Growth performance and gastrointestinal microbial ecology responses of piglets receiving Saccharomyces cerevisiae fermentation products after an oral challenge with Escherichia coli (K88)

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.

The Administration of Inactivated and Stabilized Whole-Cells of Saccharomyces cerevisiae to Gestating Sows Improves Lactation Efficiency and Post-Weaning Antimicrobial Use

Increasingly hyperprolific sows and the need to reduce antibiotics represent challenges in pig farming. The aim of this work was to determine the effects of a postbiotic obtained from inactivated and stabilized whole-cells of Saccharomyces cerevisiae, administered during the sow's gestation, on the performance of the mother and litter. Maternal feed intake, productive parameters, colostrum quality and post-weaning piglets' health were assessed, including antibiotic consumption. The trial involved 183 sows, divided into two groups: (1) sows fed with a daily supplementation of postbiotic during gestation (n = 90); (2) sows without any supplement (n = 93). Piglets were followed up at two different post-weaning sites. The lactation efficiency of the treated sows improved by +5.9% (41.3 ± 11.4 vs. 35.4 ± 11.6%; p = 0.011). Lactating piglets' mortality was lower in the treated group (25.1 ± 16.7 vs. 28.8 ± 14.4%; p = 0.048). The same tendency was shown in both the weaning sites, together with a reduced antibiotic consumption in weaning site 1 (0.72 ± 0.25 vs. 1.22 ± 0.30 DDDvet/PCU; p = 0.047). The results suggest the role of this postbiotic administered to the mother in improving the health status of the piglets. Furthermore, lactation efficiency is suggested as an interesting parameter for assessing the efficiency of farming.

Evaluation of a Lactococcus lactis-based dried fermentation product administered through drinking water on nursery pig growth performance, fecal Escherichia coli virulence genes and pathotypes, antibiotic usage, and mortality

A total of 34,749 pigs were used in two experiments to evaluate the effects of a postbiotic dried fermentation product (DFP) administered through drinking water on nursery pig growth performance, antibiotic injection frequency, morbidity, mortality, fecal consistency, and characterization of fecal Escherichia coli. The DFP is composed of bioactive molecules derived from Lactococcus lactis. In Exp. 1, 350 barrows (DNA Line 200 × 400; initial body weight [BW] 6.1 ± 0.01 kg) were used in a 42-d study with five pigs per pen and 35 pens per treatment. The DFP was supplied for 14 d at a target dosage of 24 mg/kg BW using a water medicator at a 1:128 dilution. On days 7 and 14, fecal samples were collected for dry matter (DM) and to determine, by a multiplex polymerase chain reaction (PCR) assay, prevalence of 11 virulence genes characteristic of E. coli pathotypes. There was no evidence (P > 0.10) for differences for growth, incidence of diarrhea, number of antibiotic injections, removals, or fecal DM. On both fecal collection days, E. coli virulence genes were present with day 7 samples positive for genes that encode for hemolysins (hlyA, exhA), intimin (eae), and enteroaggregative heat-stable enterotoxin (astA). Prevalence of enterotoxin genes (elt, estA, estB, astA) increased on day 14, but DFP had no effects on the prevalence of any of the virulence genes. A total of 32 out of 72 E. coli isolates were identified as enterotoxigenic pathotype and all except one were from day 14 fecal samples. Fourteen isolates were positive for F4 fimbria and one isolate was positive for F4 and F18 fimbriae. In Exp. 2, 34,399 nursery pigs (initially 5.6 kg) were used in 20 nursery barns with 10 barns per treatment (control or DFP). The target dosage of the DFP for the first 14 d was 35 mg/kg BW. Following the 14-d supplementation period, pigs continued to be monitored for approximately 31 d. There was no evidence (P > 0.05) for the DFP to influence the overall percentage of pigs that died or growth performance. From days 0 to 14, providing the DFP reduced (P < 0.05) the percentage of pigs that were euthanized. However, providing the DFP increased (P < 0.05) the overall percentage of pigs that were euthanized and total mortality. For the number of antibiotic injections (treatment interventions), providing the DFP reduced the number of injections for the common period (P < 0.001) and overall (P = 0.002). These results indicate that the DFP did not influence growth performance but providing the DFP in Exp. 2 led to increased total nursery pig mortality.

Development of an In Vivo Extended-Spectrum Cephalosporin-Resistant Escherichia coli Model in Post-Weaned Pigs and Its Use in Assessment of Dietary Interventions

Current interventions targeting antimicrobial resistance (AMR), a major impact on commercial pork production, focus on reducing the emergence of AMR by minimising antimicrobial usage through antimicrobial stewardship and a range of alternative control methods. Although these strategies require continued advancement, strategies that directly aim to reduce or eliminate existing antimicrobial resistant bacteria, specifically bacteria resistant to critically important antimicrobials (CIAs), need to be investigated and established. This study established an in vivo model for examining the effects of postbiotics, in the form of Lactobacillus acidophilus fermentation products (LFP) and Saccharomyces cerevisiae fermentation products (SFP), on the shedding of extended-spectrum cephalosporin (ESC)-resistant E. coli. The model was successful in demonstrating the presence of ESC-resistant E. coli as evidenced by its detection in 62 of 64 pigs. There was a strong trend (p = 0.065) for the SFP postbiotics to reduce the shedding of ESC-resistant E. coli, indicating positive impacts of this additive on reducing the carriage of bacteria resistant to CIAs. Overall, this in vivo model enables future evaluation of strategies targeting ESC-resistant E. coli while increasing our knowledge on the carriage of ESC-resistant E. coli in pigs.

Looking for Possible Benefits of Combining Short-Chain Fructo-Oligosaccharides (scFOS) with Saccharomyces cerevisiae Sc 47 on Weaned Pigs Orally Challenged with Escherichia coli F4. Animals (Basel) 2023;13:ani13030526. [PMID: 36766416 PMCID: PMC9913220 DOI: 10.3390/ani13030526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

The objective of this work was to evaluate the effect of supplementing short-chain fructo-oligosaccharides (scFOS) combined or not with live yeast Saccharomyces cerevisiae Sc 47 on weanling pigs challenged with Escherichia coli F4⁺. We allocated ninety-six piglets to four experimental diets: control (CTR); supplemented with scFOS (5 g/kg Profeed^® P95) (scFOS); S. cerevisiae Sc 47 (1 g/kg Actisaf^® Sc 47 HR +) (YEA); or both (SYN). Parameters included: performance; E. coli F4⁺ detection; fermentation activity; inflammatory biomarkers; and ileal histomorphology. Our results showed that supplementing scFOS was able to reduce the incidence of diarrhea, and both supplements were able to lower counts of EHEC along the gut. Supplementing scFOS was mostly associated with changes in the gut ecosystem and increases in the lactobacilli population, while S. cerevisiae Sc 47 registered increases in the numbers of ileal intraepithelial lymphocytes. The synbiotic mixture showed the lowest diarrhea incidence and fecal scores, benefiting from complementary modes of action and possible synergistic effects due to a hypothesized yeast-LAB cross-feeding phenomenon in the foregut. In conclusion, our results evidence that supplementing scFOS or Saccharomyces cerevisiae Sc 47 is efficacious to fight post-weaning colibacillosis, and combining both could be beneficial in high-risk scenarios.

Gastrointestinal dynamics, immune response, and nutrient digestibility of weanling pigs fed diets supplemented with enzymatically treated yeast1

The objective of this trial was to investigate the effect of enzymatically treated yeast (ETY) on the growth performance, nutrient digestibility, immune response, and gut health of weanling pigs. A total of 192 weanling pigs (6.0 ± 1.04 kg) were allocated to 4 corn and soybean-based diets with increasing concentrations of ETY (0, 1, 2, or 4 g/kg) for a 43-d trial. There were 8 replicate pens (4 replicate pens per sex) and 6 pigs per replicate. The experiment was set up as a randomized complete block design with body weight used as a blocking factor. Pigs had ad libitum access to water and diets for the duration of the study. There was no effect of ETY supplementation on the growth performance indices of weanling pigs. At day 14, there was a quadratic decrease (P < 0.05) in the apparent total tract digestibility (ATTD) of acid detergent fiber (ADF). At day 28, there was a linear increase (P < 0.05) in the ATTD of neutral detergent fiber and a quadratic decrease (P < 0.05) in the ATTD of ADF. On day 14, there was a linear increase (P < 0.05) in serum catalase activity with ETY supplementation. There was a linear increase (P < 0.01) in the gene expression of glutathione peroxidase-4 in the ileal mucosa of pigs. Increasing dietary ETY supplementation linearly decreased (P < 0.05) the gene expression of ileal peptide transporter 1. There was a tendency for a quadratic effect (P = 0.07) in the ileal villus height to crypt depth ratio with ETY supplementation. In addition, there was a tendency for a linear increase (P = 0.06) in ileal digesta butyrate with ETY supplementation. In conclusion, the current study demonstrated that dietary ETY supplementation could partly ameliorate the deleterious effects of post-weaning stress by enhancing the antioxidative status of weanling pigs. However, prolonged supplementation of ETY may be needed to see its effect on growth performance.

