Advances in research on solid-state fermented feed and its utilization: The pioneer of private customization for intestinal microorganisms

Synthesis and characterisation of K2CO3-activated carbon produced from distilled spent grains for the adsorption of CO2

Activated carbon was prepared from distilled spent grains (DSG) using K2CO3 activation and chitosan modification. The effects of activator dosage, activation temperature, and the incorporation of chitosan as a nitrogen source on the adsorption performance were studied in this paper. The activated carbons were characterised by scanning electron microscopy, X-ray photoelectron spectroscopy, and nitrogen and carbon dioxide gas adsorption. Under the optimal conditions, the BET-specific surface area, total pore volume, and microporous volume of the activated carbon were as high as 1142 m2/g, 0.62 cm3/g, and 0.40 cm3/g, respectively. Chitosan was used as the nitrogen source, and surface modification was carried out concurrently with the K2CO3 activation process. The results revealed a carbon dioxide adsorption capacity of 5.2 mmol/g at 273.15 K and 1 bar without a nitrogen source, which increased to 5.76 mmol/g after chitosan modification. The isosteric heat of adsorption of CO2 all exceed 20 kJ/mol, hinting at the coexistence of both physisorption and chemisorption. The adsorption behaviour of the DSG-based activated carbon can be well-described by the Freundlich model.

Impact of fermented feed of soybean hulls and rapeseed cake on immunity, antioxidant capacity, and gut microbiota in Chahua chicken

The present study investigated the effects of replacing part of the basal diet with 2-stage fermented feed (FF) (soybean hulls:rapeseed cake (2:1, m/m)) on the growth performance, immunity, antioxidant capacity, and intestinal health of Chahua chicken. A total of 160 Chahua chickens were randomly divided into 4 groups to receive a control diet or diet with 5%, 10%, or 15% of the basal diet replaced by FF, respectively for 56 d. The results showed that FF significantly improved the average daily gain (ADG) and average daily feed intake (ADFI) of Chahua chickens (P < 0.05). Furthermore, the serum immunoglobulin (Ig) A, glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) in Chahua chicken receiving the diet added with 15% FF significantly increased (P < 0.05). Chahua chicken in both the 10% and 15% groups showed increased serum IgG and IgM and decreased malondialdehyde. Serum interleukin-2 and interferon-gamma significantly increased in all FF groups. Compared with the CON group, higher ileal villus height (VH) was found in the 10% FF group. Treatment with FF significantly increased the ileal villus height/crypt depth (VH/CD) ratio, jejunal VH, and jejunal VH/CD ratio while reducing ileal and jejunal CD. The modified gut microbiota composition was observed in the Chahua chicken fed a diet containing FF, in particular, with the increased abundance of Faecalibacterium and Lactobacillus. The abundance of Lactobacillus significantly increased in the 10% and 15% FF groups (all P < 0.05). Correlation analysis revealed a positive correlation between Lactobacillus and VH (R = 0.38, P = 0.10, Figure 3B), AH/CD ratio (R = 0.63, P = 0.003), and a negative correlation with CD (R = -0.72, P = 0.001). These results indicate that FF improves immunity, antioxidant capacity, and intestinal health and consequently enhances growth performance in Chahua chicken.

Mechanism of action, benefits, and research gap in fermented soybean meal utilization as a high-quality protein source for livestock and poultry

