Effect of fermented feed on the microbial population of the gastrointestinal tracts of pigs

Optimising the hygiene of a liquid feeding system to improve the quality of liquid feed for pigs

Poor feeding system hygiene may contribute to uncontrolled spontaneous fermentation in liquid pig feed and its associated undesirable effects. This study aimed to determine the effects of an intensive sanitisation programme in a grow-finisher liquid feeding system by monitoring microbiological and physico-chemical parameters of liquid feed and microbial colonisation of the feeding system surfaces. The sanitisation programme involved a combination of physical and chemical cleaning between batches of grow-finisher pigs, combined with nightly rinsing of the system with an organic acid blend. Improved hygiene of the internal surfaces of the mixing tank and feed pipeline, particularly until week 5 post-cleaning, was evidenced by reduced counts of lactic acid bacteria, total aerobes, Enterobacteriaceae, yeasts and moulds and decreased adenosine triphosphate concentrations. Enterobacteriaceae and moulds remained undetectable on pipeline surfaces for 10 weeks. Scanning electron microscopy of the feed pipelines confirmed these findings. Conversely, the impact on liquid feed microbiology was minimal and short-lived. However, acetic acid, ethanol and biogenic amine concentrations decreased in the feed post-cleaning and no gross energy losses were observed. Therefore, by controlling surface microbial communities on liquid feeding systems via implementation of the sanitisation programme developed in the current study, on-farm liquid feed quality should be improved.

Supplementation of lactobacillus-fermented rapeseed meal in broiler diet reduces Campylobacter jejuni cecal colonization and limits the l-tryptophan and l-histidine biosynthesis pathways

BACKGROUND

Campylobacter jejuni (C. jejuni), a widely distributed global foodborne pathogen, primarily linked with contaminated chicken meat, poses a significant health risk. Reducing the abundance of this pathogen in poultry meat is challenging but essential. This study assessed the impact of Lactobacillus-fermented rapeseed meal (LFRM) on broilers exposed to C. jejuni-contaminated litter, evaluating growth performance, Campylobacter levels, and metagenomic profile.

RESULTS

By day 35, the litter contamination successfully colonized broilers with Campylobacter spp., particularly C. jejuni. In the grower phase, LFRM improved (P < 0.05) body weight and daily weight gain, resulting in a 9.2% better feed conversion ratio during the pre-challenge period (the period before artificial infection; days 13-20). The LFRM also reduced the C. jejuni concentration in the ceca (P < 0.05), without altering alpha and beta diversity. However, metagenomic data analysis revealed LFRM targeted a reduction in the abundance of C. jejuni biosynthetic pathways of l-tryptophan and l-histidine and gene families associated with transcription and virulence factors while also possibly leading to selected stress-induced resistance mechanisms.

CONCLUSION

The study demonstrated that LFRM inclusion improved growth and decreased cecal Campylobacter spp. concentration and the relative abundance of pivotal C. jejuni genes. Performance benefits likely resulted from LFRM metabolites. At the molecular level, LFRM may have reduced C. jejuni colonization, likely by decreasing the abundance of energy transduction and l-histidine and l-tryptophan biosynthesis genes otherwise required for bacterial survival and increased virulence. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Effects of Lactobacillus-fermented low-protein diets on the growth performance, nitrogen excretion, fecal microbiota and metabolomic profiles of finishing pigs

This study investigated the effects of Lactobacillus-fermented low-protein diet on the growth performance, nitrogen balance, fecal microbiota, and metabolomic profiles of finishing pigs. A total of 90 finishing pigs were assigned to one of three dietary treatments including a normal protein diet (CON) as well as two experimental diets in which a low-protein diet supplemented with 0 (LP) or 1% Lactobacillus-fermented low-protein feed (FLP). In comparison with CON, the LP and FLP significantly increased average daily gain (P = 0.044), significantly decreased feed to gain ratio (P = 0.021), fecal nitrogen (P < 0.01), urine nitrogen (P < 0.01), and total nitrogen (P < 0.01), respectively. The LP group exhibited increased abundances of unclassified_f_Selenomonadaceae, Coprococcus, Faecalibacterium, and Butyricicoccus, while the abundances of Verrucomicrobiae, Verrucomicrobiales, Akkermansiaceae, and Akkermansia were enriched in the FLP group. Low-protein diet-induced metabolic changes were enriched in sesquiterpenoid and triterpenoid biosynthesis and Lactobacillus-fermented low-protein feed-induced metabolic changes were enriched in phenylpropanoid biosynthesis and arginine biosynthesis. Overall, low-protein diet and Lactobacillus-fermented low-protein diet improved the growth performance and reduce nitrogen excretion, possibly via altering the fecal microbiota and metabolites in the finishing pigs. The present study provides novel ideas regarding the application of the low-protein diet and Lactobacillus-fermented low-protein diet in swine production.

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 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.

Research Progress of Biological Feed in Beef Cattle

Biological feed is a feed product developed through bioengineering technologies such as fermentation engineering, enzyme engineering, protein engineering, and genetic engineering. It possesses functional characteristics of high nutritional value and good palatability that can improve feed utilization, replace antibiotics, enhance the health level of livestock and poultry, improve the quality of livestock products, and promote a better breeding environment. A comprehensive review is provided on the types of biological feed, their mechanism of action, fermenting strains, fermenting raw material resources, and their current status in animal production to facilitate in-depth research and development of applications.

Liquid fermented cereals with added Pediococcus acidilactici did not reduce post-weaning diarrhea in pigs - an Escherichia coli challenge study

The effect of feeding fermented liquid feed (FLF) with added Pediococcus acidilactici to weaning piglets challenged with enterotoxigenic Escherichia coli (ETEC) F4 on aspects of diarrhea, performance, immune responses, and intestinal epithelial barrier function was investigated. A total of 46 weaners (weaning at 27-30 days of age) were assigned to four treatments: (1) Non-challenged and dry feed (Non-Dry); (2) Challenged and dry feed (Ch-Dry); (3) Non-challenged and FLF (Non-Ferm); (4) Challenged and FLF (Ch-Ferm). All groups received the same feed, either dry (Non-Dry and Ch-Dry), or in liquid form (Non-Ferm and Ch-Ferm) in which the cereals with added P. acidilactici (10⁶ CFU/g cereals) had been fermented for 24 h at 30°C. On day 1 and 2 post weaning, Ch-Dry and Ch-Ferm were orally inoculated with 5 mL × 10⁹ CFU ETEC F4/mL, whereas the Non-Dry and Non-Ferm received the same amount of saline. Fecal samples and blood samples were collected through the study period. The microbial composition, concentration of microbial metabolites and nutrient composition indicated that the quality of the FLF was high. In the first week, ADFI of both non-challenged groups was significantly higher (p < 0.05) than that of the Ch-Ferm group. The two challenged groups had higher fecal levels of FaeG gene (ETEC F4 fimbriae) from day 2 to 6 post weaning (p < 0.01), and higher risk of having ETEC F4 present in feces from day 3 to 5 post weaning (p < 0.05) compared to non-challenged groups, indicating the validity of the ETEC challenge model. Generally, ADG of the two groups fed FLF were numerically higher than those fed dry feed. Neither challenge nor FLF affected diarrhea. No significant differences were measured between Ch-Ferm and Ch-Dry regarding the level of plasma haptoglobin and C-reactive protein, hematological parameters or parameters related to epithelial barrier. The data indicated a low level of infection caused by the ETEC challenge, while recovery from weaning stress could be observed. The study showed that a strategy like this can be a way of providing a high level of probiotics to pigs by allowing their proliferation during fermentation.

Effect of Fermented Rapeseed Meal in Diets for Piglets on Blood Biochemical Parameters and the Microbial Composition of the Feed and Faeces

The study assessed the influence of rapeseed meal (RSM) fermented using Bacillus subtilis 87Y on the feed microbiota, intestinal microbiota, blood biochemical parameters, and content of minerals in the blood plasma and faeces of piglets. Modulation of the microbial composition of feed containing fermented rapeseed meal (FRSM) and of the faeces of pigs consuming it was observed. There was a significant increase in the number of lactic acid bacteria (LAB) and a decrease in the total number of coliforms and Clostridium perfringens in the faeces of animals from the experimental groups. FRSM in the diet of piglets was shown to improve the mineral balance by increasing the levels of P, Ca, and Mg in the blood plasma and reducing their amount in the faeces. A beneficial effect on parameters of protein and lipid metabolism was also noted, resulting in an increase in the levels of total protein (TP) and albumins (ALB) and a reduction in triacylglycerols (TG) and low-density lipoprotein (LDL) cholesterol in the blood plasma of the piglets. The research results indicate that the presence of FRSM in the diet of weaners can be a preventive factor in intestinal dysbiosis and support the maintenance of homeostasis.