Review on Preventive Measures to Reduce Post-Weaning Diarrhoea in Piglets

In many countries, medical levels of zinc (typically as zinc oxide) are added to piglet diets in the first two weeks post-weaning to prevent the development of post-weaning diarrhoea (PWD). However, high levels of zinc constitute an environmental polluting agent, and may contribute to the development and/or maintenance of antimicrobial resistance (AMR) among bacteria. Consequently, the EU banned administering medical levels of zinc in pig diets as of June 2022. However, this may result in an increased use of antibiotic therapeutics to combat PWD and thereby an increased risk of further AMR development. The search for alternative measures against PWD with a minimum use of antibiotics and in the absence of medical levels of zinc has therefore been intensified over recent years, and feed-related measures, including feed ingredients, feed additives, and feeding strategies, are being intensively investigated. Furthermore, management strategies have been developed and are undoubtedly relevant; however, these will not be addressed in this review. Here, feed measures (and vaccines) are addressed, these being probiotics, prebiotics, synbiotics, postbiotics, proteobiotics, plants and plant extracts (in particular essential oils and tannins), macroalgae (particularly macroalgae-derived polysaccharides), dietary fibre, antimicrobial peptides, specific amino acids, dietary fatty acids, milk replacers, milk components, creep feed, vaccines, bacteriophages, and single-domain antibodies (nanobodies). The list covers measures with a rather long history and others that require significant development before their eventual use can be extended. To assess the potential of feed-related measures in combating PWD, the literature reviewed here has focused on studies reporting parameters of PWD (i.e., faeces score and/or faeces dry matter content during the first two weeks post-weaning). Although the impact on PWD (or related parameters) of the investigated measures may often be inconsistent, many studies do report positive effects. However, several studies have shown that control pigs do not suffer from diarrhoea, making it difficult to evaluate the biological and practical relevance of these improvements. From the reviewed literature, it is not possible to rank the efficacy of the various measures, and the efficacy most probably depends on a range of factors related to animal genetics and health status, additive doses used, composition of the feed, etc. We conclude that a combination of various measures is probably most recommendable in most situations. However, in this respect, it should be considered that combining strategies may lead to additive (e.g., synbiotics), synergistic (e.g., plant materials), or antagonistic (e.g., algae compounds) effects, requiring detailed knowledge on the modes of action in order to design effective strategies.

Mulberry leaf meal: A potential feed supplement for juvenile Megalobrama amblycephala "Huahai No. 1"

This study was performed to evaluate the potential application of mulberry leaf meal (ML) and fermented mulberry leaf meal (FML) as feed supplements in aquatic animals for developing varieties of practical and economical feed ingredients. Juveniles Megalobrama amblycephala were fed a basal diet (35.7% crude protein, 10.4% crude lipid; control group) supplemented with 2.22% and 4.44% mulberry leaf meals (ML2, ML4) and fermented mulberry leaf meals (FML2, FML4) for 8 weeks. Generally, the two-way ANOVA showed the supplementation level exhibited a prominent effect on the growth performance and physiological status of fish. Furthermore, the two-way ANOVA showed the supplementary fermented mulberry leaf meal increased plasma complement 4 (C4) content (P < 0.05). The weight gain rate (WGR, 145.87%) and the specific growth rate (SGR, 1.63%) were significantly increased in FML2 group compared with the control group (P < 0.05). The muscle crude lipid content and hepatosomatic index (HSI) were higher in FML2 group than that in ML2 group (P < 0.05). The hepatic GSH content in ML4 group and CAT, T-SOD activities in FML4 group were significantly increased compared with the control group (P < 0.05). The hepatic MDA content in FML4 group was significantly decreased compared with the FML2 group (P < 0.05). Total cholesterol (TC) contents showed a significant decrease in ML4 and FML4 groups compared with the control group (P < 0.05). Regarding the gene expression, sirtiun 1 (Sirt1) gene expression was elevated in FML2 group compared with the ML2 group (P < 0.05). Compare to the control group, FML2 diet significantly increased the expression of i-kappa-B alpha (IKBα) gene in liver, and decreased the expression of forkhead box O1 α (FoxO1α), toll-like receptors 4 (TLR4) and nuclear factor-kappa B (NF-κB) genes (P < 0.05). In conclusion, 2.22% FML promoted the growth performance of M. amblycephala and enhanced the anti-inflammatory responses by inhibiting TLR4/NF-κB signaling pathway. On the other hand, 4.44% FML reduced plasma lipid content (hypolipedemic effect) and improved the hepatic antioxidant capacity of M. amblycephala.

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.

Effects of supplementation with Saccharomyces cerevisiae products on dairy calves: A meta-analysis

Saccharomyces cerevisiae products (SCP) have the potential to promote the growth and development of the gastrointestinal tract and immunity in young livestock animals. However, the effects of SCP supplementation on calves are inconsistent among the reported studies in the literature. Hence, we performed a meta-analysis to comprehensively assess the effects of SCP on the growth performance, ruminal fermentation parameters, nutrients digestibility, ruminal histological morphology, serum immune response, and fecal pathogen colony counts in calves. We searched the Web of Science, ScienceDirect, PubMed, and China National Knowledge Infrastructure for relevant studies published up to October 1, 2021. After screening against a set of criteria, the data of 36 studies were included in our meta-analysis (2,126 calves in total). We evaluated the quality of the data using sensitivity analysis and assessed publication bias. Our meta-analysis revealed several important findings. First, SCP supplementation increased the ruminal short-chain fatty acid concentration, ruminal papilla height, and fiber digestibility, pointing toward stimulation of the development of the rumen in calves. Second, SCP supplementation increased the serum concentrations of total protein, IgA, and IgG but decreased fecal pathogen colony counts, suggesting that SCP could help calves to promote immunity (especially maintaining circulating concentrations of immunoglobulins in preweaning calves) and resistance to pathogens. Third, a subgroup analysis between preweaning and postweaning calves showed that SCP increased average daily gain and dry matter intake preweaning but not postweaning, suggesting that SCP is better supplemented to preweaning calves to achieve the best results. Forth, based on the dose-response curve, 24 to 25 g/d might be the optimal dose range of SCP supplementation (into starter feed) preweaning to achieve the best overall effect, meanwhile, we need more studies to improve the consistency and accuracy of the dose-response curve prediction. Overall, SCP supplementation improved growth performance, rumen development, and immunocompetence in calves, particularly in preweaning calves.

The Role of Probiotics in Alleviating Postweaning Diarrhea in Piglets From the Perspective of Intestinal Barriers

Early weaning of piglets is an important strategy for improving the production efficiency of sows in modern intensive farming systems. However, due to multiple stressors such as physiological, environmental and social challenges, postweaning syndrome in piglets often occurs during early weaning period, and postweaning diarrhea (PWD) is a serious threat to piglet health, resulting in high mortality. Early weaning disrupts the intestinal barrier function of piglets, disturbs the homeostasis of gut microbiota, and destroys the intestinal chemical, mechanical and immunological barriers, which is one of the main causes of PWD in piglets. The traditional method of preventing PWD is to supplement piglet diet with antibiotics. However, the long-term overuse of antibiotics led to bacterial resistance, and antibiotics residues in animal products, threatening human health while causing dysbiosis of gut microbiota and superinfection of piglets. Antibiotic supplementation in livestock diets is prohibited in many countries and regions. Regarding this context, finding antibiotic alternatives to maintain piglet health at the critical weaning period becomes a real emergency. More and more studies showed that probiotics can prevent and treat PWD by regulating the intestinal barriers in recent years. Here, we review the research status of PWD-preventing and treating probiotics and discuss its potential mechanisms from the perspective of intestinal barriers (the intestinal microbial barrier, the intestinal chemical barrier, the intestinal mechanical barrier and the intestinal immunological barrier) in piglets.

