Gastrointestinal health and function in weaned pigs: a review of feeding strategies to control post-weaning diarrhoea without using in-feed antimicrobial compounds

Impact of particle size of cereals and soyabean meal on the intestinal development of weanling pigs and growth performance after an enteric challenge with F4-positive enterotoxigenic E. coli

The objectives were to determine the interactive effect of particle size of soyabean meal (SBM) and whole wheat, barley and wheat bran (CER) on growth performance of weanling pigs after an enterotoxigenic Escherichia coli F4 challenge (Experiment 1) and on gastrointestinal (GIT) development immediately after weaning (Experiment 2). Experiment 1 consisted of 192 pigs (24 ± 3 days of age; 7.4 ± 1.1 kg weaning bodyweight [BW]) selected for Escherichia coli (E. coli) F4 susceptibility. Pigs were given an oral E. coli inoculum at postweaning day 7, to induce an enteric health challenge. Experiment 2 consisted of 40 pigs (24 ± 3 days of age; 7.2 ± 1.0 kg weaning BW) that were killed on postweaning day 8 or 9, to determine the effects of particle size on GIT development and functionality. Four experimental diets were used in a 2 × 2 factorial design: (1) coarse CER and coarse SBM, (2) coarse CER and fine SBM (CERcSBMf), (3) fine CER and coarse SBM, or (4) fine CER and fine SBM (CERfSBMf). Results showed no interaction between SBM and CER coarseness on growth performance, GIT development and functionality. Diarrhoea incidence was higher (p < 0.05) for CERfSBMf during the 2 weeks following the E. coli challenge compared to the other diets. Daily gain and feed intake during this period were higher (p < 0.05) for pigs fed CERc compared to CERf. Empty stomach weight tended to be greater by 8% (p = 0.09) for CERc compared to CERf. Gastric protein (p = 0.05) and starch (p = 0.04) disappearances were greater for SBMf compared to SBMc. Thus, CERcSBMf resulted in the best growth performance and lowest diarrhoea incidence during the 2 weeks following the E. coli challenge, which may be explained by changes in stomach functionality but not by changes in other parts of the GIT.

Adaptation of an in-vitro digestion model with different zinc-supplementation strategies on nutrient degradation of piglets

In-vitro studies are widely used in nutrition research. Two major challenges using in-vitro models in animal nutrition research are the individual adaptation of in-vitro digestion models to varying physiological conditions and small digesta output limiting sample material for further analysis. Since several years, the use of zinc in animal production has been legally reduced to control zinc emissions. Earlier, zinc doses around 3000 mg/kg diet were used to prevent post-weaning diarrhea and promote growth in weaning piglets. The first aim of this study was to adapt an in-vitro digestion system for piglets with increased sample output. The second aim was to study the effect of a titanium-bound zinc source at legal dietary inclusion levels on nutrient degradation in an in-vitro digestion model. The experiment was conducted in a 2x2 factorial design incubating 2 different feeds (1. control feed: a commercial piglet diet containing 75 mg zinc per kg diet and 2. treatment feed: control feed with 50 mg of a titanium-bound zinc oxide) in in-situ digestion bags in the Ankom Daisy® incubator with or without digestive enzymes (pepsin, pancreatic enzymes and bile salts). Residuals of incubated feed were analyzed for crude ash, crude protein and starch. The addition of pepsin, pancreatic enzymes and bile salts significantly increased organic matter, crude protein and starch degradation from the digested feed, therefore making the distinction of nutrient disappearance due to enzyme activity versus due to dissolution possible. In conclusion we established an in-vitro digestion model to evaluate the effect of addition of a new zinc source on the enzymatic digestion in piglets. However, addition of the new zinc source did not significantly improve nutrient degradation in the in-vitro digestion model.

Interplay of poultry-microbiome interactions - influencing factors and microbes in poultry infections and metabolic disorders

1. The poultry microbiome and its stability at every point in time, either free range or reared under different farming systems, is affected by several environmental and innate factors. The interaction of the poultry birds with their microbiome, as well as several inherent and extraneous factors contribute to the microbiome dynamics. A poor understanding of this could worsen poultry heath and result in disease/metabolic disorders.2. Many diseased states associated with poultry have been linked to dysbiosis state, where the microbiome experiences some perturbation. Dysbiosis itself is too often downplayed; however, it is considered a disease which could lead to more serious conditions in poultry. The management of interconnected factors by conventional and emerging technologies (sequencing, nanotechnology, robotics, 3D mini-guts) could prove to be indispensable in ensuring poultry health and welfare.3. Findings showed that high-throughput technological advancements enhanced scientific insights into emerging trends surrounding the poultry gut microbiome and ecosystem, the dysbiotic condition, and the dynamic roles of intrinsic and exogenous factors in determining poultry health. Yet, a combination of conventional, -omics based and other techniques further enhance characterisation of key poultry microbiome actors, their mechanisms of action, and roles in maintaining gut homoeostasis and health, in a bid to avert metabolic disorders and infections.4. In conclusion, there is an important interplay of innate, environmental, abiotic and biotic factors impacting on poultry gut microbiome homoeostasis, dysbiosis, and overall health. Associated infections and metabolic disorders can result from the interconnected nature of these factors. Emerging concepts (interkingdom or network signalling and neurotransmitter), and future technologies (mini-gut models, cobots) need to include these interactions to ensure accurate control and outcomes.

Piglets performance, nutrient digestibility and gut health in response to feeding Ulva lactuca seaweed supplemented with a recombinant ulvan lyase or a commercial carbohydrase mixture

Ulva lactuca, a green seaweed, may be an alternative source of nutrients and bioactive compounds for weaned piglets. However, it has a recalcitrant cell wall rich in a sulphated polysaccharide - ulvan - that is indigestible to monogastrics. The objective of this study was to evaluate the effect of dietary incorporation of 7% U. lactuca, combined with carbohydrases supplementation (commercial carbohydrase mixture or recombinant ulvan lyase), on growth performance, nutrient digestibility and gut health parameters (morphology and microbiota) of weaned piglets. The experiment was conducted over 14 days using 40 weaned piglets randomly allocated to one of four experimental diets: a control diet based on wheat-maize-soybean meal, a diet with 7% U. lactuca replacing the control diet (UL), a diet with UL supplemented with 0.005% Rovabio® Excel AP, and a diet with UL supplemented with 0.01% of a recombinant ulvan lyase. The dietary treatments had no major effects on growth performance, nitrogen balance and gut content variables, as well as histological measurements. Contrarily, dry matter and organic matter digestibility decreased with dietary seaweed inclusion, while hemicellulose digestibility increased, suggesting a high fermentability of this cell wall fraction independently of carbohydrases supplementation. Some beneficial microbial populations increased as a consequence of enzymatic supplementation (e.g., Prevotella), while seaweed diets as a whole led to an increased abundance of Shuttleworthia, Anaeroplasma and Lachnospiraceae_NK3A20_group, all related with a healthier gut. It also decreased Lactobacillus when compared to controls, which is possibly related to increased bioavailability of seaweed zinc. This study indicates that, under these experimental conditions, up to 7% dietary U. lactuca has no detrimental effect on piglet growth, despite decreasing acid detergent fibre digestibility. Carbohydrases supplementation of Ulva diets is not required at this incorporation level.

Impact of Nutritional Strategies to Prevent Post-Weaning Diarrhoea on Performance, Behaviour, and Microbiota in Piglets from Organic Farming

Organic livestock farming is committed to high environmental and animal welfare standards, although pathologies such as post-weaning diarrhoea (PWD) may appear. The main objective of this study was to assess nutritional strategies to prevent PWD in organic piglets. A total of 134 weaned piglets were fed one of three diets: high crude protein (17.8%, HCP), low crude protein (16.8%, LCP), and low crude protein supplemented with liquid whey (LCP+W). Piglets were assessed weekly for four weeks on the following parameters: diarrhoea incidence, additional health parameters, average daily gain, and behaviour. Faecal samples were taken to analyse the intestinal microbiota composition. Data were analysed using LMM and GLMM models and Shannon and Whittaker indexes. No significant effect of diet on diarrhoea incidence was found, but the LCP+W diet increased average daily gain. Pigs fed the LCP+W diet presented a lower percentage of drinking and negative social behaviour compared with the HCP diet, and LCP pigs presented higher exploration compared with HCP. In addition, LCP+W piglets showed a higher abundance of the beneficial genus Frisingicoccus. Although liquid whey did not reduce diarrhoea incidence, the benefits found in growth, microbiota composition, and reduced negative social behaviour indicate that it could be an optimal supplement to organic diets.

Nutrition strategies to control post-weaning diarrhea of piglets: From the perspective of feeds

Post-weaning diarrhea (PWD) is a globally significant threat to the swine industry. Historically, antibiotics as well as high doses of zinc oxide and copper sulfate have been commonly used to control PWD. However, the development of bacterial resistance and environmental pollution have created an interest in alternative strategies. In recent years, the research surrounding these alternative strategies and the mechanisms of piglet diarrhea has been continually updated. Mechanically, diarrhea in piglets is a result of an imbalance in intestinal fluid and electrolyte absorption and secretion. In general, enterotoxigenic Escherichia coli (ETEC) and diarrheal viruses are known to cause an imbalance in the absorption and secretion of intestinal fluids and electrolytes in piglets, resulting in diarrhea when Cl- secretion-driven fluid secretion surpasses absorptive capacity. From a perspective of feedstuffs, factors that contribute to imbalances in fluid absorption and secretion in the intestines of weaned piglets include high levels of crude protein (CP), stimulation by certain antigenic proteins, high acid-binding capacity (ABC), and contamination with deoxynivalenol (DON) in the diet. In response, efforts to reduce CP levels in diets, select feedstuffs with lower ABC values, and process feedstuffs using physical, chemical, and biological approaches are important strategies for alleviating PWD in piglets. Additionally, the diet supplementation with additives such as vitamins and natural products can also play a role in reducing the diarrhea incidence in weaned piglets. Here, we examine the mechanisms of absorption and secretion of intestinal fluids and electrolytes in piglets, summarize nutritional strategies to control PWD in piglets from the perspective of feeds, and provide new insights towards future research directions.

Dietary nutrition, intestinal microbiota dysbiosis and post-weaning diarrhea in piglets

Weaning is a critical transitional point in the life cycle of piglets. Early weaning can lead to post-weaning syndrome, destroy the intestinal barrier function and microbiota homeostasis, cause diarrhea and threaten the health of piglets. The nutritional components of milk and solid foods consumed by newborn animals can affect the diversity and structure of their intestinal microbiota, and regulate post-weaning diarrhea in piglets. Therefore, this paper reviews the effects and mechanisms of different nutrients, including protein, dietary fiber, dietary fatty acids and dietary electrolyte balance, on diarrhea and health of piglets by regulating intestinal function. Protein is an essential nutrient for the growth of piglets; however, excessive intake will cause many harmful effects, such as allergic reactions, intestinal barrier dysfunction and pathogenic growth, eventually aggravating piglet diarrhea. Dietary fiber is a nutrient that alleviates post-weaning diarrhea in piglets, which is related to its promotion of intestinal epithelial integrity, microbial homeostasis and the production of short-chain fatty acids. In addition, dietary fatty acids and dietary electrolyte balance can also facilitate the growth, function and health of piglets by regulating intestinal epithelial function, immune system and microbiota. Thus, a targeted control of dietary components to promote the establishment of a healthy bacterial community is a significant method for preventing nutritional diarrhea in weaned piglets.