Uncovering the core principles of the gut-lung axis to enhance innate immunity in the chicken

Research in mammals has evidenced that proper colonization of the gut by a complex commensal microbial community, the gut microbiota (GM), is critical for animal health and wellbeing. It greatly contributes to the control of infectious processes through competition in the microbial environment while supporting proper immune system development and modulating defence mechanisms at distant organ sites such as the lung: a concept named ‘gut-lung axis’. While recent studies point to a role of the GM in boosting immunity and pathogen resilience also in poultry, the mechanisms underlying this role are largely unknown. In spite of this knowledge gap, GM modulation approaches are today considered as one of the most promising strategies to improve animal health and welfare in commercial poultry production, while coping with the societal demand for responsible, sustainable and profitable farming systems. The majority of pathogens causing economically important infectious diseases in poultry are targeting the respiratory and/or gastrointestinal tract. Therefore, a better understanding of the role of the GM in the development and function of the mucosal immune system is crucial for implementing measures to promote animal robustness in commercial poultry production. The importance of early gut colonization in the chicken has been overlooked or neglected in industrial poultry production systems, where chicks are hampered from acquiring a complex GM from the hen. Here we discuss the concept of strengthening mucosal immunity in the chicken through GM modulation approaches favouring immune system development and functioning along the gut-lung axis, which could be put into practice through improved farming systems, early-life GM transfer, feeding strategies and pre-/probiotics. We also provide original data from experiments with germ-free and conventional chickens demonstrating that the gut-lung axis appears to be functional in chickens. These key principles of mucosal immunity are likely to be relevant for a variety of avian diseases and are thus of far-reaching importance for the poultry sector worldwide.

Effect of fermented rapeseed meal in the mixture for growing pigs on the gastrointestinal tract, antioxidant status, and immune response

The ban on the use of zinc oxide has increased interest in probiotics, prebiotics, synbiotics and organic acids, as well as fermented components in the diet of weaned piglets. This study assessed the effect of 8% fermented rapeseed meal in weaner diets on characteristics of the gastrointestinal tract, the small intestinal microbiota, and immune and antioxidant status. The effects were determined by measuring biochemical and haematological blood parameters, levels of class G, A and M immunoglobulins and IL-6, and the antioxidant potential of the plasma. After slaughter, the gastrointestinal tract was measured, the viscosity of the digesta was determined, and microbiological tests were performed. The results showed that the fermented component reduced the viscosity of the digesta and the length of segments of the gastrointestinal tract. It caused a statistically significant increase in lactic acid bacteria and a decrease in total bacteria. The haematological and biochemical analyses of the blood confirmed the biological activity of the fermented component. Pigs from group FR had significantly higher haemoglobin levels (p = 0.001), RBC count (p = 0.015), and haematocrit (Ht) value (p < 0.001) than the control animals. A diet including 8% rapeseed meal fermented using Bacillus subtilis strain 87Y benefits gastrointestinal function by stabilizing and improving the function of the bacterial microbiota, inhibiting growth of certain pathogens, and strengthening immunity.

Fecal Microbial Changes in Response to Finishing Pigs Directly Fed With Fermented Feed

The present study investigated the effects of fermented complete feed (FCF) on fecal microbial composition during the grower-finisher period. A total of 20 pigs (Duroc × Landrace × Yorkshire, 48.74± 1.49 kg) were divided randomly into two groups: the CN group (pigs fed with a basal diet) and the FCF group (pigs fed with FCF). After a 60-day trial period, 3 pigs with middle-weight from each treatment were selected for fecal sampling and fecal microbiota analysis. The results showed that the FCF significantly increased operational taxonomic units (OUT) numbers, alpha diversity (Simpson index and Shannon index), and beta diversity, which means that FCF increased the fecal microbiota diversity. At the phylum level, the abundance of Tenericutes, Spirochaetae, Verrucomicrobia, and Cyanobacteria were changed in pigs fed with FCF; and at the genus level, the abundance of Christensenellaceae_R-7_group, Treponema_2, Ruminococcaceae_UCG-005, Prevotellaceae_UCG-003, Phascolarctobacterium, Roseburia, and Prevotella_9 were changed in pigs fed with FCF. The linear discriminant analysis effect size (LEfSe) analysis showed that Roseburia and Prevotella_9 genera were increased, while Tenericutes phyla and Streptococcus, Christensenellaceae_R-7_group, and Lactobacillus genera were decreased in the FCF group compared to the CN group. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) results predicted that the relative abundance of infectious diseases: parasitic associated genes, xenobiotics biodegradation, and metabolism-associated genes were significantly reduced in the FCF group when compared with the CN group, and the relative abundance of signal transduction associated genes, amino acid metabolism-related genes, and replication and repair associated genes were significantly higher in the FCF group when compared with the CN group. In addition, the relative abundance of transport and catabolism-associated genes, membrane transport-associated genes, and biosynthesis of other secondary metabolite-associated genes tended to be higher in the FCF group when compared with the CN group; and the relative abundance of immune diseases associated genes tended to be lower in the FCF group when compared with the CN group. In conclusion, the FCF influenced the alpha and beta diversity of the fecal microbiota of pigs.

Fermentation Characteristics of Rye and Sorghum Depending on Water:Feed Ratio

This study was conducted to determine the fermentation characteristics of rye or sorghum mixed with different ratios of water (25%, 37.5%, 50%, 62.5%, and 75% in dry matter (DM)), incubated up to 48 h. The pH of the fermented rye at a DM content of 25% after 24 h had the lowest values (3.57) compared to that at a DM content of 75% (6.42). In fermented sorghum, pH values were lower than 4 already after incubation at 25% DM for 12 h (3.93) in comparison to that at DM content 75% (6.51). The L-lactic acid concentration in the fermented rye with 25% DM content after 24 h was significantly the highest (18.7 g/kg DM), as was that of sorghum with 25% DM content after 24 h (22.2 g/kg DM). Moreover, the acetic acid level in the fermented rye with 25% DM content after 24 h was significantly the highest (3.02 g/kg DM) compared to the other DM contents of fermented rye. Also, in fermented sorghum (25% DM), the acetic acid content was significantly the greatest (1.49 g/kg DM) in comparison to the other DM contents of fermented sorghum. Overall, fermented rye and sorghum containing 25 or 37.5% DM for 24 h and 12 h for rye and sorghum, respectively are sufficient for fermentation to be optimized based on the values of pH and lactic acid content, except for acetic acid content, which may negatively affect the palatability in animals.

Use of Tannin-Containing Plants as Antimicrobials Influencing the Animal Health

The antimicrobial effects of diverse tannin-containing plants, particularly condensed tannins (CTs) produced from various plants, are the subject of this study. CT components can be determined using CT-specific procedures such the HCl-Butanol Acetone assay, Thiolysis reaction, and HPLC/MS analysis. These methods indicate CT contents, including mean degree of polymerization, the procyanidins and prodelphinidins ratio (PC/PD%), the isomers of trans- and cis-, and CT concentration. Tannin-containing plants possess antibacterial action, which can be attributed to their protein linkage technique, and tannin-type variations, particularly CTs extract and their PC/PD%. The effects of CT components on the development of Gram-positive and Gram-negative bacteria have been documented for their relative PC/PD%; this is regarded to be a key predictor of tannin characteristics in terms of antimicrobials. In conclusion, tannins, more specific CT compositions, have significant impacts on in vivo trials of animal productions and utilization of metabolites and fermentation in vitro experiments. These findings need further investigations to fully understand how CT-types act on animal feeding in terms of enhanced nutritional quality of animal diets, which may have implications for human and animal health.

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

With sustainable development of biotechnology, increasing attention has been placed on utilization of solid-state fermented feed (SFF). Solid-state fermented feed has been a candidate strategy to alleviate the contradiction between supply and demand of feed resources, ensure food hygiene safety, promoting energy conservation, and emission reduction. In production of SFF, a variety of organic acids, enzymes, vitamins, peptides, and other unknown growth factors are produced, which could affect performance of animals. Solid-state fermented feed produced by different fermentation techniques has great instability on different physiological stages of different animals, which hinders the application and standardized production of SFF. Herein, we summarize the current advances in the role of the characteristics of SFF prepared by different manufacturing technique and its research progress in animal experiments on growth performance, gastrointestinal ecology, and immune system, so as to provide references for further acquiring a relatively perfect set of SFF production and evaluation systems.