Influence of yeast-based pre- and probiotics in lactation and nursery diets on nursery pig performance and antimicrobial resistance of fecal Escherichia coli

Two experiments were conducted to determine the impact of various combinations of yeast-based direct fed microbials (DFM) in diets fed to nursery pigs weaned from sows fed lactation diets with or without yeast additives. In Exp. 1, 340 weaned pigs, initially 5.1 kg ± 0.02, were used to evaluate previous sow treatment (control vs yeast additives) and nursery diets with or without added yeast-based DFM on growth performance and antimicrobial resistance (AMR) patterns of fecal Escherichia coli. Treatments were arranged in a 2 × 2 factorial with main effects of sow treatment (control vs. yeast-based pre- and probiotic diet; 0.10% ActiSaf Sc 47 HR+ and 0.025% SafMannan, Phileo by Lesaffre, Milwaukee, WI) and nursery treatment (control vs. yeast-based pre- and probiotic diet; 0.10% ActiSaf Sc 47 HR+, 0.05% SafMannan, and 0.05% NucleoSaf from d 0 to 7, then concentrations were decreased by 50% from d 7 to 24) with 5 pigs per pen and 17 replications per treatment. Progeny from sows fed yeast additives had increased (P < 0.05) average daily gain (ADG) from d 0 to 24 and d 0 to 45. However, pigs that were fed yeast additives for the first 24 d in the nursery tended to have decreased d 0 to 45 ADG (P = 0.079). Fecal E. coli isolated from pigs from the sows fed yeast group had increased (P = 0.034) resistance to nalidixic acid and a tendency for increased resistance to ciprofloxacin (P = 0.065) and gentamicin (P = 0.054). Yet, when yeast additives were added in the nursery there was reduced (P < 0.05) fecal E. coli resistance to azithromycin and chloramphenicol. In Exp. 2, 330 weaned pigs, initially 5.8 kg ± 0.03, were used to evaluate diets with two different combinations of DFM on growth performance. Treatments were arranged in a 2 × 3 factorial with main effects of sow treatment (same as described in Exp. 1) and nursery treatment (control; YCW, 0.05% of SafMannan from d 0 to 38 and NucleoSaf at 0.05% from d 0 to 10 and 0.025% from d 10 to 24; or DFM, 0.10% MicroSaf-S from d 0 to 38 and NucleoSaf at 0.05% from d 0 to 10 and 0.025% from d 10 to 24) with 6 pigs per pen and 8 to 10 replications per treatment. From d 0 to 10 post-weaning, progeny of sows fed yeast additives had increased (P < 0.05) ADG and G:F. In conclusion, feeding sows yeast through lactation improved offspring growth performance in the nursery. While feeding live yeast and yeast extracts reduced nursery pig performance in Exp. 1, feeding DFM improved growth later in the nursery period in Exp. 2.

Growth performance, immune status, gastrointestinal tract ecology and function in nursery pigs fed enzymatically treated yeast without or with pharmacological levels of zinc

Growth performance and physiological responses of nursery piglets when fed enzymatically treated yeast (HY40) and pharmacological ZnO alone or in combination, were investigated. A total of 144 pigs (21d old, BW 7.32±0.55 kg) were placed in 36 pens (4 pigs/pen). Pigs were randomly assigned to one of four dietary treatments (n=9): [1] control corn-wheat-soybean meal diet (control), [2] control + HY40 (HY40), [3] control +ZnO and [4] control + HY40 + ZnO (HY40+ZnO). Inclusion of HY40 and ZnO was 0.5% and 3,000 ppm in phase I (d 0 to 14), respectively, and halved in phase II (d 15 to 42). All diets contained 0.2% TiO2 for determination of apparent total tract digestibility (ATTD) of components. Body weight and feed disappearance was recorded weekly. One pig per pen was sacrificed for organ weights, blood, and tissue samples on d 14. Except for phase II, when HY40+ZnO pigs had greater average daily feed intake (P=0.004) than all other treatments, there were no (P>0.05) interactions between HY40 and ZnO on growth performance. Pigs fed HY40 or ZnO containing diets were heavier (P<0.05) than pigs fed without by the end of the study. On d 14, pigs fed additives exhibited higher (P≤0.009) ATTD of dry matter (DM) and gross energy (GE) than control pigs. On d 28, pigs fed control, HY40 and HY40+ZnO had greater (P≤0.022) ATTD of DM, crude protein, and GE than piglets fed ZnO only. Pigs fed HY40+ZnO had lower ileal digesta E. coli concentration (P<0.05) than HY40 and control pigs. Ileal digesta of pigs fed ZnO diets had higher lactobacillus to E. coli ratio (1.44 vs. 1.20; P=0.001), exhibited higher concentrations of acetic (P=0.01) and butyric acid (P=0.01) but lower lactic (P=0.02) and total short chain fatty acids (P=0.033) than pigs fed non-ZnO diets. Greater (P<0.05) mRNA expression of nutrient transporters, tight junction proteins and fecal excretion of zinc (Zn) was observed in ZnO pigs relative to non-ZnO pigs. Pigs fed HY40 diets had greater (P=0.002) villus height to crypt depth ratio (VH:CD) than non-HY40 pigs. The concentration of plasma IgA was higher (P=0.04) in HY40+ZnO pigs relative to other pigs whereas HY40 pigs showed higher (P<0.001) jejunal IgA than non-HY40 pigs. Although the mode of action of HY40 and ZnO differed, the present study indicated that HY40 improved growth performance and jejunal function and immunity, making HY40 an effective alternative to pharmacological ZnO for nursery pigs.

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.

Dietary supplementation of fructooligosaccharides alleviates enterotoxigenic E. coli-induced disruption of intestinal epithelium in a weaned piglet model

Diarrhea caused by pathogens such as enterotoxigenic E. coli (ETEC) is a serious threat to the health of young animals and human infants. Here, we investigated the protective effect of fructooligosaccharides (FOS) on the intestinal epithelium with ETEC-challenge in a weaned piglet model. Twenty-four weaned piglets were randomly divided into three groups: (1) non-ETEC-challenged control (CON), (2) ETEC-challenged control (ECON), and (3) ETEC challenge + 2.5 g/kg FOS (EFOS). On day 19, the CON pigs were orally infused with sterile culture, while the ECON and EFOS pigs were orally infused with active ETEC (2.5 × 109 colony-forming units). On day 21, pigs were slaughtered to collect venous blood and small intestine. Result showed that the pre-treatment of FOS improved the antioxidant capacity and the integrity of intestinal barrier in the ETEC-challenged pigs without affecting their growth performance. Specifically, comparing with ECON pigs, the level of GSH-Px (glutathione peroxidase) and CAT (catalase) in the plasma and intestinal mucosa of EFOS pigs was increased (P<0.05), and the intestinal barrier marked by ZO-1 and plasmatic DAO was also improved in EFOS pigs. A lower level (P<0.05) of inflammatory cytokines in the intestinal mucosa of EFOS pigs might be involved in the inhibition of TLR4/MYD88/NF-κB pathway. The apoptosis of jejunal cells in EFOS pigs was also lower than that in ECON pigs (P<0.05). Our findings provide convincing evidence of possible prebiotic and protective effect of FOS on the maintenance of intestinal epithelial function under the attack of pathogens.

Live yeast and yeast extracts with and without pharmacological levels of zinc on nursery pig growth performance and antimicrobial susceptibilities of fecal Escherichia coli

A total of 360 weanling barrows (Line 200 ×400, DNA, Columbus NE; initially 5.6 ± 0.03 kg) were used in a 42-d study to evaluate yeast-based pre- and probiotics (Phileo by Lesaffre, Milwaukee, WI) in diets with or without pharmacological levels of Zn on growth performance and antimicrobial resistance (AMR) patterns of fecal Escherichia coli. Pens were assigned to 1 of 4 dietary treatments with 5 pigs per pen and 18 pens per treatment. Dietary treatments were arranged in a 2 × 2 factorial with main effects of yeast-based pre- and probiotics (none vs. 0.10% ActiSaf Sc 47 HR+, 0.05% SafMannan, and 0.05% NucleoSaf from d 0 to 7, then concentrations were lowered by 50% from d 7 to 21) and pharmacological levels of Zn (110 vs. 3,000 mg/kg from d 0 to 7, and 2,000 mg/kg from d 7 to 21 with added Zn provided by ZnO). All pigs were fed a common diet from d 21 to 42 post-weaning. There were no yeast ×Zn interactions or effects from yeast additives observed on any response criteria. From d 0 to 21, and 0 to 42, pigs fed pharmacological levels of Zn had increased (P < 0.001) ADG and ADFI. Fecal samples were collected on d 4, 21, and 42 from the same three pigs per pen for fecal dry matter (DM) and AMR patterns of E. coli. On d 4, pigs fed pharmacological levels of Zn had greater fecal DM (P = 0.043); however, no differences were observed on d 21 or 42. E. coli was isolated from fecal samples and the microbroth dilution method was used to determine the minimal inhibitory concentrations (MIC) of E. coli isolates to 14 different antimicrobials. Isolates were categorized as either susceptible, intermediate, or resistant based on Clinical and Laboratory Standards Institute (CLSI) guidelines. The addition of pharmacological levels of Zn had a tendency (P = 0.051) to increase the MIC values of ciprofloxacin; however, these MIC values were still well under the CLSI classified resistant breakpoint for Ciprofloxacin. There was no evidence for differences (P > 0.10) for yeast additives or Zn for AMR of fecal E. coli isolates to any of the remaining antibiotics. In conclusion, pharmacological levels of Zn improved ADG, ADFI, and all isolates were classified as susceptible to ciprofloxacin although the MIC of fecal E. coli tended to be increased. Thus, the short-term use of pharmacological levels of Zn did not increase antimicrobial resistance. There was no response observed from live yeast and yeast extracts for any of the growth, fecal DM, or AMR of fecal E. coli criteria.