Impact of dietary Laminaria digitata with alginate lyase or carbohydrase mixture on nutrient digestibility and gut health of weaned piglets

Laminaria digitata is a brown seaweed rich in prebiotic polysaccharides, mainly laminarin, but its alginate-rich cell wall could compromise nutrient access. Carbohydrase supplementation, such as individual alginate lyase and carbohydrases mixture (Rovabio® Excel AP), could enhance nutrient digestibility and prebiotic potential. This study aimed to evaluate the effect of these enzymes on nutrient digestibility and gut health of weaned piglets fed with 10% L. digitata. Diets did not affect growth performance (P > 0.05). The majority of the feed fractions had similar digestibility across all diets, but the supplementation of alginate lyase increased hemicellulose digestibility by 3.3% compared to the control group (P = 0.047). Additionally, we observed that algal zinc was more readily available compared to the control group, even without enzymatic supplementation (P < 0.001). However, the increased digestibility of some minerals, such as potassium, raises concerns about potential mineral imbalance. Seaweed groups had a higher abundance of beneficial bacteria in colon contents, such as Prevotella, Oscillospira and Catenisphaera. Furthermore, the addition of alginate lyase led to a lower pH in the colon (P < 0.001) and caecum (P < 0.001) of piglets, which is possibly a result of released fermentable laminarin, and is consistent with the higher proportion of butyric acid found in these intestinal compartments. L. digitata is a putative supplement to enhance piglet gut health due to its prebiotic polysaccharides. Alginate lyase supplementation further improves nutrient digestibility and prebiotic potential. These results suggest the potential use of L. digitata and these enzymatic supplements in commercial piglet-feeding practices.

Next-generation probiotic candidates targeting intestinal health in weaned piglets: Both live and heat-killed Akkermansia muciniphila prevent pathological changes induced by enterotoxigenic Escherichia coli in the gut

The use of next-generation probiotics (NGP) in pigs for combating diseases has been subject to limited research. Here we explored the potential of a well-known NGP candidate Akkermansia muciniphila targeting pig gut health. In the first screening experiment, we found that the abundance of A. muciniphila peaked at 14 d old but decreased at weaning (21 d old; P < 0.05), suggesting the weaning period may be an effective window for A. muciniphila intervention. Following that, 48 crossbred weaned pigs at 28 d old were randomly assigned to five groups: control (CON), high/low live A. muciniphila (HA/LA), and high/low heat-killed A. muciniphila (HIA/LIA). From 1 to 28 d old, the CON group received gastric infusion of anaerobic sterile saline every other day; the HA and LA groups were gavaged every other day with 1 × 1010 CFU/5 mL and 5 × 108 CFU/5 mL live A. muciniphila, respectively; and the HIA and LIA groups were gavaged every other day with 1 × 1010 CFU/5 mL and 5 × 108 CFU/5 mL heat-killed A. muciniphila, respectively. At d 29, pigs in the CON group were randomly and equally divided into two groups, one of which was named the enterotoxigenic Escherichia coli (ETEC) group, and all groups except CON received a 5-d ETEC challenge. The supplementation of A. muciniphila numerically reduced the diarrhea rate of weaned pigs compared to the pigs that only received the ETEC challenge (P = 0.57), but the LIA group had a higher diarrhea rate than the CON group (P < 0.05). Consistent with this, the supplementation of A. muciniphila improved the small intestinal morphology and structure, proportion of CD4+ T lymphocytes in the blood, as well as the expression of genes related to intestinal barrier and antioxidant indices of pigs with ETEC challenge, especially for the LA group (P < 0.05). Meanwhile, A. muciniphila supplementation reduced the expression of ETEC virulence factor genes in the ileum and colon of pigs challenged by ETEC (P < 0.05). Therefore, A. muciniphila may protect the intestinal health of weaned piglets from damage caused by ETEC infection, but the effect may vary depending on the concentration and activity of A. muciniphila.

The impacts of animal agriculture on One Health-Bacterial zoonosis, antimicrobial resistance, and beyond

The industrialization of animal agriculture has undoubtedly contributed to the improvement of human well-being by increasing the efficiency of food animal production. At the same time, it has also drastically impacted the natural environment and human society. The One Health initiative emphasizes the interdependency of the health of ecosystems, animals, and humans. In this paper, we discuss some of the most profound consequences of animal agriculture practices from a One Health perspective. More specifically, we focus on impacts to host-microbe interactions by elaborating on how modern animal agriculture affects zoonotic infections, specifically those of bacterial origin, and the concomitant emergence of antimicrobial resistance (AMR). A key question underlying these deeply interconnected issues is how to better prevent, monitor, and manage infections in animal agriculture. To address this, we outline approaches to mitigate the impacts of agricultural bacterial zoonoses and AMR, including the development of novel treatments as well as non-drug approaches comprising integrated surveillance programs and policy and education regarding agricultural practices and antimicrobial stewardship. Finally, we touch upon additional major environmental and health factors impacted by animal agriculture within the One Health context, including animal welfare, food security, food safety, and climate change. Charting how these issues are interwoven to comprise the complex web of animal agriculture's broad impacts on One Health will allow for the development of concerted, multidisciplinary interventions which are truly necessary to tackle these issues from a One Health perspective.

Progression of swine fecal microbiota during early stages of life and its association with performance: a longitudinal study

BACKGROUND

It is vital to understand healthy gut microbiota composition throughout early life stages when environments are changing, and immunity is developing. There are limited large-scale longitudinal studies classifying healthy succession of swine microbiota. The objectives of this study were to (a) determine the microbiota composition of fecal samples collected from piglets within a few days after birth until one-week post-weaning, and (b) investigate the associations of early fecal microbiota with pig growth performance in nursery and later growing stages. Fecal samples were collected from nine cohorts of 40 pigs (n = 360) from distinct farrowing sources in Ontario and Quebec, Canada at four timepoints from birth to one-week post-weaning, with pig body weight was recorded at each fecal sampling.

RESULTS

Microbiota was dominated by the phyla Firmicutes, Bacteroides and Proteobacteria. There were notable differences in genera abundance between pigs from different provinces and farming systems. Over the early life stage, the genera Bacteroides, Escherichia/Shigella, and Clostridium cluster XIVa were abundant preweaning, while Prevotella dominated post-weaning. Hierarchical clustering identified three major stages of microbiota development, each associated with distinct composition. Stage one occurs from birth to 7 days, stage two from 7 days after birth until weaning, and stage three from weaning to one-week post-weaning. Three enterotypes were identified in stage two that showed differences in growth before weaning, and in the grower production stage. Piglets with a microbiota enterotype characterized by higher abundance of Prevotella and unclassified Ruminococcaceae had lower growth performance in the pre-weaning stage, and the growing stage.

CONCLUSION

These findings help identify the timing of microbiota shifts across early swine life which may be the optimal time for external intervention to shift the microbiota to a beneficial state. The project findings should help decrease antimicrobial use, increase animal welfare, and have positive economic impacts.

Effects of puerarin as a feed additive on the laying performance, egg quality, endocrine hormones, antioxidant capacity, and intestinal morphology of aged laying hens

The aim of this study was to investigate the effects of puerarin (Pue), a phytoestrogen, on the production performance, egg quality, endocrine hormones, antioxidant capacity, and intestinal morphology in aged laying hens. A total of 180 Hy-Line Brown hens aged 480 d were randomly divided into 4 groups (n = 45 per group) and fed 0, 200, 400, and 800 mg/kg of Pue (Con, L-Pue, M-Pue, and H-Pue, respectively) during a 42-d experiment. Compared with the Con treatment, supplementation with H-Pue improved laying performance and egg quality by significantly increasing egg production, average egg weight, albumen height, yolk weight, and Haugh unit (P < 0.05) while decreasing the feed conversion ratio (P < 0.05). A diet supplemented with H-Pue significantly decreasing serum total triglycerides, total cholesterol, and low-density lipoprotein cholesterol, alanine aminotransferase (P < 0.05), and significantly increasing serum levels of follicle-stimulating hormone, luteinizing hormone and progesterone (P < 0.05). Antioxidant activity was improved by significantly increasing the activity of total antioxidant capacity, glutathione peroxidase and catalase but decreasing malondialdehyde levels in serum, jejunum, and ileum (P < 0.05), and superoxide dismutase activity exhibited a significantly increase in the jejunum and ileum (P < 0.05). Villus height and the ratio of villus height to crypt depth (P < 0.05) were significantly increased in the jejunum and ileum. In the jejunal and ileal mucosa, the three treatment groups increased the mRNA expression levels of Claudin-1 and Claudin-2 compared with Con (P < 0.05), and no significant effect was observed on the expression of Occludin and ZO-1. The results showed that dietary supplementation with Pue could improve the laying performance, egg quality, antioxidant capacity, hormonal profile, and intestinal morphology of aged laying hens.

Effects of increasing dietary arginine supply during the three first weeks after weaning on pig growth performance, plasma amino acid concentrations, and health status

A total of 425 weaned pigs (Exp. 1: 225 pigs [5.8 ± 0.9 kg]; Exp. 2: 200 pigs [6.1 ± 1.2 kg]) were used to determine the optimal dietary standardized ileal digestible (SID) arginine (Arg) level in early nursery diets based on growth and health responses. The basal diet in Exp.1 was formulated to meet SID Arg recommendation (0.66%; NRC, 2012) and in Exp. 2, SID Arg was set to simulate current industry practices for feeding nursery pigs (1.15 %). Basal diets were supplemented with 0.3%, 0.6%, 0.9%, and 1.2% of l-arginine to provide five levels of dietary SID Arg. Experimental diets were fed during phases I (days 0 to 7) and II (days 8 to 21) with common diets until market. Feed disappearance and body weight (BW) were measured on days 7, 14, 21, and 43. Final BW was recorded at first removal of pigs for market. Pen fecal score was assigned daily from days 0 to 21. Plasma immunoglobulin A (IgA) was determined on days 0, 7, and 14 and amino acids (AAs) concentration and plasma urea nitrogen (PUN) on days 0 and 14. Orthogonal polynomial contrasts were used to determine the linear and quadratic effects of dietary Arg. Optimal SID Arg was determined by fitting the data with piecewise regression, using growth performance as the primary response variable. In Exp. 1, dietary Arg linearly increased (P < 0.1) BW, average daily gain (ADG), and gain to feed ratio (G:F) ratio on day 21, as well as reduced (χ2 = 0.004) the percentage of pigs that lost weight (PLW) in week 1 by 29%. Dietary Arg resulted in linear improvement (P = 0.082) of ADG for the overall nursery period and quadratic improvement (P < 0.1) of final BW at marketing. In Exp. 2, dietary Arg linearly increased (P < 0.05) ADG and average daily feed intake (ADFI) in week 1, BW and ADFI (P < 0.1) on day 14, as well as reduced (χ2 ≤ 0.001) PLW in week 1. From days 0 to 21, G:F was improved quadratically (P < 0.1). Dietary Arg linearly increased (P < 0.1) ADG and BW on day 43. Dietary Arg supplementation decreased the incidence (χ2 < 0.05) of soft and watery feces during the first weeks after weaning and lower concentration of plasma IgA on days 7 and 14. Dietary Arg linearly and/or quadratically influenced plasma AA concentrations (P < 0.05), including an increase in Arg, Leu, Phe, Val, citrulline, ornithine, and PUN concentrations. Overall, weaned pigs exhibit optimal nursery growth performance and health when provided with dietary SID Arg ranging from 1.5% to 1.9%. This dietary range contributes to a reduction in the occurrence of fall-back pigs and improvements in final BW at marketing.