Effects of Microbial Fermented Feed on Serum Biochemical Profile, Carcass Traits, Meat Amino Acid and Fatty Acid Profile, and Gut Microbiome Composition of Finishing Pigs

Microbial fermented feed is an important part of feed industry, while little research has focused on the solid-state fermentation of complete feed. Herein, the purpose of the present study was to investigate the effects of fermented complete feed (FCF) on the growth performance, biochemical profile, carcass traits, meat proximate composition, meat amino acid and fatty acid profile, and gut microbiome composition of finishing pigs, thereby providing references for the application of FCF in animal production. Twenty Duroc × Landrace × Yorkshire pigs with an average body weight (BW) of 48.74 ± 1.49 kg were divided randomly into control group (pigs received a basal diet, CN, n = 10) and FCF group (pigs fed with FCF, n = 10). The experiment lasted for 60 days. FCF improved the growth performance, which was indicated by a significantly increased final BW, average daily gain and average daily feed intake, and a significantly decreased feed-to-gain ratio. FCF improved biochemical profile, which was indicated by a higher alkaline phosphatase, glucose, immunoglobulin G, immunoglobulin M, superoxide dismutase, and total antioxidant capacity content. Pigs that received FCF had better carcass traits and meat quality than did pigs that received basal diet, which was indicated by a higher carcass length, crude protein content, lysine content, Glu content, C18:ln9c, C18:2n6c, C20:4n6, and unsaturated fatty acid content and a lower average back-fat thickness, C18:0, and saturated fatty acids. FCF significantly reduced the relative abundances of presumably pathogenic bacteria of phylum Proteobacteria and genus Escherichia–Shigella and enhanced the relative abundances of likely beneficial bacteria of phylum Firmicutes and genus Clostridium. In summary, FCF had a certain effect on the improvement of growth performance, serum biochemical profile, carcass traits, meat proximate composition, amino acid and fatty acid profile, and gut microbiome composition of finishing pigs.

Microbial Quality of Liquid Feed for Pigs and Its Impact on the Porcine Gut Microbiome

Simple Summary

Liquid feed is produced by mixing dry feed ingredients with water, and sometimes liquid co-products from the food and beverage industry, at a defined ratio. Liquid feeding of pigs is popular, particularly in parts of northern and western Europe, and can be associated with lower feed costs, improved dry matter intake, growth rate and gut health, compared to dry feeding. However, spontaneous/uncontrolled fermentation upon mixing of feed with water or co-products can decrease the microbial and nutritional quality of the feed, resulting in poorer pig health and growth. For this reason, strategies aimed at optimising liquid feed microbial quality are frequently employed. These include: deliberate fermentation with/without the use of lactic acid bacteria starter cultures that produce lactic acid and lower the feed pH, thereby preventing growth of pathogens. Fermenting only the cereal component of the diet is preferred to whole diet fermentation to minimise loss of free amino acids from the diet during fermentation. This review examines the microbiome of liquid feed and explores how optimisation strategies impact both feed microbial quality and the gut microbiota and growth of liquid-fed pigs. It also covers cleaning and disinfection of liquid feeding systems and how this might impact liquid feed microbial quality.

Abstract

There is evidence that spontaneous fermentation frequently occurs in liquid pig feed that is intended to be delivered as fresh liquid feed, often with a resultant deterioration in the microbial and nutritional quality of the feed, which can negatively affect pig health and growth. Strategies including controlled fermentation with microbial inoculants, pre-fermentation or soaking of the cereal fraction of the diet, enzyme supplementation and dietary acidification have been employed to inhibit pathogens and prevent deterioration of feed nutritional quality, with promising results obtained in many cases. This review evaluates the impact of these strategies on the microbial quality of liquid feed and discusses how they can be further improved. It also investigates if/how these strategies impact the pig gut microbiota and growth performance of liquid-fed pigs. Finally, we review liquid feed system sanitisation practices, which are highly variable from farm to farm and discuss the impact of these practices and whether they are beneficial or detrimental to liquid feed microbial quality. Overall, we provide a comprehensive review of the current state of knowledge on liquid feed for pigs, focusing on factors affecting microbial quality and strategies for its optimisation, as well as its impact on the pig gut microbiome.

Dietary fermented rapeseed or/and soybean meal additives on performance and intestinal health of piglets

The aim of the study was to assess the effect of fermented dried soybean (FSBM) and/or fermented rapeseed meal (FRSM) in diets for weaned piglets on production results, nutrient digestibility, gastrointestinal tract histology, and the composition of the gut microbiota. Piglets in the control group received standard diets with soybean meal. Animals in all experimental groups received diets in which a portion of the soybean meal was replaced: in group FR-8% FRSM; in group FR/FS-6% FRSM and 2% FSBM; in group FS/FR-2% FRSM and 6% FSBM and in group FS-8% FSBM. The use of 8% FRSM or 6% FRSM and 2% FSBM in the piglet diets had a positive effect on average daily gains. Piglets from the FR and FR/FS groups had the highest feed conversion rate. Group FS/FR and FS piglets had significantly lower mortality and lower incidence of diarrhoea. Piglets fed a diet with the fermented components, in particular with 8% FRSM or 6% FRSM and 2% FSBM, exhibited a positive effect on the microbiological composition and histology of intestines, which resulted in improved nutrient digestibility coefficients (ATTD and AID).

Fermented Diet Liquid Feeding Improves Growth Performance and Intestinal Function of Pigs

Simple Summary

The present study indicated that fermented liquid feeding improved the growth performance of pigs, which might be associated with gastrointestinal hormone and intestinal functions. These results provided a new perspective for improving the growth performance of pigs.

Abstract

Accumulating evidences demonstrate that fermented feed and liquid feeding exerted a great beneficial influence on growth performance and health in the pig industry. This experiment was conducted to evaluate the effects of fermented liquid feeding on the growth performance and intestinal function of pigs. Two hundred and eighty-eight 27-day-old weaned piglets (8.21 ± 0.27 kg) were randomly allocated to a control group (basal diet (CON)), an antibiotic group (basal diet supplemented with antibiotics (AB)) and a fermented liquid feeding group (basal diet with fermented liquid feeding (FLF)), with 6 replicates per treatment and 16 weaned piglets per replicate. The experiment lasted for 160 days. Fresh fecal samples were collected to evaluate the apparent total tract digestibility (ATTD) of nutrients from the last 4 days of each stage. The results are shown as follows: (1) Compared with the CON group, in the whole stage, the FLF diet significantly increased the final body weight (BW) and ADG of pigs (P < 0.05), and had a tendency to increase ADFI (P = 0.086), but had no effect on F/G. (2) The ATTD of dry matter (DM), crude protein (CP), ether extract (EE), crude ash (CA), crude fiber (CF), gross energy (GE), calcium (Ca) and total phosphorus (TP) in the FLF group was significantly elevated compared with those of the CON group at 8–20 kg stage (P < 0.05). Meanwhile, the ATTD of EE in the FLF group was significantly increased compared with that of the CON group at the 50–75 kg and 100–125 kg stages (P < 0.05), and the ATTD of Ca was higher than that of CON group at the 100–125 kg stage (P < 0.05). (3) Compared with that of the CON group, the level of serum leptin in the FLF group had a tendency to decrease (P = 0.054), the level of serum ghrelin in the FLF group was significantly elevated (P < 0.05) and the level of serum peptide YY in the FLF group was significantly decreased (P < 0.05). (4) The abundance of Lactobacillus in cecal and colonic digesta was observably enhanced in FLF group. Meanwhile, the abundance of Escherichia coli in cecal and colonic digesta were dramatically reduced in the FLF group compared with that in the CON and AB groups (P < 0.05). (5) The levels of acetic acid in colonic digesta were significantly increased in the FLF group (P < 0.05), and an increasing trend was observed in total VFA in colonic digesta compared with CON (P < 0.1). The levels of acetic acid in colonic digesta were significantly promoted in the FLF group compared with that of the AB group (P < 0.05). In conclusion, these results indicate that fermented liquid feeding improved the growth performance of pigs, which might be associated with gastrointestinal hormone and intestinal functions.

An integrated method to produce fermented liquid feed and biologically modified biochar as cadmium adsorbents using corn stalks

The recycling of agricultural waste is a global challenge to the sustainable development of agriculture. By using corn stalks, we studied the feasibility of combining anaerobic fermentation and pyrolysis processes to produce both fermentated liquid feed and biologically modified biocharas cadmium adsorbents. Anaerobic ensiling enhanced the biodegradation of corn stalks by increasing crude protein and reducing fiber contents. After 24-h anaerobic fermentation, corn stalks silage was decomposed into the liquid filtrate and non-fermented residue. Fermented liquid feed (FLF) was prepared by storing feed and liquid filtrate (1:4.0, wt/wt) in a closed tank at 20 °C for 4 days, which showed desired properties (pH < 4.5, lactic acid bacteria greater than 9.0 lg cfu g^-1, lactic acid greater than 100 mmol L^-1). The non-fermented residue was pyrolyzed at 500 °C to prepare biologically modified biochar (BCB24). In comparison with pristine biochar produced from corn stalks (CB), anaerobic ensiling and anaerobic fermentation significantly increased the surface area, oxygen-containing functional groups, as well as mineral components in BCB24. The maximum sorption capacity of Cd(II) for BCB24 was 2.1 times of CB, suggesting that BCB24 is an effective adsorbent for Cd(II) removal from water. Our results indicated that coupling anaerobic fermentation and pyrolysis technology can significantly improve the efficiency of corn stalks recycling.

