Modulations of growth performance, gut microbiota, and inflammatory cytokines by trehalose on Salmonella Typhimurium-challenged broilers

Integrative Analysis of the Microbiome and Metabolome of Broiler Intestine: Insights into the Mechanisms of Probiotic Action as an Antibiotic Substitute

Antibiotic substitutes have become a research focus due to restrictions on antibiotic usage. Among the antibiotic substitutes on the market, probiotics have been extensively researched and used. However, the mechanism by which probiotics replace antibiotics remains unclear. In this study, we aimed to investigate this mechanism by comparing the effects of probiotics and antibiotics on broiler growth performance and intestinal microbiota composition. Results shown that both probiotics and antibiotics increased daily weight gain and reduced feed conversion rate in broilers. Analysis of ileum and cecum microorganisms via 16S rRNA gene sequencing revealed that both interventions decreased intestinal microbial diversity. Moreover, the abundance of Bacteroides increased in the mature ileum, while that of Erysipelatoclostridium decreased in the cecum in response to both probiotics and antibiotics. The main metabolites of probiotics and antibiotics in the intestine were found to be organic acids, amino acids, and sugars, which might play comparable roles in growth performance. Furthermore, disaccharides and trisaccharides may be essential components in the ileum that enable probiotics to replace antibiotics. These findings provide important insights into the mechanisms underlying the use of probiotics as antibiotic substitutes in broiler breeding.

Protective effects of sodium humate and its zinc and selenium chelate on the oxidative stress, inflammatory, and intestinal barrier damage of Salmonella Typhimurium-challenged broiler chickens

The objective of this study was to investigate the protective effects and mechanisms of dietary administration of sodium humate (HNa) and its zinc and selenium chelate (Zn/Se-HNa) in mitigating Salmonella Typhimurium (S. Typhi) induced intestinal injury in broiler chickens. Following the gavage of 109 CFU S. Typhi to 240 broilers from 21-d to 23-d aged, various growth performance parameters such as body weight (BW), average daily gain (ADG), average daily feed intake (ADFI), and feed ratio (FCR) were measured before and after infection. Intestinal morphology was assessed to determine the villus height, crypt depth, and chorionic cryptologic ratio. To evaluate intestinal barrier integrity, levels of serum diamine oxidase (DAO), D-lactic acid, tight junction proteins, and the related genes were measured in each group of broilers. An analysis was conducted on inflammatory-related cytokines, oxidase activity, and Nuclear Factor Kappa B (NF-κB) and Nuclear factor erythroid2-related factor 2 (Nrf2) pathway-related proteins and mRNA expression. The results revealed a significant decrease in BW, ADG, and FCR in S. typhi-infected broilers. HNa tended to increase FCR (P = 0.056) while the supplementation of Zn/Se-HNa significantly restored BW and ADG (P < 0.05). HNa and Zn/Se-HNa exhibit favorable and comparable effects in enhancing the levels of serum DAO, D-lactate, and mRNA and protein expression of jejunum and ileal tight junction. In comparison to HNa, Zn/Se-HNa demonstrates a greater reduction in S. Typhi shedding in feces, as well as superior efficacy in enhancing the intestinal morphology, increasing serum catalase (CAT) activity, inhibiting pro-inflammatory cytokines, and suppressing the activation of the NF-κB pathway. Collectively, Zn/Se-HNa was a more effective treatment than HNa to alleviate adverse impact of S. Typhi infection in broiler chickens.

Systematic review on microbiome-related nutritional interventions interfering with the colonization of foodborne pathogens in broiler gut to prevent contamination of poultry meat

This systematic review aimed to compile the available body of knowledge about microbiome-related nutritional interventions contributing to improve the chicken health and having an impact on the reduction of colonization by foodborne pathogens in the gut. Original research articles published between 2012 and 2022 were systematically searched in Scopus and PubMed. A total of 1,948 articles were retrieved and 140 fulfilled the inclusion criteria. Overall, 73 papers described 99 interventions against colonization by Escherichia coli and related organisms; 10 papers described 15 interventions against Campylobacter spp.; 36 papers described 54 interventions against Salmonella; 40 papers described 54 interventions against Clostridium perfringens. A total of 197 microbiome-related interventions were identified as effective against one or more of the listed pathogens and included probiotics (n = 80), prebiotics (n = 23), phytobiotics (n = 25), synbiotics (n = 12), organic acids (n = 12), enzymes (n = 4), essential oils (n = 14) and combination of these (n = 27). The identified interventions were mostly administered in the feed (173/197) or through oral gavage (11/197), in the drinking water (7/197), in ovo (2/197), intra amniotic (2/197), in fresh or reused litter (1/197) or both in the feed and water (1/197). The interventions enhanced the beneficial microbial communities in the broiler gut as Lactic acid bacteria, mostly Lactobacillus spp., or modulated multiple microbial populations. The mechanisms promoting the fighting against colonization by foodborne pathogens included competitive exclusion, production of short chain fatty acids, decrease of gut pH, restoration of the microbiome after dysbiosis events, promotion of a more stable microbial ecology, expression of genes improving the integrity of intestinal mucosa, enhancing of mucin production and improvement of host immune response. All the studies extracted from the literature described in vivo trials but performed on a limited number of animals under experimental settings. Moreover, they detailed the effect of the intervention on the chicken gut without details on further impact on poultry meat safety.

