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in the serum. It also reduced glutathione peroxidase (GSH-Px) activity in the serum and liver, GSH content, and superoxide dismutase (SOD) activity in the liver, but increased malondialdehyde (MDA) concentration in the serum and liver. Dietary MOS decreased serum ALT activity in heat-stressed broilers. MOS inclusion also decreased serum MDA content, but elevated hepatic GSH-Px and SOD activities, with MDA content and GSH-Px activity still being different from the control group, and SOD activity being similar to the control group. Heat stress increased concentrations of tumor necrosis factor α (TNF-α) in the serum and liver, interleukin-1β (IL-1β) in the liver, and mRNA abundances of HSP70, TLR4, MyD88, TNF-α, and IL-1β in the liver of broilers. Serum TNF-α content and mRNA abundances of hepatic TLR4 and TNF-α in MOS group were lower than the heat stress group, whereas these indexes were still higher than the control group. Our results indicated that dietary MOS ameliorated hepatic damage in heat-stressed broilers through alleviation of oxidative stress and inflammation.

Mannan oligosaccharides improved growth performance and antioxidant capacity in the intestine of on-growing grass carp (Ctenopharyngodon idella)

This study evaluates the effects of dietary mannan oligosaccharides (MOS) supplementation on growth performance and antioxidant capacity, as well as investigates its related signalling molecule mechanism in the intestine of on-growing grass carp (Ctenopharyngodon idella). A total of 540 on-growing grass carp (215.85 ± 0.30 g) were fed six diets containing graded levels of MOS supplementation (0, 200, 400, 600, 800 and 1000 mg kg−1) for 60 days. Subsequently, a challenge test was conducted by injection of Aeromonas hydrophila for 14 days. The results showed that (1) appropriate dietary MOS supplementation improved growth performance and enhanced disease resistance (2) appropriate dietary MOS supplementation relieved oxidative damage by decreasing the content of reactive oxygen species (ROS), and oxidative damage biomarker protein carbonyl (PC) and malondialdehyde (MDA). (3) appropriate dietary MOS supplementation enhanced antioxidant capacity by increasing enzyme activities [except manganese superoxide dismutase (MnSOD)] and corresponding gene expression (except MnSOD). (4) appropriate dietary MOS supplementation positively regulated antioxidant function related to MR/PKCδ/Nrf2/Keap1b (not Keap1a in the DI, not PKCα and PKCε in three intestinal segments) signalling pathway. In conclusion, the present study has demonstrated that dietary MOS supplementation could enhance fish intestine antioxidant capacity. Finally, based on the quadratic regression analysis for the percent weight gain (PWG), against enteritis morbidity, and the MDA, PC and ROS contents (in the DI) of on-growing grass carp, the MOS dosage was estimated to be 428.5, 499.1, 536.2, 561.7 and 550.9 mg kg−1 diet, respectively.

Effects of dietary mannan oligosaccharide supplementation on growth performance, antioxidant capacity, non-specific immunity and immune-related gene expression of juvenile hybrid grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀)

The present study was conducted to investigate the effects of dietary mannan oligosaccharide (MOS) supplementation on growth performance, antioxidant capacity, non-specific immunity and immune-related gene expression in juvenile hybrid grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀). A basal diet supplemented with MOS (0, 0.3%, 0.6%, 1.0% and 2.0%) was fed to juvenile hybrid grouper for 9 weeks. Results showed that there were no significant differences in feed intake, hepatosomatic index, spleen index or survival among all groups (P > .05). However, antioxidant analyses showed that hybrid grouper fed with MOS supplementation had significantly enhanced total antioxidant capacity (T-AOC) and superoxide dismutase (SOD). Non-specific immunity evaluation showed that hybrid grouper fed with MOS supplementation had significantly enhanced respiratory burst activity (RB), acid phosphatase activity (ACP) and lysozyme activity (LZM) (P < .05). Moreover, dietary MOS supplementation also enhanced morphological integrity of intestine (muscle thickness, villus length and villus width) (P < .05). Furthermore, in the intestine and liver of juvenile hybrid grouper fed dietary MOS, expression of immune-related genes Interleukin 8 (IL-8), Transforming growth factor β1 (TGF-β1), Target of rapamycin (TOR) and Toll-like receptor 3 (TLR3) was upregulated, whereas Kelch-like-ECH-associated protein 1 (Keap1), IκB kinase α (IKKα) and the apoptosis-related genes (p53 and Caspase-3) were down-regulated. After challenge with Vibrio harveyi, significantly higher post-challenge survival rate was observed in 0.6% MOS supplemented group than the control group (P < .05). These results indicate that dietary MOS supplementation does not improve growth performance or feed utilization of juvenile hybrid grouper; however, it can promote intestinal health and immunological status—by improving intestinal morphological integrity, enhancing antioxidant capacity and non-specific immunity, increasing immune-related gene expression and decreasing apoptosis-related gene expression in the intestine and liver.