Effects of supplementation of high-dosing Trichoderma reesei phytase in the corn-wheat-soybean meal-based diets on growth performance, nutrient digestibility, carcass traits, faecal gas emission, and meat quality in growing-finishing pigs

We conduct this study to investigate the effects of corn-wheat-soybean meal (SBM)-based diet supplemented with high-dosing Trichoderma reesei phytase on the growth performance, nutrient digestibility, carcass traits, faecal gas emission and meat quality in growing-finishing pigs (29.71-110.58 kg live weight; 70-day-old to 166-day-old). A total of 56 crossbred pigs [(Landrace × Yorkshire) × Duroc] were used in 96-day experiment with a completely randomized block design. The growing period was from day 0 to 42, and the finishing period was from day 43 to 96. Pigs were randomly allocated to one of two treatments with seven replicate pens and four pigs (two barrows and two gilts) per pen and fed corn-wheat-SBM-based nutrient adequate basal diet or the basal diet supplemented with 1500 FTU/kg diet Trichoderma reesei phytase. One phytase unit (FTU) was defined as the amount of enzyme that catalyses the release of one micromole phosphate from phytate per minute at 37°C and pH 5.5. Dietary supplement with Trichoderma reesei phytase had increased body weight on day 96 and average daily gain in days 0-96. Moreover, high apparent total tract digestibility (ATTD) of phosphorus (P) was observed in pigs fed with Trichoderma reesei phytase. However, the carcass traits, faecal gas emission and meat quality of pigs were unaffected by Trichoderma reesei phytase supplementation. In conclusion, supplementation of high-dosing Trichoderma reesei phytase (1500 FTU/kg diet) in the corn-wheat-SBM-based nutrient adequate basal diet increased body weight and the ATTD of P, while no adverse effects were observed on the production characteristics.

Fermentation of barley and wheat with lactic acid bacteria and exogenous enzyme on nutrient composition, microbial count, and fermentative characteristics

Characteristics of wheat and barley inoculated with a homo-fermentative (HO) or hetero-fermentative (HE) lactic acid bacteria (LAB) were investigated in separate 97 d studies conducted using a 3 × 2 factorial arrangement comparing inoculants (no inoculant, HO or HE) and multi-enzyme (no or yes) addition. The pH declined (P < 0.05) to below 4.5 by day 6, coinciding with peaks in lactobacilli and yeast counts. A more rapid decline (P < 0.05) in pH and lactobacilli count but higher (P < 0.05) yeast count was observed with HO relative to HE. Enzyme addition reduced pH in inoculated grains only, particularly with HE (inoculant × enzyme effect; P < 0.05). Higher dry matter losses (P < 0.05) were observed with HE, most apparent in barley. Lactate was generally highest in HO and was increased by enzyme addition. Acetate was higher (P < 0.05) in HE. Ethanol and ammonia were lowest (P < 0.05) in HO. Wheat neutral detergent fibre (NDF) was reduced by both inoculants compared with control, whereas enzyme addition reduced NDF content in both grains. In conclusion, although not marked, fermentation responses appeared greater in wheat than barley although either LAB inoculant improved grain fermentation characteristics. The multi-enzyme appeared active during fermentation.

Microbiome Analysis Investigating the Impacts of Fermented Spent Mushroom Substrates on the Composition of Microbiota in Weaned Piglets Hindgut

The purpose of this study was to investigate the effects of fermented spent mushroom substrates (FSMS) on growth performance, serum biochemical, gut digestive enzyme activity, microbial community, genes expression of tight junction proteins, and volatile fatty acids in the hindgut (colon and cecum) of weaned piglets. A total of 100 weaned Yihao native pigs (native × Duroc, 50 males and 50 females) were allocated to two groups with five replicates and 10 pigs per replicate. Pigs in the control group were fed a basal diet (BD group), and the others were fed basal diets supplemented with 3% FSMS (FSMS group). Relative to the BD group, it had better results for final weight, average daily gain, and feed conversion ratio in the FSMS group but not significant (p > 0.05), which was accompanied by improved serum triiodothyronine, immunoglobulin G, and immunoglobulin A (p < 0.05) but lower serum total protein, albumin, total cholesterol, and total triglyceride during the overall period (p < 0.05). Similarly, FSMS significantly upregulated (p < 0.05) the messenger RNA expression of duodenal tight junction proteins such as tight junction protein 1, tight junction protein 2, and occludin. Meanwhile, isobutyric acid, valeric acid, and isovaleric acid levels were increased, whereas propanoic acid was decreased (p < 0.05) in the FSMS group than the BD group. In addition, the piglets in the FSMS group changed the microbial diversity in the colon and cecum. 16S rRNA gene sequencing-based compositional analysis of the colonic and cecal microbiota showed differences in the relative abundance of bacterial phyla (Firmicutes, Bacteroidetes, etc.), genus (Lactobacillus, Streptococcus, Roseburia, etc.), and species (Lactobacillus gasseri, Clostridium disporicum, etc.) between the BD and FSMS fed piglets. In conclusion, dietary supplementation with FSMS benefited to the intestinal mucosal barrier, immunity, and composition of the microbiota.

Growth Performance, Gut Environment and Physiology of the Gastrointestinal Tract in Weaned Piglets Fed a Diet Supplemented with Raw and Fermented Narrow-Leafed Lupine Seeds

Simple Summary

Fermented feed in growing pig nutrition may influence microbiota of the gastrointestinal tract, improve utilization of nutrients from the diet, and reduce the level of excreted ammonia and phosphorus released into the environment. In the research, fermentation of narrow-leafed lupine seeds was provided and fermented seeds were added to the pigs’ diet. In the 28-day experiment, 24 male pigs were divided into three groups. The control group was fed a soybean meal diet, whereas in the experimental diets, 50% of soybean meal (SBM) protein was replaced by raw or fermented lupine seeds. The influence of fermentation on performance results, gut environment and physiology, and selected blood metabolic parameters in young pigs, were analyzed. Fermentation did not affect pigs’ performance, metabolic, microbial and most gastrointestinal tract parameters, but influenced crypt depth, concentrations of short chain fatty acids and p-cresole in the proximal colon segment, and significantly lowered the pH of the middle colon digesta and ammonia contents. Fermentation improved the chemical composition of seeds, but due to the lack of a significant improvement in the performance, the results may prove to be economically unviable.

Abstract

The aim of this study was to: (1) provide controlled fermentation of narrow-leafed lupine seeds; (2) monitor seed composition, and (3) determine the influence of fermentation on the performance, gut environment and physiology, and selected blood metabolic parameters, in young pigs. Firstly, the effect of 24 h lupine seed fermentation by bacteria and yeast on seed chemical composition was determined. It increased contents of crude protein, crude fiber and ash, but reduced nitrogen-free extractive levels. The amino acid profile of fermented lupine (FL) was similar to that of raw lupine (RL) seeds, whereas the contents of oligosaccharides and P-phytate decreased significantly, in contrast to alkaloids. In fermented feed, pH dropped from 5.5 to 3.9. In the 28-day experiment, 24 male pigs were divided into three groups. The control group was fed a soybean meal diet (SBM), whereas in the experimental diets, 50% of SBM protein was replaced by RL or FL. Afterwards, eight pigs from each group were euthanized and their digesta and blood samples were collected. The FL use did not affect pigs’ performance, nor their metabolic, microbial and most gastrointestinal tract parameters, but influenced crypt depth. Fermentation affected concentrations of short chain fatty acids and p-cresole in the proximal colon segment. In the small intestine, the levels of acetate and butyrate decreased, and, in the caecum, the propionate level decreased. Fermentation significantly lowered the pH of the middle colon digesta and ammonia contents compared to RL. A part of SBM may be successfully replaced by RL and FL in young pigs’ diets.

Influence of Fermented Diets on In Vitro Survival Rate of Some Artificially Inoculated Pathogens—A Preliminary Study

Improving the hygienic status of feed ingredients by biotechnological processes as fermentation is of the greatest concern. This preliminary study aimed to investigate whether there are relevant effects of fermented liquid feed (FLF) on the survival of potential pathogens in vitro. The feed (fresh basis) consisted of 50% rye, 30% rapeseed extracted meal, 10% barley and 10% wheat. Glass bottles were filled about 14.1 g water (38 °C) containing the diluted starter culture and feed (8.81 g). Fermentation led to high levels of lactate (5–7% of dry matter), low pH values (<4.0) and low levels of acetic acid (<1% of dry matter) in the FLF. The survival rate of pathogens added, such as Salmonella enterica serovar Typhimurium, Escherichia coli and Clostridium perfringens after 6 h of controlled fermentation, was significantly reduced (<2 log10 CFU/g). The counts of Candida krusei in FLF at 3 h and 6 h post inoculation remained almost unchanged regardless of the incubation time. Even adding sodium-benzoate at a concentration of up to 0.25% in the liquid feed did not reduce the survival of C.krusei during fermentation. Based on this in vitro study, feeding of FLF seems a promising strategy to reduce pathogen transmission but has to be confirmed on natural feeds by pathogens for increasing the hygienic properties.

