Effects of dietary combinations of organic acids and medium chain fatty acids as a replacement of zinc oxide on growth, digestibility and immunity of weaned pigs

A blend of medium-chain fatty acids, butyrate, organic acids, and a phenolic compound accelerates microbial maturation in newly weaned piglets

Inclusion of additive blends is a common dietary strategy to manage post-weaning diarrhea and performance in piglets. However, there is limited mechanistic data on how these additives improve outcomes during this period. To evaluate the effects of Presan FX (MCOA) on the intestinal microbiota and metabolome, diets with or without 0.2% MCOA were compared. Pigs fed MCOA showed improved whole-body metabolism 7 days post-weaning, with decreased (P < 0.05) creatine, creatinine and β-hydroxybutyrate. Alterations in bile-associated metabolites and cholic acid were also observed at the same time-point (P < 0.05), suggesting MCOA increased bile acid production and secretion. Increased cholic acid was accompanied by increased tryptophan metabolites including indole-3-propionic acid (IPA) in systemic circulation (P = 0.004). An accompanying tendency toward increased Lactobacillus sp. in the small intestine was observed (P = 0.05). Many lactobacilli have bile acid tolerance mechanisms and contribute to production of IPA, suggesting increased bile acid production resulted in increased abundance of lactobacilli capable of tryptophan fermentation. Tryptophan metabolism is associated with the mature pig microbiota and many tryptophan metabolites such as IPA are considered beneficial to gut barrier function. In conclusion, MCOA may help maintain tissue metabolism and aid in microbiota re-assembly through bile acid production and secretion.

The Effect of Dietary Supplementation with Zinc Amino Acids on Immunity, Antioxidant Capacity, and Gut Microbiota Composition in Calves

The aim of this study was to investigate the effect of dietary supplementation with zinc (Zn) amino acids at different concentrations on immunity, antioxidant capacity, and gut microbiota composition in calves. Twenty-four one-month-old healthy Angus calves of comparable body weight were randomly divided into three groups (four males and four females in each group) based on the amount of Zn supplementation added to the feed the animals received: group A, 40 mg/kg DM; group B, 80 mg/kg DM; and group C, 120 mg/kg DM. The experiment ended when calves reached three months of age (weaning period). The increase in dietary Zn amino acid content promoted the growth of calves, and the average daily weight gain increased by 36.58% (p < 0.05) in group C compared with group A. With the increase in the content of dietary Zn amino acids, the indexes of serum immune functions initially increased and then decreased; in particular, the content of immunoglobulin M in group A and group B was higher than that in group C (p < 0.05), whereas the content of interleukin-2 in group B was higher than that in the other two groups (p < 0.05). In addition, the content of superoxide dismutase and total antioxidant capacity in the serum of calves in group B was higher than that in group C (p < 0.05), and the MDA level was lower than in group C (p < 0.05). Moreover, alpha diversity in the gut microbiota of calves in group B was higher than that in group A and group C (p < 0.05); the dominant phyla were Firmicutes and Bacteroidota, whereas the dominant genera were Unclassified-Lachnospiraceae and Ruminococcus. Linear discriminant analysis showed that the relative abundance of Bacteroides in the gut microbiota of calves in group B was higher than that in group A, and the relative abundance of Prevotellaceae-UCG-003 was higher compared to that in experimental group C. Thus, dietary supplementation of 80 mg/kg of Zn amino acids to calves could improve the immune function and antioxidant capacity, as well as enrich and regulate the equilibrium of gut microbiota, thus promoting the healthy growth of calves.

Effects of Different Combinations of Sodium Butyrate, Medium-Chain Fatty Acids and Omega-3 Polyunsaturated Fatty Acids on the Reproductive Performance of Sows and Biochemical Parameters, Oxidative Status and Intestinal Health of Their Offspring

The aim of the study was to investigate the comparative effects of different combinations of sodium butyrate (SB), medium-chain fatty acids (MCFAs), and omega-3 polyunsaturated fatty acids (n-3 PUFAs) on the reproductive performances of sows, as well as on the biochemical parameters, oxidative statuses, and intestinal health of the sucking piglets. A total of 30 sows were randomly allocated to five treatments: (1) control diet (CON); (2) CON with 1 g/kg of coated SB and 7.75 g/kg of coated MCFAs (SM); (3) CON with 1 g/kg of coated SB and 68.2 g/kg of coated n-3 PUFAs (SP); (4) CON with 7.75 g/kg of coated MCFAs and 68.2 g/kg of coated n-3 PUFAs (MP); (5) CON with 1 g/kg of coated SB, 7.75 g/kg of coated MCFAs and 68.2 g/kg of coated n-3 PUFA (SMP). The results showed that sows fed the SP, MP, and SMP diets had shorter weaning-to-estrus intervals than those fed the CON diet (p < 0.01). The piglets in the SM, SP, and MP groups showed higher increases in the plasma catalase and glutathione peroxidase activities than those of the CON group (p < 0.01). The diarrhea incidence of piglets in the SM, SP and SMP groups was lower than that of piglets in the CON group (p < 0.01). Additionally, the addition of SM, SP, MP, and SMP to the sow diets increased the contents of immunoglobulin A, immunoglobulin G, fat, and proteins in the colostrum (p < 0.01), as well as the plasma total superoxide dismutase activities (p < 0.01) in the suckling piglets, whereas it decreased the mRNA expressions of tumor necrosis factor-α, interleukin-1β, and toll-like receptor 4 in the jejunum mucosa of the piglets. The relative abundances of Prevotella, Coprococcus, and Blautia in the colonic digesta of the piglets were increased in the SM group (p < 0.05), and the relative abundances of Faecalibacterium increased in the SMP group (p < 0.05), compared with the CON group. The relative abundances of Collinsella, Blautia, and Bulleidia in the MP group were higher than those in the CON group (p < 0.05). Collectively, dietary combinations of fatty acids with different chain lengths have positive effects on the growth performances and intestinal health of suckling piglets.

Compound organic acid could improve the growth performance, immunity and antioxidant properties, and intestinal health by altering the microbiota profile of weaned piglets

This study aimed to investigate the impact of compound organic acid (COA) and chlortetracycline (CTC) on serum biochemical parameters, intestinal health, and growth performance of weaned piglets. Twenty-four piglets (24 d of age) were randomly allocated into three treatments with eight replicate pens (one piglet per pen). Feed the basal diet or a diet containing 3,000 mg/kg COA or 75 mg/kg CTC, respectively. Results showed that both COA and CTC significantly increased average daily gain and reduced diarrhea rates (P < 0.05). They also upregulated serum total antioxidant capacity and downregulated serum interleukin (IL-10) levels (P < 0.05), increased crude protein digestibility and propionic acid concentration in the colon, and decreased spermidine and putrescine contents (P < 0.05). Intestinal microbiota analysis revealed that both COA and CTC increased the Shannon and Chao1 index and decreased the relative abundance of Blautia and Roseburia, but increased the relative abundance of Clostridium-sensu-stricto-1. Correlation analysis indicated that Clostridium-sensu-stricto-1 may be closely related to inflammation levels and microbial metabolites in piglets. Based on the results, COA may be a potential substitute for CTC to reduce antibiotic use and biogenic amine emission while improving piglet growth and intestinal health.

Pilot study of the productivity and Salmonella seroprevalence in pigs administered organic acids

Control of Salmonella in pig/pork production is important to protect public health because pork is one of the main sources of human infection. Moreover, antimicrobial use in pig farms should be kept low to minimize development and transmission of antimicrobial resistance. This pilot study evaluated the productivity and Salmonella seroprevalence in pigs administered organic acids (OA) compared to pigs given growth promoters in one farm in Antioquia, Colombia. Two groups each consisting of 60 pigs of 6-weeks of age were studied for 4 months. One group was provided feed and water with OA (Selko pH^® and Selacid^®), whereas the other group (control) received antimicrobial growth promoters according to routine feeding practices (tylosin and zinc bacitracin). Blood samples were taken three times (T1-T3) and pigs were weighted five times to calculate daily weight gain (DWG) and feed conversion ratio (FCR). Initially when the pigs were 6 weeks old (T1), the Salmonella seroprevalence was 1.7% in both groups. When the pigs were 11 weeks old (T2), the seroprevalence was significantly lower in pigs provided OA compared to the control group (19 vs. 47%, P < 0.001), whereas when the pigs were 23 weeks old (T3), the seroprevalence did not differ between the groups (62 vs. 77%; P = 0.075). The cumulative DWG was significantly higher in the intervention group than in the control group (713 vs. 667 g/day; P < 0.001). The cumulative FCR did not differ between groups (2.80 vs. 2.77; P = 0.144). The pilot study indicates that cleaning the water pipes and administrating OA improve productivity in pigs and delay exposure to Salmonella spp. when compared with growth promoters. Thus, OA could replace antimicrobial growth promoters and reduce antimicrobial use and resistance. However, the study should be repeated before firmer conclusions can be drawn.