Probiotic Roles of Clostridium butyricum in Piglets: Considering Aspects of Intestinal Barrier Function

China, as the global leader in pork production and consumption, is faced with challenges in ensuring sustainable and wholesome growth of the pig industry while also guaranteeing meat food safety amidst the ban on antibiotics usage in animal feed. The focus of the pig industry lies in guaranteeing piglet health and enhancing overall production performance through nutrition regulation. Clostridium butyricum (C. butyricum), a new type of probiotic, possesses characteristics such as heat resistance, acid resistance, and bile-salt tolerance, meaning it has potential as a feed additive. Previous studies have demonstrated that C. butyricum has a probiotic effect on piglets and can serve as a substitute for antibiotics. The objective of this study was to review the probiotic role of C. butyricum in the production of piglets, specifically focusing on intestinal barrier function. Through this review, we explored the probiotic effects of C. butyricum on piglets from the perspective of intestinal health. That is, C. butyricum promotes intestinal health by regulating the functions of the mechanical barrier, chemical barrier, immune barrier, and microbial barrier of piglets, thereby improving the growth of piglets. This review can provide a reference for the rational utilization and application of C. butyricum in swine production.

Amino acids in piglet diarrhea: Effects, mechanisms and insights

Piglet diarrhea is among one of the most serious health problems faced by the pig industry, resulting in significant economic losses. Diarrheal disease in piglets has a multifactorial etiology that is affected by physiology, environment, and management strategy. Diarrhea is the most apparent symptom of intestinal dysfunction. As a key class of essential nutrients in the piglet diet, amino acids confer a variety of beneficial effects on piglets in addition to being used as a substrate for protein synthesis, including maintaining appropriate intestinal integrity, permeability and epithelial renewal, and alleviating morphological damage and inflammatory and oxidative stress. Thus, provision of appropriate levels of amino acids could alleviate piglet diarrhea. Most amino acid effects are mediated by metabolites, gut microbes, and related signaling pathways. In this review, we summarize the current understanding of dietary amino acid effects on gut health and diarrhea incidence in piglets, and reveal the mechanisms involved. We also provide ideas for using amino acid blends and emphasize the importance of amino acid balance in the diet to prevent diarrhea in piglets.

The impact of dietary Laminaria digitata and alginate lyase supplementation on the weaned piglet liver: A comprehensive proteomics and metabolomics approach

The brown seaweed Laminaria digitata, a novel feedstuff for weaned piglets, has potentially beneficial prebiotic properties. However, its recalcitrant cell wall challenges digestion in monogastrics. Alginate lyase is a promising supplement to mitigate this issue. This study's aim was to investigate the impact of incorporating 10% dietary Laminaria digitata, supplemented with alginate lyase, on the hepatic proteome and metabolome of weaned piglets. These diets introduced minor variations to the metabolome and caused significant shifts in the proteome. Dietary seaweed provided a rich source of n-3 PUFAs that could signal hepatic fatty acid oxidation (FABP, ACADSB and ALDH1B1). This may have affected the oxidative stability of the tissue, requiring an elevated abundance of GST for regulation. The presence of reactive oxygen species likely inflicted protein damage, triggering increased proteolytic activity (LAPTM4B and PSMD4). Alginate lyase supplementation augmented the number of differentially abundant proteins, which included GBE1 and LDHC, contributing to maintain circulating glucose levels by mobilizing glycogen stores and branched-chain amino acids. The enzymatic supplementation with alginate lyase amplified the effects of the seaweed-only diet. An additional filter was employed to test the effect of missing values on the proteomics analysis, which is discussed from a technical perspective. SIGNIFICANCE: Brown seaweeds such as Laminaria digitata have prebiotic and immune-modulatory components, such as laminarin, that can improve weaned piglet health. However, they have recalcitrant cell wall polysaccharides, such as alginate, that can elicit antinutritional effects on the monogastric digestive system. The aim of this study was to evaluate the effect of a high level of dietary L. digitata and alginate lyase supplementation on the hepatic metabolism of weaned piglets, using high throughput Omics approaches.

Enhancing Weaned Piglet Health and Performance: The Role of Autolyzed Yeast (Saccharomyces cerevisiae) and β-Glucans as a Blood Plasma Alternative in Diets

The objective of this study was to evaluate the inclusion of the autolyzed yeast (AY) Saccharomyces cerevisiae with or without an immunomodulator (1,3/1,6 β-glucans) as a total/partial substitute for blood plasma (BP) in the diet of post-weaning piglets; zootechnical performance, intestinal health and microbiota, immune responses and energy metabolism were assessed. A total of 240 castrated male and female piglets, with a mean age of 22 days and mean initial weight of 5.24 ± 0.82 kg, were randomly divided into blocks of four treatments with 12 replicates. The dietary inclusions were blood plasma (BP), autolyzed yeast (AY), autolyzed yeast + immunomodulator (AYI) and 50% BP and 50% AY (BPAY). In pre-initial phase II (29-35 days), piglets fed AY showed better feed conversion (FCR = 1.358) than the piglets in the BP (1.484), AYI (1.379) and BPAY (1.442) groups, i.e., 8.49% (0.126), 1.52% (0.021) and 4.50% (0.084), respectively (p = 0.0293). In the total period (21-42 days), better FCR was observed in the AYI (1.458) group, i.e., 4.64% (0.071), 1.15% (0.017) and 4.58% (0.070), than in the BP (1.529), AY (1.475) and BPAY (1.528) groups, respectively (p = 0.0150). In piglets fed AY (n = 3) and BPAY (n = 2), there was a reduction in the number of medications, i.e., 82.35% (-14n) and 88.23% (-15n), respectively (p = 0.0001), compared with that in the BP group (n = 17). In the AY group (73.83 mg/dL), AYI group (69.92 mg/dL), and BPAY group (69.58 mg/dL), piglets exhibited increases in triglyceride levels of 79.32%, 69.83%, and 69.00%, respectively, in comparison to those in the BP group, which had triglyceride levels of 41.17 mg/dL (p = 0.0400). The beta-hydroxybutyrate concentration in the AY group (79.96 ng/μL) was lower by 31.95%, 22.64%, and 5.89% compared to the BP group (117.50 ng/μL), AYI group (103.36 ng/μL), and BPAY group (84.67 ng/μL), respectively (p = 0.0072). In the AYI group, there was modulation of the microbiota, with an increase in the relative abundance of bacteria of the genera Lactobacillus, Collinsella and Bulleidia. AY, associated or not associated with an immunomodulator, is a potential substitute for BP in diets for piglets in the nursery phase, with positive effects on immune, metabolic, and intestinal microbial performance.

Effects of Dietary Supplementation with Tea Residue on Growth Performance, Digestibility, and Diarrhea in Piglets

Thirty-six healthy 21-day-old weaned ternary piglets (Duroc × Landrace × Yorkshire) were randomly divided into two treatments with 18 replicates per treatment and one pig per replicate. The control group was fed with a basal diet and the test group was fed with diets supplemented with 1 kg/t tea residue. The test period was 28 days. The results are as follows: The addition of tea residue in the diet had no significant effect on the growth performance of weaned piglets (p > 0.05), but it could significantly reduce the diarrhea rate of piglets from 1 to 7 days and 1 to 28 days (p < 0.05). Compared with the control group, the dietary supplementation of tea residue had no significant effect on nutrient apparent digestibility, plasma biochemical indexes and plasma immune indexes (p > 0.05) but increased the content of glutathione in plasma (p < 0.05). Tea residue had no significant effect on the morphology of the jejunum and ileum of piglets (p > 0.05), but it could significantly reduce the content of chloride ions in feces (p < 0.05). Compared with the basal diet group, there was no significant difference in the relative expression of TMEM16A and CFTR mRNA in the colon of weaned piglets (p > 0.05). The whole-cell patch clamp recording showed that the TMEM16A and CFTR ion channels could be activated by ionomycin and forskolin, respectively. However, when HT-29 cells transfected with TMEM16A and CFTR channels were treated with tea residue extract, it could significantly inhibit the chloride current of the TMEM16A and CFTR ion channels (p < 0.05).

Impact of precursor-derived peracetic acid on post-weaning diarrhea, intestinal microbiota, and predicted microbial functional genes in weaned pigs

Post-weaning diarrhea affects piglets in the nursery phase of production, leading to a substantial impact both at the farm and financial levels. The multifactorial etiology of this disease includes housing conditions, pig genetics, microbial composition, and metagenomic assets. Among the common therapeutic approaches, the widely used zinc oxide underwent a European Union ban in 2022 due to its negative environmental impact and correlation to increased antimicrobial resistance. During this study, we have tested two levels of inclusion of the potential antimicrobial alternative peracetic acid, delivered in water via the hydrolysis of the precursors sodium percarbonate and tetraacetylethylenediamine, in comparison to zinc oxide and an untreated control during a 2-week animal study. We assessed the microbial composition and predicted the metagenome, together with performance and physiological parameters, in order to describe the microbial functional role in etiopathology. Both zinc oxide and peracetic acid resulted in amelioration of the diarrheal status by the end of the trial period, with noticeable zinc oxide effects visible from the first week. This was accompanied by improved performance when compared to the first-week figures and a decreased stomach pH in both peracetic acid levels. A significant reduction in both stomach and caecal Proteobacteria was recorded in the zinc oxide group, and a significant reduction of Campylobacter in the stomach was reported for both zinc oxide and one of the peracetic acid concentrations. Among other functional differences, we found that the predicted ortholog for the zonula occludens toxin, a virulence factor present in pathogens like Escherichia coli and Campylobacter jejuni, was less abundant in the stomach of treated pigs compared to the control group. In water, peracetic acid delivered via precursor hydrolysis has the potential to be a valid intervention, an alternative to antimicrobial, to assist the weaning of piglets. Our findings support the view that post-weaning diarrhea is a complex multifactorial disease with an important metagenomic component characterized by the differential abundance of specific predicted orthologs and microbial genera in the stomach and caecum of pigs.

Detection of mcr-1-1 Positive Enteropathogenic Escherichia coli Isolates Associated with Post-Weaning Diarrhoea in an Organic Piglet-Producing Farm in Austria

Postweaning diarrhoea (PWD) is a frequent multifactorial disease occurring in swine stocks worldwide. Since pathogenic Escherichia (E.) coli play a pivotal role in the pathogenesis of PWD and porcine E. coli are often resistant to different antibiotics, colistin is frequently applied to treat piglets with PWD. However, the application of colistin to livestock has been associated with the emergence of colistin resistance. This case report describes the detection of the colistin resistance gene mcr-1-1 in two E. coli isolated from piglets with PWD in an Austrian organic piglet-producing farm, which was managed by two farmers working as nurses in a hospital. Both mcr-1-positive E. coli were further analysed by Illumina short-read-sequencing, including assemblies and gene prediction. Both isolates belonged to the same clonal type and were positive for eaeH and espX5, which are both virulence genes associated with enteropathogenic E. coli (EPEC). Due to the detection of mcr-1-positive EPEC and based on the results of the antimicrobial resistance testing, the veterinarian decided to apply gentamicin for treatment instead of colistin, leading to improved clinical signs. In addition, after replacing faba beans with whey, PWD was solely observed in 2/10 weaned batches in the consecutive months.