Effects of Different Fermented Feeds on Production Performance, Cecal Microorganisms, and Intestinal Immunity of Laying Hens

Simple Summary

Fermented feed exerts beneficial effects on intestinal microorganisms, host health, and production performance. However, the effect of fermented feed on laying hens is uncertain due to the different types of inoculated probiotics, fermentation substrates, and fermentation technology. Hence, this experiment was conducted to investigate the effects of fermented feed with different compound strains on the performance and intestinal health of laying hens. Supplement fermented feed reduced the feed conversion ratio and promoted egg quality. Both dietary treatment (fermented feed A produced Bacillus subtilis, Lactobacillus, and Yeast and fermented feed B produced by C. butyricum and L. salivarius) influenced intestinal immunity and regulated cecal microbial structure. This may be because the metabolites of microorganisms in fermented feed and the reduced pH value inhibited the colonization of harmful bacteria, improved the intestinal morphology, and then had a positive impact on the production performance and albumen quality of laying hens.

Abstract

This experiment was conducted to investigate the effects of different compound probiotics on the performance, cecal microflora, and intestinal immunity of laying hens. A total of 270 Jing Fen No.6 (22-week-old) were randomly divided into 3 groups: basal diet (CON); basal diet supplemented with 6% fermented feed A by Bacillussubtilis,Lactobacillus, and Yeast (FA); and with 6% fermented feed B by C. butyricum and L. salivarius (FB). Phytic acid, trypsin inhibitor, β-glucan concentrations, and pH value in fermented feed were lower than the CON group (p < 0.05). The feed conversion ratio (FCR) in the experimental groups was decreased, while albumen height and Haugh unit were increased, compared with the CON group (p < 0.05). Fermented feed could upregulate the expression of the signal pathway (TLR4/MyD88/NF-κB) to inhibit mRNA expression of pro-inflammatory cytokines (p < 0.05). Fermented feed promoted the level of Romboutsia (in the FA group) Butyricicoccus (in the FB group), and other beneficial bacteria, and reduced opportunistic pathogens, such as Enterocooccus (p < 0.05). Spearman’s correlations showed that the above bacteria were closely related to albumen height and intestinal immunity. In summary, fermented feed can decrease the feed conversion ratio, and improve the performance and intestinal immunity of laying hens, which may be related to the improvement of the cecal microflora structure.

Impact of yeast hydrolysate (Saccharomyces cerevisiae) supplementation on the growth performance, nutrient digestibility, fecal microflora, noxious gas emission, blood profile, and meat quality of finishing pigs

A total of 90 finishing pigs (52 ± 1.46 kg) were randomly assigned to one of three dietary treatments as: TRT1 [CON (basal diet)], TRT2 [CON + 0.05% yeast hydrolysate (YH)], and TRT3 (CON + 0.1% YH) for an 8 wk trial. Each treatment had six replications and five (three gilts and two barrow) pigs per pen. In weeks 4 and 8, YH supplement linearly increased (P < 0.05) body weight. Moreover, average daily gain was also linearly increased (P < 0.05) with YH supplementation in week 4 and the overall trial period. At the end of the trial, apparent total tract digestibility of dry matter, nitrogen, and gross energy was linearly increased in pigs fed YH supplementation. In addition, fecal Lactobacillus counts, insulin-like growth factor 1 (IGF-1) concentration, and the lean meat percentage were linearly increased by YH supplementation. Also, YH supplementation elicited a linear reduction on drip loss during days 3, 5, and 7. In summary, dietary yeast hydrolysate supplement positively enhanced the growth performance, nutrient digestibility, Lactobacillus count and reduced the drip loss traits of finishing pig. Thus, we infer that the application of 0.1% S. cerevisiae YH can enhance the growth efficiency of finishing pigs.

Porcine enterotoxigenic Escherichia coli: Antimicrobial resistance and development of microbial-based alternative control strategies

Strains of enterotoxigenic Escherichia coli (ETEC) causing post-weaning diarrhoea (PWD) in piglets have a widespread and detrimental impact on animal health and the economics of pork production. Traditional approaches to control and prevention have placed a strong emphasis on antimicrobial use (AMU) to the extent that current prevalent porcine ETEC strains have developed moderate to severe resistance. This complicates treatment of ETEC infection by limiting therapeutic options, increasing diagnostic costs and increasing mortality rates. Management factors, the use of supra-physiological levels of zinc oxide and selected feed additives have all been documented to lower the incidence of ETEC infection in pigs; however, each intervention has its own limitations and cannot solely be relied upon as an alternative to AMU. Consequently, treatment options for porcine ETEC are moving towards the use of newer antimicrobials of higher public health significance. This review focuses on microorganisms and microbial-derived products that could provide a naturally evolved solution to ETEC infection and disease. This category holds a plethora of yet to be explored possibilities, however studies based around bacteriophage therapy, probiotics and the use of probiotic fermentation products as postbiotics have demonstrated promise. Ultimately, pig producers and veterinarians need these solutions to reduce the reliance on critically important antimicrobials (CIAs), to improve economic and animal welfare outcomes, and to lessen the One Health threat potentiated by the dissemination of AMR through the food chain.

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.

Benzoic Acid Combined with Essential Oils Can Be an Alternative to the Use of Antibiotic Growth Promoters for Piglets Challenged with E. coli F4

Simple Summary

The use of antibiotics as growth promoters for swine must be minimized as it can promote resistance in microorganisms. Therefore, it is essential to search for alternative additives. This study aimed to investigate the effects of benzoic acid and a blend of essential oils (thymol, 2-methoxyphenol, eugenol, piperine, and curcumin) on the performance and intestinal health of weanling piglets challenged with Escherichia coli F4. The combination of benzoic acid and essential oils at 3 g/kg improved the piglets’ average daily gain and consequently their final body weight and it is an economically viable alternative to replace colistin. These results could have a great impact on society, contributing to the one heath concept and demonstrating the ability to replace antibiotics as growth promoters and thus minimize the chance of causing bacteria resistance.

Abstract

Benzoic acid (BA) and essential oils (EOs) (thymol, 2-methoxyphenol, eugenol, piperine, and curcumin) are being studied to minimize the impairment of gastrointestinal functions in weanling piglets. This study evaluates the effects of combining BA and EO on the performance and intestinal health of piglets challenged with E. coli F4 (1 mL, 10⁶ CFU/mL). In total, 270 weaned piglets were used in a randomized block design with six treatments: positive control, with 40 mg/kg colistin (PC); negative control, without the growth promoter (NC); negative control +5 g/kg benzoic acid (BA); negative control +2 g/kg combination of BA+EO (BA+EO2); negative control +3 g/kg combination of BA+EO (BA+EO3); negative control +4 g/kg combination of BA+EO (BA+EO4). BA+EO3 presented a greater average daily gain (ADG) (p = 0.0013) and better feed-to-gain ratio (p = 0.0138), compared to NC, from 21 to 35 days age. For the total period, BA, BA+EO3, and BA+EO4 were similar to PC and superior to NC for ADG (p = 0.0002) and final body weight (BW) (p = 0.0002). No difference (p > 0.05) was verified for diarrhea, microbial population, production of volatile fatty acids, pH, weight of organs, cellular proliferation, and cholecystokinin count. NC and BA+EO4 resulted in a higher villus height in the jejunum (p = 0.0120) compared to BA+EO3. The use of BA or the combination of BA and EO at 3 g/kg provides improved performance, aside from being an economically viable alternative to replace colistin.

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.

Bacillus subtilis and Enterococcus faecium co-fermented feed regulates lactating sow's performance, immune status and gut microbiota

Fermented feed (FF) is widely applied to improve swine performance. However, the understandings of the effects of FF on the immune status and gut microbiota of lactating sows and whether probiotics are the effective composition of FF are still limited. The present study aimed to investigate the performance, immune status and gut microbiota of lactating sows fed with a basal diet supplemented with Bacillus subtilis and Enterococcus faecium co-fermented feed (FF), with the probiotic combination (PRO) of B. subtilis and E. faecium and control diet (CON) as controls. Compared with the CON group, FF group remarkably improved the average daily feed intake of sows and the weight gain of piglets, while significantly decreased the backfat loss, constipation rate of sows and diarrhoea incidence of piglets. The yield and quality of milk of sows in FF group were improved. Besides, faecal acetate and butyrate were promoted in FF group. Additionally, FF increased the level of IgG, IgM and IL-10 and decreased the concentration of TNF-α in serum. Furthermore, FF reduced the abundance of Enterobacteriaceae and increased the level of Lactobacillus and Succiniclasticum, which were remarkably associated with growth performance and serum immune parameters. Accordingly, microbial metabolic functions including DNA repair and recombination proteins, glycolysis and gluconeogenesis, mismatch repair and d-alanine metabolism were significantly upregulated, while amino acid metabolism was downregulated in FF group. Overall, the beneficial effects of FF were superior to PRO treatment. Altogether, administration of FF during lactation improved the performance and immune status, and modulated gut microbiota of sows. Probiotics are not the only one effective compound of FF.