Performance of broiler chicken on dietary supplementation of protected organic acids blend

1. The fatty acid coated organic acids blend was evaluated for its potential as a growth promoter.2. A six-week experiment was conducted following a completely randomised design. One-day old broiler chicks (n=384) were randomly divided into four dietary groups (eight replicates per group). Diet treatments were an unsupplemented basal diet or containing 0.3, 0.6, and 1 g/kg of a coated organic acid blend. Birds were evaluated for growth performance, carcass traits, immune-competence, total viable count, and gut villus height.3. The broiler chickens fed with 1 g/kg organic acids blend showed significantly higher body weight gain with improved feed conversion ratio and lower mortality than those fed the basal diet.4. The carcass traits vis. eviscerated yield, dressing percentage, breast yield and relative weight of giblets, were significantly better in the group fed with 1 g/kg coated organic acids blend with reduction in abdominal fat.5. Significantly higher cell-mediated, humoral immune responses and villi height with higher lymphoid organ weight (bursa and thymus) and a significant decrease in the total viable count were recorded in birds fed 1 g/kg organic acids blend.6. The results indicated that dietary inclusion of coated organic acids blend (1 g/kg) improved growth performance, carcass traits, immunity, and gut health in broiler chicken and reduced total viable count and abdominal fat, indicating its potential role as a promising growth promoter in poultry.

Effects of medium chain triglycerides with organic acids on growth performance, fecal score, blood profiles, intestinal morphology, and nutrient digestibility in weaning pigs

Objective

This study was conducted to evaluate the effects of medium chain triglycerides (MCT) with organic acids (OA) on growth performance, fecal score, blood profiles, intestinal morphology, and nutrient digestibility in weaning pigs.

Methods

A total of 120 weaning pigs ([Yorkshire×Landrace]×Duroc) with an average body weight (BW) of 8.00±0.87 kg were assigned in five treatments considering sex and initial BW in 3 replications with 8 pigs per pen in a randomized complete block design. The experimental diets included a corn-soybean meal based basal diet with or without 0.1% or 0.2% MCT and 0.1% OA. The pigs were fed the diets for 5 weeks (phase 1, 0 to 2 weeks; phase 2, 3 to 5 weeks). A total of 15 barrows with an average BW of 12.48±0.37 kg were used to evaluate the nutrient digestibility by total collection method. The BW and feed intake were measured at the end of each phase. Blood samples and small intestine samples were collected at the end of each phase, too.

Results

Supplementing 0.1% MCT with 0.1% OA showed greater BW for week 5 and average daily gain (ADG) for overall period than control diet. Supplementing 0.1% MCT increased (p<0.05) ADG and improved (p<0.05) gain:feed ratio for phase 1. Dietary MCT and OA did not affect the fecal score and blood concentration of cortisol, immunoglobulin G, tumor necrosis factor-α, interleukin-1β (IL-1β), IL-6, and IL-10 in weaning pigs. Pigs fed the diets with 0.1% MCT had greater (p<0.05) villus height of duodenum and ileum for phase 1. Also, pigs fed the diet with 0.1% OA showed greater (p<0.05) villus height and villus height to crypt depth ratio of duodenum for phase 2. There was no significant difference in nutrient digestibility and nitrogen retention of pigs.

Conclusion

Addition of 0.1% MCT with 0.1% OA in weaning pig’s diet improved growth performance partly by enhancing intestinal morphology in weaning pigs.

Effect of dietary supplementation of lauric acid on growth performance, antioxidative capacity, intestinal development and gut microbiota on black sea bream (Acanthopagrus schlegelii)

A feeding trial of eight weeks was conducted to examine the influence of food supplementation with lauric acid (LA) on Acanthopagrus schlegelii (juvenile black sea bream). A 24 percent fish meal baseline diet was created, while the other two diets were generated with dietary supplementation of graded points of LA at 0.1 percent and 0.8 percent, respectively. Each diet was given a triplicate tank with 20 fish weighing 6.22 ± 0.19 g. In comparison with the control group, the weight gain rate, growth rate, as well as feed efficiency of fish fed of 0.1 percent diet of LA were considerably (P < 0.05) greater. The total body and dorsal muscle proximate compositions did not change significantly between groups (P > 0.05). Triglyceride (TG) content was considerably (P < 0.05) greater in the LA-supplemented meals eating group in comparison with the control group. In the group eating LA-supplemented meals, the height of villus and the number of goblet cells/villus were considerably (P < 0.05) larger. The microbial makeup of the gut was also studied. The differences in phyla, class, and family level were not statistically significant (P > 0.05). Firmicutes in the phylum, Betaproteobacteri, Gammaproteobacteria, and Clostridia in the class, and Clostridiaceae in the family were all substantially increased with higher levels of LA supplementation (P < 0.05). According to the findings of this study, an LA-supplemented diet improves fish development, antioxidative capability, gut microbiota and intestinal health.

Effects of zinc and Bacillus subtilis on the reproductive performance, egg quality, nutrient digestion, intestinal morphology, and serum antioxidant capacity of geese breeders

The effects of zinc (Zn) and Bacillus subtilis (B. subtilis) on reproductive performance, egg quality, nutrient digestion, intestine morphology, and antioxidant capacity were explored in geese breeders. Geese breeders (n = 120, 46-wk of age) were randomly assigned into 6 groups with 4 replicates of 5 birds each (1 male and 4 female). Breeders were fed diets with 2 levels of B. subtilis (2.5 × 10⁹ and 5 × 10⁹ CFU/kg) crossed with three levels of Zn (25, 45, and 65 mg/kg) for duration of 10-wk. The results showed that the egg laying rate (P < 0.05), fertility rate (P < 0.01), hatchability rate (P < 0.05), yolk color (P < 0.05), and the retentions of crude protein (P < 0.05), ether extract (P < 0.05) and phosphorus of geese breeders were improved by dietary supplementation of 5 × 10⁹ CFU/kg B. subtilis and 25 mg or 45 mg/kg Zn. The serum T-SOD (P < 0.05) was increased by 45 mg/kg Zn supplementation. The serum T-AOC (P < 0.05) and retention of Zn (P < 0.05) were increased by 5 × 10⁹ CFU/kg B. subtilis supplementation. The birds fed with 5 × 10⁹ CFU/kg B. subtilis and 25 mg or 45 mg/kg Zn showed improved villus length (P < 0.01) and villus length/ crypt depth (P < 0.01) in both the jejunum and ileum. In conclusion, the combination of B. subtilis and Zn may have synergistic effects on these parameters, and dietary inclusion of 5 × 10⁹ CFU/kg B. subtilis and 45 mg/kg Zn is recommended for improving the reproductive performance of geese breeders.

