Dietary sodium butyrate improves female broiler breeder performance and offspring immune function by enhancing maternal intestinal barrier and microbiota

Temporal changes in cecal luminal and mucosal microbiota of broiler chickens with clinical coccidiosis (Eimeria maxima)

Coccidiosis is a gastrointestinal disease caused by Eimeria parasites which leads to major economic losses in the poultry industry worldwide. Eimeria infection may alter the gut microbiota, which has been associated with chicken health and performance. This study aimed to determine the effects of Eimeria maxima infection on the luminal and mucosal microbiota of the cecum (CeL and CeM) at multiple time points post-infection (days 3, 5, 7, 10, and 14). Infection decreased Shannon diversity at d 3 (P = 0.03), increased observed features (ASVs) at d 5 (P < 0.01), and increased Shannon diversity at d 10 (P = 0.04) in the CeL microbiota compared to the control. In CeM microbiota, infection increased observed features at d 5 (P = 0.03), but later decreased observed features at d 14 (P = 0.01). Relative abundance of potential butyrate-producing bacteria such as [Ruminococcus] torques group in CeL and Butyricicoccus in CeM were decreased in infected birds, and some metabolic pathways related to butyrate production were predicted to be decreased. These findings show E. maxima may affect cecal microbiota alpha diversity in a time-dependent manner and reduce abundance of bacteria potentially important to gut health.

Gestational Inulin Supplementation in Low-/High-Fat Sow Diets: Effects on Growth Performance, Lipid Metabolism, and Meat Quality of Offspring Pigs

This study investigated whether the supplementation of prebiotic inulin to gestating sows programmatically affects offspring growth performance and meat quality while exploring its epigenetic effects through histone acetylation modulation. After mating, sixty multiparous sows (Landrace × Yorkshire; parity 2-3) were assigned to a 2 × 2 factorial arrangement with inulin (0% vs. 1.5%) and fat (0% or 5%) supplementation until farrowing. Post-weaning, five litters (10 piglets per litter) per treatment were selected and maintained in their original litter for fattening under standardized feeding. The results demonstrated that maternal inulin supplementation during gestation accomplished the following: (1) Increased offspring liver index by 13.4% at weaning and 6.8% at finishing (p < 0.05) while reducing the finishing-phase backfat thickness by 11.6% (p < 0.01), with a significant inulin × fat interaction attenuating fat-induced abdominal lipid accumulation at weaning (p = 0.05). (2) Decreased longissimus dorsi muscle lightness (L*) by 4.5% in finishing pigs (p = 0.02) without altering the other meat quality parameters. (3) Suppressed offspring liver lipid deposition at birth and finishing (p < 0.05), concomitant with upregulated hepatic PGC-1α and CPT1A expression (p < 0.05). (4) Elevated neonatal serum butyrate by 15.6% (p = 0.06) while inhibiting hepatic histone deacetylase (HDAC) activity and enhancing histone H3/H4 acetylation (p < 0.01). These findings suggest that maternal inulin supplementation during gestation mitigates offspring hepatic lipid deposition through butyrate-mediated epigenetic regulation, where microbial-derived butyrate from inulin fermentation inhibits HDAC activity, enhances histone acetylation levels, and upregulates fatty acid β-oxidation gene expression. This study provides novel mechanistic insights into how maternal dietary fiber nutrition programs offspring development through epigenetic reprogramming.

Selenium Broussonetia papyrifera polysaccharide alleviated cyclophosphamide-induced immune suppression, growth inhibition, intestinal damage, and gut microbiota disorder in yellow-feather broilers

