Effects of Lactobacillus reuteri and Streptomyces coelicolor on Growth Performance of Broiler Chickens

Microbiome analyses of poultry feeds: Part I. Comparison of five different DNA extraction methods

Given extensive variability in feed composition, the absence of a dedicated DNA extraction kit for poultry feed underscores the need for an optimized extraction technique for reliable downstream sequencing analyses. This study investigates the impact of five DNA extraction techniques: Qiagen QIAamp DNA Stool Mini Kit (Qiagen), modified Qiagen with Lysing Matrix B (MQ), modified Qiagen with celite purification (MQC), polyethylene glycol (PEG), and 1-Day Direct. Genomic DNA amplification and Illumina MiSeq sequencing were conducted. QIIME2-2021.4 facilitated data analysis, revealing significant diversity and compositional differences influenced by extraction methods. Qiagen exhibited lower evenness and richness compared to other methods. 1-Day Direct and PEG enhanced bacterial diversities by employing bead beating and lysozyme. Despite similar taxonomic resolution, the Qiagen kit provides a rapid, consistent method for assessing poultry feed microbiomes. Modified techniques (MQ and MQC) improve DNA purification, reducing bias in commercial poultry feed samples. PEG and 1-Day Direct methods were effective but may require standardization. Overall, this study underscores the importance of optimized extraction techniques in poultry feed analysis, with potential implications for future standardization of effective methods.

Comparative Genome Analysis and Characterization of the Probiotic Properties of Lactic Acid Bacteria Isolated from the Gastrointestinal Tract of Wild Boars in the Czech Republic

Probiotics are crucial components for maintaining a healthy gut microbiota in pigs, especially during the weaning period. Lactic acid bacteria (LAB) derived from the gastrointestinal tract of wild boars can serve as an abundant source of beneficial probiotic strains with suitable properties for use in pig husbandry. In this study, we analyzed and characterized 15 strains of Limosilactobacillus mucosae obtained from the gut contents of wild boars to assess their safety and suitability as probiotic candidates. The strains were compared using pan-genomic analysis with 49 L. mucosae strains obtained from the NCBI database. All isolated strains demonstrated their safety by showing an absence of transferrable antimicrobial resistance genes and hemolysin activity. Based on the presence of beneficial genes, five candidates with probiotic properties were selected and subjected to phenotypic profiling. These five selected isolates exhibited the ability to survive conditions mimicking passage through the host's digestive tract, such as low pH and the presence of bile salts. Furthermore, five selected strains demonstrated the presence of corresponding carbohydrate-active enzymes and the ability to utilize various carbohydrate substrates. These strains can enhance the digestibility of oligosaccharide or polysaccharide substrates found in food or feed, specifically resistant starch, α-galactosides, cellobiose, gentiobiose, and arabinoxylans. Based on the results obtained, the L. mucosae isolates tested in this study appear to be promising candidates for use as probiotics in pigs.

The Probiotic Potential and Metabolite Characterization of Bioprotective Bacillus and Streptomyces for Applications in Animal Production

Probiotics are increasingly recognized for their potential in managing bacterial challenges in animal production. This study aimed to evaluate the probiotic potential of Bacillus and Streptomyces strains, specifically their bioprotective ability against Salmonella. In agar inhibition assays, these bacteria supported Salmonella-inhibition zones, ranging from 2.5 ± 0.5 to 6.3 ± 2.0 mm. Analyses of antimicrobial metabolites revealed their capacity to produce compounds with anti-Salmonella properties, except for Bacillus subtilis MLB2. When Salmonella was exposed to lyophilized metabolites, inhibition occurred in both liquid (at concentrations between 250 and 500 g/L) and solid cultures (at 500 g/L). To confirm their probiotic potential, the S. griseus and Bacillus strains underwent evaluations for antimicrobial resistance, bile salt tolerance, auto- and co-aggregation, pH resistance, and their ability to adhere to and inhibit Salmonella in Caco-2 cells. These assessments confirmed their probiotic potential. The probiotic strains were further encapsulated and subjected to simulated swine and poultry digestion. They demonstrated survival potential through the gastrointestinal tract and significantly reduced the Salmonella population. Thus, these strains exhibit considerable promise for producing biotechnological products aimed at controlling Salmonella in animal production. This approach ensures the health and hygiene of farming facilities, mitigates the spread of zoonotic bacteria, and contributes positively to public health.

