Comparative effects of soy protein concentrate, enzyme-treated soybean meal, and fermented soybean meal replacing animal protein supplements in feeds on growth performance and intestinal health of nursery pigs

BACKGROUND

Soy protein supplements, with high crude protein and less antinutritional factors, are produced from soybean meal by different processes. This study evaluated the comparative effects of various soy protein supplements replacing animal protein supplements in feeds on the intestinal immune status, intestinal oxidative stress, mucosa-associated microbiota, and growth performance of nursery pigs.

METHODS

Sixty nursery pigs (6.6 ± 0.5 kg BW) were allotted to five treatments in a randomized complete block design with initial BW and sex as blocks. Pigs were fed for 39 d in 3 phases (P1, P2, and P3). Treatments were: Control (CON), basal diet with fish meal 4%, 2%, and 1%, poultry meal 10%, 8%, and 4%, and blood plasma 4%, 2%, and 1% for P1, P2, and P3, respectively; basal diet with soy protein concentrate (SPC), enzyme-treated soybean meal (ESB), fermented soybean meal with Lactobacillus (FSBL), and fermented soybean meal with Bacillus (FSBB), replacing 1/3, 2/3, and 3/3 of animal protein supplements for P1, P2, and P3, respectively. Data were analyzed using the MIXED procedure in SAS 9.4.

RESULTS

The SPC did not affect the BW, ADG, and G:F, whereas it tended to reduce (P = 0.094) the ADFI and tended to increase (P = 0.091) crypt cell proliferation. The ESM did not affect BW, ADG, ADFI, and G:F, whereas tended to decrease (P = 0.098) protein carbonyl in jejunal mucosa. The FSBL decreased (P < 0.05) BW and ADG, increased (P < 0.05) TNF-α, and Klebsiella and tended to increase MDA (P = 0.065) and IgG (P = 0.089) in jejunal mucosa. The FSBB tended to increase (P = 0.073) TNF-α, increased (P < 0.05) Clostridium and decreased (P < 0.05) Achromobacter and alpha diversity of microbiota in jejunal mucosa.

CONCLUSIONS

Soy protein concentrate, enzyme-treated soybean meal, and fermented soybean meal with Bacillus could reduce the use of animal protein supplements up to 33% until 7 kg body weight, up to 67% from 7 to 11 kg body weight, and entirely from 11 kg body weight without affecting the intestinal health and the growth performance of nursery pigs. Fermented soybean meal with Lactobacillus, however, increased the immune reaction and oxidative stress in the intestine consequently reducing the growth performance.

Partial or complete replacement of fishmeal with fermented soybean meal on growth performance, fecal composition, and meat quality in broilers

The current study was aimed to examine the effect of partial or complete replacement of fishmeal (FM) with fermented soybean meal (FSBM) on growth performance, fecal composition, and meat quality in broiler chickens. A total number of 240 one-day-old broiler chicks were randomly allotted into four dietary treatments with six replications and ten birds per one pen. Dietary treatments were followed as; 1) Diet incorporated with 4% FM without FSBM (Control), 2) Diet incorporated with 3% FM and 2% FSBM (FSBM2), 3) Diet incorporated with 2% FM and 3% FSBM (FSBM3) and 4) Diet incorporated with 4% FSBM without FM (FSBM4). Body weight and feed intake were recorded weekly for 35 days of the experimental period. Moreover, fecal samples were collected to evaluate moisture, ash, nitrogen, calcium and phosphorus content on day 21 post-hatch. On day 35, two birds were sacrificed from each pen to measure meat quality parameters and visceral organ weights. Results revealed that, no dietary treatment effect (p > 0.05) was observed either in both body weight or average daily gain of broilers within the entire experimental period while broilers fed FSBM2 increased (p < 0.05) average daily feed intake by 10.07% whereas FSBM4 improved (p < 0.05) feed efficiency ratio by 8.45% compared to birds fed other dietary treatments on day 7 post-hatch. Besides, birds fed FSBM3 obtained the improved (p < 0.05) feed conversion ratio over the birds fed control diet by 7.51% from hatch to day 35 post-hatch (1.60 vs. 1.73). Nevertheless, no difference (p > 0.05) was detected on visceral organ weight, proximate composition and physicochemical characteristics of meat while broilers offered FSBM4 obtained the lowest (p < 0.05) calcium and phosphorous in faces (2.27% and 1.21% respectively) over those offered control feed and other FSBM treatments. In conclusion, FSBM would be a better replacement for ousting FM partially or completely in broiler diet as it did not impair the growth performance and meat quality while reducing the calcium and phosphorous excretion in broilers for 35 days post-hatch.