Combination of Antimicrobial Starters for Feed Fermentation: Influence on Piglet Feces Microbiota and Health and Growth Performance, Including Mycotoxin Biotransformation in vivo

The aim of this study was to apply a combination of the microbial starters Lactobacillus uvarum LUHS245, Lactobacillus casei LUHS210, Pediococcus acidilactici LUHS29, and Pediococcus pentosaceus LUHS183 for feed fermentation and to evaluate the influence of fermentation on feed acidity and microbiological characteristics, as well as on the piglet feces microbiota, health, and growth performance. Additionally, mycotoxin biotransformation was analyzed, including masked mycotoxins, in feed and piglet feces samples. The 36-day experiment was conducted using 25-day-old Large White/Norwegian Landrace (LW/NL) piglets with an initial body weight of 6.9–7.0 kg, which were randomly distributed into two groups (in each 100 piglets): control group, fed with basal diet (based on barley, wheat, potato protein, soybean protein concentrate, and whey powder), and treated group, fed with fermented feed at 500 g kg⁻¹ of total feed. Compared to a commercially available lactic acid bacteria (LAB) combination, the novel LAB mixture effectively reduced feed pH (on average pH 3.65), produced a 2-fold higher content of L(+) lactic acid, increased viable LAB count [on average 8.8 log₁₀ colony-forming units (CFU) g⁻¹], and led to stable feed fermentation during the entire test period (36 days). Fecal microbiota analysis showed an increased number of probiotic bacteria in the treated group, particularly Lactobacillus, when compared with the control group at the end of experiment. This finding indicates that fermented feed can modify microbial profile change in the gut of pigs. In treated piglets' blood (at day 61), the serum high-density lipoprotein (HDL) cholesterol and triglycerides (TG) were significantly higher, but the levels of T4, glucose, K, alkaline phosphatase (AP), and urea were significantly decreased (p ≤ 0.05) compared with the control group. Mycotoxin analysis showed that alternariol monomethyl ether (AME) and altenuene were found in 61-day-old control piglets' feces and in fermented feed samples. However, AME was not found in treated piglets' feces. Feed fermentation with the novel LAB combination is a promising means to modulate piglets' microbiota, which is essential to improve nutrient absorption, growth performance, and health parameters. The new LAB composition suggests a novel dietary strategy to positively manipulate fermented feed chemicals and bio-safety and the piglet gut microbial ecology to reduce antimicrobials use in pig production and increase local feed stock uses and economical effectiveness of the process.

Prevotella in Pigs: The Positive and Negative Associations with Production and Health

A diverse and dynamic microbial community (known as microbiota) resides within the pig gastrointestinal tract (GIT). The microbiota contributes to host health and performance by mediating nutrient metabolism, stimulating the immune system, and providing colonization resistance against pathogens. Manipulation of gut microbiota to enhance growth performance and disease resilience in pigs has recently become an active area of research in an era defined by increasing scrutiny of antimicrobial use in swine production. In order to develop microbiota-targeted strategies, or to identify potential next-generation probiotic strains originating from the endogenous members of GIT microbiota in pigs, it is necessary to understand the role of key commensal members in host health. Many, though not all, correlative studies have associated members of the genus Prevotella with positive outcomes in pig production, including growth performance and immune response; therefore, a comprehensive review of the genus in the context of pig production is needed. In the present review, we summarize the current state of knowledge about the genus Prevotella in the intestinal microbial community of pigs, including relevant information from other animal species that provide mechanistic insights, and identify gaps in knowledge that must be addressed before development of Prevotella species as next-generation probiotics can be supported.

Intestinal Microbiota of Fattening Pigs Offered Non-Fermented and Fermented Liquid Feed with and without the Supplementation of Non-Fermented Coarse Cereals

Introducing high numbers of lactic acid bacteria into the gastrointestinal tract of pigs via fermented liquid feed (FLF) could have an impact on intestinal bacterial ecosystems. Twenty piglets were allocated into four groups and fed a botanically identical liquid diet that was offered either non-fermented (twice), fully fermented or partially fermented but supplemented with 40% of non-fermented coarse cereals. Microbiota studies were performed on the small and large intestine digesta and faecal samples. A 16S rRNA gene amplification was performed within the hypervariable region V4 and sequenced with the Illumina MiSeq platform. R (version 3.5.2) was used for the statistical analyses. The digesta of the small intestines of pigs fed FLF were dominated by Lactobacillaceae (relative abundance up to 95%). In the colonic contents, the abundance of Lactobacillaceae was significantly higher only in the pigs fed the FLF supplemented with non-fermented coarse cereals. Additionally, the digesta of the small and large intestines as well as in the faeces of the pigs fed the FLF supplemented with non-fermented coarse cereals were significantly enriched for two operational taxonomic units (OTUs) belonging to the genus Lactobacillus and Bifidobacterium. The FLF supplemented with non-fermented coarse cereals had probiotic and prebiotic-like impacts on the intestinal and faecal bacterial composition of pigs.

Effect of temperature on single- and mixed-strain fermentation of ruminant feeds

Use of raw feedstuffs for livestock is limited by low digestibility. Recently, fermentation of feedstuffs has been highlighted as a new way to improve nutrient absorption through the production of organic acids using inoculated microorganisms, which can also play a probiotic role. However, standard procedures for feedstuff fermentation have not been clearly defined because the process is influenced by climatic variation, and an analytical standard for fermented feedstuffs is lacking. This study aimed to evaluate the microbiological and biochemical changes of feedstuffs during fermentation at temperatures corresponding to different seasons (10°C, 20°C, 30°C, and 40°C). We also investigated the effects of yeast, lactic acid bacteria (LAB), and Bacillus spp. on fermentation and determined the results of their interactions during fermentation. The viable cells were observed within 8 days in single-strain fermentation. However, when feedstuffs were inoculated with a culture of mixed strains, LAB were predominant at low temperatures (10°C and 20°C), while Bacillus spp. was predominant at high temperatures (30°C and 40°C). A significant drop in pH from 6.5 to 4.3 was observed when LAB was the dominant strain in the culture, which correlated with the concentrations of lactic acid. Slight ethanol production was detected above 20°C regardless of the incubation temperature, suggesting active metabolism of yeast, despite this organism making up a marginal portion of the microbes in the mixed culture. These results suggested that fermentation temperature significantly affects microbiological profiles and biochemical parameters, such as pH and the lactic acid concentration, of fermented feedstuffs. Our data provide valuable information for the determination of industrial standards for fermented feedstuffs.

Effects of Increasing Doses of Lactobacillus Pre-Fermented Rapeseed Product with or without Inclusion of Macroalgae Product on Weaner Piglet Performance and Intestinal Development

This study evaluated the effects of increasing doses of pre-fermented rapeseed meal (FRM) without or with inclusion of the brown macroalgae Ascophyllum nodosum (AN) on weaner piglets' performance and gut development. Ten days pre-weaning, standardized litters were randomly assigned to one of nine isoenergetic and isoproteic diets comprising (on DM basis): no supplement (negative control, NC), 2500 ppm ZnO (positive control, PC), 8, 10, 12, 15 or 25% FRM, and 10% FRM plus 0.6 or 1.0% AN. Fifty piglets receiving the same pre-weaning diets were weaned at 28 days of age and transferred to one pen, where they continued on the pre-weaning diet until day 92. At 41 days, six piglets per treatment were sacrificed for blood and intestinal samplings. The average daily gain was at least sustained at any dose of FRM (increased at 8% FRM, 28-41 days) from 18-41 days similar to PC but unaffected by inclusion of AN. The percentage of piglets that completed the experiment was increased by FRM compared to NC, despite detection of diarrhea symptoms. FRM showed quadratic dose-response effects on colon and mid-jejunum crypts depth, and enterocyte and mid-jejunum villus heights with optimum development at 8% or 10% FRM, respectively, but this was abolished when AN was also added. In conclusion, FRM sustained piglet growth performance and intestinal development similar to ZnO with an optimum inclusion level of 8-10% of dietary DM.