This study aims to investigate the effects of selenium Broussonetia papyrifera polysaccharide (Se-BPP) on growth performance, immune regulation, intestinal barrier function, and gut microbiota in cyclophosphamide (CTX)-induced immunosuppressed chicks. A total of 120 one-day-old male yellow-feathered broilers were randomly divided into five groups: normal control group (NC), model control group (MC), low-dose Se-BPP group (Se-L), high-dose Se-BPP group (Se-H), and Astragalus polysaccharide (APS) group The Se-L and Se-H groups were supplemented with 0.1 % or 0.2 % Se-BPP, respectively, while the APS group was supplemented with 0.2 % APS. On days 22, 24, and 26, the NC group received intramuscular injections of 80 mg/kg saline, while the other groups received the same dose of CTX to induce immunosuppression in the chicks. The results showed that CTX caused growth retardation, immunosuppression, intestinal damage, and alterations in gut microbiota structure. Supplementation with Se-BPP improved average daily gain and reduced feed-to-gain ratio, promoting growth in immunosuppressed chicks. Se-BPP increased the immune organ index and serum content of IgG, IgM, IgA, SOD, GSH-Px, CAT, IL-2, IL-4, IL-6, IL-10, and INF-γ, thus alleviating the immunosuppression and oxidative stress caused by CTX. Additionally, Se-BPP enhanced the mRNA expression levels of ZO-1, Claudin 1, and MUC2 and increased villus height in the jejunum, effectively mitigating intestinal damage induced by CTX. Although the effect of Se-BPP on alpha diversity of the gut microbiota was not significant, it increased the abundance of beneficial bacteria such as Ruminococcus and Lactobacillus. In brief, this study demonstrated that adding Se-BPP to the diet could improve immunosuppression, intestinal damage, and microbiota disturbances in yellow-feather broiler chickens challenged with CTX, enhancing their production performance.

Growth Performance and Gut Health of Cold-Stressed Broilers in Response to Supplementation with a Combination of Sodium Butyrate and Vitamin D3

The current experiment aimed to investigate the effects of sodium butyrate (SB) and vitamin D3 (VD3) supplementation on the growth performance, immune status, antioxidant capacity, and gut health of young broilers under cold stress. A total of 144 1-day-old Arbor Acres chicks were randomly allotted to three treatments with 6 replicates of 8 birds: (1) basal diet; (2) basal diet + cold stress; and (3) basal diet with 1 g/kg SB and 2000 IU/kg VD3 + cold stress. Birds were exposed to cold stress at 16 ± 1 °C for 72 h (d 18-21) and 26 ± 1 °C for the control. The results indicated that the SB/VD3 diet could alleviate the reduction in average daily gain (ADG) caused by cold stress (p < 0.05). The SB/VD3 diet decreased the serum endotoxin level and ileal interleukin-1β gene expression and upregulated interleukin-10 and nuclear factor erythroid 2-related factor 2 (Nrf2) gene expression compared with cold-stressed birds (p < 0.05). Furthermore, cold stress altered the composition of gut microbiota, including a decrease in Clostridium_sensu_stricto_1, whereas the SB/VD3 diet prevented the reduction. In conclusion, the SB/VD3 diet mitigated the negative effects of cold stress on growth performance and the intestines by strengthening intestinal barrier function and stabilizing gut microbiota balance in broiler chicks, and these results can help to manage cold stress.

Methionine Supplementation of Maternal Diet Improves Hatching Traits, Initial Development, and Performance in Japanese Quail Fed Different Levels of Methionine During Growth

This study examined the effects of dietary levels of methionine on lipid and intestinal metabolism in Japanese quail hens and their progeny. The experiment was conducted according to a 3 × 3 factorial design, with three maternal and three progeny diets, as follows: low-methionine (LMET), recommended methionine (MET), and high-methionine (HMET). Methionine supplementation improved reproductive performance during laying (p < 0.05). Intestinal morphometry revealed that MET and HMET diets increased duodenal villus width and crypt depth in hens (p < 0.05). Hens fed the HMET diet showed higher expression of amino acid transport and barrier function genes. Hens fed LMET produced offspring with lower body weight at 15 days of age and lower weight gain (1-15 days of age) than hens fed MET and HMET (p = 0.0002). During the grower phase, chicks fed LMET diet had lower body weight at 15 (p < 0.0001) and 35 (p < 0.0001) days and worse feed conversion ratio (p = 0.0006) than chicks fed MET and HMET. Progeny from MET or HMET hens had improved intestinal histomorphometry. Overall, methionine supplementation of quail diets enhances intestinal function and reproductive performance in hens, improving chick performance in the starter and grower phases.