Dietary fermented soybean meal replacement alleviates diarrhea in weaned piglets challenged with enterotoxigenic Escherichia coli K88 by modulating inflammatory cytokine levels and cecal microbiota composition

BACKGROUND

Impaired gut microbiota leads to pathogenic bacteria infection, pro-inflammatory response and post-weaning diarrhea. Enterotoxigenic Escherichia coli (ETEC) K88 is a major cause of post-weaning diarrhea in weaned piglets. Fermented soybean meal (FSBM) could relieve diarrhea, alleviate inflammatory response, and modulate gut microbiota of weaned piglets. We used ETEC K88-challenged weaned piglet model to investigate the effects of FSBM on the growth performance, inflammatory response and cecal microbiota. Twenty-four crossbred piglets (6.8 ± 0.5 kg; 21 ± 2 days of age) were allotted into 2 treatment fed the diets with or without FSBM (6% at the expense of soybean meal). Six weaned piglets in each diet treatment were challenged by ETEC K88 (1 × 109 CFU/piglets) on day 15. The experimental period lasted for 20 days.

RESULTS

The ETEC K88 challenge decreased (p < 0.05) fecal consistency and plasma interleukin-10 (IL-10) concentration, while increased (p < 0.05) average daily feed intake (ADFI) and plasma tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin 6 (IL-6) concentrations. After ETEC K88 challenge, dietary FSBM replacement increased (p < 0.05) final body weight (BW), average daily gain (ADG), ADFI, and fecal consistency, but decreased feed conversion ratio (FCR). The plasma IL-10 concentration of weaned piglets fed FSBM was higher (p < 0.05), while IL-1β, IL-6 and TNF-α concentrations were lower (p < 0.05). Dietary FSBM replacement attenuated the increase of plasma TNF-α concentration and the decrease of ADG induced by ETEC K88 challenge (p < 0.05). High-throughput sequencing of 16S rRNA gene V4 region of cecal microbiota revealed that ETEC K88 challenge increased (p < 0.05) Campylobacter relative abundance on genus level. Dietary FSBM replacement resulted in higher (p < 0.05) relative abundances of Bacteroidetes and Prevotellaceae_NK3B31_group, and lower (p < 0.05) relative abundances of Proteobacteria and Actinobacillus. Furthermore, dietary FSBM replacement relieved the increase of Escherichia-Shigella relative abundance in weaned piglets challenged by ETEC K88 (p < 0.05).

CONCLUSIONS

Dietary FSBM replacement improved growth performance and alleviated the diarrhea of weaned piglets challenged with ETEC K88, which could be due to modulation of cecal microbiota composition and down-regulation of inflammatory cytokines production.

Effects of dietary raw or Enterococcus faecium fermented soybean meal on growth, antioxidant status, intestinal microbiota, morphology, and inflammatory responses in turbot (Scophthalmus maximus L.)