Sodium caprylate improves intestinal mucosal barrier function and antioxidant capacity by altering gut microbial metabolism

Short-chain fatty acids (SCFA) produced by gut microbial metabolism have been reported to regulate the immunological response and intestinal health of the host by activating G protein-coupled receptors (GPR). It is unclear whether medium-chain fatty acids (MCFA) improve the intestinal barrier function by activating GPR. This study was conducted to investigate the effects of sodium caprylate and sodium butyrate on antioxidant capacity and intestinal barrier function in IPEC-J2 treated with H₂O₂ and C57/BL6 mouse models. For in vitro and in vivo assays, mice and oxidation-damaged IPEC-J2 (NC) were treated with sodium caprylate (SC) and sodium butyrate (PC) to determine intestinal barrier and antioxidant functions of the host. In vitro, SC treatment increased the concentrations of glutathione and total antioxidant capacity, and expression of claudin-1 and claudin-3 in oxidation-damaged IPEC-J2 (P < 0.05). In vivo, SC treatment improved growth performance, intestinal morphology, expression of claudin-3, and activity of superoxide dismutase in mice (P < 0.05), but decreased interleukin-1β and interferon-γ concentrations in serum compared to the NC group (P < 0.05). Treatment with SC increased the populations of Prevotella_9 in the ileum and Lachnoclostridium and Roseburia in the colon, but decreased the abundances of Streptococcus and Enterococcus in the ileum and Lactobacillus and Clostridium_sensu_stricto_1 in the colon compared with the NC group (P < 0.05). Concentrations of SCFA increased in the SC and PC groups than in the NC group (P < 0.05). Ileal protein expression of GPR 43 in the SC and PC groups was significantly greater than that in the NC group (P < 0.05). In conclusion, our findings confirmed the important role of sodium caprylate in improving intestinal barrier function and gut health by activating GPR 43 through regulating gut microbial metabolism.

Maximum levels of cross-contamination for 24 antimicrobial active substances in non-target feed. Part 9: Polymyxins: colistin

The specific concentrations of colistin in non-target feed for food-producing animals, below which there would not be an effect on the emergence of, and/or selection for, resistance in bacteria relevant for human and animal health, as well as the specific antimicrobial concentrations in feed which have an effect in terms of growth promotion/increased yield were assessed by EFSA in collaboration with EMA. Details of the methodology used for this assessment, associated data gaps and uncertainties, are presented in a separate document. To address antimicrobial resistance, the Feed Antimicrobial Resistance Selection Concentration (FARSC) model developed specifically for the assessment was applied. However, due to the lack of data on the parameters required to calculate the FARSC, it was not possible to conclude the assessment until further experimental data become available. To address growth promotion, data from scientific publications obtained from an extensive literature review were used. Levels of colistin in feed that showed to have an effect on growth promotion/increased yield were reported. It was recommended to carry out studies to generate the data that are required to fill the gaps which prevented the calculation of the FARSC for these antimicrobials.

Effects of mulberry leaf silage on antioxidant and immunomodulatory activity and rumen bacterial community of lambs

Background

Rumen is a natural fermentation system and the microorganisms inside can effectively utilize plant bioresource and interact with host metabolism. Here, analysis of rumen microbiome, together with animal performance and serum metabolism in a lamb model were performed to identify the potential use of mulberry leaf silage (MS) to replace alfalfa silage (AS) as a new functional feed resource and to mining the novel specific mulberry leaf associated rumen bacteria interact with host metabolism.

Results

The lambs fed with MS diet showed improved antioxidant capacity and immune function compared to those fed AS diet. The MS diet significantly altered rumen microbiota α- and β-diversity and taxonomic composition. Microbial analysis revealed that Bifidobacterium, Lactobacillus and Schwartzia were enhanced, and Ruminococcaceae UCG-010 and Lachnospiraceae_XPB1014_group were down-regulated in the rumen of MS group. A strong association was also found between these rumen microbial taxa and host antioxidant and immunomodulatory capacity.

Conclusion

These findings indicated that mulberry leaf silage can be a high-quality feed source or bioactive pharmaceutical that is responsible for ruminant’s health benefits. The modified rumen microbial community by mulberry leaf silage were associated with the enhanced antioxidant capacity and immunomodulatory of lambs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-021-02311-1.

Sodium Decanoate Improves Intestinal Epithelial Barrier and Antioxidation via Activating G Protein-Coupled Receptor-43

The study was conducted to explore actions of decanoic acid on regulating intestinal barrier and antioxidant functions in intestinal epithelium cells isolated from porcine jejunum (IPEC-J2) and C57/BL6 mice models. In vitro and vivo assays, mice and IPEC-J2 cells treated by H₂O₂ were disposed of sodium decanoate and sodium butyrate to determine intestinal barrier and antioxidant functions of the host. Results showed that sodium decanoate upregulated expression of tight junction proteins and improved antioxidant capacity in both IPEC-J2 cells treated by H₂O₂ and mice models (p < 0.05). Sodium decanoate increased weight gain and ileal villus height of mice compared with control and sodium butyrate treatments (p < 0.05). Sodium decanoate increased α-diversity of ileal microbiota, volatile fatty acids concentration, and G protein-coupled receptor-43 (GPR-43) expression in the ileum and colon of mice (p < 0.05). In conclusion, sodium decanoate improved antioxidant capacity, intestinal morphology, and gut physical barrier of intestinal epithelial cells, resulting in an increase growth performance of mice, which is mediated through activating GPR-43 signaling.

Time for a Paradigm Shift in Animal Nutrition Metabolic Pathway: Dietary Inclusion of Organic Acids on the Production Parameters, Nutrient Digestibility, and Meat Quality Traits of Swine and Broilers

Because the application of antibiotic growth promoters (AGP) causes accelerated adverse effects on the animal diet, the scientific community has taken progressive steps to enhance sustainable animal productivity without using AGP in animal nutrition. Organic acids (OAs) are non-antibiotic feed additives and a promising feeding strategy in the swine and broiler industry. Mechanistically, OAs improve productivity through multiple and diverse pathways in: (a) reduction of pathogenic bacteria in the gastro-intestinal tract (GIT) by reducing the gut pH; (b) boosting the digestibility of nutrients by facilitating digestive enzyme secretion and increasing feed retention time in the gut system; and (c) having a positive impact and preventing meat quality deterioration without leaving any chemical residues. Recent studies have reported the effectiveness of using encapsulated OAs and synergistic mechanisms of OAs combinations in swine and broiler productivity. On the other hand, the synergistic mechanisms of OAs and the optimal combination of OAs in the animal diet are not completely understood, and further intensive scientific explorations are needed. Moreover, the ultimate production parameters are not similar owing to the type of OAs, concentration level, growth phase, health status of animals, hygienic standards, and environmental factors. Thus, those factors need to be considered before implementing OAs in feeding practices. In conclusion, the current review evaluates the basics of OAs, mode of action, novel strategies to enhance utilization, influence on growth performances, nutrient digestibility, and meat quality traits of swine and broilers and their potential concerns regarding utilization.

The effects and mechanisms of acids on the health of piglets and weaners – a review

The rearing of piglets is the most difficult period in the pigs’ production because of their poorly developed digestive system and the low activity of digestive enzymes. Problems in nutrition and stress cause some disorders in the functioning of the digestive system leading to diarrhea and the mortality of piglets. Starting in 2006 in the EU, a total ban on antibiotics in their use as growth promoters was introduced. Since then, new and safe feed additives have been sought in order to replace antibiotics. Organic and inorganic acids as well as their salts were recognized as effective and safe additives. Due to their properties, they can improve feed palatability and digestibility, reduce the buffer capacity of feed, impact the development and functioning of the pig’s digestive system and improve the health and growth parameters. However, the effectiveness of acids is related to their qualitative and quantitative share in the feed additive. In this review, some strategies for using organic acids, their mixtures and also some new multi-component products will be discussed.

