Dietary resistant starch alleviates Escherichia coli-induced bone loss in meat ducks by promoting short-chain fatty acid production and inhibiting Malt1/NF-κB inflammasome activation

The protective effects of dietary resistant starch against post-antibiotic bone loss in meat ducks associated with the recovery of caecal microbiota dysbiosis

Compromised bone quality increases the risk of fractures in domesticate birds, resulting in pain and altered behaviour. Although dietary resistant starch (RS) supplementation show promise for improving inferior bone mass, the diet-mediated gut microbiota alterations as a potential mechanism underlying RS positive roles in bone remains uncertain. With a post-antibiotic model and faecal microbiota transplantation (FMT), this study investigated the effects of a RS diet on antibiotic-induced bone loss and gut microbial composition in meat ducks. Ducklings were assigned to 4 treatments with 6 replicate pens until 21 d, including the control group (Ctrl, feeding a basal diet) and the RS-fed group, and post-antibiotic treatment following the gavage of phosphate-buffered saline (Post-anti-PBS) or faecal microbiota transplantation (Post-anti-FMT). The RS diet increased the proportion of Firmicutes, improved intestinal integrity, and reduced inflammation-induced bone resorption, all of which contributed to an increase in tibial bone volume (P < 0.05). Post-antibiotic treatment was found to reduce tibial quality by stimulating bone resorption and inhibiting bone formation, accompanied by gut microbiota dysbiosis, increased intestinal permeability (P = 0.059), and inflammatory flare compared to control birds. FMT from RS-fed ducks into the antibiotic-treated birds reversed bone loss by primarily blocking osteoclastic frequency and activity. Furthermore, FMT increased the ratio of Firmicutes to Bacteroidetes (P < 0.05) and suppressed the release of pro-osteoclastogenic cytokines such as tumour necrosis factor-α (P = 0.062) and interleukin-1β (P < 0.05) in the bone marrow. These results demonstrated the involvement of gut microbiota in improving bone quality of meat ducks by RS, and FMT of RS-fed birds corrected the imbalance of ceca microbiota and attenuated bone loss in meat ducks with enhanced bone resorption.

Dietary resistant starch protects against post-antibiotic intestinal damage by restoring microbial homeostasis and preserving intestinal barrier function in meat duck

Resistant starch (RS) is recognized as a nutritional strategy that supports gut and overall host health by modulating gut microbiota. To directly assess the effects of RS on gut microbiota and its role in improving intestinal barrier function in meat ducks, this study first established an antibiotic-induced microbial dysbiosis model, which was characterized by reduced gut microbial diversity, intestinal dysfunction, and an inflammatory outburst following antibiotic exposure. Whereafter, in addition to the control group, ducks treated with antibiotics for 7 consecutive days were further allocated to two groups and fed the basal diet and RS diet that derived from 12 % raw potato starch until 21 d. The results demonstrated that dietary RS supplementation reversed the antibiotic-induced reduction in microbial diversity and restored the Firmicutes-to-Bacteroidetes ratio. Additionally, RS inclusion enriched beneficial bacterial genera, including Coprobacter, Odoribacter, and Faecalibacterium (LDA score > 3). Post-antibiotic intervention led to a reduction in villus density and muscular thickness, accompanied by a significant downregulation (P < 0.05) of zonula occludens-1 and mucin-2 expression, along with increased serum pro-inflammatory cytokine levels (P < 0.05). Notably, dietary RS supplementation significantly enhanced (P < 0.05) the expression of glucagon-like peptide receptor and the anti-apoptotic factor Bcl-2, while suppressing caspase transcription. This resulted in increased villus height and muscular thickness in the ileum (P < 0.05). Furthermore, RS intervention remarkably reduced (P < 0.05) pro-inflammatory cytokine levels, particularly interleukin-1β and tumor necrosis factor-α, in both the ileum and serum. These effects were likely linked to alterations in cecal microbiota, including increased abundances of Barnesiella, Ruminiclostridium 9, Megamonas, Faecalitalea, Adlercreutzia, Coprobacter and Collinsella. In conclusion, dietary RS supplementation mitigated antibiotic-induced cecal microbial dysbiosis and restored intestinal structure by promoting enterocyte proliferation and reducing apoptosis. Consequently, RS supplementation helped alleviate systemic inflammation in meat ducks following antibiotic treatment.

Gut-X Axis and Its Role in Poultry Bone Health: A Review

The normal development and growth of bones are critical for poultry health. With the rapid increase in poultry growth rates achieved over the last few decades, juvenile meat-type poultry exhibit a high incidence of leg weakness and lameness. These issues are significant contributors to poor animal welfare and substantial economic losses. Understanding the potential etiology of bone problems in poultry will aid in developing treatments for bone diseases. The gut microbiota represents the largest micro-ecosystem in animals and is closely related to many metabolic disorders, including bone disease. It achieves this by secreting secondary metabolites and coordinating with various tissues and organs through the circulatory system, which leads to the concept of the gut-X axis. Given its importance, modulating gut microbiota to influence the gut-X axis presents new opportunities for understanding and developing innovative therapeutic approaches for poultry bone diseases. In light of the extensive literature on this topic, this review focuses on the effects of gut microbiota on bone density and strength in poultry, both directly and indirectly, through the regulation of the gut-X axis. Our aim is to provide scientific insights into the bone health problems faced by poultry.