Animal nutritionists have incessantly worked towards providing livestock with high-quality plant protein feed resources. Soybean meal (SBM) has been an essential and predominantly adopted vegetable protein source in livestock feeding for a long time; however, several SBM antinutrients could potentially impair the animal's performance and growth, limiting its use. Several processing methods have been employed to remove SBM antinutrients, including fermentation with fungal or bacterial microorganisms. According to the literature, fermentation, a traditional food processing method, could improve SBM's nutritional and functional properties, making it more suitable and beneficial to livestock. The current interest in health-promoting functional feed, which can enhance the growth of animals, improve their immune system, and promote physiological benefits more than conventional feed, coupled with the ban on the use of antimicrobial growth promoters, has caused a renewed interest in the use of fermented SBM (FSBM) in livestock diets. This review details the mechanism of SBM fermentation and its impacts on animal health and discusses the recent trend in the application and emerging advantages to livestock while shedding light on the research gap that needs to be critically addressed in future studies. FSBM appears to be a multifunctional high-quality plant protein source for animals. Besides removing soybean antinutrients, beneficial bioactive peptides and digestive enzymes are produced during fermentation, providing probiotics, antioxidants, and immunomodulatory effects. Critical aspects regarding FSBM feeding to animals remain uncharted, such as the duration of fermentation, the influence of feeding on digestive tissue development, choice of microbial strain, and possible environmental impact.

Effects of Probiotic-Fermented Feed on the Growth Profile, Immune Functions, and Intestinal Microbiota of Bamei Piglets

Purebred Bamei piglets present problems, including slow growth, respiratory disease, and post-weaning stress. This study investigated the effects of Lactobacillus plantarum QP28-1- and Bacillus subtilis QB8-fermented feed supplementation on the growth performance, immunity, and intestinal microflora of Bamei piglets from Qinghai, China. A total of 48 purebred Bamei piglets (25 days; 6.8 ± 0.97 kg) were divided into the following four groups for a 28-day diet experiment: basal feed (CK); diet containing 10% Lactobacillus plantarum-fermented feed (L); diet containing 10% Bacillus subtilis-fermented feed (B); and diet containing a mixture of 5% Lactobacillus plantarum + 5% Bacillus subtilis-fermented feed (H). The daily weight gain and daily food intake of group H increased (p < 0.05), and the feed/weight gain ratios of the groups fed with fermented feed decreased more than that of the CK group. The levels of three immune factors, namely immunoglobulin (Ig)M, IgG, and interferon-γ, were higher (p < 0.05), whereas those of tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 were lower (p < 0.05) in the fermented feed groups than in the CK group. Total protein was higher (p < 0.05), while urea nitrogen, total cholesterol and triglycerides were lower (p < 0.05) in the mixed-fermented feed group than in the CK group. Analysis of the gut microbiota showed that the addition of fermented feed increased the α-diversity of the gut microbiota, increasing the abundances of probiotics including Lactobacillus, Muribaculaceae, Ruminococcaceae, Prevotellaceae, and Rikenellaceae. Additionally, correlation analysis demonstrated that several of these probiotic bacteria were closely related to serum immunity. In conclusion, fermented feed supplementation rebuilt the intestinal microbiota of Bamei piglets, thereby reducing the feed/weight ratio, improving feed intake, and enhancing immunity.

The Effects of Fermented Feed on the Growth Performance, Antioxidant Activity, Immune Function, Intestinal Digestive Enzyme Activity, Morphology, and Microflora of Yellow-Feather Chickens

This experiment was conducted to investigate the effects of fermented feed on growth performance, antioxidant activity, immune function, intestinal digestive enzyme activity, morphology, and microflora of yellow-feather chickens. A total of 240 one-day-old female yellow-feathered (Hexi dwarf) chickens were randomly divided into two treatment groups, with six replicates per group and 20 chickens per replicate. The control group (CK) received a basal diet, whereas the experimental group was fed a basal diet of +2.00% fermented feed (FJ). The trial lasted for 22 days. Compared with the CK, (1) the growth performance was not affected (p > 0.05); (2) immunoglobin a, immunoglobin g, immunoglobin m, interleukin-1β, and interleukin-6 were affected (p < 0.05); (3) liver superoxide dismutase, glutathione peroxidase, and catalase were higher (p < 0.05); (4) trypsin activity in the duodenum and cecal Shannon index were increased (p < 0.05); (5) the relative abundance of Actinobacteriota in cecum was increased (p < 0.05); (6) the abundance of dominant microflora of Bacteroides as well as Clostridia UCG-014_norank were increased (p < 0.05). In summary, the fermented feed improved the growth performance, antioxidant activity, immune function, intestinal digestive enzyme activity, morphology, and microflora of yellow-feather chickens.