Feeding European sea bass (Dicentrarchus labrax) juveniles with a functional synbiotic additive (mannan oligosaccharides and Pediococcus acidilactici): An effective tool to reduce low fishmeal and fish oil gut health effects?

The aim of this study was to assess the effects of dietary mannan oligosaccharides (MOS), Pediococcus acidilactici or their conjunction as a synbiotic in low fish meal (FM) and fish oil (FO) based diets on European sea bass (Dicentrarchus labrax) disease resistance and gut health. For that purpose, sea bass juveniles were fed one of 6 diets containing different combinations of MOS (Biomos® and Actigen©; Alltech, Inc., Kentucky, USA) and Pediococcus acidilactici (BAC, Bactocell®; Lallemand Inc., Cardiff, UK) replacing standard carbohydrates as follows (MOS (%)/BAC (commercial recommendation): high prebiotic level (HP) = 0.6/0, low prebiotic level (LP) = 0.3/0, only probiotic (B) = 0/+, high prebiotic level plus probiotic (HPB) = 0.6/+, low prebiotic level plus probiotic (LPB) = 0.3/+, control (C) = 0/0 for 90 days. After 60 and 90 days of feeding trial, fish were subjected to an experimental infection against Vibrio anguillarum. Additionally, inducible nitric oxide synthase (iNOS) and tumor necrosis factor α (TNFα) gut patterns of immunopositivity and major histocompatibility complex class II (MHCII), transforming growth factor β (TGF-β), regulatory T-cell subset (CD4+T lymphocytes) and effector T cell (CD8α+T lymphocytes) gene expression patterns in gut by in situ hybridization were evaluated after 90 days of feeding. The effects of both additives on posterior gut through Gut Associated Lymphoid Tissue (GALT) gene expression was also studied. Fish fed the prebiotic and its combination with P. acidilactici presented increased weight regardless of the dose supplemented after 90 days of feeding, however no effect was detected on somatic indexes. For posterior gut, morphometric patterns and goblet cells density was not affected by MOS, P. acidilactici or its combination. Anti-iNOS and anti-TNFα gut immunopositivity patterns were mainly influenced by MOS supplementation and not by its combination with P. acidilactici. MHCII-β, TCR-β, CD4 and CD8-α positive cells distribution and incidence was not affected by diet. Fish fed HP dose presented a clear up-regulation of TNF-α, cyclooxygenase-2 (COX-2), CD4 and IL10, whereas P. acidilactici dietary supplementation increased the number of interleukin-1β (IL1β) and COX-2 gene transcripts. Synbiotic supplementation resulted in a reduction of MOS-induced gut humoral proinflammatory response by increasing the expression of some cellular-immune system related genes. Fish mortality after V. anguillarum infection was reduced in fish fed LPB and LP diets compared to fish fed the non-suppelmented diet after 90 days of feeding.Thus, overall pointing to the combination of a low dose of MOS and P. acidilactici as synbiont (LPB) as a viable tool to potentiate European sea bass juvenile's growth and disease resistance when supplemented in low FM and FO diets.

Dietary mannan oligosaccharide improves growth performance, muscle oxidative status, and meat quality in broilers under cyclic heat stress