Potential of blended organic acids to improve performance and health of broilers infected with necrotic enteritis

Organic acids (OA) and their blends have been shown to positively affect performance and health of broilers. However, the data in the literature are not consistent. This study examined the potential of blended short-chain fatty acids (SCFA) with medium-chain fatty acids (MCFA) as alternatives to antibiotic growth promoters (AGP) on performance, health and welfare of broilers infected with necrotic enteritis (NE). The additives used were: A) a blend of SCFA, MCFA, and a phenolic compound (SMP); B) a blend of free and buffered SCFA with MCFA (SMF); C) a blend of free and buffered SCFA with a high concentration of MCFA (SHM). A total of 1,404 Ross 308 one-day-old male parental chicks were randomly distributed into 78-floor pens with 13 replicates of 18 birds each. Six treatments were the following: T1, unchallenged control (UCC); T2, challenged control (CHC); T3, challenged group plus zinc bacitracin (BAC); T4, challenged group plus additive SMP; T5, challenged group plus additive SMF; T6, challenged group plus additive SHM. Challenged birds were gavaged with Eimeria spp. on d 9 and Clostridium perfringens EHE-NE18 on d 14. Post NE challenge and cumulatively, BWG, FCR, and nutrient digestibility of birds were compromised (P < 0.05) by NE challenge indicating a successful induction of sub-clinical NE. Additive SHM had higher BWG compared to CHC and BAC groups (P = 0.001; d 10 to 24) but not different from SMP and SMF groups (P > 0.05). All the 3 additive groups had lower FCR compared to CHC (P = 0.001; d 0 to 35), and exhibited similar jejunal lesions (d 16) compared to BAC and apparent ileal protein digestibility (d 21) compared to UCC and BAC groups (P > 0.05). Birds in additive SHM group had a higher concentration of serum IgA compared to all groups (P = 0.001) except additive SMF (P > 0.05; d 21). All the additive groups had lower footpad dermatitis and hock burns compared to CHC (P < 0.05). The findings suggest the potential of blended OA as alternatives to BAC to protect broilers from NE indicated by improved FCR, immunity, digestibility, and bird welfare.

Organic Acids Mixture as a Dietary Additive for Pigs-A Review

Simple Summary

Many countries have enforced a ban on the use of all antibiotics in animal feed as growth promoters due to public health concerns about the emergence of antimicrobial resistance. There are a variety of candidates for the replacement of antibiotic growth promoters like probiotic, prebiotics, herbs, or essential oil. Organic acids have been suggested as alternatives to replace antibiotics in the diets of animals. It is reported that the lower the pKa of the OAs, the greater its effect on the reduction of stomach pH and the lower its antimicrobial effect in the more distal portions during its transit through the GIT which eventually will have better effect on animal’s health as well as their performance. Herein, we focus on the use of organic acids’ mixture as feed additives in the diet of swine in term of their immune system, gut health, nutrient digestibility, and growth performance as well as gas emission.

Abstract

Due to the increasing safety concerns about the risk of spreading antibiotic resistance in the environment, and the presence of chemical residues in animal products, using organic acids (OAs) to replace antibiotic in the diet of farm animals has increased considerably in recent years. It has been suggested that OAs could attribute to diverse elements such as antimicrobial activity, decreasing the pH of digesta particularly in the gastrointestinal tract (GIT), slowing feed transit in the GIT to maximize feed digestion and nutrient absorption, inducing enzyme secretion and activity in the small intestine, and providing nutrients to intestinal tissue. It has been reported that OAs mixture might be more effective than individual OAs due to the synergistic effects of different pKa values and have a broad-spectrum activity. In conclusion, this review showed that an OA mixture, which can improve nutrient digestibility and growth performance, modulate intestinal bacterial populations and improve gut health, as well as decreasing gas emission, can be used as alternative to antibiotic growth promoters. However, the results of OA mixtures are not always consistent, and the response to dietary OAs could be affected by the type of OAs, dosage, feed formula, and the age of animals. In this review, we will give an overview of the current use of OAs mixture in swine feed.

Medium-chain fatty acids and monoglycerides as feed additives for pig production: towards gut health improvement and feed pathogen mitigation

Ongoing challenges in the swine industry, such as reduced access to antibiotics and virus outbreaks (e.g., porcine epidemic diarrhea virus, African swine fever virus), have prompted calls for innovative feed additives to support pig production. Medium-chain fatty acids (MCFAs) and monoglycerides have emerged as a potential option due to key molecular features and versatile functions, including inhibitory activity against viral and bacterial pathogens. In this review, we summarize recent studies examining the potential of MCFAs and monoglycerides as feed additives to improve pig gut health and to mitigate feed pathogens. The molecular properties and biological functions of MCFAs and monoglycerides are first introduced along with an overview of intervention needs at different stages of pig production. The latest progress in testing MCFAs and monoglycerides as feed additives in pig diets is then presented, and their effects on a wide range of production issues, such as growth performance, pathogenic infections, and gut health, are covered. The utilization of MCFAs and monoglycerides together with other feed additives such as organic acids and probiotics is also described, along with advances in molecular encapsulation and delivery strategies. Finally, we discuss how MCFAs and monoglycerides demonstrate potential for feed pathogen mitigation to curb disease transmission. Looking forward, we envision that MCFAs and monoglycerides may become an important class of feed additives in pig production for gut health improvement and feed pathogen mitigation.

Protected Organic Acids Improved Growth Performance, Nutrient Digestibility, and Decreased Gas Emission in Broilers

Simple Summary

Recently, the development of antimicrobial resistance of bacteria has become a global health problem. Such a situation has compelled nutritionists and researchers to explore other potential alternatives. Among a variety of candidates for the replacement of antibiotic growth promoters, organic acids (OAs), both individual and as a blend of several acids are the most promising ones as feed additives in animal production. Organic acids maintain cellular integrity of the gut lining and improve the digestive process by maintaining normal gut flora. Addition of OAs to the diet can improve the absorption rate of proteins, amino acids, and minerals. This may contribute not only in improving performance but also reducing nitrogen and phosphorus excretion. Besides, medium-chain fatty acids (MCFAs) constitute another type of acid and have been shown to be potential alternatives for in-feed antibiotics in farm animals as they have strong antibacterial activity against Gram-positive cocci and Escherichia coli. The combination of OAs and MCFAs has been reported to improve the nutrient digestibility, growth performance, proliferation of Lactobacillus, and immunity of the animal. The present study investigated the effect of a blend of dietary protected OAs and MCFAs on broiler chickens. The results of this study showed that the blend of OA and MCFA supplementation positively influenced growth performance, DM digestibility, excreta Lactobacillus counts, as well as NH₃ gas emission in broiler chickens.

Abstract

We investigated the effects of a blend of organic acids (OAs) and medium-chain fatty acids (MCFAs) supplementation in 800 1-d-old male Ross 308 broiler chickens (42 ± 0.90 g) in a 7-week study. Broiler chicks were randomly allocated into one of the five dietary treatments (16 birds per pen with 10 pens per treatment). Dietary treatments consisted of corn-soybean meal based basal diet and the basal diet supplemented with blend of OAs and MCFAs at 0.25, 0.5, 0.75 g, and 1 g per kg of feed. In the current study, during the whole experimental period, the inclusion of the blend of OAs and MCFAs in the basal diet linearly improved (p < 0.05) body weight gain (BWG), feed conversion ratio (FCR), and dry matter digestibility. The increasing inclusion of the blend of OA and MCFA levels in the diets linearly decreased (p = 0.002) feed intake during d 1 to 7. Broilers fed diets containing different levels of the blend of OAs and MCFAs showed a linear increase (p = 0.006) in Lactobacillus concentrations and decrease (p = 0.014) in ammonia (NH₃) at the end of the experiment. However, the blend of OAs and MCFAs did not affect carcass quality, E. coli, and Salmonella counts, as well as hydrogen sulfide and total mercaptans gas emission (p > 0.05). In conclusion, the blend of OA and MCFA supplementation positively influenced growth performance, DM digestibility, excreta Lactobacillus counts, as well as NH₃ gas emission in broiler chickens.