Effects of different wheat bran fermentation sources on growth performance, nutrient digestibility, serum antioxidant capacity and fecal microbiota in growing pigs

The present study aimed to evaluate the application of different wheat bran fermentation sources in growing pigs. A total of 320 pigs (43 ± 0.21 kg), were randomly allocated to 5 groups in a 21-d trial. The control group was fed a basal diet (CON) containing raw wheat bran, and the other four treatments were fed the diets in which the raw wheat bran in the basal diet was substituted with Aspergillus niger (WBA), Bacillus licheniformis (WBB), Candida utilis (WBC), and Lactobacillus plantarum (WBL) fermented wheat bran, respectively. The results showed that compared to the CON group, the crude fiber and pH values were decreased (p < 0.05), while the gross energy (GE), crude protein (CP), and lactic acid values were increased (p < 0.05) in all the wheat bran fermented by different strains. Compared with other treatments, feeding B. licheniformis fermented wheat bran had higher final weight, average daily gain, as well as lower feed-to-gain ratio. Compared with CON group, pigs fed with fermented wheat bran diets had higher dry matter, CP, and GE availability, serum total protein, albumin and superoxide dismutase levels, and fecal Lactobacillus counts, as well as lower malondialdehyde level and fecal Escherichia coli count. Collectively, our findings suggested that feeding fermented wheat bran, especially B. licheniformis fermented wheat bran, showed beneficial effects on the growth performance, nutrient digestibility, serum antioxidant capacity, and the gut microbiota structure of growing pigs.

Effects of fermented feed on growth performance, serum biochemical indexes, antioxidant capacity, and intestinal health of lion-head goslings

Introduction

The aim of this study was to evaluate the effects of fermented feed on growth performance, antioxidant indexes and intestinal health in lion-head goslings.

Methods

288 male lion-head goslings (one-day-old) were randomly divided into four groups (6 replicates per group, 12 samples per replicate): control group (basal diet) and fermented feed (FF) groups (basal diet supplemented with 2.5, 5.0 and 7.5% FF, respectively). The experimental period lasted 28 days.

Results

The results showed that 5.0 and 7.5% FF groups decreased feed conversion rate (FCR) when compared with the control group (p < 0.05). The 5.0% FF group reduced the activity of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) in serum; while the 7.5% FF group decreased the concentration of total cholesterol (TC), ALP and LDH activity (p < 0.05). Furthermore, the 7.5% FF group significantly increased total antioxidant capacity (T-AOC) in serum (p < 0.05); 2.5% and 5.0% FF groups significantly increased glutathione peroxidase (GSH-Px) in serum (p < 0.05); all FF groups increased the activity of superoxide dismutase (T-SOD) in serum (p < 0.05). For intestinal health, the villous height and villi/crypt ratio in jejunum were increased in all FF groups, but crypt depth was decreased (p < 0.05); The 5.0% FF groups enhanced T-AOC activity in jejunum (p < 0.05); The 2.5% and 5.0% FF groups enhanced GSH-Px activity (p < 0.05) in jejunum; All FF groups reduced malondialdehyde (MDA) level in jejunum (p < 0.05). LEfSe analysis showed that the cecum microbiota was significantly dominant in the 2.5% FF group compared to the control group including Firmicutes, Lactobacillales, Lactobacillus, and Prevotella; the flora that were significantly dominant in the 5.0% FF group compared to the control group included Bacteroidaceae, Bacteroides, Megamonas, and Prevotella; and the groups that were significantly dominant in the 7.5% FF group compared to the control group included Bacteroidota, Bacteroides, Bacteroidaceae, and Ruminococcaceae.

Discussion

In summary, dietary FF supplementation improved growth performance, serum biochemical parameters and antioxidant capacity of lion-head goslings, as well as improved jejunal tissue morphology and optimized intestinal flora structure. In particular, the FF addition at a dose of 7.5% was relatively more effective for lion- head goslings.