Fermented Feed Modulates Meat Quality and Promotes the Growth of Longissimus Thoracis of Late-Finishing Pigs

This study investigated the effect of fermented diet on growth performance, carcass traits, meat quality and growth of longissimus thoracis (LT) of finishing pigs. A total of 48 finishing pigs [Duroc × (Landrace × Large White), male, 126 ± 5-d-old] weighing 98.76 ± 1.27 kg were randomly assigned to two treatments (eight pens per treatment and three pigs per pen) for a 28-d feeding trial, including control diet and fermented diet. Fermented diet significantly increased the loin eye area and lean mass percentage, decreased backfat thickness and improved meat quality of LT by decreasing the shear force and drip loss at 48 h post slaughter and improving meat sensory characteristics compared with control diet. A fermented diet also significantly increased the abundance of insulin, insulin receptor (IR), myoblast determination protein (MyoD) and myosin heavy chain-I (MyHC-I) transcripts, and the phosphorylation levels of AKT, mTORC1, 4EBP1 and S6K1 in LT, while decreasing the expression of muscle atrophy F-box (MAFbx) and forkhead Box O1 (Foxo1) mRNA transcripts. Moreover, proteomic analysis revealed that differentially expressed proteins predominantly involved in protein synthesis and muscle development were modulated by fermented diet. Our results indicated that a fermented diet improved meat quality and enhanced LT growth of finishing pigs by increasing insulin/AKT/mTORC1 protein synthesis cascade and activating the Foxo1/MAFbx pathway, along with the regulation of ribosomal protein and proteins involved in muscle contraction and muscle hypertrophy.

Growth performance and gut health of Escherichia coli-challenged weaned pigs fed diets supplemented with a Bacillus subtilis direct-fed microbial

This study was conducted to investigate the effects of a direct-fed microbial (DFM) product (Bacillus subtilis strain DSM 32540) in weaned pigs challenged with K88 strain of Escherichia coli on growth performance and indicators of gut health. A total of 21 weaned pigs [initial body weight (BW) = 8.19 kg] were housed individually in pens and fed three diets (seven replicates per diet) for 21 d in a completely randomized design. The three diets were a corn-soybean meal-based basal diet without feed additives, a basal diet with 0.25% antibiotics (neo-Oxy 10-10; neomycin + oxytetracycline), or a basal diet with 0.05% DFM. All pigs were orally challenged with a subclinical dose (6.7 × 10⁸ CFU/mL) of K88 strain of E. coli on day 3 of the study (3 d after weaning). Feed intake and BW data were collected on days 0, 3, 7, 14, and 21. Fecal scores were recorded daily. On day 21, pigs were sacrificed to determine various indicators of gut health. Supplementation of the basal diet with antibiotics or DFM did not affect the overall (days 0-21) growth performance of pigs. However, antibiotics or DFM supplementation increased (P = 0.010) gain:feed (G:F) of pigs during the post-E. coli challenge period (days 3-21) by 23% and 24%, respectively. The G:F for the DFM-supplemented diet did not differ from that for the antibiotics-supplemented diet. The frequency of diarrhea for pigs fed a diet with antibiotics or DFM tended to be lower (P = 0.071) than that of pigs fed the basal diet. The jejunal villous height (VH) and the VH to crypt depth ratio (VH:CD) were increased (P < 0.001) by 33% and 35%, respectively, due to the inclusion of antibiotics in the basal diet and by 43% and 41%, respectively due to the inclusion of DFM in the basal diet. The VH and VH:CD for the DFM-supplemented diet were greater (P < 0.05) than those for the antibiotics-supplemented diet. Ileal VH was increased (P < 0.05) by 46% due to the inclusion of DFM in the basal diet. The empty weight of small intestine, cecum, or colon relative to live BW was unaffected by dietary antibiotics or DFM supplementation. In conclusion, the addition of DFM to the basal diet improved the feed efficiency of E. coli-challenged weaned pigs to a value similar to that of the antibiotics-supplemented diet and increased jejunal VH and VH:CD ratio to values greater than those for the antibiotics-supplemented diet. Thus, under E. coli challenge, the test DFM product may replace the use of antibiotics as a growth promoter in diets for weaned pigs to improve feed efficiency and gut integrity.

Growth performance, organ weight, fecal scores, plasma, and ceca digesta microbial metabolites in growing pigs fed spent biomass of Pichia kudriavzevii

Growth performance, liver and spleen weight, plasma, and ceca digesta metabolites and incidences of diarrhea were investigated in growing pigs fed spent biomass of Pichia kudriavzevii. Ninety six barrows (~25 kg, 4 pigs/pen) were fed 1 of 4 experimental diets (n = 6) for 7 weeks. The diets were control, corn-, and soybean meal-based diet or control plus 2.5%, 3.75%, or 5.0% P. kudriavzevii. Diets were formulated to be isocaloric and iso nitrogenous. Feed intake and body weight (BW) were recorded weekly for calculation of average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G:F). Fecal scores were taken 3 d/wk to assess incidence and severity of diarrhea. One pig/pen close to pen average was bled for plasma metabolites on days 7 and 49 and subsequently euthanized for spleen and liver weight, ileal and cecum digesta samples for concentration of short-chain fatty acids (SCFA). The concentration of crude protein, crude fat, and non-fiber carbohydrates in P. kudriavzevii biomass was 36.4%, 9.6%, and 50.8% DM, respectively. Inclusion of P. kudriavzevii tended (P = 0.06) to linearly reduce ADG from days 8 through 49 resulting in a trend (P = 0.06) for linear reduction in the final BW. The final BW was 79.0, 79.2, 76.8, and 75.5 kg for the 0%, 2.5%, 3.75%, and 5.0% P. kudriavzevii, respectively. Diets had no effect (P > 0.10) on ADFI, G:F, spleen, and liver weight throughout the entire experiment. On day 7, there was cubic (P = 0.03) decrease and quadratic (P = 0.02) increase in plasma concentration of creatinine and urea N, respectively. However, there were no (P > 0.10) diet effects on plasma metabolites on day 49. There was a tendency (P = 0.08) for linear increase in cecum digesta concentration of acetic acid. There were no diet effects (P > 0.10) on fecal score in the first 4 wk of feeding. In conclusion, feeding P. kudriavzevii yeast tended to depress growth and stimulate cecum fermentation at higher dose and had no detrimental effects on organ weights or plasma metabolites in growing pigs.

Innate Immunomodulation in Food Animals: Evidence for Trained Immunity?

Antimicrobial resistance (AMR) is a significant problem in health care, animal health, and food safety. To limit AMR, there is a need for alternatives to antibiotics to enhance disease resistance and support judicious antibiotic usage in animals and humans. Immunomodulation is a promising strategy to enhance disease resistance without antibiotics in food animals. One rapidly evolving field of immunomodulation is innate memory in which innate immune cells undergo epigenetic changes of chromatin remodeling and metabolic reprogramming upon a priming event that results in either enhanced or suppressed responsiveness to secondary stimuli (training or tolerance, respectively). Exposure to live agents such as bacille Calmette-Guerin (BCG) or microbe-derived products such as LPS or yeast cell wall ß-glucans can reprogram or "train" the innate immune system. Over the last decade, significant advancements increased our understanding of innate training in humans and rodent models, and strategies are being developed to specifically target or regulate innate memory. In veterinary species, the concept of enhancing the innate immune system is not new; however, there are few available studies which have purposefully investigated innate training as it has been defined in human literature. The development of targeted approaches to engage innate training in food animals, with the practical goal of enhancing the capacity to limit disease without the use of antibiotics, is an area which deserves attention. In this review, we provide an overview of innate immunomodulation and memory, and the mechanisms which regulate this long-term functional reprogramming in other animals (e.g., humans, rodents). We focus on studies describing innate training, or similar phenomenon (often referred to as heterologous or non-specific protection), in cattle, sheep, goats, swine, poultry, and fish species; and discuss the potential benefits and shortcomings of engaging innate training for enhancing disease resistance.

Isoleucine attenuates infection induced by E. coli challenge through the modulation of intestinal endogenous antimicrobial peptide expression and the inhibition of the increase in plasma endotoxin and IL-6 in weaned pigs

Enteric infection is a major cause of morbidity and mortality in both humans and animals worldwide. Immunotherapy against intestinal infection is a well-known alternative to the antibiotic strategy. Herein, we demonstrated that isoleucine significantly suppressed the multiplication of E. coli in the presence of IPEC-J2 cells. Isoleucine supplementation enhanced the concentrations of total plasma protein and IgA in pigs compared to the alanine control diet, while inhibiting the increase in plasma endotoxin and IL-6 contents induced by E. coli challenge. A significant interaction between the E. coli challenge and the diet treatment was found in the red blood cell volume. Isoleucine improved the expression of porcine β-defensin-1 (pBD-1), pBD-2, pBD-3, pBD-114 and pBD-129 in the jejunum and ileum of pigs with or without E. coli challenge. Conclusively, isoleucine attenuated the infection caused by the E. coli challenge possibly through increasing the intestinal β-defensin expression and inhibiting the increase in plasma endotoxin and IL-6 in weaned pigs.