Gut microbiota reflect adaptation of cave-dwelling tadpoles to resource scarcity

Gut microbiota are significant to the host's nutrition and provide a flexible way for the host to adapt to extreme environments. However, whether gut microbiota help the host to colonize caves, a resource-limited environment, remains unknown. The nonobligate cave frog Oreolalax rhodostigmatus completes its metamorphosis within caves for 3-5 years before foraging outside. Their tadpoles are occasionally removed from the caves by floods and utilize outside resources, providing a contrast to the cave-dwelling population. For both cave and outside tadpoles, the development-related reduction in their growth rate and gut length during prometamorphosis coincided with a shift in their gut microbiota, which was characterized by decreased Lactobacillus and Cellulosilyticum and Proteocatella in the cave and outside individuals, respectively. The proportion of these three genera was significantly higher in the gut microbiota of cave-dwelling individuals compared with those outside. The cave-dwellers' gut microbiota harbored more abundant fibrolytic, glycolytic, and fermentative enzymes and yielded more short-chain fatty acids, potentially benefitting the host's nutrition. Experimentally depriving the animals of food resulted in gut atrophy for the individuals collected outside the cave, but not for those from inside the cave. Imitating food scarcity reproduced some major microbial features (e.g. abundant Proteocatella and fermentative genes) of the field-collected cave individuals, indicating an association between the cave-associated gut microbiota and resource scarcity. Overall, the gut microbiota may reflect the adaptation of O. rhodostigmatus tadpoles to resource-limited environments. This extends our understanding of the role of gut microbiota in the adaptation of animals to extreme environments.

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.

Probiotic Properties of Chicken-Derived Highly Adherent Lactic Acid Bacteria and Inhibition of Enteropathogenic Bacteria in Caco-2 Cells

Lactic acid bacteria (LAB) as probiotic candidates have various beneficial functions, such as regulating gut microbiota, inhibiting intestinal pathogens, and improving gut immunity. The colonization of the intestine is a prerequisite for probiotic function. Therefore, it is necessary to screen the highly adherent LAB. In this study, the cell surface properties, such as hydrophobicity, auto-aggregation, co-aggregation, and adhesion abilities of the six chicken-derived LAB to Caco-2 cells were investigated. All six strains showed different hydrophobicity (21.18-95.27%), auto-aggregation (13.61-30.17%), co-aggregation with Escherichia coli ATCC 25922 (10.23-36.23%), and Salmonella enterica subsp. enterica serovar Typhimurium ATCC 13311 (11.71-39.35%), and adhesion to Caco-2 cells (8.57-26.37%). Pediococcus pentosaceus 2-5 and Lactobacillus reuteri L-3 were identified as the strains with strong adhesion abilities (26.37% and 21.57%, respectively). Moreover, these strains could survive in a gastric acid environment at pH 2, 3, and 4 for 3 h and in a bile salt environment at 0.1%, 0.2%, and 0.3% (w/v) concentration for 6 h. Furthermore, the cell-free supernatant of P. pentosaceus 2-5 and L. reuteri L-3 inhibited the growth of enteropathogenic bacteria and the strains inhibited the adhesion of these pathogens to Caco-2 cells. In this study, these results suggested that P. pentosaceus 2-5 and L. reuteri L-3, isolated from chicken intestines might be good probiotic candidates to be used as feed additives or delivery vehicles of biologically active substances.

Characterization of a novel theta-type replicon of indigenous plasmid pTE15 from Lactobacillus reuteri N16

BACKGROUND

pTE15 is a ~ 15-kb narrow-host-range indigenous plasmid from Lactobacillus reuteri N16 that does not replicate in selected Bacillus spp., Staphylococcus spp., and other Lactobacillus spp.

METHODS

Combined deletion analysis the minireplicon essential of pTE15 with replicon-probe vector pUE80 (-) to confirmed sufficient for replication and from the ssDNA intermediate detection, plasmid amplification tested by chloramphenicol treatment, and replication origin sequence analysis to delineated the novel theta-type replication of pTE15.

RESULTS

Single-stranded intermediate of pTE15 DNA was not detected in L. reuteri, indicating that this plasmid does not replicate via a rolling circle mechanism. The replicon of pTE15 did not display the structural organization typical of rolling-circle plasmids, nor were they similar to known rolling-circle plasmids. We further provided evidence that this plasmid applied a new mode of theta-type replication mechanism: (1) the size of this plasmid was > 10-kb; (2) the minireplicon consisted of AT-rich (directed repeat, iteron) and DnaA sequences; (3) the minireplicon did not contain double-strand origin (DSO) and essential rep genes, and it also showed no single-strand origin (SSO) structure; (4) the intermediate single-stranded DNA products were not observed for pTE15 replication; (5) the minireplicon did not contain a typical essential replication protein, Rep, (6) its copy number was decreased by chloramphenicol treatment, and (7) genes in pTE15 replication region encoded truncated RepA (TRepA), RepB and RepC, which were replication-associated proteins, but they were not essential for pTE15 replication.

CONCLUSIONS

Collectively, our results strongly suggested that the indigenous plasmid pTE15 of L. reuteri N16 belongs to a new class of theta replicons.