Fermentation has been reported to improve the utilization of plant ingredients including soybean meal (SBM) by fish, but the detailed mechanism is still poorly understood. This study compared the effects of partial replacement of fish meal (FM) protein with SBM or Enterococcus faecium fermented SBM (EFSM) on the growth, antioxidant status, intestinal microbiota, morphology, and inflammatory responses in turbot (Scophthalmus maximus L.). The FM-based diet was used as the control (CONT). Two experimental diets were formulated in which 45% of the FM protein was replaced with SBM or EFSM. Each diet was fed to triplicate groups of fish (7.57 ± 0.01 g) twice daily for 79 d. Inferior growth performance was observed in SBM group, however, no significant depression was observed in EFSM group compared to the CONT group. The CONT group had the highest values of lysozyme, complement component 3, total antioxidant capacity, superoxide dismutase and catalase, followed by the EFSM group, and the lowest in SBM group. The malondialdehyde content was lowest in the CONT group, followed by the EFSM group, and was highest in the SBM group. Gut morphology showed that SBM diet induced alterations typical for intestinal inflammation including decreased villus and microvillus height, and increased width and inflammatory cell infiltration of the lamina propria. However, the EFSM group alleviated such SBM-induced intestinal pathological disruption. Paralleled with the morphological symptoms, the inflammatory gene expression levels of tumor necrosis factor alpha, interleukin-1 beta and interleukin-8 were highest in the SBM group, followed by the EFSM group, and were lowest in the CONT group. Furthermore, the intestinal microbiota analysis revealed that EFSM group had an overall more similar microbiota with CONT group than SBM group. Specifically, compared with the SBM group, EFSM group significantly enhanced the probiotics Lactobacillus and anti-inflammatory bacterium Faecalibaculum, and inhibited the Vibrio. Collectively, this study indicated that Enterococcus faecium fermentation effectively counteracted the negative effects of SBM by enhancing antioxidant capacity, suppressing inflammatory responses, and modulating gut microbiota in turbot.

Beneficial influences of dietary Aspergillus awamori fermented soybean meal on oxidative homoeostasis and inflammatory response in turbot (Scophthalmus maximus L.)

High levels of soybean meal (SBM) in aquafeed leads to detrimental inflammatory response and oxidative stress in fish. In the present study, fermentation with Aspergillus awamori was conducted to explore the potential effects on improving the nutritional quality of soybean meal and the health status of turbot. A 63-day feeding trial (initial weight 8.53 ± 0.11 g) was carried out to evaluate the utilization of fermented soybean meal (FSM) by juvenile turbot. 0% (FM, control), 30% (S30, F30), 45% (S45, F45), and 60% (S60, F60) of fish meal were replaced with SBM or FSM, respectively. As the results showed, fermentation significantly reduced the contents of anti-nutritional factors in SBM, including raffinose (-98.8%), glycinin (-98.5%), β-conglycinin (-97.4%), trypsin inhibitors (-80%) and stachyose (-80%). A depression of fish growth performance and activities of superoxide dismutase and lysozyme were observed in S45 and S60 groups, while these inferiorities were only observed in F60 group. Meanwhile, fermentation also improved the heights of enterocytes and microvillus significantly in the F45 and F60 groups compared with those in SBM. An induced expression of anti-inflammatory cytokine transforming growth factor-β and depression of pro-inflammatory cytokines tumor necrosis factor-α and interleukin-1β in the distal intestine were observed in the F45 and F60 groups. Taken together, this study indicated that fermentation with Aspergillus awamori could improve the replacement level with soybean meal from 30% to 45% in turbot.

Horizontal transfer of vanA between probiotic Enterococcus faecium and Enterococcus faecalis in fermented soybean meal and in digestive tract of growing pigs

Background

The aim of this study was to investigate the intergeneric transfer of vancomycin resistance gene vanA between probiotic enterococci in the fermentation progress of soybean meal and in the digestive tract of growing pigs. One vanA genotype vancomycin resistant E. faecium strain, Efm4, and one chloramphenicol-resistant E. faecalis strain, Efs2, were isolated from twenty-nine probiotic basis feed material / additive samples. For in vitro conjugation, Efm4 and Efs2 were used as starter to ferment soybean meal. For in vivo conjugation, thirty growing pigs were randomly assigned to five groups (n = 6), treated with a basic diet, or supplemented with 10% fermented soybean meal, 1% Efm4, 5% Efs2 or a combination of 1% Efm4 + 5% Efs2 for 7 d, respectively. Fecal samples of pigs in each group were collected daily for the isolation and dynamic analysis of Efm4, Efs2 and transconjugants. The sequence types (STs) of Efm4, Efs2 and transconjugants were analyzed by multilocus sequence typing (MLST). The vanA harboring plasmid in Efm4 and transconjugants was analyzed by S1-pulsed field gel electrophoresis (PFGE) and further verified by multiple alignments.

