Recent Advances in Probiotic Application in Animal Health and Nutrition: A Review

Advances in research on the intestinal microbiota in the mechanism and prevention of colorectal cancer (Review)

The intestinal microbiota represents a diverse population that serves a key role in colorectal cancer (CRC) and its treatment outcomes. Advancements in sequencing have revealed notable shifts in microbial composition and diversity among individuals with CRC. Concurrently, animal models have elucidated the involvement of specific microbes such as Lactobacillus fragilis, Escherichia coli and Fusobacterium nucleatum in the progression of CRC. The present review aimed to highlight contributions of intestinal microbiota to the pathogenesis of CRC, the effects of traditional treatments on intestinal microbiota and the potential for microbiota modulation as a therapeutic strategy for CRC.

Beneficial effects of ε-polylysine on growth performance, antioxidant capacity, intestinal morphology, and gut microbiota in broilers fed a lysine-deficient diet

This study was conducted to investigate the effects of dietary ε-polylysine supplementation on growth performance, antioxidant capacity, intestinal morphology, and gut microbiota in broilers fed a lysine-deficient diet. A total of 960 one-day-old yellow-feathered broilers were randomly allocated into six groups with eight replicates and 20 birds per replicate. Birds in the six groups were fed a lysine-deficient basal diet (-0.20 % lysine, NC) or basal diets supplemented with 0.20 % L-lysine hydrochloride (normal lysine level, PC) or varying levels (0.10 %, 0.20 %, 0.30 %, or 0.40 %) of ε-polylysine hydrochloride for 10 weeks. Results showed that compared with the NC group, dietary supplementation with 0.10 % and 0.20 % of ε-polylysine improved growth performance, meat quality and intestinal morphology, evidenced by increased average daily gain, decreased feed-to-gain ratio, increased water holding capacity of breast muscle, and increased jejunal and ileal villus height in ε-polylysine-treated broilers (P < 0.05). In addition, 0.10 % and 0.20 % of ε-polylysine supplementation improved serum nitrogen metabolism, immune and antioxidant capacity to varying degrees. No significant diffrences in growth performance, meat quality, or intestinal morphology were observed among PC and ε-polylysine-supplemented groups (P > 0.05). Interestingly, compared with the PC group, dietary 0.10 % of ε-polylysine positively altered the microbiota composition of broilers, evidenced by the increased the relative abundance of beneficial bacteria (e.g., Faecalibacterium and Phascolarctobacterium) and decreased the abundance of harmful bacteria (e.g., Lachnoclostridium and Peptococcus). In conclusion, diets supplemented with ε-polylysine have beneficial effects on growth performance, meat quality, and gut health of broilers via replenishing lysine or favorably altering immune and antioxidant capacity and gut microbiota. The recommended supplemental amount of ε-polylysine in lysine-deficient diets (L-lysine content in the starter and growing diet is 0.95 % and 0.80 % of the basal diet, respectively) is 0.10 %-0.20 %.

Optimizing male layer chicken performance and health with probiotic supplementation: A sustainable alternative to antibiotic growth promoters

Background

The rising global concern over antibiotic resistance has heightened scrutiny of antibiotic growth promoters (AGPs) in poultry farming, prompting a shift toward alternative feed additives to ensure sustainable and safe poultry production. This trend aligns with the increasing demand for free-range and naturally raised chicken meat in various regions, including Indonesia. In response, Indonesian breeders have turned to medium-sized male layer chickens (MLCs) as substitutes for traditional free-range chickens. This practice, coupled with the need to replace AGPs, highlights the critical importance of exploring innovative and natural solutions to enhance poultry growth and health.

Aim

This study investigated the effects of probiotics as an alternative to AGPs on the growth performance, carcass traits, and immune organs of male ISA Brown layer chickens.

Methods

The 180-day-old male ISA Brown layer chickens were used for the study. The intervention included six treatments. T1 basal feed, T2 2.5 g AGP/kg feed, T3 1 ml probiotic/kg feed, T4 3 ml probiotic/kg feed, T5 4 ml probiotic/kg feed, and T6 5 ml probiotic/kg feed. Probiotics used were Lactobacillus acidophilus, Bifidobacterium sp., and Lactobacillus plantarum at a concentration of 1.2 × 109 CFU/ml. The feeding trial lasted for 21 days for chickens aged 21-42 days, assessing growth performance [body weight, feed consumption, digestibility, and feed conversion ratio (FCR)], carcass traits, non-edible organs, and immune organs.