Pioneering gut health improvements in piglets with phytogenic feed additives

This research investigates the effects of phytogenic feed additives (PFAs) on the growth performance, gut microbial community, and microbial metabolic functions in weaned piglets via a combined 16S rRNA gene amplicon and shotgun metagenomics approach. A controlled trial was conducted using 200 pigs to highlight the significant influence of PFAs on gut microbiota dynamics. Notably, the treatment group revealed an increased gut microbiota diversity, as measured with the Shannon and Simpson indices. The increase in diversity is accompanied by an increase in beneficial bacterial taxa, such as Roseburia, Faecalibacterium, and Prevotella, and a decline in potential pathogens like Clostridium sensu stricto 1 and Campylobacter. Shotgun sequencing at the species level confirmed these findings. This modification in microbial profile was coupled with an altered profile of microbial metabolic pathways, suggesting a reconfiguration of microbial function under PFA influence. Significant shifts in overall microbial community structure by week 8 demonstrate PFA treatment's temporal impact. Histomorphological examination unveiled improved gut structure in PFA-treated piglets. The results of this study indicate that the use of PFAs as dietary supplements can be an effective strategy, augmenting gut microbiota diversity, reshaping microbial function, enhancing gut structure, and optimising intestinal health of weaned piglets providing valuable implications for swine production. KEY POINTS: • PFAs significantly diversify the gut microbiota in weaned piglets, aiding balance. • Changes in gut structure due to PFAs indicate improved resistance to weaning stress. • PFAs show potential to ease weaning stress, offering a substitute for antibiotics in piglet diets.

Exploring zinc deficiency using serum Zn levels: consequences and potential solutions in suckling pigs

Three trials were undertaken to provide an answer to different questions: 1) Are suckling pigs able to maintain physiological serum Zn levels throughout lactation and do these levels vary between high and low body weight (BW) pigs?, 2) Are serum Zn levels in pigs soon after weaning a predisposing factor for diarrhea?, and 3) Is it possible to increase serum Zn levels at weaning by supplementing Zn during lactation. In trial 1, blood samples were taken from pigs during lactation. Eight pigs (one piglet per litter) had blood drawn on days 0 (farrowing), 7, 14, 21, and 28 (weaning), and 60 pigs (selected from the whole farrowing batch with 35 sows), categorized as either heavy (8.63 kg) or light (5.50 kg) had blood drawn on day 28. Serum Zn levels at birth were 1.2 mg/L and decreased (P < 0.01) to 0.67 mg/L on day 28. Heavier pigs showed greater (P < 0.01) serum Zn levels (0.98 mg/L) than light BW pigs (0.79 mg/L). In trial 2, blood samples were obtained from 240 pigs at weaning (26.2 ± 2.5 d) with an average initial BW of 6.94 ± 1.87 kg and were distributed into 24 pens (10 pigs/pen) by BW. Diarrhea incidence was recorded daily from days 0 to 35 post-weaning. From the 240 pigs, a group of 110 pigs with uniform BW (6.5 ± 1.9 kg) was selected and separated into two groups based on serum Zn levels at weaning with 55 pigs with low serum Zn (LZn: <0.71 mg/L) and 55 pigs with high serum Zn (HZn: >0.9 mg/L). Pigs with LZn were 2.49 times as likely to have diarrhea as pigs with HZn (P < 0.02). In trial 3, a total of 96 suckling pigs were allotted four treatments that consisted of the daily administration of 0, 6, 18, or 30 mg of Zn as Zn citrate in capsule form during the last 7 d of lactation. Pigs were individually weighed, and blood samples were obtained on days 14, 21 (weaning), and 7 after weaning. Serum Zn levels linearly increased by day as Zn citrate supplementation increased (interaction, P < 0.001). However, only light pigs supplemented with 18 and 30 mg/L of Zn experienced an increase in serum Zn levels during lactation. In conclusion, a decrease in serum Zn levels occurs during lactation and is more severe in low BW pigs. Low Zn status (< 0.7 mg/L) at weaning may be a predisposing factor for diarrhea. However, Zn supplementation during lactation can mitigate this decrease in light pigs.

Synbiotics improve growth performance and nutrient digestibility, inhibit PEDV infection, and prevent intestinal barrier dysfunction by mediating innate antivirus immune response in weaned piglets

This experiment was conducted to explore the effects of dietary synbiotics (SYB) supplementation on growth performance, immune function, and intestinal barrier function in piglets challenged with porcine epidemic diarrhea virus (PEDV). Forty crossbred (Duroc × Landrace × Yorkshire) weaned piglets (26 ± 1 d old) with a mean body weight (BW) of 6.62 ± 0.36 kg were randomly allotted to five groups: control (CON) I and CONII group, both fed basal diet; 0.1% SYB group, 0.2% SYB group, and 0.2% yeast culture (YC) group, fed basal diet supplemented with 0.1%, 0.2% SYB, and 0.2% YC, respectively. On day 22, all piglets were orally administrated with 40 mL PEDV (5.6 × 103 TCID50/mL) except piglets in CONI group, which were administrated with the same volume of sterile saline. The trial lasted for 26 d. Before PEDV challenge, dietary 0.1% SYB supplementation increased final BW, average daily gain (ADG), and decreased the ratio of feed to gain during 0 to 21 d (P < 0.05), as well as improved the apparent nutrient digestibility of dry matter (DM), organic matter (OM), crude protein, ether extract (EE), and gross energy (GE). At the same time, 0.2% YC also improved the apparent nutrient digestibility of DM, OM, EE, and GE (P < 0.05). PEDV challenge increased diarrhea rate and diarrhea indexes while decreased ADG (P < 0.05) from days 22 to 26, and induced systemic and intestinal mucosa innate immune and proinflammatory responses, destroyed intestinal barrier integrity. The decrease in average daily feed intake and ADG induced by PEDV challenge was suppressed by dietary SYB and YC supplementation, and 0.1% SYB had the best-alleviating effect. Dietary 0.1% SYB supplementation also increased serum interleukin (IL)-10, immunoglobulin M, complement component 4, and jejunal mucosal IL-4 levels, while decreased serum diamine oxidase activity compared with CONII group (P < 0.05). Furthermore, 0.1% SYB improved mRNA expressions of claudin-1, zonula occludens protein-1, mucin 2, interferon-γ, interferon regulatory factor-3, signal transducers and activators of transcription (P < 0.05), and protein expression of occludin, and downregulated mRNA expressions of toll-like receptor 3 and tumor necrosis factor-α (P < 0.05) in jejunal mucosa. Supplementing 0.2% SYB or 0.2% YC also had a positive effect on piglets, but the effect was not as good as 0.1% SYB. These results indicated that dietary 0.1% SYB supplementation improved growth performance under normal conditions, and alleviated the inflammatory response and the damage of intestinal barrier via improving innate immune function and decreasing PEDV genomic copies, showed optimal protective effects against PEDV infection.

The Use of Fruit and Vegetable by-Products as Enhancers of Health Status of Piglets after Weaning: The Role of Bioactive Compounds from Apple and Carrot Industrial Wastes

At weaning, piglets are exposed to a large variety of stressors, from environmental/behavioral factors to nutritional stress. Weaning transition affects the gastrointestinal tract especially, resulting in specific disturbances at the level of intestinal morphology, barrier function and integrity, mucosal immunity and gut microbiota. All these alterations are associated with intestinal inflammation, oxidative stress and perturbation of intracellular signaling pathways. The nutritional management of the weaning period aims to achieve the reinforcement of intestinal integrity and functioning to positively modulate the intestinal immunity and that of the gut microbiota and to enhance the health status of piglets. That is why the current research is focused on the raw materials rich in phytochemicals which could positively modulate animal health. The composition analysis of fruit, vegetable and their by-products showed that identified phytochemicals could act as bioactive compounds, which can be used as modulators of weaning-induced disturbances in piglets. This review describes nutritional studies which investigated the effects of bioactive compounds derived from fruit (apple) and vegetables (carrot) or their by-products on the intestinal architecture and function, inflammatory processes and oxidative stress at the intestinal level. Data on the associated signaling pathways and on the microbiota modulation by bioactive compounds from these by-products are also presented.

Laminaria japonica Polysaccharides Improves the Growth Performance and Faecal Digestive Enzyme Activity of Weaned Piglets

The aim of this experiment was to investigate the effect of Laminaria japonica polysaccharide (LJP) supplementation at levels of 100, 200, or 400 mg/kg on the growth performance, faecal digestive enzyme activity, and serum biochemistry and amino acids of weaned piglets. One hundred and twenty weaned piglets (Barkshire × Licha Black, 21 days old, 6.13 ± 0.16 kg) were randomly divided into four groups with five replicates of six piglets in each group based on body weight. Piglets were fed with different levels (0, 100, 200, and 400 mg/kg) of LJP for a 21-day trial. On day 21, faecal and blood samples were collected from one piglet per pen. The results showed that the supplementation of the 200 and 400 mg/kg LJP significantly increased average daily gain (ADG) and average daily feed intake (ADFI) compared to the control group (p = 0.007; p = 0.002), and dietary LJP linearly increased ADG and ADFI (p = 0.002; p < 0.001). In addition, the supplementation of the 200 and 400 mg/kg LJP significantly increased faecal amylase activity (p < 0.001) compared to the control group, and dietary LJP linearly increased faecal amylase and lipase activities (p = 0.001; p = 0.037). Moreover, dietary LJP at 400 mg/kg increased serum histidine content compared to the other groups (p = 0.002), and dietary LJP linearly increased the contents of serum histidine and asparagine in piglets (p < 0.001; p = 0.046). In conclusion, supplementation of 200 and 400 mg/kg LJP could enhance growth performance and faecal digestive enzyme activity and modulate the serum amino acid content of weaned piglets, potentially contributing to the health of weaned piglets.

Nutritional Strategies to Mitigate Post-Weaning Challenges in Pigs: A Focus on Glucans, Vitamin D, and Selenium

This review examines the challenges faced by the pig industry, with a specific focus on improving the health and growth of weaned pigs. It emphasizes the immediate necessity of investigating alternative approaches to managing pig nutrition and health due to restrictions on the use of antibiotics and the prohibition of zinc oxide in weaned pig diets. The weaning phase is identified as a critical stage in piglet development, characterized by stressors that affect their gastrointestinal health, immune responses, and overall physiology. The primary challenge during weaning arises from transitioning piglets from a digestible milk-based diet to a less digestible cereal-based feed, causing nutritional stress. This manifests as reduced feed intake, leading to gastrointestinal disturbances, intestinal inflammation, and adverse effects on intestinal structure and microbiota. To address these challenges and optimize piglet development, various nutritional strategies have been explored. Notably, glucans, particularly β-glucans from fungi, cereals, algae, and yeast, show promise in alleviating weaning-related issues. Furthermore, it is important to highlight the critical roles played by Vitamin D and selenium in piglet nutrition. These essential nutrients can be sourced naturally from enriched mushrooms that are specifically enriched with Vitamin D and selenium, providing a sustainable dietary option. In conclusion, effective nutritional strategies, including glucans, Vitamin D, selenium, and enriched mushrooms, are beneficial for addressing weaning-related challenges.