Effects of Interactions between Feeding Patterns and the Gut Microbiota on Pig Reproductive Performance

The feeding mode is an important factor affecting the reproductive performance of pigs. The composition and expression of the intestinal microbiota are closely related to the physiological and biochemical indicators of animals. Therefore, to explore the impact of different feeding patterns on the reproductive performance of pigs, this study collected reproductive performance data from 1607 Yorkshire pigs raised under different feeding patterns and conducted a fixed-effect variance analysis. Among them, 731 were in the artificial feeding (AM) group and 876 were in the feeding station feeding (SM) group. Additionally, 40 Yorkshire sows in the late gestation period were randomly selected from each feeding mode for intestinal microbiota analysis. The results of the analysis showed that, in the AM group, both the number of birth deformities (NBD) and the number of stillbirths (NSB) were significantly greater than they were in the SM group (p < 0.05). Additionally, the total number born (TNB) in the AM group was significantly lower than that in the SM group (p < 0.05). The results of the intestinal microbiota analysis revealed that at the phylum level, there were significant differences in nine bacterial taxa between the AM and SM groups (p < 0.05). At the genus level, the abundance of a variety of beneficial bacteria related to reproductive performance in the SM group was significantly greater than that in the AM group. Finally, fecal metabolomic analysis revealed that the contents of butyric acid, isovaleric acid, valeric acid, and isobutyric acid, which are associated with reproductive performance, in the feces of sows in the SM group were significantly higher than those in the AM group (p < 0.05). These results indicate that different feeding methods can affect the gut microbiota composition of Yorkshire pigs and further influence the reproductive performance of pigs through the gut microbiota-metabolic product pathway. The results of this study provide valuable insights for further exploring the relationships between feeding modes, intestinal microbial composition, and host phenotypes.

Feed additives and enrichment materials to reduce chicken stress, maximize productivity, and improve welfare

Environmental stress poses serious threats to animal welfare and production, particularly in poultry, which are susceptible to such stress. It can increase susceptibility to diseases and infections, reduce growth rates and reproductive performance, and increase behavioral issues. Environmental stress caused by conventional housing conditions can negatively affect well-being and productivity. High temperature, overcrowding, poor ventilation, insufficient lighting, and wire cages are some of the most prominent stressors in conventional housing systems. To address environmental stress in chicken farms, some strategies and tools, such as using anti-stress feed additives and enriching cages, can help improve bird behavioral activities and welfare. Breeders can improve overall bird performance by implementing these strategies and creating a more enriched and comfortable environment. Thus, this review discusses the importance of using different feed additives and environmental enrichment materials to reduce stress in chicken farms (broiler and layer) and improve bird productivity and well-being.

Dietary jack bean (Canavalia ensiformis L.) supplementation enhanced intestinal health by modulating intestinal integrity and immune responses of broiler chickens

This study investigated the influence of supplementing with jack beans on jejunal morphology, cecal short-chain fatty acids production, gene expression both of pro- and anti-inflammatory cytokines and tight junctions. Four treatment groups including 288 Indian River chicks that were one day old were randomized at random. While the treatment groups received jack bean supplementation at levels of 5 %, 10 %, and 15 %, the control group (0 %) was given a basal diet. For 11-35 days, each treatment consisted of 8 pens with 9 birds each. Supplementing with jack beans significantly enhanced butyrate production (P < 0.001), while at 10 % supplementation did not differ from control. Villus height (VH) and the ratio (VH:CD) were significantly (P < 0.001) increased by dietary treatments, while villus width (VW) and crypt depth (CD) were significantly (P < 0.05) decreased. TLR-3, TNF-a, and IL-6 were all significantly (P < 0.001) increased by dietary supplementation. However, at 15 %, TLR-3 and IL-6 were same with control. IL-18 was significantly (P < 0.05) decreased at 15 %. IL-10 decreased significantly (P < 0.001), but at 10 % same with control. At 5 and 10 %, IL-13 increased significantly (P < 0.001), whereas dietary treatments decreased at 15 % compared to control. Although ZO1 decreased significantly (P < 0.001) and OLCN increased significantly (P < 0.001), both ZO1 and OCLN were not significantly different from the control at 15 %. Dietary treatments significantly (P < 0.001) increased CLDN1 but did not differ from the control at 10 %. JAM2 decreased significantly (P < 0.001) with dietary treatments. In conclusion, jack bean supplementation may increase broiler chicken performance and intestinal health due to butyrate production. It may affect intestinal morphology and integrity by upregulating a tight junction protein gene. Jack beans also impacted jejunum immune responses and inflammatory cytokine gene expression.