Allergenicity reduction and rheology property of Lactobacillus-fermented soymilk

BACKGROUND

This study aimed to investigate the reduction in the potential allergenicity of soymilk, and its rheological properties, after fermentation with Lactobacillus. Soymilk (SM) was fermented with Lactobacillus brevis and Lactobacillus sp. The molecular weight of fermented soymilk (FSM) was characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and the potential allergenicity of FSM was analyzed using enzyme-linked immunosorbent assay in vitro and the BALB/c mouse model to detect changes in histamine, mouse mast cell protease-1 (mMCP-1), allergen-specific IgG/IgE, and cytokine levels and histomorphology of jejunum in vivo.

RESULTS

The SDS-PAGE and enzyme linked immunosorbent assay (ELISA) showed that allergens of soybean (β-conglycinin and acidic subunit of glycinin) were almost degraded, and their immunoreactivity was decreased. In the BALB/c mouse model, the FSM group did not show anaphylactic shock symptoms compared with the SM group. Moreover, a tendency toward decreased serum allergen-specific IgG/IgE levels, plasma histamine levels, and mMCP-1 concentrations was observed in the FSM group. Furthermore, Th2-related cytokines were decreased, while IFN-γ production increased in spleen cell cultures. The intestinal villus was slightly damaged after the challenge. All these findings indicated that the Th1/Th2 balance in the FSM group shifted toward a Th1 response, ultimately reducing the potential allergenicity of FSM. Rheological assessment suggested that FSM has good viscous and pseudoplastic properties.

CONCLUSION

Fermentation might be a promising method for producing tasty, hypoallergenic soybean products. © 2019 Society of Chemical Industry.

Improvement of the Quality of Ginkgo biloba Leaves Fermented by Eurotium cristatum as High Value-Added Feed

Ginkgo biloba leaves are well known for their high content of nutrients and bioactive substances. However, unpleasant smell and a small number of ginkgolic acids greatly reduce the utilization of the leaves. In this work, solid-state fermentation of G. biloba leaves using Eurotium cristatum was studied by investigation of the nutrient changes and its feasibility as a functional feed. E. cristatum could grow on pure G. biloba leaves and the addition of excipients could significantly improve the growth of E. cristatum. The optimal medium was with 10% (w/w) of whole G. biloba seeds and the optimized water content, pH, inoculum size and fermentation time were 45% (w/w), 4.5, 4.76 × 107 CFU/100 g wet medium, and eight days, respectively. Under the optimal conditions, the spore number increased by about 40 times. The content of flavonoids was greatly increased by 118.6%, and the protein and polyprenyl acetates (PPAs) were increased by 64.9% and 10.6%, respectively. The ginkgolic acids, lignin, and cellulose were decreased by 52.4%, 38.5%, and 20.1% than before, respectively. Furthermore, the fermented G. biloba leaves showed higher antioxidant activity and held more aroma substances. Thus, G. biloba leaves fermented by E. cristatum have potential as s high value-added feed. This is the first investigation of E. cristatum fermentation on ginkgo leaves, which will facilitate the use of ginkgo leaves in the feed industry.

Effect of fermented blood cells on growth performance and intestinal characteristics of weaned piglets

The increase in feed costs has led feeder to replace protein source. Blood meal can be used in piglet diets instead of fish meal (FM). The objective of this study was to investigate the effect of fermented blood cells (FBCs) on the growth performance and intestinal health of weaned piglets. One hundred eighty 28-day-old piglets were assigned and were divided into 4 groups (9 L per groups and 5 pigs per litters) randomly. The piglets were fed one of four experimental diets, fish meal, blood cells (BCs), liquid-state fermented blood cells (LFBCs) or solid-state fermented blood cells (SFBCs) respectively. The dietary with LFBCs and SFBCs increased the average daily gain and feed intake (ADFI) and average daily gain (ADG) (p < .05). In duodenum, LFBC group increased the villous height (p < .05). The SFBC and LFBC group significantly increased the villous height (p < .05) in the jejunum. Fermented blood cells exhibit a positive regulatory function on the intestinal tract and modulate intestinal microflora. Compared with the fish meal group, the CAT, GSH-PX and SOD activity, and MDA level was no significant differences in jejunum and plasma of weaned piglets (p > .05). LFBCs and SFBCs significantly increased the bifidobacteria and lactobacillus number in the caecum (p < .05). Dietary LFBCs increased the expression of ZO-1 mRNA in the jejunal of weaned piglets (p < .05). In conclusion, dietary with fermented blood cells in weaned piglets had improved growth performance and intestinal health of weaned piglets.

Health-promoting effects of Lactobacillus-fermented barley in weaned pigs challenged with Escherichia coli K88. Animal 2019;14:39-49. [PMID: 31426877 DOI: 10.1017/s1751731119001939]

Fermented feeds are being considered as practical alternatives to antimicrobial growth promoters (AGP) supplemented in nursery pig diets. This study aimed to investigate health-promoting effects of fermented barley in weaned pigs challenged with Escherichia coli K88 +. A total of 37 piglets were weaned at 21 ± 1 day of age (6.41 ± 0.47 kg of BW) and assigned to either of the following five treatment groups: (1) unchallenged control (UCC; n = 7), (2) challenged control (CC; n = 7), (3) AGP (CC + 0.1% AGP; n = 7), (4) Ferm1 (challenged and fed homofermentative Lactobacillus plantarum (Homo)-fermented barley; n = 8) and (5) Ferm2 (challenged and fed heterofermentative L. buchneri (Hetero)-fermented barley; n = 8). The control diet included unfermented barley. Barley was fermented with either Homo or Hetero for 90 days under anaerobic conditions. On day 10, all pigs except those in UCC group were orally inoculated with E. coli K88 + (6 × 109 colony forming units/ml). The pre-planned orthogonal test was performed to compare (1) UCC and CC, (2) CC and AGP, (3) CC and Ferm1 + Ferm2, as well as (4) Ferm1 and Ferm2. Challenged control pigs showed shorter (P < 0.05) villus height (VH) in the duodenum and deeper (P < 0.05) crypt depth (CD) in the jejunum than UCC pigs. The AGP group had higher (P < 0.05) VH and lower (P < 0.05) IL-6 gene expression in the jejunum compared with CC group. Compared to CC, Ferm1 and Ferm2 had decreased (P < 0.05) CD in the duodenum, IL-6 gene expression in the jejunum and rectal temperature at 24 h post-challenge. Pigs fed fermented barley diets showed greater (P < 0.05) faecal abundance of Clostridium Cluster IV and Lactobacilli than those fed UCC diet. Ferm2-fed pigs showed lower (P < 0.05) concentrations of band cells, eosinophils and lymphocytes at 6, 24 and 48 h after challenge, respectively, and lower (P < 0.05) faecal abundance of Enterobacteriaceae 24 h after challenge than the Ferm1-fed pigs. In conclusion, the substitution of unfermented barley with fermented barley in a nursery diet showed similar results as those shown by AGP supplementation in terms of enhancing the intestinal morphology and modulating faecal microbiota composition, as well as down-regulating the pro-inflammatory cytokines; therefore, fermented barley can be a possible nutritional strategy for managing nursery pigs fed diets without in-feed AGP.

Effect of increasing levels of rice distillers' by-product on growth performance, nutrient digestibility, blood profile and colonic microbiota of weaned piglets

OBJECTIVE

This study was conducted to evaluate the effects of diets containing different wet rice distillers' by-product (RDP) levels on growth performance, nutrient digestibility, blood profiles and gut microbiome of weaned piglets.

METHODS

A total of 48 weaned castrated male crossbred pigs, initial body weight 7.54±0.97 kg, and age about 4 wks, were used in this experiment. The piglets were randomly allocated into three iso-nitrogenous diet groups that were fed either a control diet, a diet with 15% RDP, or a diet with 30% RDP for a total of 35 days. Chromium oxide was used for apparent digestibility measurements. On d 14 and d 35, half of the piglets were randomly selected for hemato-biochemical and gut microbiota evaluations.

RESULTS

Increasing inclusion levels of RDP tended to linearly increase (p≤0.07) average daily gain on d 14 and d 35, and decreased (p = 0.08) feed conversion ratio on d 35. Empty stomach weight increased (p = 0.03) on d 35 while digestibility of diet components decreased. Serum globulin concentration decreased on d 14 (p = 0.003) and red blood cell count tended to decrease (p = 0.06) on d 35, parallel to increase RDP levels. Gene amplicon profiling of 16S rRNA revealed that the colonic microbiota composition of weaned pigs changed by inclusion of RDP over the period. On d 14, decreased proportions of Lachnospiraceae_ge, Ruminococcaceae_ge, Ruminococcaceae_UCG-005, and Bacteroidales_ge, and increased proportions of Prevotellaceae_ge, Prevotella_2, and Prevotella_9 were found with inclusion of RDP, whereas opposite effect was found on d 35. Additionally, the proportion of Lachnospiraceae_ge, Ruminococcaceae_ge, Ruminococcaceae_UCG-005, and Bacteroidales_ge in RDP diets decreased over periods in control diet but increased largely in diet with 30% RDP.