Results

The results showed that, in FSBM, transconjugants were detected 1 h after the fermentation, with a conjugation frequency of ~ 10^- 3 transconjugants / recipient. Transconjugants proliferated with Efm4 and Efs2 in the first 8 h and maintained steadily for 10 d till the end of the experiment. Additionally, in vivo experiment showed that transcojugants were recovered in one of six pigs in both FSBM and Efm4 + Efs2 groups, with conjugation frequency of ~ 10^- 5 and ~ 10^- 4, respectively. MLST revealed the ST of Efm4, Efs2 and transconjugants was ST1014, ST69 and ST69, respectively. S1-PFGE confirmed the existence of the vanA-harboring, 142,988-bp plasmid, which was also a multi-drug resistant plasmid containing Tn1546-like transposon.

Conclusions

The findings revealed the potential safety hazard existing in the commercial probiotic enterococci in China, because the horizontal transfer from farm to fork could potentially pose a safety risk to the public.

Replacement of fish meal with Bacillus pumillus SE5 and Pseudozyma aphidis ZR1 fermented soybean meal in diets for Japanese seabass (Lateolabrax japonicus)

This study examined the effects of replacing fish meal (FM) with three different types of soybean meal (SM) including untreated SM, Bacillus pumillus SE5 (BP) fermented SM (BPFSM) and Pseudozyma aphidis ZR1 (PA) fermented SM (PAFSM) in diets for Japanese seabass (Lateolabrax japonicus). A basal diet was formulated using FM (FM diet), and six other diets were produced by substituting 40 or 80% of FM with SM, BPFSM or PAFSM (SM40, SM80, BPFSM40, BPFSM80, PAFSM40 and PAFSM80 diets). Each diet was fed to triplicate groups of fish (7.14 ± 0.05 g) twice daily for eight weeks. Replacing 40% of FM with SM sources did not significantly influence growth (P > 0.05), while increasing the substitution level to 80% led to reduced growth rates (P < 0.05). The groups received SM80 and PAFSM80 diets showed significantly higher feed conversion ratio and lower protein digestibility than FM group. Furthermore, notably lower dry matter digestibility was detected in SM80 group. Remarkably lower serum total antioxidant capacity was found in the SM80 group, and catalase activity did not significantly differ between FM and BPFSM40 groups. Serum malondialdehyde concentration was enhanced by increasing FM replacement level and the highest value was observed in the SM80 fed fish. FM and PAFSM40 groups showed significantly higher lysozyme activity than the SM80 group. Fish fed the BPFSM40 diet exhibited the highest complement C3 activity and the lowest value was observed in the SM80 group. Expression of lysozyme gene in spleen was down-regulated in the SM80 group, and no significant difference in expression of C3 gene was found among FM, BPFSM40 and PAFSM40 groups. Digestive enzymes activity and gut morphology were significantly influenced by FM replacement. Expression of HSP70 and pro-inflammatory genes including TNF-α and IL-1β were up-regulated by FM replacement and relatively lower expression levels were found by using fermented SM. An opposite trend was observed for the anti-inflammatory TGF-β gene expression. Serum d-lactate concentration was significantly increased by replacing 80% of FM with any of the SM sources. These findings indicated that using fermented SM, particularly BPFSM, beneficially influences feed utilization, antioxidant capacity, innate immunity and gut health in juvenile Japanese seabass.