Results

The findings demonstrate that probiotic supplementation significantly outperformed the AGP-treated group (T2) in enhancing growth performance, carcass weight, pectoral weight development, FCR, internal and immune organ weights, nutrient intake, and digestibility. While AGPs showed improvements over the control (T1), probiotic- supplemented groups, particularly T6, achieved superior results across all parameters, indicating that probiotics are not only a viable alternative to AGPs but also a more effective and sustainable approach for poultry production.

Conclusion

The probiotics used in the study at 4 and 5 ml/kg of feed significantly enhanced the performance, immune organ development, and carcass attributes of MLCs, demonstrating their effectiveness as a viable alternative to AGPs. These findings highlight the potential of probiotics to improve poultry production sustainability by reducing reliance on antibiotics, enhancing growth and health outcomes, and promoting animal welfare through natural and efficient dietary interventions.

Microencapsulation and nanoencapsulation of bacterial probiotics: new frontiers in Alzheimer's disease treatment

Alzheimer's disease, a progressive neurodegenerative disorder marked by cognitive decline, affects millions worldwide. The presence of amyloid plaques and neurofibrillary tangles in the brain is the key pathological feature, leading to neuronal dysfunction and cell death. Current treatment options include pharmacological approaches such as cholinesterase inhibitors, as well as non-pharmacological strategies like cognitive training and lifestyle modifications. Recently, the potential role of probiotics, particularly strains, such as Lactobacillus and Bifidobacterium, in managing neurodegenerative diseases through the gut-brain axis has garnered significant attention. Probiotics can modulate inflammation, produce neurotransmitters, and support neuronal health, potentially slowing disease progression and alleviating symptoms, such as stress and anxiety. Optimizing the pharmacotherapeutic effects of probiotics is critical and involves advanced formulation techniques, such as microencapsulation and nanoencapsulation. Microencapsulation employs natural or synthetic polymers to protect probiotic cells, enhancing their viability and stability against environmental stressors. Methods like extrusion, emulsion, and spray-drying are used to create microcapsules suited for various applications. Nanoencapsulation, on the other hand, operates at the nanoscale, utilizing polymeric or lipid-based nanoparticles to improve the bioavailability and shelf life of probiotics. Techniques, such as nanoprecipitation and emulsification, are employed to ensure stable nanocapsule formation, thereby augmenting the therapeutic potential of probiotics as nutraceutical agents. This study delves into the essential formulation aspects of microencapsulation and nanoencapsulation for beneficial probiotic strains, aimed at managing Alzheimer's disease by optimizing the gut-brain axis. The insights gained from these advanced techniques promise to enhance probiotic delivery efficacy, potentially leading to improved health outcomes for patients suffering from neurodegenerative disorders.

A review of emerging technologies, nutritional practices, and management strategies to improve intramuscular fat composition in beef cattle

The flavour, tenderness and juiciness of the beef are all impacted by the composition of the intramuscular fat (IMF), which is a key determinant of beef quality. Thus, enhancing the IMF composition of beef cattle has become a major area of research. Consequently, the aim of this paper was to provide insight and synthesis into the emerging technologies, nutritional practices and management strategies to improve IMF composition in beef cattle. This review paper examined the current knowledge of management techniques and nutritional approaches relevant to cattle farming in the beef industry. It includes a thorough investigation of animal handling, weaning age, castration, breed selection, sex determination, environmental factors, grazing methods, slaughter weight and age. Additionally, it rigorously explored dietary energy levels and optimization of fatty acid profiles, as well as the use of feed additives and hormone implant techniques with their associated regulations. The paper also delved into emerging technologies that are shaping future beef production, such as genomic selection methods, genome editing techniques, epigenomic analyses, microbiome manipulation strategies, transcriptomic profiling approaches and metabolomics analyses. In conclusion, a holistic approach combining genomic, nutritional and management strategies is imperative for achieving targeted IMF content and ensuring high-quality beef production.