CONCLUSION

These results indicate that RDP in a favorable way modulate gastrointestinal microbiota composition and improve piglet performance despite a negative impact on digestibility of lipids and gross energy.

Bioprocessed poultry by-product meals on growth, gut health and fatty acid synthesis of juvenile barramundi, Lates calcarifer (Bloch)

Poultry by-product meal (PBM) has been utilised as a substitute of fishmeal (FM) in many aquaculture species. However, little information is known regarding the use of bioprocessed PBM (BPBM) in aquaculture production. This study was undertaken to investigate whether replacing FM with BPBM improved growth performance, gut morphology and fatty acid synthesis of juvenile barramundi, Lates calcarifer. The PBM was bioprocessed by baker yeast, Saccharomyces cerevisae and Lactobacillus casei. The BPBM was used to replace FM at 75% and 100% (75BPBM and 100BPBM) contrasting against unprocessed PBM (75PBM and 100PBM) at the same levels and FM based diets as the control. Juvenile barramundi with a mean initial weight of 3.78±0.16 g were stocked at a density of 20 fish per tank. After the 42 days of study, the final weight, specific growth rate and feed conversion ratios of fish fed 75PBM and 75BPBM were not significantly different from the control. However, 100% supplementation diets of 100PBM and 100BPBM resulted in reduced performance in all growth and feed variables except total feed intake and survival. The hind gut microvillus density was significantly higher (P<0.05) in fish fed 75BPBM, whereas the microvillus diameter remained unaffected with the other experimental diets when compared to the control. A reduction in eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids of fish muscles led to a lower Σn-3/Σn-6 ratio in all dietary groups when compared to the control. The percentage of Σn-3 PUFAs decreased in 100% FM replacement diets of 100PBM and 100BPBM, while Σn-6 PUFAs increased when both bioprocessed and unprocessed PBM protein was increased in the diets. Fish fed bioprocessed diets had higher fatty acid hypocholesterolemic/hypercholesterolemic ratios (HH), indicating improved suitability for human consumption.

Effect of dietary fermented oats in different nutrient-density diets on growth performance, nutrient digestibility and ileal microorganisms of weanling pigs

A total of 160 crossbred weanling pigs [(Landrace × Yorkshire) × Duroc, 28 days old] with an initial bodyweight of 8.01 ± 0.74 kg were used in a 42-day trial (Phase 1: Days 1–14, Phase 2: Days 14–42). The experiment was conducted to evaluate the effects of the inclusion of fermented oats (FO) to a corn and soybean meal-based diet on the performance of weanling pigs fed with high nutrient-density (HD) and low nutrient-density (LD) diets. Pigs were randomly distributed into one of four dietary treatments in a 2 × 2 factorial arrangement. Two levels of nutrient density [LD = 3323 (Phase 1: 1–14 days) and 3269 kcal/kg (Phase 2: 14–42 days); HD = 3446 (Phase 1: 1–14 days) and 3325 kcal/kg (Phase 2: 14–42 days), the differences in dietary energy were based on differences in the content of fish meal, animal fat, corn and FO [0%, 5% (Phase 1) or 2.5% (Phase 2)] were used according to the bodyweight and sex of pigs [8 replicate pens per treatment with 5 pigs in a pen (3 gilts and 2 barrows)]. During the overall trial period (Days 1–42), the average daily gain and gain:feed ratio of pigs fed HD and FO diets were significantly higher (P ≤ 0.05) than those of pigs fed with LD and non-fermented oats diets respectively. On Day 14, the apparent total tract digestibility of dry matter and nitrogen of the HD groups were significantly greater (P ≤ 0.05) than those of the LD groups. The apparent total tract digestibility of energy of the FO groups was significantly greater (P ≤ 0.05) than that of the non-fermented oats diet groups during the whole experimental period. Pigs fed with FO showed higher (P ≤ 0.05) ileal Lactobacillus and lower (P ≤ 0.05) Escherichia coli counts compared with those fed with the non-fermented oats diet. In conclusion, administration of FO to a LD diet demonstrated beneficial effects on the growth performance, nutrient digestibility and ileal microorganisms balance of weanling pigs.

Solid-state fermentation of distilled dried grain with solubles with probiotics for degrading lignocellulose and upgrading nutrient utilization

Solid-state fermentation (SSF) was carried out in this study to improve the nutritional digestibility of two types of distilled dried grain with solubles (DDGS) by inoculating probiotic combinations. The fermented DDGS (FDDGS) contained more crude protein, small peptides and total amino acids than did unfermented DDGS. The concentrations of fiber indexes significantly declined after fermentation. The amounts of probiotics, enzymes and organic acids were significantly improved after fermentation. Microscopy revealed that SSF disrupted the surface structure and increased small fragments of DDGS substrate, thereby facilitating in vitro digestibility of FDDGS. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and high-performance liquid chromatography indicated the breakdown of macromolecular protein and lignocellulose, which contributed to the increase of small peptides and monosaccharides. These findings suggested the great potential of SSF to promote the nutritional quality and digestibility of the two DDGS and to expand their utilization.

Energy content and nutrient digestibility of diets containing Lactobacillus-fermented barley or wheat fed to weaned pigs

This study was conducted to determine the energy content and apparent total tract digestibility (ATTD) of nutrients of diets containing Lactobacillus-fermented barley or wheat fed to weaned pigs. Thirty-six weaned pigs (8.14 ± 0.65 kg of body weight) were randomly assigned to 1 of 6 diets in a completely randomized design to give 6 replicates per diet. Pigs were individually housed in metabolism crates to determine digestible energy and metabolizable energy contents. Net energy was also calculated from the average of 2 equations published by Noblet et al. (1994). Diets were fed at 2.5 times the maintenance energy requirement for 10 d of adaptation and 5 d of total but separate urine and fecal collection. Samples of barley or wheat were fermented for 90 d under anaerobic conditions with an inoculum of either homofermentative Lactobacillus plantarum (Homo) or heterofermentative L. buchneri (Hetero). Three diets were formulated based on either barley or wheat to consist of a control diet containing 42% unfermented grain and 2 diets containing either Homo-fermented or Hetero-fermented grain. Preplanned contrasts were used to evaluate the effects of the inclusion of fermented barley or wheat and to compare the effects of Homo-fermented with Hetero-fermented grains. Fermented wheat inclusion in a diet increased ATTD of gross energy and phosphorus, and retention of gross energy by 1.9%, 6.8%, and 6.3%, respectively. Also, fermented wheat diets had greater (P < 0.05) metabolizable energy content and tended to have greater (P ≤ 0.10) net energy content than unfermented wheat diets. However, inclusion of fermented barley did not increase nutrient and energy digestibility. Hetero-fermented diets contained greater (P < 0.05) digestible energy and net energy content (DM basis) than Homo-fermented diets. Pigs fed barley-based diets showed less (P < 0.05) ATTD of DM, nitrogen, and gross energy than those fed wheat-based diets. In conclusion, wheat fermented with Lactobacillus-inoculum can be beneficially substituted for unfermented wheat, improving the ATTD of nutrient and energy, nitrogen retention, and energy content. Also, Hetero-inoculum is preferable to Homo-inoculum for grain fermentation considering greater energy content in weaned pigs.

Effect of dietary fermented corn in different energy dense diets on growth performance, nutrient digestibility, ileal microorganisms, and fecal noxious gas emission of growing pigs

This study evaluated the efficacy of fermented corn (FC) in growing pigs. One hundred twenty-eight growing pigs [(Landrace × Yorkshire) × Duroc)] with an initial body weight of 29.59 ± 1.34 kg were used in a 6 wk experiment. Pigs were assigned into one of four dietary treatments in a 2 × 2 factorial arrangement with two levels of nutrient density (high energy: 3.37 Mcal kg−1, or low energy: 3.29 Mcal kg−1) and FC (0% or 20% substitute for corn). Pigs fed diets with FC increased (P < 0.05) average daily gain (ADG) overall. Pigs fed with high-density (HD) diets increased (P < 0.05) ADG and gain to feed (G/F) ratio overall. Apparent total tract digestibility (ATTD) of dry matter (DM), gross energy (GE), and nitrogen (N) increased (P < 0.05) in pigs fed with FC diets compared with pigs fed the diets without FC. In addition, pigs fed with HD diets increased (P < 0.05) ATTD of DM and GE compared with low-density (LD) diets. Furthermore, pigs fed with HD diets had a higher (P < 0.05) ATTD of DM and GE than those fed with LD diets. Both LD and FC supplementation led to lower (P < 0.05) fecal gas emission content. Pigs fed FC diets increased ileal Lactobacillus concentration and decreased Escherichia coli concentration. An interactive effect between nutrient density diet and FC was observed on the G/F, Lactobacillus on ileal microorganisms, and nutrient digestibility. In conclusion, the results indicated that dietary supplementation of HD diets and FC improved performance in growing pigs.