Trehalose Supplementation Effects on Growth, Intestinal Morphology, Gut Bacteria, and Footpad Dermatitis of Broiler Chickens Reared at High Density

This study aimed to measure the effects of trehalose (Tre) supplementation on the growth, intestinal morphology, gut bacteria, and footpad dermatitis (FPD) of broiler chickens reared at different stocking densities (SD). Four hundred newly hatched Ross 308 male chicks were randomly allocated to four groups of eight, following a 2 × 2 factorial arrangement in a randomized complete block design using two SDs (normal, 11; high, 14 birds/m2) and two diets: basal with and without 0.5% Tre. Tre supplementation was provided during the starter/grower phase, but not the finisher phase. Data were analyzed using a two-way analysis of variance. We observed no significant effects of SD or Tre, individually or combined, on body weight gain (BWG), feed intake (FI), and feed conversion ratio (FCR) during the starter/grower period. However, high SD decreased both BWG (P < 0.001) and FI (P < 0.05), and increased FCR (P < 0.001), during the finisher period. Whereas Tre reduced FCR (P < 0.05) as a main effect, no combined effect was observed on FCR. Over the total period, high SD negatively affected BWG and FCR (P < 0.001), and Tre significantly reduced FCR, with its effect unaffected by SD. No significant effects of SD or Tre were observed on jejunal morphology. The ileal abundance of Clostridium perfringens (P > 0.05) was not affected by high SD but was significantly reduced by Tre. Neither high SD nor Tre altered Lactobacillus spp. counts; however, high SD increased FPD lesion scores, whereas Tre had no effect. The study showed that Tre supplementation during the starter/grower period improved FCR during the finisher period, possibly by decreasing the abundance of C. perfringens in broiler chickens.

Determining the In Vivo Efficacy of Plant-Based and Probiotic-Based Antibiotic Alternatives against Mixed Infection with Salmonella enterica and Escherichia coli in Domestic Chickens

Restrictions on the use of antimicrobial compounds have led to a surge of interest in alternative solutions, such as natural, plant-based compounds. In our study, we investigated the efficacy of three feed supplements containing different additives, namely, probiotics (Lactobacillus spp., "Test substance A"), turmeric (Curcuma longa L., "Test substance B"), and fenugreek (Trigonella foenum graecum, "Test substance C"). In the experiment, we tested 180 birds of the Bábolna Tetra-SL laying hybrid breed that were infected with Salmonella enteritidis strains. The birds were randomly divided into six groups: three groups treated with the different additives, a negative control group, a positive control group, and an antibiotic-treated group using enrofloxacin. We examined the maturation and the time course of shedding of Salmonella; at the end of rearing, pathological and histopathological examinations were performed. When Salmonella was isolated from the cloacal swab samples, the enrofloxacin-treated group had a high number of animals shedding Salmonella by day 9, which was like the group treated with test material C. The greatest reduction in Salmonella shedding was observed in the groups treated with test materials A and B. In terms of pathological parameters, villus length and crypt depth were significantly better in the group treated with test material C compared to the positive and negative controls, and when comparing the body weight of the tested animals, the group treated with test material B had a significantly larger absorption surface area compared to the positive control group. Overall, the supplement with test material C proved to be the most effective. In the future, it is worthwhile to investigate the combination of the tested active substances for their possible synergistic effects and to perform a dose-response study to select the optimal dosage.

Salmonella Infection in Poultry: A Review on the Pathogen and Control Strategies

Salmonella is the leading cause of food-borne zoonotic disease worldwide. Non-typhoidal Salmonella serotypes are the primary etiological agents associated with salmonellosis in poultry. Contaminated poultry eggs and meat products are the major sources of human Salmonella infection. Horizontal and vertical transmission are the primary routes of infection in chickens. The principal virulence genes linked to Salmonella pathogenesis in poultry are located in Salmonella pathogenicity islands 1 and 2 (SPI-1 and SPI-2). Cell-mediated and humoral immune responses are involved in the defense against Salmonella invasion in poultry. Vaccination of chickens and supplementation of feed additives like prebiotics, probiotics, postbiotics, synbiotics, and bacteriophages are currently being used to mitigate the Salmonella load in poultry. Despite the existence of various control measures, there is still a need for a broad, safe, and well-defined strategy that can confer long-term protection from Salmonella in poultry flocks. This review examines the current knowledge on the etiology, transmission, cell wall structure, nomenclature, pathogenesis, immune response, and efficacy of preventative approaches to Salmonella.