This study investigated the effects of dietary mannan oligosaccharide (MOS) supplementation on growth performance, serum corticosterone level, and antioxidant ability, meat quality as well as chemical composition of breast muscle in broilers exposed to cyclic heat stress (HS). 144 one-day-old male broiler chicks (Arbor Acres plus) were randomly allocated to 3 treatments with 6 replicates each. Broilers in the control and HS groups were fed a basal diet, and in the MOS group were given the basal diet supplemented with 1 g/kg MOS for 42 days, respectively. The temperature was maintained 32–33 °C for the first 3 days for all broilers, and it was gradually reduced by 3 °C per week to a final temperature of 20 °C in the control group, whereas it remained unchanged for 8 h and reduced to the same level to the control group for the remaining 16 h daily in the both HS and MOS groups. Compared with the control group, cyclic HS resulted in retarded growth performance and increased serum corticosterone level (P < 0.05). The supplementation of MOS promoted growth performance and reduced serum corticosterone concentration in broilers subjected to cyclic HS (P < 0.05). Cyclic HS increased drip loss48 h, cooking loss, malondialdehyde accumulation, and moisture content, whereas decreased pH24 h value, glutathione peroxidase (GSH-Px) activity, and crude protein content in the breast muscle (P < 0.05). In contrast, dietary MOS supplementation reduced drip loss48 h and malondialdehyde concentration, and increased GSH-Px activity in breast muscle compared with the HS group (P < 0.05). The results indicated that dietary MOS supplementation could improve growth performance, and oxidative status and meat quality of breast muscle in broilers under cyclic HS.

Growth optimization of marine diatom Amphora sp. by tailoring silica and nitrate concentration

Growth optimization of marine diatom Amphora sp. by tailoring silica and nitrate concentration

EFFECT OF SUPPLEMENTAL MANNAN OLIGOSACCHARIDE TO RABBIT DIETS ON PRODUCTIVE AND REPRODUCTIVE PERFORMANCE OF DOES DURING SUMMER SEASON IN EGYPT

The objective of this study was to evaluate the effects of dietary mannan oligosaccharide (Bio-Mos) supplementation on reproductive, productive performance and milk production of APRI line rabbit does under high ambient temperature. A total of 40 APRI line rabbit does, 8-9 months old, were divided into four experimental treatments (10 each). Rabbit does were fed ad libitum the basal diet supplemented without (control), with 0.5, 1 or 1.5 g mannan oligosaccharide (Bio-Mos) /kg diet. Animals were provided with water freely. The average daily temperature and relative humidity inside the rabbitry were 31.6±3.8 °C and 77.5±4.8%, respectively. Under heat stress conditions, does weight gain at gestation significantly increased (P<0.001) with increasing dietary MOS supplementation. Pregnant rabbit does given diet containing 1.5 g MOS /kg diet showed the highest weight gain than those fed other dietary MOS levels during the pregnancy period.Daily feed intake of pregnant and lactating rabbit does increased (P<0.05) with increasing dietary MOS level, where rabbit does fed diet containing 1.5 g MOS /kg diet recorded the highest values. The feed conversion ratio was significantly improved (P<0.001) with rabbit does fed diets containing different MOS level (0.5, 1.0 and 1.5 g) during lactation period. The mortality rate of the pups during the lactation period was higher in the control diet compared to diets with 0.5, 1.0 and 1.5 g MOS (32.11 % vs. 25.82, 18.37 and 17.77%; P<0.01, respectively), which could be due to lower milk yield of rabbit does fed unsupplemented diet. Rabbit does fed 1.0 and 1.5 g MOS/kg diet recorded the highest values of letters weights, during the first three weeks. The same trend was obtained at weaning. Rabbit does fed 1.5 g MOS/kg diet recorded the highest net revenue, followed by those fed 1.0 g MOS/kg diet. It could be concluded that supplementing MOS in rabbit does diet significantly improve the overall productive and reproductive performance of rabbits does during pregnancy and lactation periods, in addition to depressing the mortality of pups under high ambient temperature during summer season in Egypt. Therefore, it could be recommended providing rabbit does diet with MOS up to 1.5 g/kg diet is advisable in hot climates, Egypt.

Effects of dietary mannan oligosaccharides in early weaning diets on growth, survival, fatty acid composition and gut morphology of gilthead sea bream (Sparus aurata, L.) larvae