16S rDNA profiling of Loach (Misgurnus anguillicus) fed with soybean fermented powder intestinal flora in response to Lipopolysaccharide (LPS) infection

Soybean fermentation has a balancing effect on the regulation of intestinal flora. Relative research between fermented soybeans and intestinal microbiota is limited. Our aim was to explore the effects of soybean fermented fowder on lipopolysaccharide (LPS) induced intestinal microflora and corresponding functions in loach. 16S rDNA high-throughout sequencing was applied to estimate differences in the intestinal microbiota and predict genes function. Analysis of the overall of sequencing data showed that the ratio of Effective Tags in both the control group and the treatment group was greater than 80 %. Based on six major classifications involved in the phylum, class, order, family, genus, and species, we acquired the changes in the composition of intestinal microorganisms after the supplement of soybean fermented powder. These results showed that the dominant bacteria in the two groups were basically distinct at different levels. Alpha diversity analysis indicated that the microbial richness and uniformity of soybean fermented powder decreased compared to the control group. PICRUSt and Taxfun tools analysis of intestinal flora illustrated the functional genes of the six groups were mainly involved in metabolism, genetic information processing, cellular processes, environmental information processing, and human diseases at the level 1. These data clearly demonstrated the effect of soybean fermented powder on the gut microbiome. Not only that, it provides new ideas and insights for achieving high-quality utilization of soybean fermented powder. The potential mechanisms of soybean fermented powder to alter gut flora and intestinal microbiome function can further be explored.

Aquafeed fermentation improves dietary nutritional quality and benefits feeding behavior, meat flavor, and intestinal microbiota of Chinese mitten crab (Eriocheir sinensis)

Normally, proper fermentation can be an efficient and widely used method to improve feed quality in animal rearing; however, the studies on crustaceans, especially Eriocheir sinensis, remain limited. This study aimed to investigate whether feed fermentation could meliorate dietary nutritional value and benefit E. sinensis rearing. First, non-fermented feed (NFD) and fermented feed (FD) were produced and assessed, respectively. Then, the "Y" maze feed choice behavior test (180 times; 30 times, 6 rounds) was conducted to assess the attractiveness of these 2 feeds for crabs. Finally, a total of 80 crabs (44.10 ± 0.80 g) were randomly assigned into 2 groups with 4 replicates, and fed the experimental diets for 8 weeks to evaluate the effects of each feed on growth, antioxidant capacity, meat flavor, and intestinal microbiota. In this study, FD showed higher levels of crude protein (P < 0.01), soluble protein (P < 0.01), amino acids (P < 0.05), lactic acid (P < 0.001), and lower levels of crude fiber (P < 0.05) and antinutritional factors (agglutinin, trypsin inhibitor, glycinin, and β-conglycinin) (P < 0.001) than NFD. Additionally, FD was more attractive to crabs than NFD (P < 0.01) and it stimulated the appetite of crabs more than NFD (P < 0.05). The growth performance, feed efficiency, and digestive enzyme activity of FD-fed crabs were significantly higher than those of NFD-fed crabs (P < 0.05). The electronic sensory measurements and free amino acid profiles revealed that the FD diet had positive impacts on the meat flavor of crabs, particularly in "sweet" and "umami" tastes. Moreover, the antioxidant capacity of FD-fed crabs was significantly higher than that of NFD-fed crabs (P < 0.05). Fermented feed also affected the diversity and composition of intestinal microflora. The functional prediction of microbial communities showed that crabs fed FD had a better microecological environment in the intestine. In conclusion, the fermentation of aquafeed could be an effective approach to enhance feed quality and therefore benefit E. sinensis rearing.