Dietary soybean antigen impairs growth and health through stress-induced non-specific immune responses in Pacific white shrimp, Litopenaeus vannamei

In order to compare the effect of substituting fish meal with fermented soybean meal and soybean meal, and confirmed whether the benefit from the two feed materials was related to the content of inclusive soybean antigen protein, two experiments were designed. In experiment 1, one of the two practical diets contained 24.9% soybean meal (SBM), the other one containing 8% fermented soybean meal and 16.95% soybean meal (FSBM); in experiment 2, two semi-purified diets were included with high antigen protein (SPD1) and low antigen protein (SPD2) approximately equal to SBM and FSBM group respectively in experiment 1. Diets were fed to Litopenaeus vannamei (initial weight: 7.48 ± 0.24 g) for 60 days. The results showed that in experiment 1, growth performance was not significantly different between two groups, the enzyme activity (AKP, AST, ALT, SOD and LZM) and mRNA expression levels of TLR, LZM, IMD and HSP70 were significantly higher in the SBM group; In experiment 2, weight gain and specific growth rate were significantly higher in the SPD2 group, while higher activities of AKP, ALT and LZM, lower expression levels of TLRmRNA, LZMmRNA and IMDmRNA and higher expression level of HSP70mRNA were found in SPD1 group. These results implied SBM was more likely to induce stress reaction in shrimp than FSBM, which were closely related to the antigen protein in SBM.

Fermented Soybean Meal Increases Lactic Acid Bacteria in Gut Microbiota of Atlantic Salmon (Salmo salar)

The main goal of the present study was to address the effect of feeding fermented soybean meal-based diet to Atlantic salmon on gut microbiota. Further, expression of genes of interest, including cathelicidin antimicrobial peptide (cath), mucin 2 (muc2), aquaporin (aqp8ab), and proliferating cell nuclear antigen (pcna), in proximal intestine of fish fed either experimental diet was analyzed. Three experimental diets, including a control fishmeal (30% FM), soybean meal (30% SBM), or fermented soybean meal diet (30% FSBM) were randomly assigned to triplicate tanks during a 50-day trial. The PCR-TTGE showed microbiota composition was influenced by experimental diets. Bands corresponding to genus Lactobacillus and Pediococcus were characteristic in fish fed the FSBM-based diet. On the other hand, bands corresponding to Isoptericola, Cellulomonas, and Clostridium sensu stricto were only observed in fish FM-based diet, while Acinetobacter and Altererythrobacter were detected in fish fed SBM-based diet. The expression of muc2 and aqp8ab were significantly greater in fish fed the FSBM-based diet compared with the control group. Our results suggest feeding FSBM to Atlantic salmon may (1) boost health and growth physiology in fish by promoting intestinal lactic acid bacteria growth, having a prebiotic-like effect, (2) promote proximal intestine health by increasing mucin production, and (3) boost intestinal trans-cellular uptake of water. Further research to better understands the effects of bioactive compounds derived from the fermentation process of plant feedstuff on gut microbiota and the effects on health and growth in fish is required.

Effects of soybean meal fermented by L. plantarum, B. subtilis and S. cerevisieae on growth, immune function and intestinal morphology in weaned piglets

BACKGROUND

The present study compared the effects of soybean meal fermented by three different probiotics organisms with non-fermented soybean meal on growth performance, serum parameters, immune chemistry and intestinal morphology in weaned piglets.

METHODS

One hundred and forty-four 35-day old crossbred (Duroc × Landrace × Yorkshire) piglets were randomly allocated into four different dietary treatments (n = 36 per group) containing 0, 5, 10 and 15% fermented soybean meal.

RESULTS

The piglets fed fermented soybean meal showed an increase (p < 0.05) in average daily weight gain and a reduction in feed consumption (p < 0.05).The piglets fed 10 and 15% fermented soybean meal showed the greatest growth improvement with higher levels of serum alkaline phosphatase and total serum proteins. Serum urea nitrogen in the experimental group was significantly lower than control whereas serum IgG, IgM and IgA levels were all significantly higher. Moreover, villus height in the duodenum, jejunum, and ileum was significantly higher (p < 0.05) and the crypt depth was significantly lower (p < 0.05). The levels of the autophagy factor LC3B in piglets showed a downward trend in the jejunum and ileum compared to control.

CONCLUSIONS

Fermented soybean meal could significantly improve the growth, immune function and intestinal health in weaned piglets, and the best effective benefits showed in 10% FSBM group.