Supplementation of coated sodium butyrate relieved weaning stress and reshaped microbial flora in weaned lambs

Weaning is an important period in the growth and development of lambs. Thus, effectively reducing the occurrence of weaning stress is critical for maintaining lamb production. Coated sodium butyrate has been shown to reduce inflammation, promote intestinal health, and maintain homeostasis. However, the application and potential mechanism of coated sodium butyrate in alleviating weaning stress in lambs are still unclear. To evaluate the effects of coated sodium butyrate on the growth performance, antioxidant capacity, and gut microbiota of weaned lambs, 10 weaned lambs of 21-day-old were randomly divided into two groups: the CON group (basal diet) and the NaB group (basal diet +3 g/kg of coated sodium butyrate). The trial lasted 21 days. The experimental results showed that compared to the CON group, coated sodium butyrate supplementation in the diet significantly increased the average daily weight gain and daily feed intake of lambs (p < 0.05). In addition, compared to the CON group, the addition of coated sodium butyrate also significantly decreased the serum MDA level of lambs (p < 0.05). Notably, the addition of coated sodium butyrate did not have a significant effect on the cecal microbiota, while increasing the diversity of colonic microbiota and promoting the abundance of Lachnospiraceae, Verrucomicrobiota, Akkermansia, Roseburia, and Sinobacteraceae, which are associated with the nutrient absorption of lambs (p < 0.05). These results indicate that dietary supplementation with coated sodium butyrate could promote the growth and antioxidant capacity of weaned lambs and alleviate weaning stress.

Effects of Eimeria acervulina infection on the luminal and mucosal microbiota of the cecum and ileum in broiler chickens

Coccidiosis, an intestinal disease caused by Eimeria parasites, is responsible for major losses in the poultry industry by impacting chicken health. The gut microbiota is associated with health factors, such as nutrient exchange and immune system modulation, requiring understanding on the effects of Eimeria infection on the gut microbiota. This study aimed to determine the effects of Eimeria acervulina infection on the luminal and mucosal microbiota of the cecum (CeL and CeM) and ileum (IlL and IlM) at multiple time points (days 3, 5, 7, 10, and 14) post-infection. E. acervulina infection decreased evenness in CeL microbiota at day 10, increased richness in CeM microbiota at day 3 before decreasing richness at day 14, and decreased richness in IlL microbiota from day 3 to 10. CeL, CeM, and IlL microbiota differed between infected and control birds based on beta diversity at varying time points. Infection reduced relative abundance of bacterial taxa and some predicted metabolic pathways known for short-chain fatty acid production in CeL, CeM, and IlL microbiota, but further understanding of metabolic function is required. Despite E. acervulina primarily targeting the duodenum, our findings demonstrate the infection can impact bacterial diversity and abundance in the cecal and ileal microbiota.