Effect of Low Protein Diets Supplemented with Sodium Butyrate, Medium-Chain Fatty Acids, or n-3 Polyunsaturated Fatty Acids on the Growth Performance, Immune Function, and Microbiome of Weaned Piglets

This study aimed to investigate the effects of low-protein (LP) diets supplemented with sodium butyrate (SB), medium-chain fatty acids (MCT), or n-3 polyunsaturated fatty acids (n-3 PUFA) on the growth performance, immune function, and the microbiome of weaned piglets. A total of 120 healthy weaned piglets ((Landrace × Large White × Duroc); 7.93 ± 0.7 kg initial body weight), were randomly divided into five groups. Each group consisted of six replications with four piglets per replication. Dietary treatments included control diet (CON); LP diet (LP); LP + 0.2% SB diet (LP + SB); LP + 0.2% MCT diet (LP + MCT); and LP + PUFA diet (LP + PUFA). The experimental period lasted for 4 weeks. Compared with the CON diet, LP, LP + SB, LP + MCT, and LP + PUFA diets decreased the final weight and average daily gain (ADG) of piglets (p < 0.05). There were lower (p < 0.05) concentrations of IL-8 and higher (p < 0.05) Glutathione peroxidase (GSH-Px) activity in the plasma of piglets fed with LP + SB, LP + MCT, and LP + PUFA diets than those fed with the LP diet. The piglets in the LP + SB and LP + PUFA groups had lower IKK-alpha (IKKa) mRNA expression in the colonic mucosa compared with those in the CON and LP groups (p < 0.05). The mRNA expression of TLR4 in the colonic mucosa of piglets in the LP + SB, LP + MCT, and LP + PUFA groups was decreased when compared with the CON and LP groups (p < 0.05). The LP + MCT diets increased the gene expression of nuclear factor erythroid 2-related factor 2 (Nrf2) in the colonic mucosa of piglets compared with CON, LP, and LP + SB diets (p < 0.05). The abundance of Erysipelotrichaceae in the colonic microbiome of piglets in the LP group was higher than that in the other four groups (p < 0.05). Collectively, this study showed that LP diets supplemented with SB, MCT, or n-3 PUFA reduced plasma inflammatory factor levels, increased plasma GSH-Px activity, and declined mRNA expression of TLR4 and IKKa in the colonic epithelium, whereas it reduced the abundance of Erysipelotrichaceae in the colon of piglets.

Blend of natural and natural identical essential oil compounds as a strategy to improve the gut health of weaning pigs

Weaning is one of the most critical phases in pig's life, often leading to postweaning diarrhoea (PWD). Zinc oxide (ZnO), at pharmacological doses, has been largely used to prevent PWD; however, due to antimicrobial co-resistant and environmental pollution issues, the EU banned its use in June 2022. Natural or natural identical components of essential oils and their mixture with organic acids are possible alternatives studied for their antimicrobial, anti-inflammatory and antioxidant abilities. This study aimed to evaluate the effect of two blends of natural or natural identical components of essential oils and organic acids compared to ZnO on health, performance, and gut health of weaned pigs. At weaning (d0), 96 piglets (7 058 ± 895 g) were assigned to one of four treatments balanced for BW and litter: CO (control treatment), ZnO (2 400 mg/kg ZnO from d0 to d14); Blend1 (cinnamaldehyde, ajowan and clove essential oils, 1 500 mg/kg feed); Blend2 (cinnamaldehyde, eugenol and short- and medium-chain fatty acids, 2 000 mg/kg feed). Pigs were weighed weekly until d35. Faeces were collected at d13 and d35 for microbiota (v3-v4 regions of the 16 s rRNA gene) and Escherichia coli (E. coli) count analysis. At d14 and d35, eight pigs/treatment were slaughtered; pH was recorded on intestinal contents and jejunal samples were collected for morphological and gene expression analysis. From d7-d14, the Blend2 had a lower average daily gain (ADG) than CO and ZnO (P < 0.05). ZnO and Blend1 never differed in ADG and feed intake. At d14, ZnO had a lower caecum pH than all other treatments. The CO treatment had a higher abundance of haemolytic E. coli than Blend1 (P = 0.01). At d13, the ZnO treatment had a lower alpha diversity (P < 0.01) and a different microbial beta diversity (P < 0.001) compared to the other treatments. At d13, the ZnO treatment was characterised by a higher abundance of Prevotellaceae_NK3B31_group (Linear Discriminant Analysis (LDA) score = 4.5, P = 0.011), Parabacteroides (LDA score = 4.5, P adj. = 0.005), the CO was characterised by Oscillospiraceae UCG-005 (LDA score = 4.3, P adj. = 0.005), Oscillospiraceae NK4A214_group (LDA score = 4.2, P adj. = 0.02), the Blend2 was characterised by Megasphaera (LDA score = 4.1, P adj. = 0.045), and Ruminococcus (LDA score = 3.9, P adj. = 0.015) and the Blend1 was characterised by Christensenellaceae_R-7_group (LDA score = 4.6, P adj. < 0.001) and Treponema (LDA score = 4.5, P adj. < 0.001). In conclusion, Blend1 allowed to maintain the gut health of postweaning piglets through modulation of the gut microbiome, the reduction of haemolytic E. coli while Blend2 did not help piglets.

Replacing dietary sodium selenite with biogenic selenium nanoparticles improves the growth performance and gut health of early-weaned piglets

Selenium nanoparticles (SeNPs) are proposed as a safer and more effective selenium delivery system than sodium selenite (Na2SeO3). Here, we investigated the effects of replacing dietary Na2SeO3 with SeNPs synthesized by Lactobacillus casei ATCC 393 on the growth performance and gut health of early-weaned piglets. Seventy-two piglets (Duroc × Landrace × Large Yorkshire) weaned at 21 d of age were divided into the control group (basal diet containing 0.3 mg Se/kg from Na2SeO3) and SeNPs group (basal diet containing 0.3 mg Se/kg from SeNPs) during a 14-d feeding period. The results revealed that SeNPs supplementation increased the average daily gain (P = 0.022) and average daily feed intake (P = 0.033), reduced (P = 0.056) the diarrhea incidence, and improved (P = 0.013) the feed conversion ratio compared with Na2SeO3. Additionally, SeNPs increased jejunal microvilli height (P = 0.006) and alleviated the intestinal barrier dysfunction by upregulating (P < 0.05) the expression levels of mucin 2 and tight junction proteins, increasing (P < 0.05) Se availability, and maintaining mitochondrial structure and function, thereby improving antioxidant capacity and immunity. Furthermore, metabolomics showed that SeNPs can regulate lipid metabolism and participate in the synthesis, secretion and action of parathyroid hormone, proximal tubule bicarbonate reclamation and tricarboxylic acid cycle. Moreover, SeNPs increased (P < 0.05) the abundance of Holdemanella and the levels of acetate and propionate. Correlation analysis suggested that Holdemanella was closely associated with the regulatory effects of SeNPs on early-weaned piglets through participating in lipid metabolism. Overall, replacing dietary Na2SeO3 with biogenic SeNPs could be a potential nutritional intervention strategy to prevent early-weaning syndrome in piglets.

Piglet growth performance improved by dietary supplementation of porous or nano particles of zinc oxide may be related to the gut microbiota

Previous studies on porous or nano particles zinc oxide (ZnO) in the piglets have mainly focused on growth performance and intestinal inflammation, but have scarcely explored the efficacy on gut microbiota. In addition, the efficacy of nano particles ZnO, which is related to its product quality, remains undefined. This study aimed to determine the efficacy of dietary 500 mg/kg porous or nano particles ZnO on the growth performance and gut microbiota of the weaned piglets. A total of 128 weaned piglets were randomly assigned to the dietary groups: NC (basal diet), PC (basal diet + 3,000 mg/kg conventional ZnO), 500HiZ (basal diet + 500 mg/kg porous particles ZnO), and 500ZNP (basal diet + 500 mg/kg nano particles ZnO). Compared with the NC diet group, both 500HiZ and 500ZNP increased (P < 0.05) average daily feed intake (1 to 28 d) and average daily gain (1 to 28 d), and the 500ZNP tended to decrease feed to gain ratio (F:G ratio, 1 to 28 d) (P = 0.09). Both 500HiZ and 500ZNP decreased crypt depth of the ileum and increased claudin-2 in the duodenum and zonula occludens-1 in the ileum (P < 0.05). Moreover, both 500HiZ and 500ZNP decreased IL-1β and tumor necrosis factor-α (TNF-α) in the jejunum and decreased TNF-α and IL-6 in the ileum (P < 0.05). Both 500HiZ and 500ZNP increased microbial β-diversity index in the ileum and microbial α-diversity indices in the colon of piglets (P < 0.05). The probiotic genera Coprococcus (500ZNP) and Blautia (500HiZ) were positively correlated with the F:G ratio (1 to 28 d) in colon of piglets (P < 0.05). In addition, 500HiZ promoted mitochondrial fusion protein 1 (MFN1) and zinc transporter-1 (ZnT-1) in the jejunum (P < 0.05), whilst 500ZNP decreased MFN1 in the jejunum and ZnT-1 in the ileum (P < 0.05). In summary, both 500HiZ and 500ZNP improved the growth performance of piglets, which is likely via the genera Blautia and Coprococcus, respectively. Both 500HiZ and 500ZNP improved barrier function and inflammation of the intestine, and 500HiZ achieved better efficacy than 500ZNP on intestine mitochondrial functions.

Enhanced ileum function in weaned piglets via Laminaria digitata and alginate lyase dietary inclusion: A combined proteomics and metabolomics analysis

Laminaria digitata, a brown seaweed with prebiotic properties, can potentially enhance the resilience of weaned piglets to nutritional distress. However, their cell wall polysaccharides elude digestion by monogastric animals' endogenous enzymes. In vitro studies suggest alginate lyase's ability to degrade such polysaccharides. This study aimed to assess the impact of a 10% dietary inclusion of L. digitata and alginate lyase supplementation on the ileum proteome and metabolome, adopting a hypothesis-generating approach. Findings indicated that control piglets escalated glucose usage as an enteric energy source, as evidenced by the increased abundance of PKLR and PCK2 proteins and decreased tissue glucose concentration. Additionally, the inclusion of seaweed fostered a rise in proteins linked to enhanced enterocyte structural integrity (ACTBL2, CRMP1, FLII, EML2 and MYLK), elevated peptidase activity (NAALADL1 and CAPNS1), and heightened anti-inflammatory activity (C3), underscoring improved intestinal function. In addition, seaweed-fed piglets showed a reduced abundance of proteins related to apoptosis (ERN2) and proteolysis (DPP4). Alginate lyase supplementation appeared to amplify the initial effects of seaweed-only feeding, by boosting the number of differential proteins within the same pathways. This amplification is potentially due to increased intracellular nutrient availability, making a compelling case for further exploration of this dietary approach. SIGNIFICANCE: Pig production used to rely heavily on antibiotics and zinc oxide to deal with post-weaning stress in a cost-effective way. Their negative repercussions on public health and the environment have motivated heavy restrictions, and a consequent search for alternative feed ingredients/supplements. One of such alternatives is Laminaria digitata, a brown seaweed whose prebiotic components that can help weaned piglets deal with nutritional stress, by improving their gut health and immune status. However, their recalcitrant cell walls have antinutritional properties, for which alginate lyase supplementation is a possible solution. By evaluating ileal metabolism as influenced by dietary seaweed and enzyme supplementation, we aim at discovering how the weaned piglet adapts to them and what are their effects on this important segment of the digestive system.