Isolation and characterization of antimicrobial peptides derived from Bacillus subtilis E20-fermented soybean meal and its use for preventing Vibrio infection in shrimp aquaculture

Bacillus subtilis E20-fermented soybean meal (FSBM) was found to produce antimicrobial peptides (AMPs) with great antimicrobial activity against Vibrio alginolyticus (VA) and V. parahaemolyticus (VP). Three AMPs were purified with a 5 kDa ultrafiltration, Sephadex G-15 column and reverse-phase high-performance liquid chromatography (RP-HPLC). The FSB-AMP, HTSKALLDMLKRLGK, identified by an RP-nano-ultrapure liquid chromatography (UPLC) electrospray ionization (ESI)-tandem mass spectroscopic (MS/MS) analysis exhibited the highest bactericidal activity against VA and VP compared to the others. The antimicrobial activity assessment indicated that FSB-AMP inhibited the growth of VA and VP with minimal inhibitory concentrations of 72.5 and 72.5 μM. Alterations in the morphology of VA were observed by scanning electronic microscopy, and membrane disruption of VA and VP was confirmed by fluorescent microscopy with propidium iodide staining. The FSB-AMP was then incorporated into the diet of white shrimp, Litopenaeus vannamei, and a protective effect in shrimp against VP infection was recorded as well as for shrimp fed a diet containing 15% fish meal replaced by B. subtilis E20-FSBM. Results demonstrated that B. subtilis E20-FSBM could be a biofunctional ingredient to prevent vibriosis in shrimp aquaculture.

Growth, enzymatic glutathione peroxidase activity and biochemical status of juvenile barramundi (Lates calcarifer) fed dietary fermented soybean meal and organic selenium

Solvent-extracted soybean meal (SBM) was fermented using baker's yeast Saccharomyces cerevisae at 30 °C for 5 days. Four isonitrogenous and isocaloric diets containing 75% SBM protein, either fermented or non-fermented (SBM and FSBM), and supplemented or not with organic Se (OS) (SBMOS and FSBMOS), were fed to triplicate groups of juvenile barramundi (Lates calcarifer) (initial weight of 5 g) for 75 days. A fishmeal (FM)-based diet formulated for juvenile barramundi was used as a reference diet. The growth of fish was significantly affected by either the interaction of SBM type or by the OS level. In fish fed diets supplemented with OS (SBMOS and FSBMOS), final weight (FW), specific growth rate (SGR) and weight gain (WG) were higher in fish fed the fermented SBM (FSBMOS) than in those fed the non-fermented SBM (SBMOS). The apparent digestibility coefficient (ADC) of protein was higher in the fish fed the fermented SBM, either supplemented or unsupplemented with OS. However, there were no significant differences in the ADC of dry matter (DM) and lipids among the tested diets and in comparison to the reference diet. The haematocrit and leucocrit of fish fed the FSBMOS diet were lower than those of fish fed the FM diet. Furthermore, glutathione peroxidase (GPx) activity was significantly influenced by OS supplementation in the experimental diets; GPx activity was greater in the fish fed diets supplemented with OS. Creatinine kinase (CK) of all groups of fish was higher than the CK of those fed the reference diet. These results suggest that with a proper nutritional level, OS supplementation may act as an important factor in enzymatic GPx activity and in the haematology and blood biochemistry status of juvenile barramundi fed fermented SBM-based diets, encouraging improvement of the overall growth performance.

Fermented soybean meal improves the growth performance, nutrient digestibility, and microbial flora in piglets

In order to increase nutritive values of soybean meal (SBM), 3 species of microbes were used to ferment SBM. Through a 3 × 3 orthogonal design and parameter measurements of soybean peptide and anti-nutritional factor contents in the fermented soybean meal (FSBM), it was estimated that the best microbial proportion of Bacillus subtilis, Hansenula anomala and Lactobacillus casei was 2:1:2 for SBM fermentation (P < 0.05). The further piglet feeding experiment showed that 10% FSBM substitute for SBM had no significant effect on growth performance of suckling piglets (d 7-28) (P > 0.05). However, newly-weaned piglets (d 28-38) fed 10% FSBM and different levels of plasma protein obtained higher average daily gain (ADG) and feed conversion ratio (FCR), compared with those without FSBM but with 6% plasma protein (P < 0.05). Piglets (d 38-68) fed diets supplemented with FSBM and soybean protein concentrate (SBPC) at 3.75% and 7.5% respectively increased nutrient digestibility, fecal enzyme activity and lactic acid bacteria counts, and decreased fecal Escherichia coli counts (P < 0.05), compared with the control. These data indicated that FSBM had positive effects on nutrient digestibility and fecal microflora for piglets.