Impact of in-feed sodium butyrate or sodium heptanoate protected with medium-chain fatty acids on gut health in weaned piglets challenged with Escherichia coli F4. Arch Anim Nutr 2020;74:271-295. [PMID: 32108496 DOI: 10.1080/1745039x.2020.1726719]

Short and medium-chain fatty acids (SCFA and MCFA, respectively) are commonly used as feed additives in piglets to promote health and prevent post-weaning diarrhoea. Considering that the mechanism and site of action of these fatty acids can differ, a combined supplementation could result in a synergistic action. Considering this, it was aimed to assess the potential of two new in-feed additives based on butyrate or heptanoate, protected with sodium salts of MCFA from coconut distillates, against enterotoxigenic Escherichia coli (ETEC) F4⁺ using an experimental disease model. Two independent trials were performed in 48 early-weaned piglets fed a control diet (CTR) or a diet supplemented with MCFA-protected sodium butyrate (BUT+; Trial 1) or sodium heptanoate (HPT+; Trial 2). After 1 week of adaptation, piglets were challenged with a single oral inoculum of ETEC F4⁺ (minimum 1.4 · 10⁹ cfu). One animal per pen was euthanised on days 4 and 8 post-inoculation (PI) and the following variables assessed: growth performance, clinical signs, gut fermentation, intestinal morphology, inflammatory mediators, pathogen excretion and colon microbiota. None of the additives recovered growth performance or reduced diarrhoea when compared to the respective negative controls. However, both elicited different responses against ETEC F4⁺. The BUT+ additive did not lead to reduce E. coli F4 colonisation but enterobacterial counts and goblet cell numbers in the ileum were increased on day 8 PI and this followed higher serum TNF-α concentrations on day 4 PI. The Firmicutes:Bacteroidetes ratio was nevertheless increased. Findings in the HPT+ treatment trial included fewer animals featuring E. coli F4 in the colon and reduced Enterobacteriaceae (determined by 16S RNA sequencing) on day 4 PI. In addition, while goblet cell numbers were lower on day 8 PI, total SCFA levels were reduced in the colon. Results indicate the efficacy of MCFA-protected heptanoate against ETEC F4⁺ and emphasise the potential trophic effect of MCFA-protected butyrate on the intestinal epithelium likely reinforcing the gut barrier.

Evaluation of different blends of medium-chain fatty acids, lactic acid, and monolaurin on nursery pig growth performance. Transl Anim Sci 2020;4:txaa024. [PMID: 32705023 DOI: 10.1093/tas/txaa024]

A total of 710 pigs (Line 400 × 200, DNA, Columbus, net energy (NE)) were used in two experiments (Exp. 1: initially, 6.3 ± 0.05 kg; Exp. 2: initially, 6.8 ± 0.05 kg) to evaluate the effects of two medium-chain fatty acid (MCFA) based products on nursery pig growth performance. Following their arrival at the nursery facility, pigs were randomized to pens (five pigs per pen) and allowed a 4-d acclimation period. Thereafter, pens of pigs were blocked by initial weight and randomized to dietary treatment. In Exp. 1, the dietary treatments were a dose titration of: 0%, 0.5%, 1.0%, or 2.0% MCFA-based additive, as well as a diet including 1.0% MCFA from a 1:1:1 blend of C6:0, C8:0, and C10:0. In Exp.2, dietary treatments consisted of a basal diet containing no MCFA (control), the control diet with a 1.0% inclusion of four different blends of MCFA, lactic acid, and monolaurin or a diet with 1.0% added MCFA (a 1:1:1 blend of C6:0, C8:0, and C10:0). The four blends consisted of 50% C6:0, 20% lactic acid, and increasing levels of monolaurin (0%, 10%, 20%, and 30%) at the expense of C12:0 (30%, 20%, 10%, and 0%). Treatment diets were formulated and manufactured in two dietary phases. Data were analyzed as a randomized complete block design with pen as the experimental unit. In Exp. 1, overall (days 0-34), increasing CaptiSURE increased (linear, P ≤ 0.014) average daily gain (ADG) and average daily feed intake (ADFI). Feed efficiency improved (quadratic, P = 0.002) with increasing CaptiSURE up to 1.0% of the diet with no benefit thereafter. There was no evidence for differences between pigs fed 1.0% CaptiSURE and pigs fed the 1.0% MCFA blend of C6:0, C8:0, and C10:0. In Exp. 2, overall (days 0-35), pigs fed the 1.0% 1:1:1 MCFA blend had increased (P < 0.034) ADFI and ADG resulting in 0.9 kg greater final weight (P = 0.014) compared with the control group. There was no evidence that the mean performance of pigs fed the four blends of MCFA, lactic acid, and monolaurin were different from the pigs fed the control diet. In summary, the addition of a 1.0% 1:1:1 blend of C6:0, C8:0, and C10:0 in nursery pig diets improved ADG, ADFI, and gain to feed ratio (G:F) compared with pigs fed the control diet. In addition, providing nursery pigs with the MCFA product CaptiSURE, up to 2% of the diet, resulted in linear improvements in ADG and ADFI. Altering the C12:0 to monolaurin ratio and adding lactic acid did not improve growth performance compared with pigs fed the control diet.

Formation, nutritional value, and enhancement of characteristic components in black garlic: A review for maximizing the goodness to humans

Black garlic (BG) is essentially a processed food and obtained through the transformation of fresh garlic (FG) (Allium sativum L.) via a range of chemical reactions (including the Maillard reaction) and microbial fermentation. This review provides the up-to-date knowledge of the dynamic and complicated changes in major components during the conversion of FG to BG, including moisture, lipids, carbohydrates (such as sugars), proteins, organic acids, organic sulfur compounds, alkaloids, polyphenols, melanoidins, 5-hydroxymethylfurfural, vitamins, minerals, enzymes, and garlic endophytes. The obtained evidence confirms that BG has several advantages over FG in certain product attributes and biological properties (especially antioxidant activity), and the factors affecting the quality of BG include the type and characteristics of FG and processing technologies and methods (especially pretreatments, and processing temperature and humidity). The interactions among garlic components, and between garlic nutrients and microbes, as well as the interplay between pretreatment and main manufacturing process, all determine the sensory and nutritional qualities of BG. Before BG is marketed as a novel snack or functional food, more research is required to fill the knowledge gaps related to quantitative monitoring of the changes in metabolites (especially those taste-active and/or biological-active substances) during BG manufacturing to maximize BG's antioxidant, anticancer, antiobesity, anti-inflammatory, immunostimulatory, anti-allergic, hepatoprotective, cardioprotective and oxidative stress-/hangover syndrome-reducing functions, and beneficial effects on memory/nervous systems. Assessments of the quality, efficacy, and safety of BG should be performed considering the impacts of BG production conditions, postproduction handling, and intake methods.

Effects of Dietary Supplementation with Combination of Tributyrin and Essential Oil on Gut Health and Microbiota of Weaned Piglets

Simple Summary

The dietary inclusion of the combination of tributyrin with either oregano or methyl salicylate as a substitution to antibiotics improved intestinal morphological structure of weaned piglets and resulted in major changes in the profiles of intestine microbiota and metabolites, which exerted beneficial effects on intestinal health of piglets. Our study indicated that the combination of tributyrate with oregano or methyl salicylate could be used as an alternative feed additive to the antibiotics.

Abstract

The aim of this study was to determine the effects of dietary inclusion of the combination of tributyrin with oregano or methyl salicylate as a substitute to antibiotics on gut health and microbiota of piglets. A total of 48 weaned crossbred piglets (Duroc × Large White × Landrace, 8.79 ± 0.97 kg, 21 ± 1 d) were randomly allocated to four experimental groups and fed for 4 weeks: the basal diet (Con); the control plus antibiotics (AB); the control plus oregano and tributyrin (OT); and the control plus methyl salicylate and tributyrin (MT). Although a numerical improvement on feed intake, weight gain and feed conversion ratio was observed in the OT and MT as well as the AB group, the difference was not significant (p > 0.05). The OT and MT groups were larger in villus height in the duodenum compared to the Con (p < 0.05), and were larger in relative abundance of Firmicutes/Bacaeroides in the intestine compared to Con and AB groups (p < 0.01). The amount of major different metabolites was 6, 8 and 8 for the AB, OT and MT groups when compared to the Con, respectively. In conclusion, as a substitute for antibiotics the inclusion of the combination of tributyrin with either oregano or methyl salicylate to the diet of weaned piglets improved the intestinal morphological structure and altered intestinal microbiota and metabolites, which were beneficial to the animal health.