Lactococcus lactis MA5 is a potential autochthonous probiotic for nutrient digestibility enhancement and bacterial pathogen inhibition in hybrid catfish (Ictalurus punctatus × I. furcatus)

With the emergence of diseases, the U.S. catfish industry is under challenge. Current trends prefer autochthonous bacteria as potential probiotic candidates owing to their adaptability and capacity to effectively colonize the host's intestine, which can enhance production performance and bolster disease resistance. The objective of this study was to isolate an autochthonous bacterium as probiotic for hybrid catfish. Initially, an analysis of the intestinal microbiota of hybrid catfish reared in earthen ponds was conducted for subsequent probiotic development. Twenty lactic acid bacteria were isolated from the digesta of overperforming catfish, and most of the candidates demonstrated probiotic traits, including proteolytic and lipolytic abilities; antagonistic inhibition of catfish enteric bacterial pathogens, negative haemolytic activity and antibiotic susceptibility. Subsequent to this screening process, an isolate of Lactococcus lactis (MA5) was deemed the most promising probiotic candidate. In silico analyses were conducted, and several potential probiotic functions were predicted, including essential amino acids and vitamin synthesis. Moreover, genes for three bacteriocins, lactococcin A, enterolysin A and sactipeptide BmbF, were identified. Lastly, various protectant media for lyophilization of MA5 were assessed. These findings suggest that Lactococcus lactis MA5 can be an autochthonous probiotic from hybrid catfish, holding promise to be further tested in feeding trials.

Sustainable agriculture: leveraging microorganisms for a circular economy

Microorganisms serve as linchpins in agricultural systems. Classic examples include microbial composting for nutrient recovery, using microorganisms in biogas technology for agricultural waste utilization, and employing biofilters to reduce emissions from stables or improve water quality in aquaculture. This mini-review highlights the importance of microbiome analysis in understanding microbial diversity, dynamics, and functions, fostering innovations for a more sustainable agriculture. In this regard, customized microorganisms for soil improvement, replacements for harmful agrochemicals or antibiotics in animal husbandry, and (probiotic) additives in animal nutrition are already in or even beyond the testing phase for a large-scale conventional agriculture. Additionally, as climate change reduces arable land, new strategies based on closed-loop systems and controlled environment agriculture, emphasizing microbial techniques, are being developed for regional food production. These strategies aim to secure the future food supply and pave the way for a sustainable, resilient, and circular agricultural economy. KEY POINTS: • Microbial strategies facilitate the integration of multiple trophic levels, essential for cycling carbon, nitrogen, phosphorus, and micronutrients. • Exploring microorganisms in integrated biological systems is essential for developing practical agricultural solutions. • Technological progress makes sustainable closed-entity re-circulation systems possible, securing resilient future food production.

Multi-functional properties of lactic acid bacteria strains derived from canine feces

Introduction

Probiotics, especially Lactic Acid Bacteria (LAB), can promote the health of host animals in a variety of ways, such as regulating intestinal flora and stimulating the host's immune system.

Methods

In this study, 206 LAB strains were isolated from 48 canine fecal samples. Eleven LAB strains were selected based on growth performance, acid and bile salt resistance. The 11 candidates underwent comprehensive evaluation for probiotic properties, including antipathogenic activity, adhesion, safety, antioxidant capacity, and metabolites.

Results

The results of the antipathogenic activity tests showed that 11 LAB strains exhibited strong inhibitory effect and co-aggregation ability against four target pathogens (E. coli, Staphylococcus aureus, Salmonella braenderup, and Pseudomonas aeruginosa). The results of the adhesion test showed that the 11 LAB strains had high cell surface hydrophobicity, self-aggregation ability, biofilm-forming ability and adhesion ability to the Caco-2 cells. Among them, Lactobacillus acidophilus (L177) showed strong activity in various adhesion experiments. Safety tests showed that 11 LAB strains are sensitive to most antibiotics, with L102, L171, and L177 having the highest sensitivity rate at 85.71%, and no hemolysis occurred in all strains. Antioxidant test results showed that all strains showed good H2O2 tolerance, high scavenging capacity for 1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) and hydroxyl (OH-). In addition, 11 LAB strains can produce high levels of metabolites including exopolysaccharide (EPS), γ-aminobutyric acid (GABA), and bile salt hydrolase (BSH).