An evaluation of replacing fish meal with fermented soybean meal in the diet of Macrobrachium nipponense: Growth, nonspecific immunity, and resistance to Aeromonas hydrophila

Partial or complete replacement of fish meal (FM) with fermented soybean meal (FSM) was examined in Macrobrachium nipponense over an 8-week growth trial. Growth and immune characteristics were evaluated. Fermented soybean meal replaced 0 (FM, control), 25% (R25), 50% (R50), 75% (R75), or 100% of the FM (R100) in five isocaloric and isonitrogenous diets. Each diet was fed to juvenile prawns (mean weight, 0.103 ± 0.0009 g) twice daily to apparent satiation in five replicates. Weight gain and specific growth rate of M. nipponense were significantly higher in prawns fed the R25 diet than that of prawns fed the FM diet. No significant differences were observed among the other treatments. Total hemocyte count and hemolymph phagocytic activity decreased as the proportion of FSM increased. Total antioxidant activity competence and malondialdehyde level in the hepatopancreas were highest in prawns fed the R100 diet. mRNA levels of the antioxidant genes Cu-Zn superoxide dismutase and catalase, heat shock cognate protein 70, and heat shock protein 90 were significantly differentially regulated in the prawn hepatopancreas. In addition, percent mortality increased after challenge with live Aeromonas hydrophila. Percent mortality of prawns fed the R100 diet was significantly higher than that of prawns fed the FM and R25 diets. These findings demonstrate that (1) M. nipponense growth performance was not affected by including a high proportion of FSM in the diet, and the best growth performance was obtained when 25% of the FM was replaced with FSM; (2) nonspecific immunity was impaired when all of the FM was replaced with FSM.

Effect of different soybean meal type on ileal digestibility of amino acid in weaning pigs

An experiment was conducted to evaluate apparent (AID) and standardized (SID) ileal digestibilities of crude protein (CP) and amino acids (AA) with 6 soybean products in weaning pigs. A total of 14 weaning barrows with an initial body weight of 6.54 ± 0.34 kg were fitted with T-cannula at the distal ileum and allotted to 7 diets containing various soybean products. The soybean products used in the experiment were conventional soybean meal (CSBM), SBM fermented by Aspergillus oryzae GB-107 (FSBMA), SBM fermented by Bacillus subtilis PP6 (FSBMB), UV sterilized SBM fermented by Bacillus subtilis PP6 (UVFSBMB), SBM containing Bacillus subtilis PP6 (PSBM), and soy protein concentrate (SPC). Six corn-based diets were used and each of soybean products was added. All diets contained 5.0 g/kg of chromic oxide as an indigestible indicator and an N-free diet was used to measure basal endogenous losses of CP and AAs. Ileal CP digestibility did not differ by different soybean products. However, SIDs of Ile, Phe and Val were improved in pigs fed the FSBMB, UVFSBMB and SPC diets and the pigs fed the FSBMA diet showed higher SIDs of Phe and Val compared with those fed the CSBM diet (P < 0.05). The FSBMB diet had higher SIDs in most AAs compared with the FSBMA diet (P < 0.05), and higher SIDs of Lys, Ala, Pro, Ser, and Tyr compared with PSBM diet (P < 0.05). However, there was no response of UV-sterilization on the FSBMB in the SIDs of AAs. These results suggest that SIDs of AAs could be improved by the supplementation of fermented soybean products in the diet for weaning pigs but fermentation with Bacillus subtilis is more efficient in improving ileal AA digestibility than that with Aspergillus oryzae. Furthermore, probiotics supplementation in the CSBM and UV-sterilization of the FSBMB had no effects on chemical composition and ileal AA digestibility.