The New Buffer Salt-Protected Sodium Butyrate Promotes Growth Performance by Improving Intestinal Histomorphology, Barrier Function, Antioxidative Capacity, and Microbiota Community of Broilers

In this study, a commercial sodium butyrate protected by a new buffer salt solution (NSB) was tested to determine whether it can be used as an antibiotic alternative in broiler production. A total of 192 1-day-old broilers were randomly allocated to three dietary treatments: soybean meal diet (CON), antibiotic diet (ANT, basal diet + 100 mg/kg aureomycin), and NSB (basal diet + 800 mg/kg NSB). The growth performance, serum anti-inflammatory cytokines, intestinal morphology, gut barrier function, antioxidative parameters, SCFAs' content, and cecal microbiota were analyzed. The result showed that NSB significantly improved ADFI and ADG (p < 0.01), and decreased FCR (p < 0.01). Serum anti-inflammatory cytokine IL-10 was up-regulated (p < 0.01), and pro-inflammatory TNF-α was down-regulated (p < 0.05) by NSB supplementation. H&E results showed that VH and the VH/CD ratio significantly increased (p < 0.05) in the jejunum and ileum in the NSB group. Furthermore, ZO-1 (p < 0.01), claudin-1 (p < 0.01), and occludin (p < 0.05) in the jejunum and claudin-1 (p < 0.01) and mucin-2 (p < 0.05) in the ileum were significantly up-regulated in the NSB group. Additionally, SOD (p < 0.05) and the T-AOC/MDA ratio (p < 0.01) in the jejunum and SOD in the ileum were significantly increased (p < 0.05) in the NSB group. The MDA level also significantly increased (p < 0.01) in the ANT group in the jejunum. Propionic acid (p < 0.05) and butyric acid (p < 0.01) content significantly increased in the NSB group in the jejunum and ileum segments. The 16S rRNA sequencing results showed no significant difference (p > 0.05) in alpha and beta diversity among the groups. LEFSe analysis also indicated that Peptostreptococcaceae, Colidextribacter, Firmicutes, Oscillospira, and Erysipelatoclostridiaceae, which promote SCFA production (p < 0.05), were identified as dominant taxon-enriched bacterial genera in the NSB group. The Spearman correlation analysis revealed that Colidextribacter with ADFI, ADG, VH, claudin-1 (p < 0.05), and unclassified_f__Peptostreptococcaceae with ADFI, IL-10, and ZO-1 were positively correlated (p < 0.05). Furthermore, ADFI and ADG with IL-10, claudin-1, SOD, T-AOC, and butyric acid (p < 0.05), and similarly, ADG with VH (p < 0.05), showed a positive correlation. In conclusion, NSB enhanced the growth performance by improving jejunum and ileum morphology, and serum anti-inflammatory cytokines, and by regulating the intestinal barrier function and antioxidant capacity, SCFAs' content, and cecum microbiota, showing its potential use as an alternative to antibiotics in poultry nutrition.

Effects of coated sodium butyrate on the growth performance, serum biochemistry, antioxidant capacity, intestinal morphology, and intestinal microbiota of broiler chickens

Introduction

This study examined the impact of adding coated sodium butyrate (CSB) to the diet on the growth performance, serum biochemistry, antioxidant capacity, intestinal morphology, and cecal microbiota of yellow-feathered broiler chickens.

Methods

In this study, 240 yellow-feathered broiler chickens at 26 days old were divided into two groups: the control group (CON group) received a standard diet, and the experimental group (CSB group) received a diet with 0.5 g/kg of a supplement called CSB. Each group had 6 replicates, with 20 chickens in each replicate, and the experiment lasted for 36 days.

Results

Compared to the CON group, the CSB group showed a slight but insignificant increase in average daily weight gain during the 26-62 day period, while feed intake significantly decreased. The CSB group exhibited significant increases in serum superoxide dismutase, catalase, and total antioxidant capacity. Additionally, the CSB group had significant increases in total protein and albumin content, as well as a significant decrease in blood ammonia levels. Compared to the CON group, the CSB group had significantly increased small intestine villus height and significantly decreased jejunal crypt depth. The abundance of Bacteroidetes and Bacteroides in the cecal microbiota of the CSB group was significantly higher than that of the CON group, while the abundance of Proteobacteria, Deferribacteres, and Epsilonbacteraeota was significantly lower than that of the CON group.

Conclusion

These results suggest that adding CSB to the diet can improve the growth performance and antioxidant capacity of yellow-feathered broiler chickens while maintaining intestinal health.