Solid-State Fermentation as Green Technology to Improve the Use of Plant Feedstuffs as Ingredients in Diets for European Sea Bass (Dicentrarchus labrax) Juveniles

This study aimed to evaluate the utilization by juvenile European sea bass of a SSFed PF mixture with Aspergillus niger CECT 2088. A 22-day digestibility and a 50-day growth trial were performed testing four diets, including 20 or 40% of an unfermented or SSFed PF mixture (rapeseed, soybean, rice bran, and sunflower seed meals, 25% each). SSF of the PF added cellulase and β-glucosidase activity to the diets. Mycotoxin contamination was not detected in any of the experimental diets except for residual levels of zearalenone and deoxynivalenol (100 and 600 times lower than that established by the European Commission Recommendation-2006/576/EC). In diets including 20% PF, SSF did not affect growth but increased apparent digestibility coefficients of protein and energy, feed efficiency, and protein efficiency ratio. On the contrary, in diets including 40% PF, SSF decreased growth performance, feed intake, feed and protein efficiency, and diet digestibility. SSF decreased the intestinal amylase activity in the 40% SSFed diet, while total alkaline proteases decreased in the 20% and 40% SSFed diets. Hepatic amino acid catabolic enzyme activity was not modulated by SSF, and plasma total protein, cholesterol, and triglyceride levels were similar among dietary treatments. In conclusion, dietary inclusion of moderate levels of the SSFed PF, up to 20%, improves the overall feed utilization efficiency without negatively impacting European sea bass growth performance. The replacement of PF with the SSFed PF mixture may contribute to reducing the environmental footprint of aquaculture production.

Research advances in probiotic fermentation of Chinese herbal medicines

Chinese herbal medicines (CHM) have been used to cure diseases for thousands of years. However, the bioactive ingredients of CHM are complex, and some CHM natural products cannot be directly absorbed by humans and animals. Moreover, the contents of most bioactive ingredients in CHM are low, and some natural products are toxic to humans and animals. Fermentation of CHM could enhance CHM bioactivities and decrease the potential toxicities. The compositions and functions of the microorganisms play essential roles in CHM fermentation, which can affect the fermentation metabolites and pharmaceutical activities of the final fermentation products. During CHM fermentation, probiotics not only increase the contents of bioactive natural products, but also are beneficial for the host gut microbiota and immune system. This review summarizes the advantages of fermentation of CHM using probiotics, fermentation techniques, probiotic strains, and future development for CHM fermentation. Cutting-edge microbiome and synthetic biology tools would harness microbial cell factories to produce large amounts of bioactive natural products derived from CHM with low-cost, which would help speed up modern CHM biomanufacturing.

Effects of fermented feed on growth performance, immune organ indices, serum biochemical parameters, cecal odorous compound production and the microbiota community in broilers

The aim of this study was to explore the effects of dietary fermented feed addition on growth performance, immune organ indices, serum biochemical parameters, cecal odorous compound production, and the bacterial community in broilers. A total of 480 broiler chicks (1-day-old) were randomly assigned to 6 groups, including a basal diet (control group), a basal diet supplemented with 10, 15, 20, and 25% dried fermented feed, and 10% wet fermented feed. Each group contained 8 replicates of 10 chicks each. The results showed that fermentation increased (P < 0.05) the total acid level and the number of Lactobacillus, Yeast, and Bacillus. The 15% dried fermented feed group had an increased (P < 0.05) body weight (BW) than the control, while the 25% dried fermented feed group had the lowest (P < 0.05) BW on 42 d. Compared to the control group, the feed intake (FI) was increased (P < 0.05) in the 10, 15% dried and 10% wet fermented feed groups from 22 to 42 d and from 1 to 42 d. No significant difference (P > 0.05) was observed in feed conversion ratio (FCR) among all groups. Supplementation with fermented feed increased (P < 0.05) the bursa of Fabricius index but not (P > 0.05) the thymus and spleen indices. Compared with the control, the broilers fed fermented feed had increased (P < 0.05) serum total protein, albumin, globulin, IgA, IgG, IgM, lysozyme, complement 3, and complement 4 levels. The cecal concentrations of acetic acid, propionic acid, butyric acid, and lactic acid were increased and the pH values were decreased in the fermented feed groups (P < 0.05). Among the groups, the 15% dried fermented feed group showed the lowest concentrations of skatole and indole in the cecum (P < 0.05). The composition of the cecal microbiota was characterized, in which an increased abundance of Ruminococcaceae, Lactobacillaceae, and unclassified Clostridiales and a decreased abundance of Rikenellaceae, Lachnospiraceae, and Bacteroidaceae were found in the fermented feed groups. Taken together, dietary fermented feed supplementation can improve growth performance, immune organ development, and capacity and decrease cecal odorous compound production, which may be related to the regulation of microbial composition.