Discussion

This study provides a thorough characterization of canine-derived LAB strains, highlighting their multifunctional potential as probiotics. The diverse capabilities of the strains make them promising candidates for canine dietary supplements, offering a holistic approach to canine health. Further research should validate their efficacy in vivo to ensure their practical application.

The Effect of a Direct Fed Microbial on Liveweight and Milk Production in Dairy Cattle

This longitudinal study aimed to quantify the effects of dietary supplementation of a direct-fed microbial (DFM) consisting of three lactobacilli isolates on milk yield, milk fat and protein yields, somatic cell count (SCC), and liveweight in a single dairy herd in Australia. A total of 150 dairy cows were randomly selected based on parity and days in milk and divided into two groups: control (n = 75) and DFM treatment (n = 75). Throughout the study, the two groups of cows were housed separately in a dry lot yard, and each group had their own feeding area. For the DFM treatment group, selected cows in mid-lactation were supplemented with 10 mL/cow/day of the DFM via top dressing of the feed for the remainder of the lactation and through the dry period, extending into subsequent lactation. The control group had no supplementation. The milk yield and liveweight were recorded daily. Milk samples were collected every two months for milk component analysis (fat, protein, and somatic cell count [SCC]). The DFM-treated cows gained more liveweight across the study (19.40 kg, 95% CI 0.44 kg; 38.30 kg, p = 0.05) compared to the control cows. In the second production year, the DFM-treated cows mobilized more liveweight (-6.06 kg, 95% CI -10.49 kg; -1.61 kg, p = 0.01) and produced more milk (0.39 L/d 95% CI 0.10; 0.89, p = 0.05). Over a full lactation, DFM cows yielded at least 258 L (95% CI 252 L; 265 L) more milk than controls. No significant differences were found in fat and protein yield or SCC. This study suggests that consistent and ongoing supplementation with a Lacticaseibacillus- and Lentilactobacillus-based DFM could have a positive effect on milk production, but further research is needed to understand the underlying mechanism.

The Impact of Essential Amino Acids on the Gut Microbiota of Broiler Chickens

The research involving the beneficial aspects of amino acids being added to poultry feed pertaining to performance, growth, feed intake, and feed conversion ratio is extensive. Yet currently the effects of amino acids on the gut microbiota aren't fully understood nor have there been many studies executed in poultry to explain the relationship between amino acids and the gut microbiota. The overall outcome of health has been linked to bird gut health due to the functionality of gastrointestinal tract (GIT) for digestion/absorption of nutrients as well as immune response. These essential functions of the GI are greatly driven by the resident microbiota which produce metabolites such as butyrate, propionate, and acetate, providing the microbiota a suitable and thrive driven environment. Feed, age, the use of feed additives and pathogenic infections are the main factors that have an effect on the microbial community within the GIT. Changes in these factors may have potential effects on the gut microbiota in the chicken intestine which in turn may have an influence on health essentially affecting growth, feed intake, and feed conversion ratio. This review will highlight limited research studies that investigated the possible role of amino acids in the gut microbiota composition of poultry.

Evaluation of different probiotics on growth, body composition, antioxidant capacity, and histoarchitecture of Mugil capito