Early weaning of marine fish larvae with dry diets delays gut maturation and reduces growth rates. In juvenile and adult forms of several marine fish species, inclusion of dietary mannan oligosaccharides (MOS) improves gut integrity and functionality, but the effects of MOS inclusion in gilthead sea bream (Sparus aurata, L.) larval diets have not been addressed yet. Thus, this study assesses the effects of dietary MOS inclusion on survival, growth performance, gut morphology, feed acceptance and quality of gilthead sea bream larvae. For that purpose, 16 days post-hatched gilthead sea bream larvae were fed four graded levels of MOS (Biomos®, Alltech, Nicholasville, KY, USA) in weaning diets as follows: 0 g kg−1 MOS, 0.5 g kg−1 MOS, 1.5 g kg−1 MOS and 2 g kg−1MOS. Dietary MOS did not affect feed acceptance in gilthead sea bream larvae (P > 0.05). MOS supplementation was correlated in a dose-dependent way with higher larval survival (P = 0.026). After 15 days of feeding, dietary MOS increased whole larvae (P < 0.01) arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid. Gilthead sea bream larvae fed 2 g kg−1 MOS presented higher gut occupation with goblet cells after feeding compared with larvae fed the other dietary treatments. Overall, the results suggest that inclusion of MOS in early weaning diets for gilthead sea bream improves essential fatty acid utilization and may promote growth and final survival.

Effects of dietary mannan oligosaccharide on the growth, survival, intestinal morphometry and nonspecific immune response for Siamese fighting fish (Betta splendens Regan, 1910) larvae

A 28-day experiment was carried out to evaluate the effect of dietary prebiotic mannan oligosaccharide (MOS) on the growth, survival, intestinal morphometry and nonspecific immune response of the Siamese fighting fish ( Betta splendens Regan, 1910) larvae. The MOS supplementation levels evaluated was: 0, 2, 4 and 6 g kg -1 . Into 16 plastic aquaria (3 L) 240 larvae (4.21 ± 0.26 mm) were distributed at a density of 5 larvae L -1 . All larvae received live food for seven days, followed by a period of eight days of co-feeding (live food + inert diet) and, finally, 13 days of inert diet. At the end of feeding-trial, there were no significant differences between growth, survival, intestinal morphometry and alkaline phosphatase activity of larvae fed the control or MOS supplemented diets. However, the lysozyme activity in larvae fed 2 g MOS kg -1 was significantly higher compared to other treatments. For fish farming, the most beneficial effects of prebiotics reside in its ability to enhance the immune system of fish. In this context, this study revealed that, although the MOS supplementation has no effect on growth, survival and intestinal morphometry, 2 g MOS kg -1 supplementation for B. splendens larvae hint at a possible immunomodulatory effect, as evidenced by the increase in lysozyme activity

Combined effects of dietary mannan oligosaccharides and Pediococcus acidilactici and their combination in low fish meal and fish oil diets for European sea bass, Dicentrarchus labrax, juveniles

Low dietary levels of raw marine ingredients in marine fish species diets induce variable side-effects on fish growth performance, welfare and health, depending mainly on the terrestrial protein and oil source used, dietary levels and fish species studied. Particularly, high dietary levels of vegetable meals (VM) and oils (VO) blends, may induce intestinal dysfunction by altering tissue morphology, intestinal functionality, microbiota populations or gut associated lymphoid tissue (GALT) homeostasis. On the other hand, alternative feed ingredients such as prebiotics and probiotics have demonstrated to promote fish performance and disease resistance through potentiating GALT efficiency and functionality. Thus, the main objective of this study is to evaluate the effects of dietary mannan oligosaccharides (Biomos® and ActigenTM), Pediococcus acidilactici (BAC; Bactocell ®) and their combination in low FM and FO diets for european sea bass juveniles. Fish of 19.7±0.09g were distributed in 18 tanks and fed for 90 days six experimental diets with a low content of FM and FO, containing graded and combined levels of MOS and BAC as follows: HP; LP; B; HPB; LPB and C (Control). After 60 and 90 days of feeding, fish were sampled for growth, gut morphometry and histopathology, gut mucus production and expression of GALT related genes. Besides, samples were taken for gut iNOS and TNFα immunohistochemistry (IHQ) and for in situ hybridation (ISH) studies of MHCβ, TCRβ, CD4 and CD8. Fish fed diets HP, LP and LPB presented higher final weight. Two-way ANOVA attributed this effect to MOS regardless of dietary BAC inclusion. The use of prebiotic induced an increase on number of goblet cells in posterior gut (Fig.1). IHQ analyses performed against iNOS and TNFα showed the use of prebiotics induce an inflammatory-like pattern in the apical side of gut villi. Results for ISH showed that combined use of pre and probiotic induced a wider distribution of TCR-β marked cells, with special emphasis in the lamina propria. Expression of GALT-related genes, will be also discussed. Fig.1. Posterior gut (Alcian Blue-PAS). (a) LPB and (b) C diets t=90days. Note the higher number of goblet cell for fish fed LPB diet Acknowledgements: This study has been funded by the Spanish Ministry of Economy and Competitiveness, Project AGL2012-39919 (PROINMUNOIL)