Role of acidifiers in livestock nutrition and health: A review

Ever since the European ban on use of in-feed antibiotics in food animals, the search for alternate antibiotic-free growth promoter is undertaken worldwide. There are few alternatives such as probiotics, pre-biotics, phytochemicals, enzymes and organic acids. Among these alternatives, the organic acids or simply acidifiers play an important role in gut health in animals. The acidifiers could be used to favourably manipulate the intestinal microbial populations and improve the immune response, hence perform an activity similar to antibiotics in food animals in countering pathogenic bacteria. Acidifiers also improve the digestibility of nutrients and increase the absorption of minerals. The incorporation of organic acids also leads to thinning of the intestinal lining which facilitates better absorption of nutrients and its efficient utilization. However, their effect will not be similar among all types of organic acids as their mechanism of activity is based on its pKa value. Moreover, there are claims about the neutralization of acids by the secretion of bicarbonates in the initial part of intestine, reactivity with metallic items in feed mills and reduced palatability due its bitter taste demands non-reactive and targeted delivery for better performance. Currently, coated salts of acidifiers are available commercially for use in food animals especially pigs and poultry. The present review highlights the role of different acidifiers in livestock nutrition with their potent applications in improving nutrient digestibility, mineral utilization, meat quality, enhancing immunity, antimicrobial effects in countering pathogenic bacteria, boosting performance and production, and thus safeguarding health of livestock animals and poultry.

Effects of Dietary Supplementation with Mulberry (Morus alba L.) Leaf Polysaccharides on Immune Parameters of Weanling Pigs

In this study, the effect of dietary supplementation of mulberry leaf polysaccharides (MLPs) on the immune parameters-i.e., the immune organ weight, serum immunoglobulins, cytokines, nitric oxide (NO) production, and insulin-Like growth factor-1 (IGF1) mRNA expression-of weanling pigs as a model animal was investigated. A total of 120 healthy weanling pigs (aged 28 ± 2 d) with the same body weights were randomly divided into four groups: (1) Control treatment (CT), basal diet (BD), (2) MLP low-dose treatment (MLT), 0.6 g/kg MLP + BD, (3) MLP high-dose treatment (MHT), 1.2 g/kg MLP + BD, and (4) antibiotic treatment (AT), 0.15 g/kg chlortetracycline + BD. The results revealed that the thymus and spleen indices were significantly increased (P < 0.05) in both MLT and MHT groups in comparison with the CT group, while the serum levels of immunoglobulin G (IgG), interleukin (IL)-1β, IL-2, IL-8, and interferon (IFN-γ) in the MLT group and IL-2, IL-6, and IFN-γ in the MHT group were also considerably greater (P < 0.05) than the corresponding levels in the CT group. The serum contents of IgG, IL-1β, IL-2, and IL-8 in the MLT group and IL-2 and IL-6 in the MHT group were significantly increased in comparison with the corresponding contents in the AT group (P < 0.05). The transformation rate of lymphocytes in the MLT and MHT groups was higher compared to the CT and AT groups. However, a notable difference was found between the MLT group and the two control groups. The peripheral lymphocyte NO production in the MLT, MHT, and AT groups was significant relative to the CT group. The expression levels of IGF1 mRNA in the liver and muscle longissimus tissues of both the MLT and MHT groups showed significant improvement (P < 0.05) over those in the CT group. Moreover, the IGF1 mRNA expression in the muscle longissimus from the MLT group was significantly higher than in the AT group. In conclusion, the results suggest that incorporating MLPs into the diets of weanling pigs improves the animals' metabolisms and immune functions, and the effects of the MLT group were superior to those of both the MHT and AT groups.

Efficacy of medium-chain fatty acid salts distilled from coconut oil against two enteric pathogen challenges in weanling piglets

BACKGROUND

The search for alternatives to antibiotics in pig production has increased the interest in natural resources with antimicrobial properties, such as medium-chain fatty acids (MCFA) as in-feed additives. This study evaluated the potential of a novel blend of MCFA salts (DIC) from distilled coconut oil with a lauric acid content to reduce enteropathogens and control intestinal diseases around weaning. Two experimental disease models were implemented in early-weaned piglets, consisting of two oral challenges: Salmonella Typhimurium (1.2 × 108 CFU) or enterotoxigenic Escherichia coli (ETEC) F4 (1.5 × 109 CFU). The parameters assessed were: animal performance, clinical signs, pathogen excretion, intestinal fermentation, immune-inflammatory response, and intestinal morphology.

RESULTS

The Salmonella challenge promoted an acute course of diarrhea, with most of the parameters responding to the challenge, whereas the ETEC F4 challenge promoted a mild clinical course. A consistent antipathogenic effect of DIC was observed in both trials in the hindgut, with reductions in Salmonella spp. plate counts in the cecum (P = 0.03) on d 8 post-inoculation (PI) (Salmonella trial), and of enterobacteria and total coliform counts in the ileum and colon (P < 0.10) on d 8 PI (ETEC F4 trial). When analyzing the entire colonic microbiota (16S rRNA gene sequencing), this additive tended (P = 0.13) to reduce the Firmicutes/Bacteroidetes ratio and enriched Fibrobacteres after the Salmonella challenge. In the ETEC F4 challenge, DIC prompted structural changes in the ecosystem with increases in Dialister, and a trend (P = 0.14) to increase the Veillonellaceae family. Other parameters such as the intestinal fermentation products or serum pro-inflammatory mediators were not modified by DIC supplementation, nor were the histological parameters. Only the intraepithelial lymphocyte (IEL) counts were lowered by DIC in animals challenged with Salmonella (P = 0.07). With ETEC F4, the IEL counts were higher with DIC on d 8 PI (P = 0.08).

CONCLUSIONS

This study confirms the potential activity of this MCFA salts mixture to reduce intestinal colonization by opportunistic pathogens such as Salmonella or E. coli and its ability to modulate colonic microbiota. These changes could explain to some extent the local immune cell response at the ileal level.

Comparative effects of dietary supplementations with sodium butyrate, medium-chain fatty acids, and n-3 polyunsaturated fatty acids in late pregnancy and lactation on the reproductive performance of sows and growth performance of suckling piglets

This study was conducted to compare the effects of adding sodium butyrate (SB), medium-chain fatty acids (MCFAs), or n-3 polyunsaturated fatty acids (n-3 PUFAs) to the diet of sows during late gestation and lactation on the reproductive performance of sows and the growth performance and intestinal health of suckling piglets. Twenty-four sows (Landrace × Large-White hybrid; third parity; 200 ± 15 kg) were randomly assigned to receive 1 of 4 diets: basal diet (control group), basal diet + 1 g SB/kg (SB group), basal diet + 7.75 g MCFA/kg (MCFA group), or basal diet + 68.2 g n-3 PUFA/kg (n-3 PUFA group). The experiment began on day 85 of gestation and ended day 22 of lactation. Colostrum samples were collected from each sow. After the experiment, blood and tissue samples were collected from 1 randomly selected piglet. The results showed that the weaning-to-estrus interval of sows in the SB, MCFA, and n-3 PUFA groups was shorter than that of sows in the control group (P < 0.05). The incidence of diarrhea in suckling piglets in the SB, MCFA, and n-3 PUFA groups was lower than that of piglets in the control group (P < 0.05). The fat, protein, IgA, IgG, and IgM concentration in colostrum from sows increased following dietary supplementation with SB, MCFA, or n-3 PUFA (P < 0.05). Comparison with the control group, the mRNA expression of claudin-1, zona occludens 1, and interleukin-10 increased in the jejunum mucosa of suckling piglets in the SB, MCFA, and n-3 PUFA groups, while that of TLR4 decreased (P < 0.05). Compared with the control group, the Chao1 and ACE indexes of microbial flora in the colon contents of piglets in the SB, MCFA, and MCFA groups increased (P < 0.05), while the relative abundance of Firmicutes, Actinobacteria, and Synergistetes decreased at the phylum level (P < 0.05). In conclusion, during late pregnancy and lactation, dietary SB supplementation had a greater effect on intestinal health and caused a greater decrease in preweaning mortality of suckling piglets than did dietary MCFA or n-3 PUFA supplementation; dietary MCFA supplementation shortened the weaning-to-estrus interval of sows to a greater extent than did dietary SB or n-3 PUFA supplementation; and dietary n-3 PUFA supplementation increased the fat and protein content in the colostrum to the greatest extent.

Multi-strain yeast fraction product supplementation can alleviate weaning stress and improve performance and health of piglets raised under low sanitary conditions

BACKGROUND

This study was conducted to evaluate the health benefits to weaning pigs, raised under low sanitary conditions, of dietary supplementation with a multi-strain yeast fraction product (Cyberlindnera jadinii and Saccharomyces cerevisiae). In total, 160 weaning pigs (7.21 ± 1.05 kg) were randomly allotted to two dietary treatments in a 6-week feeding trial. The dietary treatments included a corn-soybean meal-based basal diet (CON) and CON + 2 g kg^-1 multi-strain yeast fraction product (MsYF) during weeks 1-2 and 0.4 g kg^-1 MsYF during weeks 3-6.