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.

Immune Response of Piglets Receiving Mixture of Formic and Propionic Acid Alone or with Either Capric Acid or Bacillus Licheniformis after Escherichia coli Challenge

This study aims to evaluate whether diets containing mixture of formic and propionic acid alone or supplemented with either capric acid or Bacillus Licheniformis can alleviate immune inflammatory response of piglets challenged with enterotoxigenic Escherichia coli (ETEC). A total of 30 weaning pigs were assigned to 5 diets, without additive (CON), with antibiotics (ATB), with 1% organic acid (OA; 64% formic and 25% propionic acid), with OA plus 0.2% capric acid (OA + CRA), and with OA plus 0.02% probiotic (Bacillus Licheniformis; OA + PB). After oral challenge with ETEC on day 10, the feces and plasma of all pigs were collected at different time points. Four additive treatments all decreased rectal temperature (RT) at 9 h and fecal scores (FS) at 24 h after challenge (P < 0.05), while at 9 h after challenge, inclusion of OA induced a decrease of RT compared with OA + CRA and OA + PB (P < 0.05). In plasma, concentration of interleukin (IL)-1β was reduced with the addition of ATB and OA at 24 h and 48 h after challenge and it is lower in OA group than OA + CRA group at 24 h after challenge (P < 0.05). Diets with ATB, OA, and OA + PB caused a decrease of the concentrations of IL-6 in plasma at 9 h after challenge (P < 0.05). The four additives treated piglets showed decreased concentrations of plasma tumor necrosis factor-α and interferon-γ at 9 h and 24 h after challenge, respectively (P < 0.05). In conclusion, OA supplementation alleviated the inflammatory response and reduced diarrhea incidence in piglets challenged with ETEC. However, no further improvements were observed when OA supplemented with CRA or probiotics.

Effects of dietary lysozyme levels on growth performance, intestinal morphology, immunity response and microbiota community of growing pigs

BACKGROUND

Lysozyme has been studied as a potential alternative to antibiotics for animals in recent years. The aim of this study was to evaluate the effect of dietary lysozyme on growth performance, serum biochemical parameters, immune response and gut health of growing pigs.

RESULTS

A total of 216 growing pigs (19.81 ± 0.47 kg) were fed the diets supplemented with colistin sulfate at 20 mg kg^-1 (control), or lysozyme at 50 (L50) or 100 mg kg^-1 (L100) diet for 30 days. The results showed that pigs fed with L100 or control had greater average daily gain and gain-to-feed ratio than pigs in the L50 group. Pigs fed with L100 or colistin had greater villus height to crypt depth ratio in jejunum compared with pigs in the L50 group. Pigs fed with L100 had greater serum immunoglobulin A and jejunal secretory immunoglobulin A than control and L50, but lower serum total protein and globulin than control. No differences were observed in the messenger RNA expression of genes related to mucosal cytokines, antioxidant capacity, enzyme activity, and barrier functions among three treatments. The caecal microflora evenness was lower in the L100 group than in the control or L50 group by 16S ribosomal DNA sequencing. Phylogenetic investigation of communities by reconstruction of unobserved states analysis predicted that lysozyme may modify nutrient metabolism by changing intestinal microbial function of pigs.

CONCLUSIONS

Pigs supplemented with 100 mg kg^-1 lysozyme had similar growth performance and intestinal morphology as pigs fed with colistin. This was likely due to the improved systemic and gut immune responses and the reduced microbiota diversity by feeding 100 mg kg^-1 lysozyme. © 2018 Society of Chemical Industry.

Life cycle assessment of alternative swine management practices

Life cycle assessment of various alternative management strategies in the swine industry was performed to evaluate their impact on greenhouse gas (GHG) emissions, cumulative energy use, and cumulative water use. The management strategies included the use of immunocastration (IC), production without ractopamine (NoRAC), production without antimicrobials used for either growth promotion (NoAGP) or disease prevention (NoPREV), production of entire males (boars) (EM), and use of gestation pens (PENS). A common baseline scenario representing standard management practices in the swine industry was created against which all alternative management practices were compared pairwise. The study scope was from cradle-to-farm gate with a functional unit of 1 kg live weight at the farm gate. The baseline and each alternative management scenario was simulated in Pig Production Environmental Footprint Calculator (PPEC) model by varying key variables to populate life cycle inventory inputs for SimaPro V7.3 (Pre' Consultant, the Netherlands), a life cycle assessment modeling program. Increase in GHG emissions, energy use, and water use were observed for NoAGP (1.56, 1.75, and 1.03%, respectively), NoPREV (17.32, 18.40, and 15.58%, respectively), and NoRAC (6.52, 4.87, and 7.52%, respectively) scenarios. For EM scenario, GHG emissions and energy use increased by 2.09 and 3.75%, respectively but water use decreased by 2.29%. Lower GHG emissions, energy use, and water use were observed for PENS (0.97, 1.50, and 0.97%, respectively) and IC (2.39, 2.57, and 2.96%, respectively) scenarios. These changes in the impact categories were statistically significant (P < 0.05) for all scenarios except for changes to GHG emissions for EM and changes to water consumption for PENS and NoAGP. However, the uncertainty analysis showed that the tails of distribution for baseline and alternative management scenario pair overlapped. The impact of management practices on sustainability metrics resulted from differences in pig performance parameters, manure production, feed consumption, etc. between various management practices and the baseline scenario. Due to uncertainties in input parameters, the results should be interpreted as general trends which specifically highlight trade-offs that may result from shifts in production practices. The study identified some of the hot spots in pig production and can be useful in determining best management practices to make swine production more environmentally sustainable.

Dietary Factors in Prevention of Pediatric Escherichia coli Infection: A Model Using Domestic Piglets

Enterotoxigenic Escherichia coli (ETEC) is the major etiological agent causing acute watery diarrhea that is most frequently seen in young children in lower-income countries. The duration of diarrheal symptom may be shortened by antibiotic treatment, but ETEC is relative refractory to common antibiotics. Burgeoning evidence suggests bioactive components that naturally occur in human milk (e.g., lysozyme and oligosaccharides) and plants (e.g., nondigestible carbohydrates and phytochemicals) contain antimicrobial functions are promising preventive measures to control ETEC infection. Although the exact protective mechanisms may vary for each compound and are still not completely understood, they generally act to (1) competitively inhibit the binding of pathogenic bacteria and toxins to gut epithelium; (2) directly kill pathogens; and (3) stimulate and/or enhance host mucosal and systemic immune defense against pathogenic microorganisms. An appropriate ETEC-challenge animal model is critical to evaluate the effect and unveil the mechanism of bioactive compounds in prevention of enteric infection. Despite wide application in biomedical research, rodents do not usually manifest typical clinical signs of enteric infections. The remarkable differences in digestive physiology, immune response, and gut microbiota between rodents and human beings necessitate the use of alternative animal models. Pigs are closely related to humans in terms of genomes, physiology, anatomy of gastrointestinal tracts, digestive enzymes, components of immune system, and gut microbiota. Like human infants and young children, nursing and nursery piglets are more susceptible to ETEC infection and reproduce the clinical signs as observed in humans. Hence, the ETEC-challenge piglet represents a valuable translational model to study pathogenesis and evaluate dietary factors (e.g., milk bioactive compounds, nondigestible carbohydrates, and phytochemicals) as preventive measures for ETEC infection in pediatrics.

Effects of Saccharomyces Cerevisiae Fermentation Products on the Microbial Community throughout the Gastrointestinal Tract of Calves

Simple Summary

Saccharomyces cerevisiae fermentation products (SCFP) are widely used for dairy cows and have been suggested to improve calf performance and health. However, the changes in microbial community along the gut in calves supplemented with SCFP have not been investigated extensively. This manuscript exhibited that calves supplemented with Saccharomyces cerevisiae fermentation products changed the microbial community of GIT and stimulated fibrolytic bacteria (Lachnospiraceae and Ruminococcaceae) colonization in early rumen and large intestine, respectively. Those alternations of microbiota in GIT might explain how SCFP works in calves.

Abstract

The effect of Saccharomyces cerevisiae fermentation products (SCFP) on improving growth and health of calves could be attributed to the ability of SCFP to modulate the microbiota in the gastrointestinal tract (GIT). However, the changes in microbial community along the gut in calves supplemented with SCFP have not been investigated extensively. The aims of this study were to investigate the effect of SCFP on microbial communities in each sites of GIT using high-throughput sequencing technique. Fifteen Holstein male calves were used and randomly assigned to 1 of the 3 treatments including a calf starter containing 0 (Control, CON), 0.5 (SCFP1) or 1% SCFP (SCFP2, Original XPC, Diamond V, Cedar Rapids, IA, USA) of dry matter from day 4 to 56. The supplemented calves were fed with an additional 1 g/d SCFP (SmartCare, Diamond V, Cedar Rapids, IA, USA) in milk from day 2 to 30. Rumen fluid was sampled at day 28 of age via esophageal tube. All calves were slaughtered and gastrointestinal samples collected on day 56. Inclusion of SCFP increased the microbial species richness in the large intestine. The SCFP also affected the bacterial community at an early age in the rumen and later in rectum microbiota. Supplementation of SCFP stimulated colonization by fibrolytic bacteria (Lachnospiraceae and Ruminococcaceae) in rumen and large intestine, respectively. No differences were found between SCFP1 and SCFP2. This is the first study to analyze the effect of SCFP on bacterial community of the GIT microbiota in calves. The results provide the basic bacterial community information, which helps us understand the mechanism of action of SCFP for improving the health and performance of pre-weaning calf.