Supplemental Enzyme and Probiotics on the Growth Performance and Nutrient Digestibility of Broilers Fed with a Newly Harvested Corn Diet

A new grain phenomenon happens in newly harvested corn because of its high content of anti-nutritional factors (ANFs), which can cause low nutrient digestibility and diarrhea in animals. Enzymes and probiotics have been shown to relieve the negative effect of ANFs for animals. The purpose of this study was to investigate the effect of enzymes and probiotics on the performance and nutrient digestibility of broilers, fed with newly harvested corn diets. A total of 624 Arbor Acres Plus male broiler chickens were randomly divided into eight treatment groups (A: normal corn diet, CT: newly harvested corn diet, DE: newly harvested corn diet + glucoamylase, PT: newly harvested corn diet + protease, XL: newly harvested corn diet + xylanase, BCC: newly harvested corn diet + Pediococcus acidilactici BCC-1, DE + PT: newly harvested corn diet + glucoamylase + protease, XL + BCC: newly harvested corn diet + xylanase + Pediococcus acidilactici BCC-1). Each group was divided into six replicates, with 13 birds each. On day 21, growth performance, nutrient digestibility, and digestive enzyme activity were measured. Compared with the normal corn diet (PC), the newly harvested corn diet (NC) produced shorter digesta emptying time (p = 0.015) and increased visual fecal water content (p = 0.002) of broilers, however, there was no effect on performance. Compared to the newly harvested corn diet (NC), supplemental enzyme of DE increased the activity of chymotrypsin (p = 0.016), however, no differences in the digestibility of three kinds of organic matter, digesta emptying time, visual fecal water content, or performance were found. Supplemental protease (PT) significantly increased digesta emptying time (p = 0.004) and decreased the activity of maltase (p = 0.007). However, it had no effect on the digestibility of three kinds of organic matter or the performance of broilers. Supplemental xylanase (XL) decreased the activity of amylase (p = 0.006) and maltase (p < 0.001); however, it had no effect on digesta emptying time, visual fecal water content, the digestibility of three kinds of organic matter, or performance of broilers. Supplemental DE, combined with PT (DE + PT), increased the digesta emptying time (p = 0.016) while decreasing the visual fecal water content (p = 0.011), and the activity of amylase (p = 0.011), lipase (p = 0.021), and maltase (p < 0.001), however, there was no effect on performance. Supplemental BCC individually decreased the activity of amylase (p = 0.024) and maltase (p < 0.001), however, it increased the activity of trypsin (p < 0.001) and tended to improve feed conversion ratio (FCR) (p = 0.081). Supplemental BCC-1, combined with XL (XL + BCC), increased the activity of trypsin (p = 0.001) but decreased the activity of amylase (p = 0.013), lipase (p = 0.019), and maltase (p < 0.001). Pediococcus acidilactici BCC-1 (109 cfu/kg), protease (800,000 U/g) individually, or protease (800,000 U/g) in combination with glucoamylase (800,000 U/g) were supplemented in newly harvested corn diets for growing broilers. Hence, this study mainly explores the alleviation effect of enzyme and probiotics on the negative phenomenon caused by the utilization of newly harvested corn in broilers and provides a better solution for the utilization of newly harvested corn in production practice.

Supplementation of multi-enzymes alone or combined with inactivated Lactobacillus benefits growth performance and gut microbiota in broilers fed wheat diets

The effects of multi-enzymes mixture supplementation or combination with inactivated Lactobacillus on growth performance, intestinal barrier, and cecal microbiota were investigated in broilers at the age of 15–42 days fed a wheat-based diet. A total of 576 broilers (12 broilers/cage; n = 12) were used and divided into four groups and randomly allotted to four experimental diets throughout grower (15–28 days of age) and finisher (29–42 days of age) phases. Diets consisted of a corn-soybean meal-based diet (BD), a wheat-soybean meal-based diet (WD), and WD supplemented multi-enzymes (WED) or combined with inactivated Lactobacillus (WEPD). The results showed that the average daily gain (ADG) and body weight (BW) were reduced in broilers fed WD diet compared with those fed BD diet during the grower period (P < 0.05). Broilers in the WED or WEPD group had higher ADG and BW during the grower period (P < 0.05) and had a lower feed-to-gain ratio (F/G) compared to broilers in the WD group during the grower and overall periods (P < 0.05). Improved expression of intestinal barrier genes (claudin-1, ZO-1, and mucin-2) was observed in WEPD compared to the BD or WD group (P < 0.05). Compared to the BD group, the WD group decreased the abundance of Oscillospira, norank_f__Erysipelotrichaceae, and Peptococcus, which are related to anti-inflammatory function and BW gain. The WD also increased Bifidobacterium and some short-chain fatty acid (SCFA)-producing bacteria (Anaerotruncus, Blautia, and Oscillibacter), and Barnesiella, which were presumed as “harmful microbes” [false discovery rate (FDR) < 0.05]. WED and WEPD groups, respectively, improved Bilophila and Eubacterium_hallii_group compared with those in the WD group (FDR < 0.05). In addition, the Enterococcus abundance was reduced in the WEPD group compared to the WD group (FDR < 0.05). Higher acetate and total SCFA concentrations were observed (P < 0.05) among broilers who received a WD diet. Compared with the WD group, the WED or WEPD group further increased cecal propionate content (P < 0.05) and tended to improve butyrate concentration. These results suggested that supplemental multi-enzymes alone and combined with inactivated Lactobacillus could improve the growth performance based on the wheat-based diet and offer additional protective effects on the intestinal barrier function of broilers.