Bioconversion of food waste to crayfish feed using solid-state fermentation with yeast

In order to realize the value-added utilization of food waste (FW), the preparation of crayfish (Procambarus clarkii) feed by yeast fermentation was investigated. Firstly, the suitable fermentation condition was obtained through a single factor experiment as follows: the initial moisture of the FW was adjusted to 60% with bran and inoculated with a 2% yeast mixture (Saccharomyces cerevisiae, Candida utilis, and Yarrowia lipolytica, 3:2:1) followed by aerobic solid-state fermentation for 7 days. The crude protein and acid-soluble protein contents in the fermented feed were 25.14% and 5.16%, which were increased by 8% and 140.67%, respectively. The crude fat content was 0.74%, decreased by 68.29%. The content of antioxidant glutathione (571.78 μg/g) increased 63.33%, and the activities of protease and amylase increased nearly 9 and 3 times, respectively. The maximum degradation rates of aflatoxin B1, zearalenone, and deoxynivalenol were 63.83%, 77.52%, and 80.16%, respectively. The fermented feeds were evaluated by substituting (0%, 10%, 30%, 50%, and 100%) commercial diet for crayfish (30-day culture period). When the replacement proportion was 30%, the weight gain of crayfish reached 44.87% (initial body weight 13.98 ± 0.41 g), which was significantly increased by 10.25% compared with the control (p = 0.0005). In addition, the lysozyme and SOD enzyme activities in crayfish hepatopancreas were also increased significantly. Our findings suggest that yeast-fermented feed from FW can replace 30% of crayfish's conventional diet, which may improve crayfish's antioxidant capacity and enhance non-specific immunity by providing molecules such as glutathione.

Isolation of a Novel Anti-Diabetic α-Glucosidase Oligo-Peptide Inhibitor from Fermented Rice Bran

At present, the incidence rate of diabetes is increasing gradually, and inhibiting α-glucosidase is one of the effective methods used to control blood sugar. This study identified new peptides from rice bran fermentation broth and evaluated their inhibitory activity and mechanism against α-glucosidase. Rice bran was fermented with Bacillus subtilis MK15 and the polypeptides of <3 kDa were isolated by ultrafiltration and chromatographic column, and were then subjected to LC-MS/MS mass spectrometry analysis. The results revealed that the oligopeptide GLLGY showed the greatest inhibitory activity in vitro. Docking studies with GLLGY on human α-glucosidase (PDB ID 5NN8) suggested a binding energy of −7.1 kcal/mol. GLLGY acts as a non-competitive inhibitor and forms five hydrogen bonds with Asp282, Ser523, Asp616, and His674 of α-glucosidase. Moreover, it retained its inhibitory activity even in a simulated digestion environment in vitro. The oligopeptide GLLGY could be developed into a potential anti-diabetic agent.