Effects of Dietary Terminalia chebula Extract on Growth Performance, Immune Function, Antioxidant Capacity, and Intestinal Health of Broilers

Terminalia chebula extract (TCE) has many physiological functions and is potentially helpful in maintaining poultry health, but its specific effect on the growth of broilers is not yet known. This research investigated the effects of dietary Terminalia chebula extract (TCE) supplementation on growth performance, immune function, antioxidant capacity, and intestinal health in yellow-feathered broilers. A total of 288 one-day-old yellow-feathered broilers were divided into four treatment groups (72 broilers/group), each with six replicates of 12 broilers. The broilers were given a basal diet of corn-soybean meal supplemented with 0 (control), 200, 400, and 600 mg/kg TCE for 56 d. The results demonstrated that, compared with the basal diet, the addition of TCE significantly increased (linear and quadratic, p < 0.05) the final body weight and overall weight gain and performance and decreased (linear and quadratic, p < 0.05) the feed-to-gain ratio in the overall period. Dietary TCE increased (linear, p < 0.05) the levels of IgM, IL-4, and IL-10 and decreased (linear and quadratic, p < 0.05) the level of IL-6 in the serum. Dietary TCE increased (linear and quadratic, p < 0.05) the levels of IL-2 and IL-4, decreased (linear and quadratic, p < 0.05) the level of IL-1β, and decreased (linear, p < 0.05) the level of IL-6 in the liver. Dietary TCE increased (linear and quadratic, p < 0.05) the level of IgM and IL-10, increased (linear, p < 0.05) the level of IgG, and decreased (linear and quadratic, p < 0.05) the levels of IL-1β and IL-6 in the spleen. Supplementation with TCE linearly and quadratically increased (p < 0.05) the catalase, superoxide dismutase, glutathione peroxidase, and total antioxidant capacity activities while decreasing (p < 0.05) the malonic dialdehyde concentrations in the serum, liver, and spleen. TCE-containing diets for broilers resulted in a higher (linear and quadratic, p < 0.05) villus height, a higher (linear and quadratic, p < 0.05) ratio of villus height to crypt depth, and a lower (linear and quadratic, p < 0.05) crypt depth compared with the basal diet. TCE significantly increased (linear, p < 0.05) the acetic and butyric acid concentrations and decreased (quadratic, p < 0.05) the isovaleric acid concentration. Bacteroidaceae and Bacteroides, which regulate the richness and diversity of microorganisms, were more abundant and contained when TCE was added to the diet. In conclusion, these findings demonstrate that supplementing broilers with TCE could boost their immune function, antioxidant capacity, and gut health, improving their growth performance; they could also provide a reference for future research on TCE.

Dietary Qi-Weng-Huangbo powder enhances growth performance, diarrhoea and immune function of weaned piglets by modulating gut health and microbial profiles

Introduction

The evolution of nutritional strategies to improve the gut health and microbiota profiles of early-weaned piglets is essential to reduce diarrhoea caused by weaning stress. Therefore, the aim of this study was to determine the effects of dietary supplementation of Qi-Weng-Huangbo powder, a traditional herbal medicine consisting of a mixture of Pulsatilla chinensis, Chinese Schneid and Astragalus extracts (PCE), on the growth performance, diarrhoea rate, immune function and intestinal health of weaned piglets.

Methods

162 piglets were randomly assigned to the CON group (no PCE added), the PCEL group (300 mg/kg PCE) and the PCEH group (500 mg/kg PCE) at the end of the third week post farrowing. There were 9 replicates of each group with 6 pigs per replicate. The experiment lasted for 28 days and sampling was performed on the final day.