Microbiota in fermented feed and swine gut

Development of alternatives to antibiotic growth promoters (AGP) used in swine production requires a better understanding of their impacts on the gut microbiota. Supplementing fermented feed (FF) in swine diets as a novel nutritional strategy to reduce the use of AGP and feed price, can positively affect the porcine gut microbiota, thereby improving pig productivities. Previous studies have noted the potential effects of FF on the shift in benefit of the swine microbiota in different regions of the gastrointestinal tract (GIT). The positive influences of FF on swine gut microbiota may be due to the beneficial effects of both pre- and probiotics. Necessarily, some methods should be adopted to properly ferment and evaluate the feed and avoid undesired problems. In this mini-review, we mainly discuss the microbiota in both fermented feed and swine gut and how FF influences swine gut microbiota.

Influence of feeding crimped kernel maize silage on the course of subclinical necrotic enteritis in a broiler disease model

This experiment was carried out with 375 male broilers (Ross 308) from days 1 to 28 to evaluate the influence of crimped kernel maize silage (CKMS) on the manifestation of subclinical necrotic enteritis, microbiota counts, organic acid production and relative weights of gastrointestinal segments. A necrotic enteritis disease model was applied. Birds were allocated into 3 different dietary treatments: a maize-based feed (MBF, control diet), and 2 diets supplemented with 15% (CKMS15) or 30% (CKMS30) of crimped ensiled kernel maize. The disease model involved a 10-time overdose of an attenuated live vaccine against coccidiosis given orally on day 17, followed by oral inoculation of Clostridium perfringens Type A (S48, 10⁸ to 10⁹ bacteria/bird) twice daily on days 18, 19, 20 and 21. Scoring of intestinal lesions was performed on days 22, 23, 25 and 28. Ileal and caecal digesta samples were collected for the quantification of selected bacterial groups and organic acids. The results showed that there was no effect of dietary treatments on small intestinal lesion scores (P > 0.05). Lesions scores peaked on days 23 and 25 and decreased again on day 28 (P = 0.001). No effect of age on microbiota counts was observed, but feeding of CKMS30 reduced the number of coliforms in ileal contents (P = 0.01). Dietary treatments did not affect organic acid concentrations in ileum and caeca, but there was an effect of age; butyric acid was higher on days 22, 23 and 25 than on day 28 (P = 0.04). Acetic acid and propionic acid concentrations in caeca were the highest on days 22 and 28 but the lowest on days 23 and 25. Relative gizzard and caeca weights were increased, and relative ileum weights were decreased when birds were fed CKMS30 (P < 0.05). In conclusion, the inclusion of CKMS in broiler diets had no effects on the course of necrotic enteritis but had potential benefits in terms of inhibition of potentially harmful microorganisms.

Changes of gut microbiota structure and morphology in weaned piglets treated with fresh fermented soybean meal

This study investigated the effects of dietary fresh fermented soybean meal (FSM) on the intestinal microbiota and metabolites, bacterial enzyme activity and intestinal morphology of weaning piglets. A total of 64 weaned piglets were randomly allocated into two treatments. A corn-soybean-based diet was used as the control and other treatment was fed the same basal diet containing 15% fresh FSM. The feeding trial lasted for 21 days. Bacterial community structure and diversity in the cecum and colon were assessed using pyrosequencing-based analysis. The results showed that the phylum level, Firmicutes, Bacteroidetes, Proteobacteria and Tenericutes were dominant in the cecum or colon. Gut Firmicutes increased, while Bacteroidetes and Proteobacteria decreased in the fresh FSM-fed piglets. At the genus level, the relative abundances of butyrate-producing bacteria, Lactobacillus and Prevotella were higher in both cecum and colon of fresh FSM fed piglets. Meanwhile, fresh FSM could promote the development of intestinal morphological and reduce the incidence of diarrhea. The results indicated that fresh FSM might change intestinal function by influencing intestinal microenvironment.

Promotion of Early Gut Colonization by Probiotic Intervention on Microbiota Diversity in Pregnant Sows

The aim of this work was to design a novel mixed probiotic culture for piglets and to evaluate its beneficial effect on the piglets' gut health. The possible mechanisms of probiotic activity, such as adhesion, competitive pathogen exclusion and influence on gut microbiota diversity were determined. Mixed probiotic starter culture is composed of three thermophilic lactic acid bacteria (LAB) strains: Lactobacillus helveticus BGRA43, Lactobacillus fermentum BGHI14 and Streptococcus thermophilus BGVLJ1-44. The strains BGVLJ1-44 and BGRA43 showed good technological properties (fast milk curdling, strong proteolytic activity). In addition, the strain BGVLJ1-44 produces exopolysaccharide (EPS), BGHI14 is heterofermentative LAB strain with significant immunomodulatory effect, while the strain BGRA43 showed strong antimicrobial activity against different pathogens and exhibited significantly higher level of adhesion to Caco-2 cells comparing to other two strains. Both lactobacilli strains BGRA43 and BGHI14 (p < 0.05), as well as probiotic combination (p < 0.01) significantly reduced the adhesion of Escherichia coli ATCC25922 to Caco-2 cells, while the strains BGVLJ1-44 (p < 0.01) and BGRA43 (p < 0.05) significantly reduced adhesion of Salmonella 654/7E (veterinary isolate). The results of farm trial revealed that treatment of sows with new fermented dairy probiotic influenced the piglets' gut colonization with beneficial bacteria and reduced the number of enterobacteriaceae in litters from some treated sows (no significant due to high variability among animals). Finally, this is the first study reporting that the treatment of sows with probiotic combination resulted in the improved microbiota diversity in neonatal piglets.

Effects of steeped or fermented distillers dried grains with solubles on growth performance in weanling pigs

Coproduct feeding value may be improved by enzyme and microbial inoculant treatment in liquid diets. Three experiments were conducted to assess growth performance in newly weaned 20-d-old pigs fed corn- and soybean meal-based diets with untreated, steeped, or partially fermented distillers dried grains with solubles (DDGS) from day of weaning. In Exp. 1, conventionally dry fed diets with untreated DDGS (DDGS) or without DDGS (Control) were fed. In Exp. 2, liquid diets (25% DM [75% moisture]) were fed with enzymes (β-glucanase and xylanase at 67.2 and 51.4 U/g DDGS, respectively) added to dry DDGS at the time of liquid feeding (UNSTP) or steeped with DDGS and added to liquid feed from d 5 to 12 of each batch prior to liquid feeding (STP). In Exp. 1 and 2 DDGS inclusion levels were 7.5% in phase 1 (d 0 to 7) and 25% in phase 2 (d 7 to 21) and phase 3 (d 21 to 35). In Exp. 3 liquid diets were fed with the Exp. 2 enzymes and silage inoculant (360,000 combined cfu and /g DDGS) added to dry DDGS at the time of liquid feeding (UNFER) or fermented with DDGS and added to liquid feed from d 1 to 7 of each batch before liquid feeding (FER). The inclusion levels of DDGS were 7.5% in phase 1 (d 0 to 7), 16.25% in phase 2 (d 7 to 21), and 25% in phase 3 (d 21 to 42 or 48). Experiment 3 diets were fed to light (LBW; 5.8 ± 0.6 kg) or heavy (HBW; 7.6 ± 0.8 kg) BW pigs at weaning, and results were analyzed separately. Pig BW and ADFI were measured weekly in each experiment. In Exp. 1, feeding diets with DDGS depressed ( < 0.05) ADFI on d 7 to 21 (491 vs. 375 ± 21 g DM/pig) and d 0 to 35 (456 vs. 405 ± 13 g DM/pig). In Exp. 2 growth performance was not affected. In Exp. 3 ADFI of HBW pigs was not affected. The HBW pigs fed FER had lower ( < 0.05) ADG and G:F on d 7 to 21 (323 vs. 264 ± 15 g/pig and 0.86 vs. 0.72 ± 0.02 g:g, respectively) and lower ( < 0.05) BW on d 21 (12.4 vs. 11.6 ± 0.2 kg) compared with HBW pigs fed UNFER. The LBW pigs fed FER had lower ( < 0.05) ADFI on d 0 to 7 and 7 to 21 (190 vs. 168 ± 3 and 318 vs. 273 ± 13 g DM/pig, respectively) and had greater ( < 0.05) ADG on d 42 to 48 (773 vs. 941 ± 60 g/pig) and BW on d 48 (24.5 vs. 25.8 ± 0.5 kg) compared with LBW pigs fed UNFER. Results show that up to 25% DDGS inclusion in weaning pig diets did not affect overall growth performance. Liquid-fed partially fermented DDGS had an influence on the growth performance of weanling pigs, particularly during the extended nursery period of pigs of light weaning weight in this study.