We investigated the dietary effects of the single application of Saccharomyces cerevisiae, Lactobacillus bulgaricus, and their combination on growth, proximate composition of whole fish body, antioxidant defense, and histoarchitecture of hapa-reared Mugil capito. Healthy fish (Fish weighed = 10.30 ± 0.10 g at first) were randomly allocated into 4 equal groups, each with three replicates. These groups were designed as follows: (1) a group fed a basal diet without probiotics (control), (2) a group fed a diet containing S. cerevisiae (4 g/kg diet), (3) a group fed a diet containing L. bulgaricus (2 g/kg diet), and (4) the last group fed a diet containing a combination of both, all for a duration of 60 days. Probiotic-treated groups showed significantly better growth and nutrition utilization than the control group. Significant differences were observed in the crude fat and crude protein contents among the groups, with the combination group exhibiting the highest levels. However, there were no significant variations in ash content across all groups. The highest hepatic antioxidant capacity (superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) enzyme activities) was observed in the combination group. Thiobarbituric acid reactive substance (TBARS) concentrations were decreased significantly in all probiotic groups, suggesting improved oxidative stress resilience in these groups. The histomorphological analysis of the hepatopancreatic tissues revealed well-arranged parenchyma, increased glycogen storage, and melanomacrophage centers in probiotic-treated groups, particularly the combined probiotics group. Furthermore, the probiotic supplementation improved the histoarchitecture of the intestinal villi compared to the control group. To put it briefly, combined dietary administration of these probiotics improved growth, body composition, antioxidant defenses, and hepatic and intestinal health in hapa-reared M. capito, highlighting their promising role in promoting welfare and productivity.

Feeding laying hens with lactobacilli improves internal egg quality and animal health

Feeding animals with lactobacilli strains is a biotechnological strategy to improve production, food quality, and animal health. Thus, this study aimed to select new lactic acid bacteria (LAB) able to improve laying hens health and egg production. Forty Bovans White layers (two days old) were randomly divided into four experimental groups that receive an oral gavage with saline solution (control group) or with one of the three lactobacilli selected (KEG3, TBB10, and KMG127) by their antagonistic activity against the foodborne pathogen Bacillus cereus GGD_EGG01. 16 S rRNA sequencing identified KEG3 as Lentilactobacillus sp., and TBB10 and KMG127 as Lactiplantibacillus sp. The data showed that feeding birds with LAB increased weight uniformity and improved the internal quality of the eggs (high yolk index and Haugh unit) compared with the control group (p < 0.05). Beta-diversity analysis showed that LAB supplementation modifies the cecal microbiota of laying hens. The prokaryotic families Bacteroidaceae, Ruminococcaceae, Rikenellaceae, and Lactobacillaceae were most important to the total dissimilarity of the cecal microbial community (calculated by SIMPER test). At end of in vivo experiments, it was possible to conclude that the feed of laying hens with Lentilactobacillus sp. TBB10 and Lentilactobacillus sp. KEG3 can be an important biotechnological tool for improving food quality and animal health.

Emerging trends and applications in health-boosting microorganisms-specific strains for enhancing animal health

Recent advancements in specific strain of probiotics have shown promising trends and applications in both ruminant and non-ruminant animal health. This study emphasizes the importance of tailored probiotics for these animal categories, discussing their potential benefits in improving nutrient utilization, growth performance, and disease management. The study also explores the different routes of probiotics administration, highlighting the various methods of delivery. Specifically, it highlights the benefits of probiotics in ruminant production performance, including enhanced rumen health, growth rates, milk production, and reduced digestive disorders. Additionally, it discusses the advantages of probiotics in non-ruminant farming, such as improved feed conversion efficiency, nutrient absorption, growth rates, immune responses, and reduced gastrointestinal issues, leading to increased productivity and profitability. In conclusion, recent advancements in specific strain of probiotics offer promising prospects for improving animal health. Tailored probiotics have shown potential in enhancing growth, nutrient utilization, and disease prevention, contributing to sustainable and effective animal husbandry practices.

Effects of maggot antimicrobial peptides on growth performance, immune function, and cecal flora of yellow-feathered broilers

INTRODUCTION

This study investigated the effects of maggot antimicrobial peptides on growth performance, blood parameters, immune organ index, and cecum microbial diversity in yellow broilers.

METHODS

The addition of 100-300 mg/kg maggots antimicrobial peptides to the corn-soybean meal basal diet was evaluated. Two hundred and forty one-day-old yellow-feathered broilers were randomly divided into four groups (60 chickens in each group): basal diet group (BC group), basal diet group + 100, 200, 300 mg/kg maggots antimicrobial peptides (MDAL group, MDAM group, and MDAH group).