RESULTS

The MsYF supplementation increased (P < 0.05) body weight (BW) at day 42 and average daily gain (ADG) during days 1-14 and days 1-42 (P < 0.05) compared to CON. The total tract digestibility of dry matter (DM), fecal Lactobacillus counts, and serum immunoglobulin G (IgG) concentration at day 42 were higher (P < 0.05) in pigs fed a MsYF supplemented diet. The concentration of serum haptoglobin in pigs receiving a MsYF-supplemented diet was higher (P < 0.05) at days 7, 14, and 42 than those receiving CON. The mRNA expression for INF-γ and TNF-α genes were lower (P < 0.05) at days 14 and 7 respectively and the expression of IL-6 and TLR-2 genes was lower (P < 0.01) at days 7 and 14 in pigs fed an MsFY supplemented diet than those fed CON.

CONCLUSION

Supplementation with a multi-strain yeast fraction product had a positive effect on ADG during the early post-weaning period and led to better health in weaning pigs. © 2019 Society of Chemical Industry.

Effect of chicken egg yolk immunoglobulins on serum biochemical profiles and intestinal bacterial populations in early-weaned piglets

This study was conducted to test the hypothesis that dietary supplementation with anti-E. coli, chicken egg yolk immunoglobulins (IgY), may affect early weaned piglet (EWP) intestinal functions and enteric micro-organisms. One hundred and forty-eight ([Landrace × Yorkshire] × Duroc) piglets, weaned at age day 21, were randomly assigned to receive one of three diets for 14 days. Treatment group one (control group) was fed the base diet. Treatment group two (antibiotics group) was fed the base diet which was supplemented with 100 ppm colistin sulphate and 15 ppm enramycin; treatment group three (IgY group) was fed the base diet which was supplemented with 500 mg/kg anti-E. coli IgY. The study evaluated the effects on EWPs of IgY on growth, serum biochemical, inflammatory profiles and also digestion content intestinal bacterial populations. Results showed no significant difference in diarrhoea rates between IgY-fed EWPs and antibiotic-treated EWPs. Serum biochemical analysis showed that EWPs fed an IgY-containing diet had both lower (p < 0.05) cholesterol and low-density lipoprotein compared to antibiotic-treated EWPs. Escherichia coli populations measured in IgY-fed EWP ileal contents, compared to the control group, were significantly reduced (p < 0.05). Enterococcus, Lactobacillus, Clostridium and Bifidobacterium populations were unaffected by the IgY treatment. Larger (p < 0.05) Enterococcus populations and lower (p < 0.05) expression levels of heat-stable enterotoxin b (STb) were observed in IgY-fed EWP caecal digesta compared to the control group. Enteric Lactobacillus significantly decreased (p < 0.05) in EWPs fed antibiotics while it was unaffected by IgY treatment. Dietary supplementation with anti-E. coli IgY has the potential to suppress enteric E. coli growth, but not Lactobacillus, Clostridium and Bifidobacterium. This promotes and maintains a healthy EWP intestinal environment. These findings suggest that IgY may be used as an alternative to antibiotics in EWP diets.

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

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

Evaluation of the blend of organic acids and medium-chain fatty acids in matrix coating as antibiotic growth promoter alternative on growth performance, nutrient digestibility, blood profiles, excreta microflora, and carcass quality in broilers

This study was conducted to evaluate the effects of the blend of organic acids (OAs) and medium-chain fatty acids (MCFAs) in broiler chickens. A total of 816 1-d-old male Ross 308 broiler chickens (35 ± 0.44 g) were randomly allocated into 1 of the following 6 dietary treatments (17 broilers per pen with 8 pens per treatment): dietary treatments consisted of corn-soybean meal-based basal diet and the basal diet supplemented with 0.02, 0.03, 0.04, 0.05, and 0.06% blend of OAs and MCFAs. The study lasted 5 wk during which growth performance was determined. In the current study, the inclusion of 0.02, 0.03, 0.04, 0.05, and 0.06% blend of OAs and MCFAs in the basal diet linearly increased (P < 0.05) body weight gain and improved feed conversion ratio (P < 0.0001) on day 7 to 14, day 14 to 35, as well as overall. Increasing inclusion of the blend of OAs and MCFAs levels in the diets also linearly increased (P = 0.001) the digestibility of dry matter on day 35. Broilers fed with different levels of the blend of OAs and MCFAs showed a linear increment (P = 0.042) in Lactobacillus concentration and decrease (P = 0.002) in Escherichia coli concentration. With regard to relative organ weight, a trend of linear reduction (P = 0.052) in bursa of Fabricius weight of broilers fed the blend of OAs and MCFAs was observed. There was a significant linear improvement (P = 0.011) in the IgG concentration associated with the inclusion of the blend of OAs and MCFAs levels in the diets. In conclusion, the blend of OAs and MCFAs supplementation positively influenced growth performance, nutrient digestibility, and excreta microflora in broiler chickens.

Effects of a blend of organic acids and medium-chain fatty acids with and without Enterococcus faecium on growth performance, nutrient digestibility, blood parameters, and meat quality in finishing pigs

An experiment was conducted to assess effects of Enterococcus faecium and a blend of organic acids (OAs) and medium-chain fatty acids (MCFAs) in finishing pigs. A total of 120 pigs [Duroc × (Yorkshire × Landrace); 51.04 ± 1.82 kg] were randomly assigned to five dietary treatments: CON, basal diet; BOM1, CON + 500 mg kg−1 blend of OAs and MCFAs; BOM2, CON + 1000 mg kg−1 blend of OAs and MCFAs; EBOM1, BOM1 + 20 mg kg−1 E. faecium; EBOM2, BOM2 + 20 mg kg−1 E. faecium. Pigs fed EBOM1 and EBOM2 diets had higher average daily gain and average daily feed intake (during days 36–70 and days 1–70) and greater digestibility of dry matter (days 35 and 70) compared with those fed BOM1 and BOM2 diets (P < 0.05). However, no differences on blood parameters and meat quality were observed between pigs offered BOM1 and BOM2 diets and those fed EBOM1 and EBOM2 diets (P > 0.05). In conclusion, supplementation with the combination of E. faecium and a blend of OAs and MCFAs was more effective in improving growth performance and nutrient digestibility than supplementation with blend of OAs and MCFAs alone in finishing pigs.

Effects of organic acid and medium chain fatty acid blends on the performance of sows and their piglets

This study was aimed to evaluate the effects of organic acid (OA) and medium-chain fatty acid (MCFA) blends on production performance of sows and their litters. A total of 36 sows (Landrace × Yorkshire, average parity is 3.3, SE = 0.2) were randomly allocated to three treatments with 12 replicates. Dietary treatments were as follows: CON, basal diet; MC1, CON + 0.1% OA, and MCFA blends; MC2, CON + 0.2% OA, and MCFA blends. During lactation, no differences were observed in body weight (BW) loss, average daily feed intake, backfat thickness, digestibility of dry matter, nitrogen, or energy of sows. There were linear increase (p < 0.05) in BW and average daily gain of sucking piglets. On parturition and weaning day, there was a linear increase (p < 0.05) in fecal Lactobacillus counts, as well as a linear decrease (p < 0.05) in fecal Escherichia coli counts of sows on weaning day. The sucking piglets also had a linear increase (p < 0.05) in fecal Lactobacillus counts and a linear decrease (p < 0.05) in fecal E. coli counts. In conclusion, dietary supplementation of OA and MCFA blends in sows exerts beneficial effects to sows shifted fecal microbiota by increasing Lactobacillus and decreased E. coli counts. It also improved the performance of piglets.