Comparison of Lactiplantibacillus plantarum isolates from the gut of mice supplemented with different types of nutrients: a genomic and metabolomic study

Many studies have focused on the influence of dietary supplements on gut microbiota composition, but limited research have reported their effects on specific bacterial species in the gut. Lactiplantibacillus plantarum is one of the most widely studied probiotics, with a wide range of sources and good environmental adaptability. In this study, in order to elucidate the adaptation strategies of L. plantarum to the gut of mice supplemented with carbohydrates, peptides and minerals, whole genome resequencing and intracellular metabolites detection were performed, and high-frequency mutant genes and differential metabolites were screened. The results suggested different types of dietary supplements do have different effects on L. plantarum from the gut of mice. Additionally, KEGG annotation unveiled that the effects of these dietary supplements on the gene level of L. plantarum primarily pertained to environmental information processing, while the differential metabolites were predominantly associated with metabolism. This study provided new perspectives on the adaptive mechanism of L. plantarum in response to the host's gut environment, suggesting that the diversity of the genome and metabolome of L. plantarum was correlated with dietary supplements. Furthermore, this study offered useful guidance in the effective utilization of dietary supplements.

Salmonella spp. in poultry production-A review of the role of interventions along the production continuum

Salmonella is a significant pathogen of human and animal health and poultry are one of the most common sources linked with foodborne illness worldwide. Global production of poultry meat and products has increased significantly over the last decade or more as a result of consumer demand and the changing demographics of the world's population, where poultry meat forms a greater part of the diet. In addition, the relatively fast growth rate of birds which is significantly higher than other meat species also plays a role in how poultry production has intensified. In an effort to meet the greater demand for poultry meat and products, modern poultry production and processing practices have changed and practices to target control and reduction of foodborne pathogens such as Salmonella have been implemented. These strategies are implemented along the continuum from parent and grandparent flocks to breeders, the farm and finished broilers to transport and processing and finally from retail to the consumer. This review focuses on common practices, interventions and strategies that have potential impact for the control of Salmonella along the poultry production continuum from farm to plate.

Investigation of Trehalose Supplementation Impacting Campylobacter jejuni and Clostridium perfringens from Broiler Farming

In 2006, the European Commission banned the use of antibiotic promoters in animal feed. However, there is a new situation in poultry disease where it is necessary to study feed additives, which can overcome the diseases that were previously controlled through the addition of antibiotics and antimicrobial growth promoters in the feed. Therefore, trehalose was investigated to determine whether it impacts the growth performance and pathogenic bacteria (C. jejuni and C. perfringens) inoculation in broilers. In the first experiment, the tolerance of broilers to the addition of trehalose to their feed was investigated. There was no significant difference (p > 0.05) in body weight changes, daily weight gain, feed intake or feed conversion ratio during the feeding period. Within a 35-day feeding period, it was concluded that a trehalose dosage up to 10% does not exert a negative effect on broiler farming. Moreover, there was no significant difference (p > 0.05) in the broilers' growth performance, as well as C. jejuni and C. perfringens counts in the intestines and feces of broilers observed over a 5-week feeding period. However, Lactobacillus counts significantly increased in these groups with 3% and 5% trehalose supplementation. The findings indicate that trehalose supplementation in the feed cannot directly decrease C. jejuni and C. perfringens counts but may enhance gut health by raising Lactobacillus counts in chicken gut, particularly when enteropathogenic bacteria are present.

Tactics with Prebiotics for the Treatment of Metabolic Dysfunction-Associated Fatty Liver Disease via the Improvement of Mitophagy

Mitophagy/autophagy plays a protective role in various forms of liver damage, by renovating cellular metabolism linking to sustain liver homeostasis. A characterized pathway for mitophagy is the phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1)/Parkin-dependent signaling pathway. In particular, PINK1-mediated mitophagy could play an indispensable role in improving the metabolic dysfunction-associated fatty liver disease (MAFLD) which could precede to steatohepatitis (NASH), fibrosis, and hepatocellular carcinoma. In addition, the PI3K/AKT/mTOR pathway might regulate the various characteristics of cellular homeostasis including energy metabolism, cell proliferation, and/or cell protection. Therefore, targeting mitophagy with the alteration of PI3K/AKT/mTOR or PINK1/Parkin-dependent signaling to eliminate impaired mitochondria might be an attractive strategy for the treatment of MAFLD. In particular, the efficacy of prebiotics for the treatment of MAFLD has been suggested to be useful via the modulation of the PI3K/AKT/mTOR/AMPK pathway. Additionally, several edible phytochemicals could activate mitophagy for the improvement of mitochondrial damages, which could also be a promising option to treat MAFLD with providing liver protection. Here, the potential therapeutics with several phytochemicals has been discussed for the treatment of MAFLD. Tactics with a viewpoint of prospective probiotics might contribute to the development of therapeutic interventions.