Comparative efficacy of antibiotic growth promoter and benzoic acid on growth performance, nutrient utilization, and indices of gut health in nursery pigs fed corn–soybean meal diet

Benzoic acid (BA) supplement was evaluated as an alternative to antimicrobial growth promoter (AGP). Ninety-six piglets (21-d-old at weaning) were placed in pens (four piglets pen−1) based on body weight (BW) and allocated (n = 8) to either control corn–soybean meal diet or control + in-feed antibiotic (AGP, 220 mg chlortetracycline hydrochloride and 31.2 mg tiamulin kg−1) or control + 0.5% BA. Feed intake and BW were measured weekly. Fecal scores for incidence of diarrhea and fecal samples for apparent total tract digestibility (ATTD) of components were taken in week 2. One pig per pen was euthanized on day 14 for jejunal histomorphology and digesta for pH and short-chain fatty acids concentration. In weeks 1–6, pigs fed AGP and BA had better (P < 0.01) gain to feed ratio compared with control fed pigs. On day 12, pigs fed AGP and BA showed lower (P = 0.01) fecal score than control fed pigs. Pigs fed BA had (P < 0.05) higher ATTD of crude protein and taller villi compared with the control or AGP fed pigs. Pigs fed AGP showed higher (P = 0.05) lactic acid concentrations than pigs fed BA, however, none differed (P > 0.05) with control pigs. In conclusion, BA supported piglet growth performance to the same extent as AGP.

Non-antibiotic feed additives in diets for pigs: A review

A number of feed additives are marketed to assist in boosting the pigs' immune system, regulate gut microbiota, and reduce negative impacts of weaning and other environmental challenges. The most commonly used feed additives include acidifiers, zinc and copper, prebiotics, direct-fed microbials, yeast products, nucleotides, and plant extracts. Inclusion of pharmacological levels of zinc and copper, certain acidifiers, and several plant extracts have been reported to result in improved pig performance or improved immune function of pigs. It is also possible that use of prebiotics, direct-fed microbials, yeast, and nucleotides may have positive impacts on pig performance, but results have been less consistent and there is a need for more research in this area.

Effect of chicken egg anti-F4 antibodies on performance and diarrhea incidences in enterotoxigenic Escherichia coli K88+-challenged piglets

The aim was to evaluate the effects of dietary supplementation of spay-dried whole egg containing anti-F4 antibodies (SDWE) against recombinantly produced F4 antigens in enterotoxigenic Escherichia coli K88⁺ (ETEC)-challenged piglets. Twenty-seven 21-d-old and individually housed piglets were randomly allotted to 3 treatments consisting of a wheat-soybean meal basal diet containing either 0 (control egg powder; CEP), 0.1% (SDWE1) or 0.4% (SDWE2) SDWE. After a 7-d adaptation period, blood samples were collected from all pigs, and pigs were weighed and orally challenged with an ETEC inoculum. Blood was sampled at 24 and 48 h post-challenge, and diarrhea incidences and scores were recorded. On d 14, all pigs were weighed and then euthanized to obtain intestinal tissue samples for histomorphology measurement. During the pre-challenge period, pigs fed the SDWE showed a linear improvement (P < 0.05) in average daily gain (ADG) and gain to feed ratio (G:F), but there were no differences among treatments in growth performance during the post-challenge period. Diarrhea incidences and scores, fecal shedding of ETEC, plasma urea nitrogen content and intestinal histomorphology were similar among treatments. The results show that 0.4% SDWE supported greater piglet performance before challenge although such benefits were not evident during the post-challenge period at either 0.1% or 0.4% supplementation.

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.

Effects of supplementing sow diets with fermented corn and soybean meal mixed feed during lactation on the performance of sows and progeny

In the present study, two experiments were performed to study the effects of feeding fermented corn and soybean meal mixed feed (FMF) with Bacillus subtilis and Enterococcus faecium to lactating sows on the performance of the sows and their progeny. In experiment 1, 60 sows were allocated to the following three dietary treatments: 1) sows fed a corn and soybean meal basal diet (control) from day 3 before parturition to weaning, 2) sows fed a diet with 7.5% FMF, and 3) sows fed a diet with 15% FMF. Results indicated that feeding 15% FMF significantly improved (P < 0.05) the sows' ADFI, the individual piglet weaning weights, and piglet weight gain and reduced (P < 0.05) the backfat loss of sows compared with the control group. However, the 7.5% FMF treatment did not alter the performance of the sows or their progeny. Therefore, we considered the level of 15% FMF to be more efficient than 7.5% FMF. To verify the results of experiment 1, we performed experiment 2, in which 60 sows at 111 d of gestation were allocated into the following two dietary treatments: 1) sows fed a basal lactation diet (control) from d 111 of gestation to weaning and 2) sows fed a basal diet with 15% FMF. Compared with the control group, 15% FMF inclusion significantly increased (P < 0.05) the sows' ADFI, litter weight gain, and individual piglet weight gain during lactation and markedly decreased the backfat loss of sows (P < 0.05) and piglet diarrhea incidence (P < 0.05). Additionally, the milk yield and IgA contents of the milk in sows fed 15% FMF were greater (P < 0.05) than those of the control group. Furthermore, the apparent total tract digestibility of GE, DM, and total P of sows was increased (P < 0.05) with 15% FMF supplementation. Therefore, the present study indicates that supplementing sow diets with 15% FMF from parturition to weaning has the potential to 1) increase sow ADFI, milk production, milk IgA content, and nutrient digestibility and promote sow reproductive performance by shortening the weaning-to-estrous interval and 2) promote the growth performance of their progeny and decrease diarrhea incidence.

Dietary grape seed proanthocyanidins (GSPs) improve weaned intestinal microbiota and mucosal barrier using a piglet model

Proanthocyanidins have been suggested as an effective antibiotic alternative, however their mechanisms are still unknown. The present study investigated the effects of grape seed proanthocyanidins on gut microbiota and mucosal barrier using a weaned piglet model in comparison with colistin. Piglets weaned at 28 day were randomly assigned to four groups treated with a control ration, or supplemented with 250 mg/kg proanthocyanidins, kitasamycin/colistin, or 250 mg/kg proanthocyanidins and half-dose antibiotics, respectively. On day 28, the gut chyme and tissue samples were collected to test intestinal microbiota and barrier function, respectively. Proanthocyanidins treated piglets had better growth performance and reduced diarrhea incidence (P < 0.05), accompanied with decreased intestinal permeability and improved mucosal morphology. Gene sequencing analysis of 16S rRNA revealed that dietary proanthocyanidins improved the microbial diversity in ileal and colonic digesta, and the most abundant OTUs belong to Firmicutes and Bacteroidetes spp.. Proanthocyanidins treatment decreased the abundance of Lactobacillaceae, and increased the abundance of Clostridiaceae in both ileal and colonic lumen, which suggests that proanthocyanidins treatment changed the bacterial composition and distribution. Administration of proanthocyanidins increased the concentration of propionic acid and butyric acid in the ileum and colon, which may activate the expression of GPR41. In addition, dietary proanthocyanidins improved the antioxidant indices in serum and intestinal mucosa, accompanied with increasing expression of barrier occludin. Our findings indicated that proanthocyanidins with half-dose colistin was equivalent to the antibiotic treatment and assisted weaned animals in resisting intestinal oxidative stress by increasing diversity and improving balance of gut microbes.