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

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

Blend of organic acids and medium chain fatty acids prevents the inflammatory response and intestinal barrier dysfunction in mice challenged with enterohemorrhagic Escherichia coli O157:H7

Impaired epithelial barrier function disrupts immune homeostasis and increases inflammation in intestines, leading to many intestinal diseases. The blend of organic acids (OAs) and medium chain fatty acids (MCFAs) has been shown to have synergistic bactericidal effect. In this study, we demonstrated that two blends of OAs and MCFAs (OM1 and OM2) could prevent the inflammatory response and intestinal barrier dysfunction in enterohemorrhagic Escherichia coli (EHEC)-infected mice. Treatments of OM1 and OM2 significantly reduced the body weight loss and production of IL-6 and TNF-α induced by EHEC. Mice treated with OM1 and OM2 showed decrease in serum D-lactic concentration, DAO activity and bacterial transfer to liver and spleen. Furthermore, OM1 and OM2 increased the expression of tight junction proteins occludin and ZO-1, mucus protein MUC-2, and host defense peptides mBD1, mBD2 and mBD3. Finally, OM1 and OM2 increased the population of Lactobacillus spp. and Bifidobacterium spp., but decreased that of E. coli in the cecum. These findings indicate that OM1 and OM2 may be used to develop a prophylactic agent for intestinal inflammation and injury in enteric pathogen infection.

Dietary supplementation with tributyrin prevented weaned pigs from growth retardation and lethal infection via modulation of inflammatory cytokines production, ileal expression, and intestinal acetate fermentation

Weanling pigs, with an underdeveloped intestine and immature immune system, are usually subjected to depressed feed intake, growth retardation, and postweaning diarrhea. The aim of this study was to determine 1) the growth response of weaned pigs to supplemental tributyrin (TB) and 2) the potential effects and mechanisms of TB in modulating immune responses of lipopolysaccharide (LPS)-challenged piglets. A total of 240 piglets (Duroc × Large White × Landrace) were weaned at 21 d of age to a control (basal diet), supplemented with antibiotics (AB; +AB), supplemented with TB (+TB), or with supplemental AB and TB (+AB+TB) diets, with 10 replicate pens (6 piglets/pen) per diet. At 49 d of age, male pigs from the control and +TB groups were intraperitoneally injected with LPS (25 μg/kg BW) or saline ( = 6) and sacrificed at 4 h after injection to collect blood, intestine, and digesta samples for biochemical analysis. There were higher ( < 0.05) feed intake and lower ( < 0.05) percentage of negative growth piglets in the +TB groups than in the control group during the first week after weaning. For piglets without LPS challenge, there were higher ( < 0.05) ileal fibroblast growth factor 19 () mRNA abundance and total bile acid concentrations in the +TB groups than in the control group, whereas downregulated ( < 0.05) expression was observed in the +TB groups after LPS challenge. Lipopolysaccharide challenge in the control group increased ( < 0.05) plasma tumor necrosis factor α and IL-6 concentrations and colonic amount and decreased ( < 0.05) colonic goblet cells and colonic and cecal acetate concentrations, with no differences ( > 0.05) observed between +TB groups following LPS challenge. Taken together, dietary supplementation with TB prevented growth retardation through stimulating the appetite of weaned pigs and protected piglets against lethal infection via modulation of inflammatory cytokines production, ileal expression, and intestinal acetate fermentation.

Novel marine polysaccharides and maternal nutrition to stimulate gut health and performance in post-weaned pigs

Post-weaning complications in piglets are characterised by a reduction in feed intake and growth, atrophy of small-intestine architecture, upregulation of intestinal inflammatory cytokines, alterations in gastrointestinal microflora, diarrhoea and heightened susceptibility to infection. Traditional measures to reduce weaning-associated intestinal dysfunction have centred on dietary inclusion of antibiotic growth promoters in weaning pig diets, or high concentrations of dietary minerals in the form of zinc oxide. However, these strategies are under scrutiny because of their role in promoting multi-drug resistant bacteria and the accumulation of minerals in the environment. Up to recently, the main focus on finding alternatives to in-feed antibiotic growth promoters has been on dietary manipulations post-weaning, through the use of feed additives in the post-weaning diet. However, there are also other strategies that could enhance the growth and health of the newly weaned pig. One of these strategies is the use of maternal nutrition to improve growth and health in her offspring. The development of the immune system begins in utero and is further developed after the colonisation of the gastrointestinal tract with microbiota during birth and post-natal life. The early establishment of this relationship is fundamental to the development and long-term maintenance of gut homeostasis. There are significant efforts being made to identify natural alternatives to support the development of the piglet gastrointestinal tract, in particular during the weaning period. Chemodiversity in nature, including microorganisms, terrestrial plants, seaweeds and marine organisms, offers a valuable source of novel bioactives. This review will discuss the development of the intestinal tract in the pig during gestation, lactation and post-weaning periods and the factors that influence intestinal health post-weaning. It will also discuss how feeding marine bioactives in both the maternal diet and the piglet diet can be used to alleviate the negative effects associated with weaning.

Colistin in Pig Production: Chemistry, Mechanism of Antibacterial Action, Microbial Resistance Emergence, and One Health Perspectives

Colistin (Polymyxin E) is one of the few cationic antimicrobial peptides commercialized in both human and veterinary medicine. For several years now, colistin has been considered the last line of defense against infections caused by multidrug-resistant Gram-negative such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Colistin has been extensively used orally since the 1960s in food animals and particularly in swine for the control of Enterobacteriaceae infections. However, with the recent discovery of plasmid-mediated colistin resistance encoded by the mcr-1 gene and the higher prevalence of samples harboring this gene in animal isolates compared to other origins, livestock has been singled out as the principal reservoir for colistin resistance amplification and spread. Co-localization of the mcr-1 gene and Extended-Spectrum-β-Lactamase genes on a unique plasmid has been also identified in many isolates from animal origin. The use of colistin in pigs as a growth promoter and for prophylaxis purposes should be banned, and the implantation of sustainable measures in pig farms for microbial infection prevention should be actively encouraged and financed. The scientific research should be encouraged in swine medicine to generate data helping to reduce the exacerbation of colistin resistance in pigs and in manure. The establishment of guidelines ensuring a judicious therapeutic use of colistin in pigs, in countries where this drug is approved, is of crucial importance. The implementation of a microbiological withdrawal period that could reduce the potential contamination of consumers with colistin resistant bacteria of porcine origin should be encouraged. Moreover, the management of colistin resistance at the human-pig-environment interface requires the urgent use of the One Health approach for effective control and prevention. This approach needs the collaborative effort of multiple disciplines and close cooperation between physicians, veterinarians, and other scientific health and environmental professionals. This review is an update on the chemistry of colistin, its applications and antibacterial mechanism of action, and on Enterobacteriaceae resistance to colistin in pigs. We also detail and discuss the One Health approach and propose guidelines for colistin resistance management.

Influence of medium-chain fatty acids and short-chain organic acids on jejunal morphology and intra-epithelial immune cells in weaned piglets

Medium-chain fatty acids (MCFA) and short-chain organic acids (SOA) are often used as feed additives in piglet diets. There are limited studies in pigs describing the impact of MCFA or SOA on gut morphology and the local immune system. The aim of this study was to investigate whether the supplementation of SOA (0.41% fumaric acid and 0.32% lactic acid), or the combination of SOA with MCFA (0.15% caprylic and capric acid) would have effects on gut morphology and intestinal immune cells in weaned piglets. A total number of 72 weaned piglets were randomly allocated into three experimental groups. Tissue samples of six animals per group were used to investigate the potential impact of the feed additives on villus length and crypt depth of the jejunum and to quantify intra-epithelial lymphocytes (IEL). CD3-positive IEL were determined via immunohistochemistry (IHC) and flow cytometry (FC), whereas CD2-, CD5-, CD8β-, CD16- and γδ TCR-positive IEL were only analysed by FC. The supplementation of MCFA and SOA did not significantly affect morphometric data. The FC data indicated that SOA significantly increased the quantity of CD2^- CD8^- γδ T cells in the jejunum epithelium. Both IHC and FC analyses of pig jejunum confirmed that the majority of IEL expressed the surface marker CD3 and could be classified as cytotoxic T lymphocytes. In conclusion, the data indicated that SOA increased the proportion of CD2^- CD8^- γδ T cells in the jejunal epithelium. Thus, SOA might enable a beneficial effect on the local immunity by increasing the constitutive number of potential effector cells to defeat infectious diseases.