Combined effects of dietary mannan oligosaccharides and total fish oil substitution by soybean oil on European sea bass (Dicentrarchus labrax) juvenile diets

This study evaluates the effects of dietary mannan oligosaccharides (MOS) on growth, tissue composition, fatty acid profiles and liver morphology of European sea bass (Dicentrarchus labrax) fed diets containing either soybean oil (SBO; SBOMOS) or fish oil (FO; FOMOS) as unique oil source for 8 weeks. Results showed that MOS supplementation enhanced specific growth rate, regardless of the oil source used, and that dietary oil source reduced fish length, regardless of dietary MOS supplementation. Dietary MOS favoured lipid accumulation in muscle and anterior intestine when supplemented in FO-based diets compared to fish fed SBO diet and reduces it in liver in relation to lower hepatocyte area, particularly in fish fed SBOMOS diet. Dietary MOS favoured liver and not muscular ∑n-3 PUFA, DHA, EPA and ARA deposition, when combined with FO but not when included in SBO-based diets. Thus, MOS dietary supplementation favours fish performance and helps to minimize the side effects derived from high dietary SBO supplementation on liver lipid accumulation and hepatocyte vacuolization, which could be of especial interest on long-term feeding trials; however, the effects on favoured deposition ∑n-3 PUFA are limited to FO-based diets.

Effects of Mannan Oligosaccharide and Serotonin on Molting, Growth, Body Composition and Hepatopancreas Histology of White Leg Shrimp Litopenaeus vannamei (Boone 1931)

The effects of dietary mannan oligosaccharide (MOS), serotonin (5 - HT) and the combination of both on molting, growth, survival, body composition, and hepatopancreas histology of the Pacific white shrimp Litopenaeus vannamei were investigated for 75 days. Dietary inclusion level of MOS at 3 g kg - 1 , serotonin at 20 mg k g - 1 , and both were tested in triplicate groups against a control diet lacking MOS or serotonin. The shrimps having an average initial weight of 1.35± 0.04 g attained to final weights an average of 10.71 control, 11.05 serotonin and 12.26 MOS respectively. A lthough survival rate was high (86%) in the shrimp fed MOS - supplemented diet, no statistical difference was found among the groups (P>0.05). The results indicate that inclusion of 3 g kg - 1 MOS into diet enhance shrimp survival, moulting rate, growth and FC R compared to the control. Serotonin inclusion at 20 mg/kg also improved the same parameters, but suppressed moulting rate in comparison to the other groups (P<0.05). Hepatopancreatic tissues were not affected by dietary treatments. Body composition (prot ein, lipid, ash and dry matter) of the shrimps were also similar in all the dietary groups. In conclusion, the current result s have demonstrated that MOS at 3.0 g kg - 1 inclusion level could be used as growth promoter in L. vannamei diets.

Enhanced intestinal epithelial barrier health status on European sea bass (Dicentrarchus labrax) fed mannan oligosaccharides

The study assesses the effects of dietary mannan oligosaccharides (MOS) in European sea bass (Dicentrarchus labrax) posterior intestinal lipid class composition and its possible relation to the potential prostaglandins production and Gut Associated Lymphoid Tissue (GALT) stimulation.Fish were fed 4 g kg−1 MOS (Bio-Mos® Aquagrade, Alltech, Inc., USA) for eight weeks. Fish fed MOS presented higher (P ≤ 0.05) weight gain, total length, and specific and relative growth rates than fish fed the control diet. Stimulated posterior gut of fish fed MOS showed higher (P ≤ 0.05) prostaglandins production than fish fed the control diet. Lipid class analyses of posterior gut revealed a reduction (P ≤ 0.05) in the neutral lipid fraction in fish fed MOS compared to fish fed the control diet, particularly due to a reduction (P ≤ 0.05) in triacylglycerols content. The polar lipid fraction increased (P ≤ 0.05) in fish fed MOS compared to fish fed the control diet, mainly due to an increase (P ≤ 0.05) in phosphatidylethanolamine and phosphatidylcoline contents.Light microscopy of posterior gut revealed increased number or goblet cells as well as higher level of infiltrated eosinophilic granulocytes for fish fed MOS. Transmission electron microscopy qualitative observations revealed a better preserved cytoarchitecture of the intestinal epithelial barrier in the posterior gut of fish fed MOS. Posterior gut of fish fed MOS presented more densely packed non-damaged enterocytes, better preserved tight junctions structure, healthier and more organized microvilli, and a higher presence of infiltrated lymphocytes and granulocytes compared fish fed the control diet.The present study indicates that dietary MOS enhances European sea bass posterior gut epithelial defense by increasing membrane polar lipids content in relation to a stimulation of the eicosanoid cascade and GALT, promoting posterior gut health status.