Effect of intestinal microbiota on duck short-beak and dwarf syndrome caused by novel goose parvovirus

Short-beak and dwarf syndrome (SBDS) is caused by infection with novel goose parvovirus (NGPV), which leads to intestinal dysbiosis, developmental delay, short beak, lameness, and paralysis in ducks and is the cause of skeletal health problems. NGPV infection can cause intestinal microbial disturbances, but it is still unclear whether the intestinal microbiota affects the pathogenicity of NGPV. Here, the effects of intestinal microbiota on NGPV-induced SBDS in Cherry Valley ducks were assessed by establishing a duck model for gut microflora depletion/reestablishment through antibiotics (ABX) treatment/fecal microbiota transplanted (FMT). By measuring body weight, beak length, beak width and tarsal length, we found that SBDS clinical symptoms were alleviated in ducks treated with ABX, but not in FMT ducks. Next, we conducted a comprehensive analysis of bone metabolism, gut barrier integrity, and inflammation levels using quantitative real-time PCR (qPCR), enzyme linked immunosorbent assay (ELISA), biochemical analysis and histological analysis. The results showed that ABX treatment improved bone quality reduced bone resorption, mitigated tissue lesions, protected intestinal barrier integrity, and inhibited systemic inflammation in NGPV-infected ducks. Moreover, cecal microflora composition and short-chain fatty acids (SCFAs) production were examined by bacterial 16S rRNA sequencing and gas chromatography. The results revealed that ABX treatment mitigated the decreased abundance of Firmicutes and Bacteroidota in NGPV-infected ducks, as well as increased SCFAs production. Furthermore, ABX treatment reduced the mucosa-associated lymphoid tissue lymphoma translocation protein 1 (Malt1) and nuclear factor κB (NF-κB) expression, which are correlated with systemic inflammation in SBDS ducks. These findings suggested that intestinal microflora depletion alleviated NGPV-induced SBDS by maintaining intestinal homeostasis, inhibiting inflammatory response and alleviating bone resorption. These results provide evidence for the pivotal role of intestinal microbiota in the process of SBDS and contribute a theoretical basis for the feasibility of microecological preparation as a method to control SBDS.

Mulberry Leaf Dietary Supplementation Can Improve the Lipo-Nutritional Quality of Pork and Regulate Gut Microbiota in Pigs: A Comprehensive Multi-Omics Analysis

Mulberry leaves, a common traditional Chinese medicine, represent a potential nutritional strategy to improve the fat profile, also known as the lipo-nutrition, of pork. However, the effects of mulberry leaves on pork lipo-nutrition and the microorganisms and metabolites in the porcine gut remain unclear. In this study, multi-omics analysis was employed in a Yuxi black pig animal model to explore the possible regulatory mechanism of mulberry leaves on pork quality. Sixty Yuxi black pigs were divided into two groups: the control group (n = 15) was fed a standard diet, and the experimental group (n = 45) was fed a diet supplemented with 8% mulberry leaves. Experiments were performed in three replicates (n = 15 per replicate); the two diets were ensured to be nutritionally balanced, and the feeding period was 120 days. The results showed that pigs receiving the diet supplemented with mulberry leaves had significantly reduced backfat thickness (p < 0.05) and increased intramuscular fat (IMF) content (p < 0.05) compared with pigs receiving the standard diet. Lipidomics analysis showed that mulberry leaves improved the lipid profile composition and increased the proportion of triglycerides (TGs). Interestingly, the IMF content was positively correlated with acyl C18:2 and negatively correlated with C18:1 of differential TGs. In addition, the cecal microbiological analysis showed that mulberry leaves could increase the abundance of bacteria such as UCG-005, Muribaculaceae_norank, Prevotellaceae_NK3B31_group, and Limosilactobacillus. Simultaneously, the relative levels of L-tyrosine-ethyl ester, oleic acid methyl ester, 21-deoxycortisol, N-acetyldihydrosphingosine, and mulberrin were increased. Furthermore, we found that mulberry leaf supplementation significantly increased the mRNA expression of lipoprotein lipase, fatty acid-binding protein 4, and peroxisome proliferators-activated receptor γ in muscle (p < 0.01). Mulberry leaf supplementation significantly increased the mRNA expression of diacylglycerol acyltransferase 1 (p < 0.05) while significantly decreasing the expression of acetyl CoA carboxylase in backfat (p < 0.05). Furthermore, mulberry leaf supplementation significantly upregulated the mRNA expression of hormone-sensitive triglyceride lipase and peroxisome proliferator-activated receptor α (p < 0.05) in backfat. In addition, mulberry leaf supplementation led to increased serum leptin and adiponectin (p < 0.01). Collectively, this omic profile is consistent with an increased ratio of IMF to backfat in the pig model.

Lachnospiraceae-derived butyrate mediates protection of high fermentable fiber against placental inflammation in gestational diabetes mellitus

Inflammation-associated insulin resistance is a key trigger of gestational diabetes mellitus (GDM), but the underlying mechanisms and effective interventions remain unclear. Here, we report the association of placental inflammation (tumor necrosis factor-α) and abnormal maternal glucose metabolism in patients with GDM, and a high fermentable dietary fiber (HFDF; konjac) could reduce GDM development through gut flora-short-chain fatty acid-placental inflammation axis in GDM mouse model. Mechanistically, HFDF increases abundances of Lachnospiraceae and butyrate, reduces placental-derived inflammation by enhancing gut barrier and inhibiting the transfer of bacterial-derived lipopolysaccharide, and ultimately resists high-fat diet-induced insulin resistance. Lachnospiraceae and butyrate have similar anti-GDM and anti-placental inflammation effects, and they can ameliorate placental function and pregnancy outcome effects probably by dampening placental immune dysfunction. These findings demonstrate the involvement of important placental inflammation-related mechanisms in the progression of GDM and the great potential of HFDFs to reduce susceptibility to GDM through gut-flora-placenta axis.