RESULTS

The result showed that the average daily feed intake (ADFI) of the BC group, MDAM group, and MDAH group was higher than that of the MDAL group (P > 0.05), the average daily gain of MDAM group and MDAH group was significantly higher than that of BC group and MDAL group (P < 0.05), but the feed-weight ratio (F/G) was significantly lower than that of BC group (P < 0.05). The total protein (TP) content in the MDAM group and MDAH group was significantly higher than that in the BC group (P < 0.05), and the albumin (ALB) content in the MDAH group was higher than that in the BC group (P > 0.05). The contents of IgA and IgG in the MDAH group were significantly higher than those in the BC group (P < 0.05). In contrast, the content of alanine aminotransferase (ALT) in the MDAH group was significantly lower than that in the BC group (P < 0.05). The thymus and spleen indexes of the MDAH group were significantly higher than those of the BC group (P < 0.05). 16S rDNA sequencing results showed that Bacteroidota and Bacteroides were the dominant phylum and genus of cecal microorganisms at the phylum and genus levels, respectively. Cecum microorganisms are mainly involved in biological processes such as energy production and conversion, amino acid transport and metabolism, and carbohydrate transport and metabolism.

DISCUSSION

It was concluded that adding different doses of maggot antimicrobial peptide to the basal diet could improve yellow-feathered broilers' growth and immune performance and change the cecum flora. The appropriate dose of antimicrobial peptide addition was 300 mg/kg.

Recent Advances in the Use of Probiotics to Improve Meat Quality of Small Ruminants: A Review

Meat from small ruminants is considered a high quality and delicacy product in many countries. Several benefits have been perceived from probiotics as dietary supplements, such as improved carcass weight, color, tenderness, flavor, muscle fiber structure, water-holding capacity, and healthy fatty acid profile of the meat. Thus, the present review focuses on the effect of probiotics on improving the quality of meat from small ruminants. Though many benefits have been associated with the use of probiotics, the findings of all the considered articles are not always consistent, and the mechanisms behind improving meat quality are not appropriately defined. This variability of findings could be due to the use of different probiotic strains, dosage rates, number of days of experiment, nutrition, breed, age, and health status of the animals. Therefore, future research should emphasize specific strains, optimal dose and days of administration, route, and mechanisms for the specific probiotic strains to host. This review provides a comprehensive overview of the use of probiotics for small ruminants and their impact on meat quality.

Featured Prebiotic Agent: The Roles and Mechanisms of Direct and Indirect Prebiotic Activities of Lactoferrin and Its Application in Disease Control

Lactoferrin (LF) is a glycoprotein found in mammalian milk, and lactoferricin is a peptide derived from LF hydrolysate. Both LF and lactoferricin (LFcin) have diverse functions that could benefit mammals. Bovine LF (BLF) and BLFcin exhibit a wide range of antimicrobial activities, but most probiotic strains are relatively resistant to their antibacterial effects. BLF and BLF hydrolysate can promote the growth of specific probiotics depending on the culture conditions, the dose of BLF or BLF-related peptides, and the probiotic strains used. BLF supplementation has been shown to modulate several central molecular pathways or genes in Lacticaseibacillus rhamnosus GG under cold conditions, which may explain the prebiotic roles of BLF. LF alone or in combination with selected probiotics can help control bacterial infections or metabolic disorders, both in animal studies and in human clinical trials. Various LF-expressing probiotics, including those expressing BLF, human LF, or porcine LF, have been developed to facilitate the combination of LFs with specific probiotics. Supplementation with LF-expressing probiotics has positive effects in animal studies. Interestingly, inactivated LF-expressing probiotics significantly improved diet-induced nonalcoholic fatty liver disease (NAFLD) in a mouse model. This review highlights the accumulated evidence supporting the use of LF in combination with selected LF-resistant probiotics or LF-expressing probiotics in the field.