Transformation Capability Optimization and Product Application Potential of Proteatia brevitarsis (Coleoptera: Cetoniidae) Larvae on Cotton Stalks

Cotton stalks (CS) are a potential agricultural biomass resource. We investigated the use of CS as a feed for Proteatia brevitarsis Lewis larvae and the resulting frass (larvae dung-sand) as a fertilizer. Based on a three-factor experiment (decomposition inoculant, fermentation duration, and cattle manure ratio), the optimal parameters for the transformation of CS using P. brevitarsis larvae were determined as 40-50% of cattle manure, the use of VT inoculant and a fermentation duration of 25-30 days. Regarding the products of the transformation, the protein content of the larval body was as high as 52.49%, and the fat content was 11.7%, which is a suitable-quality insect protein source. The organic matter content of larvae dung-sand was 54.8%, and the content of total nitrogen, phosphorus, and potassium (TNPK) was 9.04%, which is twice more than that of the organic fertilizer standard (NY525-2021, Beijing, China, TNPK ≥ 4.0%), and larvae dung-sand has the potential of fertilizer application. Therefore, CS as a feed and fertilizer based on the transformation of P. brevitarsis larvae is feasible, and it is a highly efficient way to promote the utilization of both CS and cattle manure.

The Existing Recovery Approaches of the Huangjiu Lees and the Future Prospects: A Mini Review

Huangjiu lees (HL) is a byproduct in Chinese Huangjiu production with various nutrient and biological functional components. Without efficient treatment, it could cause environmental issues and bioresource wasting. Existing dominant recovery approaches focus on large-scale disposal, but they ignore the application of high-value components. This study discusses the advantages and limitations of existing resourcing approaches, such as feed, food and biogas biological production, considering the efficiency and value of HL resourcing. The extraction of functional components as a suggestion for HL cascade utilization is pointed out. This study is expected to promote the application of HL resourcing.

Effects of Fermenting the Plant Fraction of a Complete Feed on the Growth Performance, Nutrient Utilization, Antioxidant Functions, Meat Quality, and Intestinal Microbiota of Broilers

Simple Summary

Fermented feed is an effective way to replace antibiotics in poultry. The purpose of this study was to explore the effects of different levels of fermented feeds on growth performance, nutrient utilization, antioxidant function, meat quality, and intestinal microorganisms of broilers. The current research results showed that adding 10% fermented feed significantly improved the growth performance in 1–21 days, and adding 5% fermented feed significantly improved the growth performance in 1–42 days. Adding 15% fermented feed significantly improved the metabolic rate of the birds in 19–21 days and significantly increased the monounsaturated fatty acid concentration in the chickens. Adding fermented feed significantly reduced the cholesterol content in the chickens. In a word, adding 10% fermented feed significantly reduced the feed conversion ratio in 1–21 days and adding 5% fermented feed significantly improved the average daily gain and the average daily feed intake in 1–42 days. In addition, consuming fermented feed improved the meat quality of broilers.

Abstract

We investigated the effects of fermenting the plant fraction of a solid complete feed (FPFF) on the growth performance, nutrient utilization, meat quality, antioxidant status, and intestinal microbiota of broiler chickens. The plant-based fraction of the complete feed was fermented using Lactobacillus and Bacillus subtilis. A total of 240, 1-day-old male Arbor Acres broilers were randomly allocated into four treatment groups, each comprised of six replicates. The groups were fed a corn–soybean meal-based diet (basic diet) or the same diet supplemented with 5%, 10%, or 15% FPFF for 6 weeks. As results, adding 10% fermented feed significantly improved the growth performance in 1–21 days, and adding 5% fermented feed significantly improved the growth performance in 1–42 days. Adding 15% fermented feed significantly improved the metabolic rate of the birds in 19–21 days and significantly increased the monounsaturated fatty acid concentration in the chickens. Adding fermented feed significantly reduced the cholesterol content in the chickens. In conclusion, adding 10% fermented feed significantly reduced the feed conversion ratio in 1–21 days and adding 5% fermented feed significantly improved the average daily gain and the average daily feed intake in 1–42 days. In addition, consuming fermented feed improved the meat quality of broilers.