Combined effects of chitosan and microencapsulated Enterococcus faecalis CG1.0007 probiotic supplementation on performance and diarrhea incidences in enterotoxigenic Escherichia coli K88+ challenged piglets

The aim of this study was to investigate the combined effects of chitosan oligosaccharide (COS) and a microencapsulated Enterococcus faecalis CG1.0007 probiotic (PRO) on growth performance and diarrhea incidences in enterotoxigenic Escherichia coli (ETEC) K88⁺ challenged piglets in a 14-d study. Thirty piglets, 7.19 ± 0.52 kg initial BW weaned at 21 ± 1 d, were allotted to 5 treatment groups (n = 6) consisting of a corn-soybean meal diet with no additive (negative control, NC), NC + 0.25% chlortetracycline (positive control, PC), NC + 400 mg/kg COS (COS), NC + 100 mg/kg PRO (PRO) and NC + a combination of COS and PRO (CPRO). Pigs were individually housed in cages, acclimated to treatments for a 7-d period and had ad libitum access to feed and water throughout the study. On d 8, pigs were weighed, blood samples were collected, and then orally challenged with 6 mL (1 × 10¹¹ cfu/mL) of freshly grown ETEC inoculum. During post-challenge period, blood was sampled at 24 and 48 h to determine plasma urea nitrogen (PUN), and diarrhea incidences and fecal consistency scores were recorded from d 9 to 12. On d 14, all pigs were weighed and then euthanized to obtain intestinal tissue samples for histomorphometric measurements. Growth performance responses were similar among treatments during the pre- and post-challenge periods. There were no significant differences in PUN content, incidences of diarrhea, and fecal consistency scores among treatments. The intestinal histomorphology results did not differ significantly among treatments except for PC with increased (P = 0.0001) villus:crypt ratio compared with the NC. Under the conditions of the present study, it can be concluded that supplementation of piglet diets with 400 mg/kg COS, 100 mg/kg microencapsulated PRO or their combination did not significantly improve piglet growth performance both during the pre- and post-ETEC K88⁺ oral inoculation. Also, there were no significant reduction of incidences and severity of diarrhea after challenge compared with the control group.

Effects of live yeast dietary supplementation on nutrient digestibility and fecal microflora in beagle dogs

The effects of live yeast (strain CNCM I-4407; Actisaf Sc 47; Phileo Lesaffre Animal Care, Marcq-en-Baroeul, France) administration on nutrient digestibility and fecal microflora in dogs were investigated. The study included 24 young beagle dogs. They were allocated in control and live yeast (LY) groups (6 males and 6 females in each). During the Adaptation (d 1 to 28) and Trial (d 29 to 70) periods, the dogs received a standard dry pelleted diet. In the Trial period, the LY dogs were given capsuled Actisaf Sc 47 at 1 g/kg live weight with at 2.9 × 10 cfu/g. The control dogs received empty capsules. Live weight and feed consumption were recorded. Blood samples for complete blood count (CBC) and serum biochemistry (urea, creatinine, alkaline phosphatase, and alanine aminotransferase) and fecal samples for pH, microbiology, DM, lactic acid, and ammonia and digestibility evaluation were collected during the Trial period from each dog. The LY dogs had a higher ( < 0.05) weight gain during the Trial period than the control ones. Feed consumption was not adversely affected by LY. The CBC values and urea, creatinine, alkaline phosphatase, and alanine aminotransferase were not adversely affected by LY. Live yeast did not significantly influence pH of fresh feces. Fecal lactic acid and ammonia concentrations were not affected. The LY dogs showed lower ( < 0.05) Escherichia coli and fecal enterococci counts in feces than the control ones. Lactic acid bacteria, Clostridium perfringens, and total coliforms did not show any significant differences between the treatments. The LY dogs showed a higher ( < 0.05) apparent digestibility of NDF. Digestibilities of DM, ash, crude fiber, CP, and fat were not influenced.

Review: Utilization of yeast of Saccharomyces cerevisiae origin in artificially raised calves

Yeast of Saccharomyces cerevisiae (SCY) origin has over long time been incorporated into domestic animal diets. In calves, several products have offered improved performance and health. Although several types of research have been completed, the mode of action of SCY is not clear in calves. Under this review, we have highlighted the works available in the literature on the use of SCY in calves performance, health, immunity, and the gut environment. Both active live yeast and yeast culture have positive effects on growth, rumen, small intestines, immunity and general health of the calf. Specifically, SCY can improve DMI, growth, feed efficiency and reduce diarrhea in calves. Furthermore, subtle improvements are seen in rumen fermentation (increased butyrate production) and rumen papillae growth. These positive results are, however, more pronounced in calves that are under stress or exposed to significant levels of disease-causing agents. There is a need for further research in areas such as gut morphology, gut microbiology and immunity using latest molecular methods to fully understand how SCY helps the growth and development of calves.

Effects of Ex Vivo Infection with ETEC on Jejunal Barrier Properties and Cytokine Expression in Probiotic-Supplemented Pigs

BACKGROUND AND AIM

Enterotoxigenic Escherichia coli (ETEC) strains are involved in piglet post-weaning diarrhea. Prophylactic measures including probiotics have been examined in infection experiments with live piglets. In the present study, we have tested whether the early effects of ETEC infection can also be evoked and studied in a model in which ETEC is added to whole mucosal tissues ex vivo, and whether this response can be modulated by prior supplementation of the piglets with probiotics.

METHODS

Jejunal barrier and transport properties of Enterococcus faecium-supplemented or control piglets were assessed in Ussing chambers. Part of the epithelia was challenged with an ETEC strain at the mucosal side. Fluxes of fluorescein as a marker of paracellular permeability, and the expression of selected tight junction (TJ) proteins and of proinflammatory cytokines were measured.

RESULTS

The addition of ETEC ex vivo induced an increase in transepithelial resistance peaking in the first 2 h with a concomitant reduction in fluorescein fluxes, indicating tightening effects on barrier function. The response of short-circuit current after stimulation with PGE₂ or glucose was reduced in epithelia treated with ETEC. ETEC induced a decrease in the TJ protein claudin-4 in the control diet group after 280 min and an increase in the mRNA expression of the proinflammatory cytokines interleukin-8 and TNF-α in both groups after 180 min.

CONCLUSIONS

The addition of ETEC ex vivo affected barrier function and transport properties of the jejunal tissues and enhanced cytokine expression. The differences in claudin-4 expression in the jejunum might indicate a beneficial effect of E. faecium prefeeding.

Effects of dietary supplementation of Saccharomyces cerevisiae fermentation product to sows and their offspring on growth and meat quality

This study evaluated the effects of long term dietary supplementation of Saccharomyces cerevisiae fermentation product (SCFP) in the diets for sows and offspring on growth performance, intestinal morphology, volatile fatty acid production, and carcass characteristics of offspring. Newly weaned pigs (n = 256) were allotted to 4 treatments based on a 2 × 2 factorial arrangement. Each treatment had 8 pens with 8 pigs per pen. First factor was maternal dietary effects (no SCFP, or SCFP at 12.0 and 15.0 g/d through gestation and lactation, respectively) and the second factor was dietary supplementation of SCFP to offspring (no SCFP, or SCFP at 0.2 and 0.1% for nursery and finisher, respectively). Pigs were on a 6-phase feeding program with assigned diets from nursery to slaughter. Body weights (BW) and feeder weights were measured at the end of each phase. On d 5 after weaning, 1 pig per pen was euthanized to evaluate intestinal morphology and volatile fatty acid production. At 115 kg of BW, 1 pig from each pen was slaughtered to measure carcass characteristics. Feeding diets with SCFP to sows or to their offspring had no effect on BW, overall average daily gain (ADG), average daily feed intake (ADFI), and gain-to-feed (G:F) ratio during the nursery or finisher period. Feeding SCFP to sows tended to increase (P = 0.098) cecal butyric acid production in their offspring. Pigs with SCFP tended to have a greater (P = 0.084) concentration of acetic acid but a reduced (P = 0.054) propionic acid in colon digesta than pigs without SCFP regardless of maternal feeding regimen. Loin marbling scores were greater (P = 0.043) in pigs with SCFP than those without SCFP regardless of maternal feeding regimen. Overall, supplementation of SCFP in sow diets did not affect growth performance or intestinal morphology of their offspring. Supplementation of SCFP in diets of offspring from nursery to slaughter had little effect on growth performance. However, inclusion of SCFP from nursery to slaughter improved marbling score possibly by increased acetic acid and butyric acid production in the large intestine.

Growth performance, gastrointestinal microbial activity, and immunological response of piglets receiving microencapsulatedEnterococcus faecalisCG1.0007 and enzyme complex after an oral challenge withEscherichia coli(K88)

The aim of this study was to determine effects of dietary microencapsulated Enterococcus faecalis CG1.0007 probiotic and multienzyme complex (MC) in Enterotoxigenic Escherichia coli K88 (ETEC) challenged piglets. Thirty-six, 21-d-old weanling pigs were randomly allotted to four dietary treatments: a wheat–barley based negative control (NC), NC + MC, NC + probiotic, and NC + MC + probiotic. After 7-d acclimatization to treatments, pigs were weighed, blood was sampled, and then the pigs were orally challenged with an ETEC inoculum. After the challenge, blood was sampled at different time points; performance measures and fecal consistency scores were recorded; and on day 14, all pigs were killed to obtain intestinal tissue samples. During prechallenge, pigs receiving enzyme, probiotic, and a combination of both showed a significant improvement in daily gain (P = 0.03) and feed efficiency (P = 0.04) compared with control. During the postchallenge period, a greater (P = 0.05) ileal villus height was observed for diets supplemented with probiotic alone. Overall, pigs fed diets with probiotic alone also showed less incidence of diarrhea (P = 0.04) compared with control. In summary, the results indicate that dietary supplementation with microencapsulated Enterococcus faecalis CG1.0007 in weaned piglets challenged with ETEC was effective in controlling diarrhea.