Alternatives to antibiotics in veterinary medicine: considerations for the management of Johne's disease

Antibiotic resistance has become a major health concern globally, with current predictions expecting deaths related to resistant infections to surpass those of cancer by 2050. Major efforts are being undertaken to develop derivative and novel alternatives to current antibiotic therapies in human medicine. What appears to be lacking however, are similar efforts into researching the application of those alternatives, such as (bacterio)phage therapy, in veterinary contexts. Agriculture is still undoubtedly the most prominent consumer of antibiotics, with up to 70% of annual antibiotic usage attributed to this sector, despite policies to reduce their use in food animals. This not only increases the risk of resistant infections spreading from farm to community but also the risk that animals may acquire species-specific infections that subvert treatment. While these diseases may not directly affect human welfare, they greatly affect the profit margin of industries reliant on livestock due to the cost of treatments and (more frequently) the losses associated with animal death. This means actively combatting animal infection not only benefits animal welfare but also global economies. In particular, targeting recurring or chronic conditions associated with certain livestock has the potential to greatly reduce financial losses. This can be achieved by developing novel diagnostics to quickly identify ill animals alongside the design of novel therapies. To explore this concept further, this review employs Johne's disease, a chronic gastroenteritis condition that affects ruminants, as a case study to exemplify the benefits of rapid diagnostics and effective treatment of chronic disease, with particular regard to the diagnostic and therapeutic potential of phage.

Defined Pig Microbiota with a Potential Protective Effect against Infection with Salmonella Typhimurium

A balanced microbiota is a main prerequisite for the host's health. The aim of the present work was to develop defined pig microbiota (DPM) with the potential ability to protect piglets against infection with Salmonella Typhimurium, which causes enterocolitis. A total of 284 bacterial strains were isolated from the colon and fecal samples of wild and domestic pigs or piglets using selective and nonselective cultivation media. Isolates belonging to 47 species from 11 different genera were identified by MALDI-TOF mass spectrometry (MALDI-TOF MS). The bacterial strains for the DPM were selected for anti-Salmonella activity, ability to aggregate, adherence to epithelial cells, and to be bile and acid tolerant. The selected combination of 9 strains was identified by sequencing of the 16S rRNA gene as Bacillus sp., Bifidobacterium animalis subsp. lactis, B. porcinum, Clostridium sporogenes, Lactobacillus amylovorus, L. paracasei subsp. tolerans, Limosilactobacillus reuteri subsp. suis, and Limosilactobacillus reuteri (two strains) did not show mutual inhibition, and the mixture was stable under freezing for at least 6 months. Moreover, strains were classified as safe without pathogenic phenotype and resistance to antibiotics. Future experiments with Salmonella-infected piglets are needed to test the protective effect of the developed DPM.

Nanopore Sequencing Discloses Compositional Quality of Commercial Probiotic Feed Supplements

The market for the application of probiotics as a livestock health improvement supplement has increased in recent years. However, most of the available products are quality-controlled using low-resolution techniques and un-curated databases, resulting in misidentification and incorrect product labels. In this work, we deployed two workflows and compared results obtained by full-length 16S rRNA genes (16S) and metagenomic (Meta) data to investigate their reliability for the microbial composition of both liquid and solid forms of animal probiotic products using Oxford Nanopore long-read-only (without short-read). Our result revealed that 16S amplicon data permits to detect the bacterial microbiota even with the low abundance in the samples. Moreover, the 16S approach has the potential to provide species-level resolution for prokaryotes but not for assessing yeast communities. Whereas, Meta data has more power to recover of high-quality metagenome-assembled genomes that enables detailed exploration of both bacterial and yeast populations, as well as antimicrobial resistance genes, and functional genes in the population. Our findings clearly demonstrate that implementing these workflows with long-read-only monitoring could be applied to assessing the quality and safety of probiotic products for animals and evaluating the quality of probiotic products on the market. This would benefit the sustained growth of the livestock probiotic industry.

Effects of Clostridium butyricum on growth performance, meat quality, and intestinal health of broilers