Trehalose prevents glyphosate-induced testicular damage in roosters via its antioxidative properties

Glyphosate (GLY), an active ingredient of the most commonly used herbicide, when in crops and feed, is deleterious to male reproductive health. Trehalose (Tre), a naturally non-reducing disaccharide, is shown to counteract the adverse stresses due to its antioxidation effect. Thus, this study was designed to investigate whether Tre can improve GLY-induced testicular damage via suppressing oxidative stress. 60 healthy Hy-Line Brown breeder roosters were utilized to assess the protective effects of Tre supplementation against testicular oxidative damage caused by GLY. Data showed that Tre administration significantly alleviated GLY- induced reduction in testis weight, decreased GLY level in the testis tissues, and alleviated GLY-caused testicular pathological damage. Concurrently, GLY treatment significantly elevated serum malondialdehyde (MDA) and testicular reactive oxygen species (ROS) levels, decreased serum total anti-oxidation capacity (T-AOC), catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels, which were all notably reversed by Tre administration. Moreover, GLY- inhibited nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in rooster testis, a master regulator of oxidative stress, was markedly recovered by Tre administration. In summary, these findings demonstrated that Tre can prevent GLY-induced testicular damage in roosters by ameliorating oxidative stress.

Non-Antibiotics Strategies to Control Salmonella Infection in Poultry

Salmonella spp. is a facultative intracellular pathogen causing localized or systemic infections, involving economic and public health significance, and remains the leading pathogen of food safety concern worldwide, with poultry being the primary transmission vector. Antibiotics have been the main strategy for Salmonella control for many years, which has allowed producers to improve the growth and health of food-producing animals. However, the utilization of antibiotics has been reconsidered since bacterial pathogens have established and shared a variety of antibiotic resistance mechanisms that can quickly increase within microbial communities. The use of alternatives to antibiotics has been recommended and successfully applied in many countries, leading to the core aim of this review, focused on (1) describing the importance of Salmonella infection in poultry and the effects associated with the use of antibiotics for disease control; (2) discussing the use of feeding-based (prebiotics, probiotics, bacterial subproducts, phytobiotics) and non-feeding-based (bacteriophages, in ovo injection, vaccines) strategies in poultry production for Salmonella control; and (3) exploring the use of complementary strategies, highlighting those based on -omics tools, to assess the effects of using the available antibiotic-free alternatives and their role in lowering dependency on the existing antimicrobial substances to manage bacterial infections in poultry effectively.

Effect of trehalose supplementation in milk replacer on the incidence of diarrhea and fecal microbiota in preweaned calves

Trehalose, a nonreducing disaccharide consisting of d-glucose with α,α-1,1 linkage, was evaluated as a functional material to improve the gut environment in preweaned calves. In experiment 1, 173 calves were divided into two groups; the trehalose group was fed trehalose at 30 g/animal/d with milk replacer during the suckling period, and the control group was fed nonsupplemented milk replacer. Medication frequency was lower in the trehalose group (P < 0.05). In experiment 2, calves (n = 20) were divided into two groups (control group [n = 10] and trehalose group [n = 10]) based on their body weight and reared under the same feeding regimens as in experiment 1. Fresh feces were collected from individual animals at the beginning of the trial (average age 11 d), 3 wk after trehalose feeding (experimental day 22), and 1 d before weaning, and the fecal score was recorded daily. Fecal samples were analyzed for fermentation parameters and microbiota. The fecal score was significantly lower in the trehalose group than in the control group in the early stage (at an age of 14 to 18 d; P < 0.05) of the suckling period. Calves fed trehalose tended to have a higher proportion of fecal butyrate on day 22 than calves in the control group (P = 0.08). Population sizes of Clostridium spp. were significantly lower (P = 0.036), whereas those of Dialister spp. and Eubacterium spp. tended to be higher in the feces of calves in the trehalose group on day 22 (P = 0.060 and P = 0.083). These observations indicate that trehalose feeding modulated the gut environment and partially contributed to the reduction in medication frequency observed in experiment 1.