Pre-Treatment with Bromelain Prevents Intestinal Dysbiosis in Pigs with Post-Weaning Diarrhea, without Increasing Antimicrobial Resistance in Escherichia coli

Pigs are especially vulnerable to intestinal pathogens and dysbiosis in the first two weeks after weaning. Infection with enterotoxigenic strains of Escherichia coli (ETEC) in combination with poor nutrition and hygiene can lead to diarrhea, poor growth and increased mortality. While neomycin and zinc oxide can prevent post-weaning diarrhea (PWD), their broad-spectrum activity also kills commensal microbiota and can lead to the emergence of heavy metal and antimicrobial resistance. Bromelain prevents attachment of F4 ETEC to intestinal enterocytes by cleaving the host receptor. In controlled environmental facilities, weaned pigs treated with either therapeutic levels of neomycin sulfate, zinc oxide, bromelain or non-treated were monitored for diarrhea, weight gain, feed intake, feed efficiency, excretion of F4 ETEC, changes to their intestinal microbiomes and antimicrobial resistance in E. coli. The treatment effects were evaluated at weaning, during two weeks of treatment and for three weeks after treatments ceased. Minimal clinical signs of PWD were observed, except in zinc-treated pigs post treatment. Intestinal dysbiosis was observed in response to diarrhea and in pigs treated with both neomycin and zinc. Antimicrobial resistance increased in commensal E. coli isolated from neomycin- and zinc-treated pigs. In contrast, bromelain controlled PWD and prevented intestinal dysbiosis without inducing antimicrobial resistance.

Dietary supplementation with olive oil co-products rich in polyphenols: a novel nutraceutical approach in monogastric animal nutrition

In recent years, the increased demand for agri-food products to feed livestock species has stimulated research to identify novel solutions for the valorization of natural waste, according to the modern concept of a circular economy. Numerous studies have shown the use of plant-derived and agro-industrial co-products that are sources of bioactive molecules for preparing animal feeds. Supplementation with co-products derived from the extraction of olive oil (i.e., olive pomace, olive mill wastewater, olive cake and olive leaf) in diet has been widely considered in recent decades, because these wastes are produced in high quantity and their re-use represents an innovative economic and environmental strategy. Olive oil co-products are characterized by various bioactive molecules such as polyphenols, carbohydrates, proteins, and lipids. Among them, polyphenols are the nutraceuticals most studied, showing to promote health effects in both humans and animals. Olive oil co-products and their phenolic extracts have shown many beneficial and promising effects when added to the diets of monogastric animals, by improving performance parameters and maintaining the oxidative status of meat and derived products. This review provides an update on the use of olive co-products in monogastric animal (swine, poultry and rabbit) diets and their effects on the productive performance, meat quality characteristics and gut health status.

Dietary supplementation of zinc oxide modulates intestinal functionality during the post-weaning period in clinically healthy piglets

BACKGROUND

To improve our understanding of host and intestinal microbiome interaction, this research investigated the effects of a high-level zinc oxide in the diet as model intervention on the intestinal microbiome and small intestinal functionality in clinically healthy post-weaning piglets. In study 1, piglets received either a high concentration of zinc (Zn) as zinc oxide (ZnO, Zn, 2,690 mg/kg) or a low Zn concentration (100 mg/kg) in the diet during the post weaning period (d 14-23). The effects on the piglet's small intestinal microbiome and functionality of intestinal tissue were investigated. In study 2, the impact of timing of the dietary zinc intervention was investigated, i.e., between d 0-14 and/or d 14-23 post weaning, and the consecutive effects on the piglet's intestinal functionality, here referring to microbiota composition and diversity and gene expression profiles.

RESULTS

Differences in the small intestinal functionality were observed during the post weaning period between piglets receiving a diet with a low or high concentration ZnO content. A shift in the microbiota composition in the small intestine was observed that could be characterized as a non-pathological change, where mainly the commensals inter-changed. In the immediate post weaning period, i.e., d 0-14, the highest number of differentially expressed genes (DEGs) in intestinal tissue were observed between animals receiving a diet with a low or high concentration ZnO content, i.e., 23 DEGs in jejunal tissue and 11 DEGs in ileal tissue. These genes are involved in biological processes related to immunity and inflammatory responses. For example, genes CD59 and REG3G were downregulated in the animals receiving a diet with a high concentration ZnO content compared to low ZnO content in both jejunum and ileum tissue. In the second study, a similar result was obtained regarding the expression of genes in intestinal tissue related to immune pathways when comparing piglets receiving a diet with a high concentration ZnO content compared to low ZnO content.

CONCLUSIONS

Supplementing a diet with a pharmaceutical level of Zn as ZnO for clinically healthy post weaning piglets influences various aspects intestinal functionality, in particular in the first two weeks post-weaning. The model intervention increased both the alpha diversity of the intestinal microbiome and the expression of a limited number of genes linked to the local immune system in intestinal tissue. The effects do not seem related to a direct antimicrobial effect of ZnO.

The effects of using multi-species probiotics in late-pregnant and lactating sows on milk quality and quantity, fecal microflora, and performance of their offspring

Background and Aim

The dietary probiotics in sows during gestation to lactation period have gained considerable attention with respect to their beneficial effects on sows and their piglets' performance and health. This study aimed to evaluate the effects of using probiotics in late-pregnant and lactating sows on milk quality, quantity, fecal microflora of sows, and growth performance of their offspring until weaning.

Materials and Methods

Thirty-four sows were equally divided into two groups (control and treatment). Only those in the treatment group were fed 5 g of probiotics at 12 weeks of pregnancy, once daily for 7 weeks, until their piglets were weaned. Colostrum samples were collected at 3, 6, 12, and 24 h after farrowing and measured for immunoglobulin concentration. Percentages of fat, protein, and lactose in colostrum, colostrum production, total intake of immunoglobulin A (IgA), immunoglobulin G (IgG), fat, protein, and lactose, the change of fecal microflora of sows, and average daily gain of piglets were measured.

Results

The results showed that there were no significant differences in the concentrations of IgA, IgG, and IgM in colostrum and the percentages of fat, protein, lactose, solid-not-fat, and total solid in colostrum between the groups; however, the colostrum production at 24 h in the treatment group (6,075.29 mL) was higher than in the control group (4,809.54 mL). Higher total intakes of IgA and IgG as well as total intake of fat, protein, and lactose, particularly at 3 h after farrowing, were found in the treatment group. Probiotic supplementation remarkably altered the microbiota community at the phylum level. We found that Firmicutes and Bacteroidetes are the dominant phyla, present in the gut of more than 90% of pregnant and lactating sows. Changes in microbial proportions were observed due to the changes of pig production stage. The weaning weight of the treatment group was higher than in the control group (6.34 ± 1.71 vs. 4.84 ± 1.29 kg, respectively).

Conclusion

Feeding of multi-species probiotic BACTOSAC-P™ during late pregnancy and lactation in sows positively influenced colostrum production. In this experiment, the use of BACTOSAC-P™ improved the yield of colostrum production. The high immunoglobulin concentration and high yield of the colostrum of sows with a diet supplemented with BACTOSAC-P™ significantly reduced piglet mortality during the suckling period. Furthermore, the probiotic diet induced changes in the fecal microbial population in sows by increasing the number of microorganisms from the Firmicutes phylum, which had positive effects on sow health and their piglets, leading to better piglet growth performance.

Efficacy of Different Encapsulation Techniques on the Viability and Stability of Diverse Phage under Simulated Gastric Conditions

Salmonella causes a range of diseases in humans and livestock of considerable public health and economic importance. Widespread antimicrobial use, particularly in intensively produced livestock (e.g., poultry and pigs) may contribute to the rise of multidrug-resistant Salmonella strains. Alternative treatments such as bacteriophages have shown promise when used to reduce the intestinal carriage of Salmonella in livestock. However, the digestive enzymes and low pH encountered in the monogastric GI tract can significantly reduce phage viability and impact therapeutic outcomes. This study deployed alginate-carrageenan microcapsules with and without CaCO3 to protect a genomically diverse set of five Salmonella bacteriophages from simulated gastrointestinal conditions. None of the unprotected phage could be recovered following exposure to pH < 3 for 10 min. Alginate-carrageenan encapsulation improved phage viability at pH 2-2.5 after exposure for 10 min, but not at pH 2 after 1 h. Including 1% (w/v) CaCO3 in the formulation further reduced phage loss to <0.5 log10 PFU/mL, even after 1 h at pH 2. In all cases, phage were efficiently released from the microcapsules following a shift to a neutral pH (7.5), simulating passage to the duodenum. In summary, alginate-carrageenan-CaCO3 encapsulation is a promising approach for targeted intestinal delivery of genomically diverse Salmonella bacteriophages.

Evaluation of protected benzoic acid on growth performance, nutrient digestibility, and gut health indices in starter pigs

Benzoic acid is a common alternative for antibiotic and zinc oxide use in nursery diets. Free benzoic acid (BZA) is often supplied, but this form is absorbed before it can exert any effect on distal segments of the gut. The study aimed to evaluate the effects of protected benzoic acid on growth performance, nutrient digestibility, plasma metabolites, and gut health indices in starter pigs. A total of 192 pigs were weaned at 28 ± 1 d age (initial body weight, 8.72 ± 1.13 kg). Pens were assigned to one of four treatment diets (n = 8 pens per treatment): (1) no additive (NC), (2) free benzoic acid (BZA; 0.6%), (3) protected benzoic acid (BC50; 0.2%, supplied at a ratio of one to three equivalents of BZA), and (4) antibiotic growth promoter (AGP; Carbadox, 50 ppm). Diets were fed for three weeks over two periods (period 1, 7 d; period 2, 14 d). Body weight and feed intake were measured for each period. Feces were collected at the end of each period to determine apparent total tract digestibility (ATTD) of organic matter (OM), gross energy (GE), and crude protein (CP). One pig per pen was euthanized per period to determine plasma metabolites; jejunum and ileum morphology; jejunum, ileum, and colon cytokine abundance; and jejunum, ileum, and colon tight junction protein expression. The AGP group had increased average daily gain (ADG) and average daily feed intake (ADFI) compared to other groups in period 1 and overall (P < 0.05); however, ADG and ADFI of the BC50 group was intermediate between the NC and BZA groups and the AGP group in period 2. The ATTD of OM, GE, and CP were greater in the AGP group compared to the NC and BC50 groups (P < 0.05), whereas the BZA group was intermediate. Jejunum and ileum villus height and crypt depth increased from period 1 to period 2 (P < 0.01) but were similar across groups. Ileum and colon tumor necrosis factor-α (TNF-α) abundances were greater, whereas colon interleukin (IL)-1β and colon and ileum IL-8 abundances were less, in the AGP group compared to the BZA group (P < 0.05); the NC and BC50 groups exhibited intermediate TNF-α, IL-1β, and IL-8 abundance in the ileum and colon. Jejunum cytokine abundance did not vary among groups but declined from period 1 to period 2 (P < 0.05). Tight junction protein expression also did not vary among groups. In summary, protected BZA supported a slight increase in growth performance in starter pigs, suggesting its potential as an alternative feed additive in nursery diets.