Results

The results showed that the PCE diet increased the average daily gain (ADG) and final body weight (BW) compared to the CON group. Both supplemented doses of PCE reduced the faecal scores of piglets, and the diarrhoea rate in the PCEL group was significantly lower than that in the CON group. The application of PCE diets promoted the development of the spleen in piglets and up-regulated serum immunoglobulin concentrations to enhance immune function, which was also reflected in the down-regulated gene expression of the colonic TLR/MyD88/NF-κB pathway. Supplementation with PCE improved intestinal morphology, and all doses of PCE significantly increased villus height (VH) in the ileum, whereas colonic crypt depth (CD) was significantly lower in the PCEH group than in the CON group. The PCEH diet significantly increased the levels of valeric and isovaleric acid in the colon content. Dietary PCEH also improved the colonic microbial community profile, reflected by a significant increase in Shannon's index compared with CON group. The abundance of Veillonellaceae and Rhodospirillales was significantly increased in the PCEH group at the family level.

Discussion

In conclusion, dietary PCE reduced diarrhoea rates, improved growth performance and enhanced immune function in weaned piglets. These improvements were potentially supported by altered ileum and colonic morphology, elevated colonic VFA levels, and modulation of colonic microbial profiles.

Microbiota-Induced Epigenetic Alterations in Depressive Disorders Are Targets for Nutritional and Probiotic Therapies

Major depressive disorder (MDD) is a complex disorder and a leading cause of disability in 280 million people worldwide. Many environmental factors, such as microbes, drugs, and diet, are involved in the pathogenesis of depressive disorders. However, the underlying mechanisms of depression are complex and include the interaction of genetics with epigenetics and the host immune system. Modifications of the gut microbiome and its metabolites influence stress-related responses and social behavior in patients with depressive disorders by modulating the maturation of immune cells and neurogenesis in the brain mediated by epigenetic modifications. Here, we discuss the potential roles of a leaky gut in the development of depressive disorders via changes in gut microbiota-derived metabolites with epigenetic effects. Next, we will deliberate how altering the gut microbiome composition contributes to the development of depressive disorders via epigenetic alterations. In particular, we focus on how microbiota-derived metabolites such as butyrate as an epigenetic modifier, probiotics, maternal diet, polyphenols, drugs (e.g., antipsychotics, antidepressants, and antibiotics), and fecal microbiota transplantation could positively alleviate depressive-like behaviors by modulating the epigenetic landscape. Finally, we will discuss challenges associated with recent therapeutic approaches for depressive disorders via microbiome-related epigenetic shifts, as well as opportunities to tackle such problems.

Restorative effects of Lactobacillus rhamnosus LR-32 on the gut microbiota, barrier integrity, and 5-HT metabolism in reducing feather-pecking behavior in laying hens with antibiotic-induced dysbiosis

The development of abnormal feather-pecking (FP) behavior, where laying hens display harmful pecks in conspecifics, is multifactorial and has been linked to the microbiota-gut-brain axis. Antibiotics affect the gut microbial composition, leading to gut-brain axis imbalance and behavior and physiology changes in many species. However, it is not clear whether intestinal dysbacteriosis can induce the development of damaging behavior, such as FP. The restorative effects of Lactobacillus rhamnosus LR-32 against intestinal dysbacteriosis-induced alternations need to be determined either. The current investigation aimed to induce intestinal dysbacteriosis in laying hens by supplementing their diet with the antibiotic lincomycin hydrochloride. The study revealed that antibiotic exposure resulted in decreased egg production performance and an increased tendency toward severe feather-pecking (SFP) behavior in laying hens. Moreover, intestinal and blood-brain barrier functions were impaired, and 5-HT metabolism was inhibited. However, treatment with Lactobacillus rhamnosus LR-32 following antibiotic exposure significantly alleviated the decline in egg production performance and reduced SFP behavior. Lactobacillus rhamnosus LR-32 supplementation restored the profile of the gut microbial community, and showed a strong positive effect by increasing the expression of tight junction proteins in the ileum and hypothalamus and promoting the expression of genes related to central 5-HT metabolism. The correlation analysis revealed that probiotic-enhanced bacteria were positively correlated, and probiotic-reduced bacteria were negatively correlated with tight junction-related gene expression, and 5-HT metabolism, and butyric acid levels. Overall, our findings indicate that dietary supplementation with Lactobacillus rhamnosus LR-32 can reduce antibiotic-induced FP in laying hens and is a promising treatment to improve the welfare of domestic birds.