This study investigated the effects of Clostridium butyricum on the growth performance, meat quality and intestinal health of broilers. A total of 800 one-day-old male Arbor Acres broilers were randomly assigned to two groups with 16 replicates of 25 broilers per group and fed with a basal diet (CON) or a basal diet supplemented with 1.5 × 10⁹ cfu/kg C. butyricum and 5 × 10⁸ cfu/kg C. butyricum at 1-21 d and 22-42 d, respectively (CB). The results indicated that C. butyricum significantly increased the final body weight, average daily gain at 1-42 d in the growth performance of broilers (P < 0.05). Moreover, C. butyricum significantly increased a 24 h * value and pH_24h value of breast meat but reduced the drip loss and shear force (P < 0.05). Regarding serum antioxidant indices, C. butyricum significantly increased the total superoxide dismutase (T-SOD) and total antioxidative capacity activities and reduced the malondialdehyde content (P < 0.05). Furthermore, the broilers in the CB demonstrated an increase in jejunal lipase and trypsin activities, villus height (VH) and VH-to-crypt depth ratio at 42 d compared with those in the CON (P < 0.05). C. butyricum also upregulated the intestinal mRNA levels of zonula occludens-1, nuclear factor erythroid 2-related factor 2 (Nrf2), SOD1 and interleukin-10 in the jejunal mucosa (P < 0.05), but it downregulated the mRNA levels of nuclear factor kappa B (NF-κB) and tumor necrosis factor-α (P < 0.05). These results indicate that C. butyricum can improve the growth performance and meat quality of broilers. In particular, C. butyricum can improve the intestinal health of broilers, which is likely to be related to the activation of the Nrf2 signaling pathway and inhibition of the NF-κB signaling pathway.

A Nanocomposite with Extracellular Vesicles from Lactobacillus paracasei as a Bioinspired Nanoantibiotic Targeting Staphylococcus aureus

The utilization of biomimetic materials that merge functional nanoparticles (NPs) with a cell-derived nanosized membrane is a state-of-the-art approach to harnessing cellular properties for biomedical applications. However, the development of biocompatible and species-selective biomimetic agents against hazardous pathogens threatening human health is still in its early stages. Herein, we report the synthesis and functional analysis of a novel nanoplatform in which a PEGylated MoS2-ZnO (MZ) nanocomposite was cloaked with a generally regarded as safe (GRAS)-grade Lactobacillus paracasei-derived extracellular vesicle (LPEV) for MZ-LPEV nanocomposite and evaluated its activity against Staphylococcus aureus. The MZ nanocomposite was characterized via X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy. The coating of MZ with LPEV was confirmed through nanoparticle tracking analysis and zeta potential measurements. MZ-LPEV exhibited 5- to 20-fold higher antibacterial activity than that of ZO NPs and MZ nanocomposite against S. aureus. Reactive oxygen species (ROS) production and bacterial membrane disruption were confirmed as antibacterial mechanisms of MZ-LPEV. Finally, MZ-LPEV exhibited enhanced biocompatibility and selectivity for S. aureus. All our results showed that LPEV could be utilized for developing synergistic nanoantibiotics against S. aureus.

Full-Length 16S rRNA Gene Amplicon and Metagenome Taxonomic Profiling of Beneficial Microbes in Poultry and Swine Probiotic Product

Analysis of feed supplements can highlight microbial diversity and the prevalence of antimicrobial resistance (AMR), allowing users to monitor the safety of their animals. The 16S amplicon and metagenomic data generated by nanopore sequencing revealed that Bacillus was the dominant prokaryote, and AMR genes were detected in the animal probiotic products.

Occurrence and Risk Assessment of Fluoroquinolone Residues in Chicken and Pork in China

Antibiotics, especially fluoroquinolones, have been exhaustively used in animal husbandry. However, very limited information on the occurrence and exposure assessment of fluoroquinolone residues in chicken and pork in China is available to date. Thus, a total of 1754 chicken samples and 1712 pork samples were collected from 25 provinces in China and tested by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for residual determination of six common fluoroquinolones. The results revealed that the detection frequencies of fluoroquinolone residues were 3.99% and 1.69% in chicken and pork samples. The overall violation frequencies were 0.68% and 0.41% for chicken and pork. Enrofloxacin and its metabolite ciprofloxacin were found to be the most predominant fluoroquinolones. The occurrence of these antibiotics in different sampling regions and market types was analyzed. The %ADI values of enrofloxacin and ciprofloxacin were far less than 100, indicating the health risk associated with the exposure to these aforementioned fluoroquinolone residues via chicken and pork for Chinese children, adolescents, and adults was acceptable. The results provided useful references for Chinese consumers, and helped to appropriately use these antibiotics in poultry and livestock industry.