Effects on mortality and stress response in European sea bass, Dicentrarchus labrax (L.), fed mannan oligosaccharides (MOS) after Vibrio anguillarum exposure

The effects of dietary mannan oligosaccharides (MOS; 4 g kg(-1) ; Bio-Mos, Alltech Inc, USA) in diets for European sea bass, Dicentrarchus labrax (L.), juveniles in relation to disease and stress resistance, combining intestinal infection with Vibrio anguillarum and stress challenge by confinement, were assessed in this study. After 8 weeks of MOS supplementation, fish were exposed to a pathogen challenge test against V.anguillarum by direct gut inoculation combined with a confinement stressor panel. Cumulative mortality of fish fed MOS caused by anally inoculated V.anguillarum decreased from 66% to 12.5% and from 54.1% to 25% in infected and infected + stressed fish, respectively, compared to fish fed control diet. Results for European sea bass revealed a positive effect of MOS dietary inclusion on disease resistance, in terms of cumulative mortality, against gut inoculated V.anguillarum, as well as reduced effects of stress on microbiota diversity. Both of these findings, together with the enhanced innate immune response and the higher gut mucus production and density of eosinophil granulocytes in gut mucosa obtained in previous studies after MOS supplementation (Torrecillas etal. 2007, 2011a,b) suggest that general reinforcement of the innate immune system, and particularly of the intestinal barrier efficiency, is the main defence mechanism of European sea bass fed MOS against pathogenic microorganisms.

Effects of dietary mannan oligosaccharide on growth performance, gut morphology and stress tolerance of juvenile Pacific white shrimp, Litopenaeus vannamei

An 8-week feeding trial was conducted to investigate the effects of dietary mannan oligosaccharide (MOS) on growth performance, gut morphology, and NH3 stress tolerance of Pacific white shrimp Litopenaeus vannamei. Juvenile Pacific white shrimp (1080 individuals with initial weight of 2.52 ± 0.01 g) were fed either control diet without MOS or one of five dietary MOS (1.0, 2.0, 4.0, 6.0 and 8.0 g kg−1) diets. After the 8-week feeding trial, growth parameters, immune parameters, intestinal microvilli length and resistance against NH3 stress were assessed. Weight gain (WG) and specific growth rate (SGR) were significantly higher (P < 0.05) in shrimp fed 2.0, 4.0, 6.0 and 8.0 g kg−1 MOS-supplemented diets than shrimp fed control diet. WG and SGR of shrimp fed 2.0 g kg−1 MOS-supplemented diet was the highest (P < 0.05) in all experimental groups. Survival rate (SR) of shrimp was generally similar (P > 0.05) in all experimental groups. Compared with control group, TEM analysis revealed that 2.0, 4.0, 6.0 and 8.0 g kg−1 MOS supplementation could significantly increase (P < 0.05) the intestinal microvilli length of shrimp at the ultrastructural level. After NH3 stress for 24 h, SR of shrimp fed 2.0, 4.0, 6.0 and 8.0 g kg−1 MOS-supplemented diets was significantly higher (P < 0.05) than that of shrimp fed control diet. Phenoloxidase (PO) activity of 4.0 g kg−1 MOS-supplemented group was significantly higher (P < 0.05) than that of control group under normal conditions and NH3 stress. PO activity significantly decreased (P < 0.05) under NH3 stress than under normal conditions. Superoxide dismutase (SOD) activity of 4.0, 6.0 and 8.0 g kg−1 MOS-supplemented groups was significantly higher (P < 0.05) than that of control group under normal conditions. After NH3 stress for 24 h, SOD activity of all experimental groups also significantly decreased (P < 0.05) compared to normal conditions. These results clearly indicated that dietary MOS could improve growth performance and increase the resistance against NH3 stress in L. vannamei, and the 2.0–4.0 g kg−1 MOS supplementation was suitable for L. vannamei.