Dietary emodin alleviates lipopolysaccharide-induced intestinal mucosal barrier injury by regulating gut microbiota in piglets

This study was to determine the effects of dietary emodin (ED) on the intestinal mucosal barrier, nuclear factor kappa-B (NF-κB) pathways, and gut microbial flora in lipopolysaccharide (LPS)-induced piglets. Twenty-four weaned piglets were chosen and 4 treatments were created by randomly distributing piglets into CON, ED, LPS, and ED_LPS groups. Experiments were done in a 2 × 2 factorial arrangement and maintained for 21 d. Dietary treatment (a basal diet or 300 mg/kg ED) and immunological challenge (LPS or sterile saline) were 2 major factors. Intraperitoneal injections of LPS or sterilized saline were given to piglets on d 21. Six hours after the LPS challenge, all piglets were euthanized for sample collection and analysis. The results showed that piglets of the ED_LPS group had higher (P < 0.05) villus height to crypt depth ratio (VCR), and lower (P < 0.05) plasma D-lactate and diamine oxidase (DAO) than the LPS group. Furthermore, ED inhibited (P < 0.05) the decrease of glutathione peroxidase (GSH-Px) and catalase (CAT) activities and increase of malonaldehyde level (P < 0.05) in jejunal mucosa induced by LPS. The mRNA levels of pro-inflammatory cytokine genes (IL-6, IL-1β, and TNF-α) were significantly reduced (P < 0.05), and the mRNA levels of antioxidant enzyme genes (GPX-1, SOD2 and CAT), as well as protein and mRNA levels of tight junction proteins (occludin, claudin-1, and ZO-1), were also significantly increased (P < 0.05) by ED addition in LPS-induced piglets. Meanwhile, ED supplementation significantly decreased the LPS-induced protein levels of cyclooxygenase-2 and phosphorylation levels of NF-κB p65 and IκBα in jejunal mucosa. Emodin had a significant effect on the composition of gut microbial flora at various taxonomic positions as indicated by 16S RNA sequencing. The acetic acid, isobutyric acid, valeric acid, and isovaleric acid concentrations in the cecum were also increased by ED addition in pigs (P < 0.05). Furthermore, the correlation analysis revealed that some intestinal microbiota had a potential relationship with jejunal VCR, plasma D-lactate and DAO, jejunal mucosa GSH-Px and CAT activity, and cecal short-chain fatty acid concentration. These data suggest that ED is effective in alleviating LPS-induced intestinal mucosal barrier injury by modulating gut microbiota in piglets.

Microbiome-Metabolomic Analysis Reveals Beneficial Effects of Dietary Kelp Resistant Starch on Intestinal Functions of Hybrid Snakeheads (Channa maculata ♀ × Channa argus ♂)

The benefits of resistant starch on hypoglycemia, obesity prevention, antioxidant status and the alleviation of metabolic syndrome have received considerable attention. In this study, we explored how dietary kelp resistant starch (KRS) enhances intestinal morphology and function through a microbiome-metabolomic analysis. Hybrid snakeheads (initial weight: 11.4 ± 0.15 g) were fed experimental diets for 60 days. Fish were fed a basic wheat starch diet and the KRS diet. Dietary KRS improved intestinal morphology and enhanced intestinal antioxidant and digestive capabilities, as evidenced by decreased intestinal damage and upregulated intestinal biochemical markers. The microbiome analysis showed that KRS administration elevated the proportion of butyrate-producing bacteria and the abundance of beneficial bacteria that increases insulin sensitivity. Furthermore, significant alterations in metabolic profiles were observed to mainly associate with the amino acid metabolism (particularly arginine production), the metabolism of cofactors and vitamins, fat metabolism, glutathione metabolism, and the biosynthesis of other secondary metabolites. Additionally, alterations in intestinal microbiota composition were significantly associated with metabolites. Collectively, changes in intestinal microbiota and metabolite profiles produced by the replacement of common starch with dietary KRS appears to play an important role in the development of intestinal metabolism, thus leading to improved intestinal function and homeostasis.

Effect of postweaning feed intake on performance, intestinal morphology, and the probability of diarrhoea in piglets

Changes in gastrointestinal architecture, high incidence of diarrhoea, and low feed intake (FI) are commonly observed around weaning of pigs, but the relationship between postweaning FI and diarrhoea is unclear. This study aimed to determine the effect of low or high FI during the first days after weaning on growth performance, diarrhoea probability, intestinal permeability, and morphology in pigs until postweaning day (PWD) 28. A total of 120 pigs (7.20 ± 0.26 kg) weaned at 28 days of age (PWD 0) were randomly allocated to five diets and housed individually until PWD 28. Two diets differed in CP and three diets differed in threonine and tryptophan levels. At PWD 4, pigs with the 25% lowest accumulated FI (LOW; n = 30) and 25% highest accumulated FI (HIGH; n = 30) were selected for the study. Faecal consistency was evaluated daily using a 4-scale visual scoring system. Blood was collected at PWD 4, 14, 21 and 28, and small intestinal and colonic tissue was obtained at slaughter on PWD 28. Until PWD 4, LOW pigs consumed approximately 20% (35.7 ± 5.9 g/day) of the FI of HIGH pigs (181 ± 5.75 g/day; P < 0.05) and their average daily gain (ADG) was -103 ± 15.1 g/day. At PWD 28, average daily feed intake, ADG, and feed conversion ratio were still negatively affected by the FI level (P < 0.05) and pigs in the LOW group were on average 4.4 kg lighter than HIGH pigs. Pigs in the HIGH group showed a 55% higher probability of diarrhoea compared with LOW pigs during PWD 0-28. The number of antibiotic treatment days against diarrhoea was 2.38 days higher for HIGH compared with LOW pigs (P = 0.04). The intestinal permeability markers diamine oxidase and D-lactate in plasma were unaffected by the level of FI (P > 0.10). The systemic inflammatory markers haptoglobin and C-reactive protein were higher for HIGH pigs at PWD 4 (P = 0.005), but not affected in the following periods (P > 0.10). Pigs in the HIGH group had an increased area of acidic mucin-producing cells in the small intestine compared with LOW pigs (P < 0.05), but other intestinal morphology measurements at PWD 28 were unaffected by the level of FI. In conclusion, high FI just after weaning was associated with higher growth performance but also higher probability of diarrhoea and more frequent use of antibiotics until PWD 28.

Identification of the gut microbiota affecting Salmonella pullorum and their relationship with reproductive performance in hens

Introduction

Pullorum disease is one of the common bacterial infectious diseases caused by Salmonella pullorum (S. pullorum), which can result in a decrease in the reproductive performance of laying hens, thus causing considerable economic losses. However, studies about the characteristics of intestinal microbiota with pullorum and their potential association with reproductive performance in hens are still limited. This study was to identify the gut microbiota associated with S. pullorum in poultry.

Methods

A total of 30 hens with S. pullorum-negative (PN) and 30 hens with S. pullorum-positive (PP) were analyzed for hatching eggs laid in 2 weeks (HEL), fertilization eggs (FE), chick number (CN), and microbial structure.

Results

There were significant differences in HEL (p < 0.01), FE (p < 0.01), and CN (p < 0.01) between PP and PN. Histomorphological observations showed abnormal morphology of the ovaries and fallopian tubes and low integrity of epithelial tissue in the ileum and cecum in PP. 16S rRNA gene sequencing revealed that beneficial cecal microbes, such as Bacteroides, Desulfovibrio, and Megamonas, were positively correlated with reproductive performance and had lower abundance in PP (p = 0.001). Furthermore, diminished phosphotransferase system (PTS) and pentose phosphate pathway, butanoate metabolism and oxidative phosphorylation were also found in PP.

Discussion

Taken together, this study clarified the morphological characteristics of the reproductive tract and intestines of chickens infected with S. pullorum and preliminarily explored the potential association between cecal microbiota and reproductive performance in hens. Our data may provide a reference for revealing the intestinal microbial characteristics of hens in resisting pullorum and exploring novel approaches to infection control in future studies.

Effects of glutamine, glutamate, and aspartate on intestinal barrier integrity and amino acid pool of the small intestine in piglets with normal or low energy diet

Aspartate (asp), glutamate (glu), and glutamine (gln) are the major energy fuels for the small intestine, and it had been indicated in our previous study that the mix of these three amino acid supplementations could maintain intestinal energy homeostasis. This study aimed to further investigate whether the treatment of gln, glu, and asp in low energy diet affects the intestinal barrier integrity and amino acid pool in weaning piglets. A total of 198 weaned piglets were assigned to 3 treatments: control (basal diet + 1.59% L-Ala); T1 (basal diet + 1% L-Gln + 0.5% L-Glu + 0.1% L-Asp); and T2 (low energy diet + 1% L-Gln + 0.5% L-Glu + 0.1% L-Asp). The blood, jejunum, and ileum were obtained on day 5 or on day 21 post-weaning, respectively. Our results showed that T1 and T2 treatments increased the abundances of occludin, claudin-1, and claudin-3 in the small intestine while decreasing the serum diamine oxidase (DAO) and D-lactate levels in weaning piglets. Meanwhile, T1 and T2 treatments significantly increased the positive rate of proliferating cell nuclear antigen (PCNA) of the small intestine, promoting intestinal cell proliferation. We also found that supplementation with glu, gln, and asp improved the serum amino acid pool and promoted ileal amino acid transporter gene expression of slc3a2, slc6a14, and slc7a11 in weaned piglets. Additionally, on day 21 post-weaning, T1 and T2 treatments stimulated the phosphorylation of the mTOR-S6K1-4EBP1 signaling pathway in the small intestine, which may implicate the enhanced protein synthesis rate. In summary, dietary supplementation of gln, glu, and asp was beneficial to the intestinal barrier function and amino acid pool regulation, while the benefits of gln, glu, and asp treatment might be diminished by the low-energy diet. The results demonstrated that the supplementation of gln, glu, and asp under low energy levels was preferentially supplied as the energy fuel to restore the gut barrier function in piglets on day 5 post-weaning. With the increase in age and intestinal maturation (on day 21 post-weaning), gln, glu, and asp supplementation could also show an effect on the regulation of the amino acid pool and protein synthesis.

Selected Nutrition and Management Strategies in Suckling Pigs to Improve Post-Weaning Outcomes

Weaning is a critical period in a pig's life. Piglets are confronted with abrupt changes to their physical and social environment, as well as management and nutritional changes. Weaning has always been associated with a growth check and is frequently accompanied by post-weaning diarrhoea in piglets. However, rapid increases in litter size in the last decade have increased within-litter piglet weight variation, with piglets now generally lighter at weaning, making the challenges associated with weaning even greater. Many interventions can be employed during the suckling period to ease the weaning transition for piglets. Pre-weaning strategies such as supervised farrowing (assistance with suckling and oxytocin provision), the provision of pain relief to sows around farrowing, split-suckling, early oral supplementation with glucose, bovine colostrum, faecal microbiota transplantation, feed additives and solid and liquid creep feeding (milk and liquid feed) have all been investigated. The objective of these strategies is to stimulate earlier maturation of the digestive tract, improve immunity, reduce latency to the first feed post-weaning and increase early post-weaning feed intake and growth. This review focuses in particular on: (1) pain relief provision to sows around farrowing, (2)split-suckling of piglets, (3) pre-weaning provision of supplementary milk and/or liquid feed, (4) other strategies to stimulate earlier enzyme production (e.g., enzyme supplementation), (5) other nutritional strategies to promote improved gut structure and function (e.g., L-glutamine supplementation), and (6) other strategies to modulate gut microbiota (e.g., probiotics and prebiotics). Correctly implementing these strategies can, not only increase post-weaning growth and reduce mortality, but also maximise lifetime growth in pigs.

Effects of Lacticaseibacillus casei (Lactobacillus casei) and Saccharomyces cerevisiae mixture on growth performance, hematological parameters, immunological responses, and intestinal microbiome in weaned pigs

Introduction

This study was conducted to evaluate the effects of Lacticaseibacillus casei (Lactobacillus casei) and Saccharomyces cerevisiae mixture on growth performance, hematological parameters, immunological responses, and gut microbiome in weaned pigs.