Fermented grape seed meal promotes broiler growth and reduces abdominal fat deposition through intestinal microorganisms

The fermentation of grape seed meal, a non-conventional feed resource, improves its conventional nutritional composition, promotes the growth and development of livestock and fat metabolism by influencing the structure and diversity of intestinal bacteria. In this study, the nutritional components of Fermented grape seed meal (FGSM) and their effects on the growth performance, carcass quality, serum biochemistry, and intestinal bacteria of yellow feather broilers were investigated. A total of 240 male 14-day-old yellow-feathered broilers were randomly selected and divided into four groups, with three replicates of 20 chickens each. Animals were fed diets containing 0% (Group I), 2% (Group II), 4% (Group III), or 6% (Group IV) FGSM until they were 56 days old. The results showed that Acid soluble protein (ASP) and Crude protein (CP) contents increased, Acid detergent fiber (ADF) and Neutral detergent fiber (NDF) contents decreased, and free amino acid content increased in the FGSM group. The non-targeted metabolome identified 29 differential metabolites in FGSM, including organic acids, polyunsaturated fatty acids, and monosaccharides. During the entire trial period, Average daily gain (ADG) increased and Feed conversion ratio (FCR) decreased in response to dietary FGSM supplementation (p < 0.05). TP content in the serum increased and BUN content decreased in groups III and IV (p < 0.05). Simultaneously, the serum TG content in group III and the abdominal fat rate in group IV were significantly reduced (p < 0.05). The results of gut microbiota analysis showed that FGSM could significantly increase the Shannon and Simpson indices of broilers (35 days). Reducing the relative abundance of Bacteroidetes significantly altered cecal microbiota composition by increasing the relative abundance of Firmicutes (p < 0.05). By day 56, butyric acid content increased in the cecal samples from Group III (p < 0.05). In addition, Spearman's correlation analysis revealed a strong correlation between broiler growth performance, abdominal fat percentage, SCFAs, and gut microbes. In summary, the addition of appropriate levels of FGSM to rations improved broiler growth performance and reduced fat deposition by regulating gut microbes through differential metabolites and affecting the microbiota structure and SCFA content of the gut.

Microflora for improving the Auricularia auricula spent mushroom substrate for Protaetia brevitarsis production

Mushroom cultivation is a sustainable agricultural waste utilization method, but the lack of high-value utilization of the produced spent mushroom substrate (SMS) has hindered the development of mushroom cultivation-based circular agricultural systems. Conversion and utilization of SMS via Protaetia brevitarsis larvae (PBL) have proven to be a high-value AASMS utilization strategy. However, Auricularia auricula SMS (AASMS), which contains woodchips, is less palatable and digestible for PBL. To solve this problem, in this investigation, we screened out microflora (MF) for AASMS fermentation by comparing the fermentation performance as well as the effect on PBL feed intake, weight gain, and AASMS phytotoxic compound removal efficiency. In addition, by bacterial community analysis, the genera Luteimonas, Moheibacter, and Pseudoxanthomonas were predicted to be functional bacteria for AASMS fermentation and contribute to palatability and digestibility improvement.

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Larvae frass microflora can ferment Auricularia auricula spent mushroom substrate

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The fermentation can improve feed intake, weight gain, and phytotoxic removal efficiency

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The genera Luteimonas, Moheibacter, and Pseudoxanthomonas were functional bacteria

Signature of dissolved organic matter and microbial communities based on different oxygen levels response during distillers dried grains with solubles plus sugarcane pith co-fermentations

The objective of this study was to investigate the relationship between dissolved organic matter (DOM) and microbial communities during the co-fermentation of distillers dried grains with solubles (DDGS) and sugarcane pith at different oxygen levels. In aerobic fermentation (AF), the content of DOM decreased from 32.61 mg/g to 14.14 mg/g, and decreased from 32.61 mg/g to 30.83 mg/g in anaerobic fermentation (ANF). Phenols and alcohols were consumed first in AF, while lipids and proteins were consumed first in ANF. Degradation rates of cellulose, hemicellulose and lignin in AF (6.67%, 39.93%, 36.50%) were higher than those in ANF (0.69%, 18.36%, 9.12%). Firmicutes, Actinobacteriota and Ascomycota were the main phyla in community. Distance-based redundancy analysis showed that pH, organic matter (OM) and DOM were the main driving factors of microbial community succession.