Methods

A total of 300 crossbred pigs [(Landrace × Yorkshire] × Duroc; 8.87 ± 0.34  kg of average initial body weight [BW]; 4  weeks of age) were divided into two dietary treatments (15 pigs/pen, 10 replicates/treatment) using a randomized complete block design (block = BW): control (CON) and the effective microorganism (MEM). The CON was not treated, while the MEM was treated with the mixture of L. casei (1 × 10⁷ CFU/mL) and S. cerevisiae (1 × 10⁷ CFU/mL) at 3 mL/pig/day for 4  weeks via the drinking water supply. Two feces and one blood sample from the randomly selected pigs in each pen were collected on D1 and D28 after weaning. Pigs were individually weighed, and pen feed intakes were recorded to evaluate pig growth performance. For the gut microbiome analysis, 16S rRNA gene hypervariable regions (V5 to V6) were sequenced using the Illumina MiSeq platform, and Quantitative Insight into Microbial Ecology (QIIME) and Microbiome Helper pipeline were used for 16S rRNA gene sequence analysis.

Results and Discussion

The daily weight gain and feed efficiency of MEM were significantly higher than those of CON (p < 0.001). There were no significant differences in hematological parameters and immune responses between CON and MEM. However, MEM had significantly lower Treponema genus, whereas significantly higher Lactobacillus and Roseburia genera compared to CON. Overall, our data showed that L. casei and S. cerevisiae mixture could promote growth performance through the modulation of gut microbiota in pigs. This study will help to understand the correlation between the growth performance and the gut microbiome.

The synbiotic mixture of lactulose and Bacillus coagulans protects intestinal barrier dysfunction and apoptosis in weaned piglets challenged with lipopolysaccharide

BACKGROUND

Lactulose as an effective prebiotic protects intestinal mucosal injury. Bacillus coagulans is widely used in feed additives because of its ability to promote intestinal health. Our previous study suggests that the combination of lactulose and Bacillus coagulans may be a good candidate as alternative for antibiotic growth promoters. However, the in vivo effects of lactulose and Bacillus coagulans on growth and intestinal health under immune challenge in piglets remains unclear. The objective of this study is to explore the protective effects of synbiotic containing lactulose and Bacillus coagulans on the intestinal mucosal injury and barrier dysfunction under immune challenge in weaned piglets.

METHODS

Twenty four weaned piglets were assigned to 4 groups. Piglets in the CON_-saline and LPS_-LPS group were fed the basal diet, while others were fed either with chlortetracycline (CTC) or synbiotic mixture of lactulose and Bacillus coagulans for 32 d before injection of saline or lipopolysaccharide (LPS). Piglets were sacrificed 4 h after LPS injection to collect samples to determine intestinal morphology, integrity and barrier functions as well as relative genes and proteins.

RESULTS

Our data showed that no differences were observed in the growth performance of the four test groups. LPS injection induced higher serum diamine oxidase activities, D-lactic acid levels, and endotoxin status, lower villus height and ratio of villus height to crypt depth, greater mRNA and lower protein expression related tight junction in both jejunum and ileum. In addition, a higher apoptosis index, and protein expression of Bax and caspase-3 were also observed in the LPS challenge group. Interestingly, dietary synbiotic mixture with lactulose and Bacillus coagulans protected against LPS-induced intestinal damage, barrier dysfunction and higher apoptosis as well as CTC.

CONCLUSIONS

Our data suggest that dietary supplementation of synbiotic mixture with lactulose and Bacillus coagulans showed resilience to LPS-induced intestinal morphological damage, barrier dysfunction and aggressive apoptosis in piglets as well as the protective effects of CTC. These results indicate that synbiotic mixture of lactulose and Bacillus coagulans showed beneficial effects on performance and resilience to acute immune stress in weaned piglets.

Dietary Supplementation with Puerarin Improves Intestinal Function in Piglets Challenged with Escherichia coli K88

The objective of this study was to investigate the effect of puerarin supplementation on the growth performance and intestinal function of piglets challenged with enterotoxigenic Escherichia coli (ETEC) K88. Twenty-four ternary crossbred piglets were randomly assigned to three treatment groups: control group, ETEC group (challenged with ETEC K88 on day 8), and ETEC + Puerarin group (supplemented with 5 mg/kg puerarin and challenged with ETEC K88 on day 8). All piglets were orally administered D-xylose (0.1 g/kg body weight) on day 10, and blood samples were collected after 1 h. Subsequently, piglets were killed and intestinal samples were collected for further analysis. The results showed that puerarin supplementation significantly decreased the adverse effects of ETEC K88-challenged piglets; significantly improved growth performance; increased the number of Bifidobacterium in the colon and Lactobacillus in the jejunum, cecum and colon; decreased the number of Escherichia coli in the jejunum and cecum; reduced the hydrogen peroxide content in the jejunum and myeloperoxidase activity in the jejunum and ileum; and increased the activities of catalase and superoxide dismutase in the jejunum and ileum. In addition, puerarin supplementation alleviated ETEC K88-induced intestinal injury in piglets, significantly downregulated the mRNA level of Interleukin-1β and upregulated the mRNA levels of intercellular cell adhesion molecule-1, myxovirus resistance protein 1, myxovirus resistance protein 2, and guanylate-binding protein-1 in the small intestine of piglets. In conclusion, dietary supplementation with puerarin could attenuate ETEC K88-induced intestinal injury by increasing the antioxidant and anti-inflammatory capacity and the number of beneficial intestinal bacteria in piglets.

Dietary Ulva lactuca and CAZyme supplementation improve serum biochemical profile and hepatic composition of weaned piglets

Ulva lactuca is a seaweed with antinutritional cell wall for monogastrics. Carbohydrate-Active enZymes (CAZymes) supplementation can potentially cause its disruption. This study evaluates four diets: Ctrl-control diet; UL-control + 7% U. lactuca (wild caught, powdered form); ULR-UL + 0.005% Rovabio^® Excel AP; ULU-UL + 0.01% ulvan lyase on piglets' haematologic and serologic profiles, hepatic lipids and minerals. White blood cells and lymphocytes reached the highest values in piglets fed UL compared to control, and to control and ULR; respectively (P < 0.05). IgG levels were boosted by seaweed incorporation compared to control (P = 0.015). The glycaemic homeostasis was assured by the seaweed inclusion. Dietary seaweed decreased serum lipids (P < 0.001), with the exception of ULU, due to HDL-cholesterol increase (P < 0.001). Cortisol was decreased in ULR and ULU (P < 0.001). No systemic inflammation was observed (P > 0.05). While hepatic n-3 PUFA increased in piglets fed with seaweed diets due to increment of beneficial 22:5n-3 and 22:6n-3 fatty acids (P < 0.05), the opposite occurred for n-6 PUFA, PUFA/SFA and n-6/n-3 ratios (P < 0.05). Hepatic pigments were unchanged (P > 0.05). ULR reduced α-tocopherol levels (P = 0.036) and increased serum potassium levels (P < 0.001) compared to control. Seaweed contributed to overcome piglets' weaning stress, with some benefits of including CAZyme supplementation.

Xylo-oligosaccharides improve the adverse effects of plant-based proteins on weaned piglet health by maintaining the intestinal barrier and inhibiting harmful bacterial growth

Introduction

Piglets are more susceptible to weaning stress syndrome when fed high levels of plant-based proteins that contain abundant food antigens and anti-nutritional factors. Xylo-oligosaccharides (XOS) are a potential prebiotic that may improve the tolerance of weaned piglets to plant-based proteins. The aim of this study was to investigate the effects of XOS supplementation in high and low plant-based protein diets on growth performance, gut morphology, short-chain fatty acid (SCFA) production, and gut microbiota of weaned piglets.

Methods

A total of 128 weanling piglets with an average body weight (BW) of 7.63 ± 0.45 kg were randomly allocated to one of the four dietary treatments in a 2 × 2 factorial arrangement, with two levels of plant-based proteins (d 1-14: 68.3 or 81.33%, d 15-28: 81.27 or 100%) and XOS complex (0 or 0.43%) over a 28-day trial.

Results

The growth performance of piglets did not differ significantly among groups (P > 0.05). However, the diarrhea index of weaned piglets fed a high plant-based protein diet (HP) was significantly higher than that of those fed a low plant-based protein diet (LP) at days 1-14 and throughout the experimental period (P < 0.05). XOS treatment tended to reduce the diarrhea index at days 1-14 (P = 0.062) and during the whole experiment period (P = 0.083). However, it significantly increased the digestibility of organic matter at days 15-28 (P < 0.05). Moreover, dietary XOS supplementation increased ileal mucosa mRNA expression of occludin and ZO-1 (P < 0.05). Furthermore, the concentration of butyric acid (BA) in the cecal contents and in the concentrations of BA and valeric acid (VA) in colon contents were significantly elevated in the XOS groups (P < 0.05). Additionally, XOS optimized the gut flora by lowering the number of pathogenic bacteria such as p_Campylobacterota, thereby stabilizing the gut ecosystem.

Discussion

In conclusion, the HP diet aggravated diarrhea in weaned piglets while the XOS diet alleviated it by improving nutrient digestibility, protecting intestinal morphology, and optimizing the gut flora.

Early feeding leads to molecular maturation of the gut mucosal immune system in suckling piglets

Introduction

Diet-microbiota-host interactions are increasingly studied to comprehend their implications in host metabolism and overall health. Keeping in mind the importance of early life programming in shaping intestinal mucosal development, the pre-weaning period can be utilised to understand these interactions in suckling piglets. The objective of this study was to investigate the consequences of early life feeding on the time-resolved mucosal transcriptional program as well as mucosal morphology.

Methods

A customised fibrous feed was provided to piglets (early-fed or EF group; 7 litters) from five days of age until weaning (29 days of age) in addition to sow's milk, whereas control piglets (CON; 6 litters) suckled mother's milk only. Rectal swabs, intestinal content, and mucosal tissues (jejunum, colon) were obtained pre- and post-weaning for microbiota analysis (16S amplicon sequencing) and host transcriptome analysis (RNA sequencing).

Results

Early feeding accelerated both microbiota colonisation as well as host transcriptome, towards a more "mature state", with a more pronounced response in colon compared to jejunum. Early feeding elicited the largest impact on the colon transcriptome just before weaning (compared to post-weaning time-points), exemplified by the modulation of genes involved in cholesterol and energy metabolism and immune response. The transcriptional impact of early feeding persisted during the first days post-weaning and was highlighted by a stronger mucosal response to the weaning stress, via pronounced activation of barrier repair reactions, which is a combination of immune activation, epithelial migration and "wound-repair" like processes, compared to the CON piglets.

Discussion

Our study demonstrates the potential of early life nutrition in neonatal piglets as a means to support their intestinal development during the suckling period, and to improve adaptation during the weaning transition.

Reducing Weaning Stress in Piglets by Pre-Weaning Socialization and Gradual Separation from the Sow: A Review

The weaning of pigs in most commercial pork production systems is an abrupt event performed at a fairly young age, i.e., mostly between 2.5 and 5 weeks of age. This practice induces a stress response, and its impact on behavior, performance and the gastrointestinal tract has been well described. Historically, there has been a focus on pre- and post-weaning nutritional strategies and post-weaning housing conditions and medication to improve production and reduce mortality after weaning. However, alternative pre-weaning housing and management systems that promote the development of natural social behaviors of piglets before weaning have recently received more attention. Co-mingling of non-littermates before weaning is a strategy that aims to initiate social interactions prior to weaning. The separation of the litter from the sow in the period leading up to weaning, termed intermittent suckling, aims to enhance the gradual separation from the sow. In addition, these practices encourage the young pig to learn explorative nutrient sourcing. Altogether, they may reduce weaning-associated stress. In this review, these strategies are defined, and their effects on behavior, performance, mortality, gastrointestinal function and immunocompetence are described. Though these strategies may be adapted to a commercial setting, it also becomes clear that many factors can contribute to the success of these strategies.