Effects of dietary palygorskite supplementation on the growth performance, oxidative status, immune function, intestinal barrier and cecal microbial community of broilers

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 %.

Exploring the Mechanism of Clostridium autoethanogenum Protein for Broiler Growth Based on Gut Microbiota and Serum Metabolomics

Intestinal health is vital for poultry production, and protein plays a key role in intestinal nutrition. The present study used 16S rRNA gene sequencing and serum metabolomics to investigate the effect of CAP on the cecal microflora structure and serum metabolites in 42-day-old broiler chickens. A total of 480 one-day-old Arbor Acres broiler chickens were randomly divided into four treatments with twelve replicates comprising 10 chickens each, evenly divided by sex. The four groups were basal diet group (CAP0), treatment group 1 (CAP2), treatment group 2 (CAP3), and treatment group 3 (CAP4). The broilers in the CAP0 group were fed a basal diet (without CAP), while those in the CAP2, CAP3, and CAP4 groups received diets containing 2%, 3%, and 4% CAP, respectively. Growth performance results showed that dietary CAP supplementation significantly ameliorated the feed conversion rate (FCR) of broilers at 42 days in the CAP3 and CAP4 groups (p < 0.05). Microbial results revealed that CAP did not alter the dominant microorganisms in the cecum at the phylum, family, and genus levels. LEfSe analysis showed significantly higher relative abundances of p_Desulfobacterota, f_Desulfovibrionaceae, and g_Ruminococcus in the CAP3 group compared to the CAP0 and CAP4 groups. Metabolomic analyses indicated that the effect of incorporating CAP into the diet on serum metabolites primarily focused on organic acids and their derivatives, small peptides, amino acid derivatives, and oxidized lipids. The addition of 3% or 4% CAP to the diet can enhance metabolic pathways such as the citrate cycle (TCA cycle) and arginine and proline metabolism. In summary, incorporating CAP into the diet can increase the relative abundance of beneficial bacteria in the cecum and improve the feed conversion efficiency of broilers by enhancing amino acid and energy metabolism.

Impacts of ectoparasite flea infestation on gut microbiota of the Meriones unguiculatus in a rodent-flea system

Fleas, along with one of their host species, Meriones unguiculatus, possess the capability to act as vectors in the transmission of plague. Parasitism by fleas may markedly influence the physiology and immune system of their hosts. Gut microbiota plays an important role in the growth and development of rodents. However, few studies have explored the impacts of ectoparasitic flea on the gut microbiome of rodents. This study investigated the immunological responses and changes in the gut microbial diversity and composition in both wild and laboratory rodents infested with fleas and laboratory rodents infested with Ctenocephalides felis. We measured immune reactions post-infestation by enzyme-linked immunosorbent assay (ELISA) and explored the effects of ectoparasitic infestation on the diversity and composition of the rodent gut microbiota in microbiome studies by 16S rRNA gene sequencing techniques. After flea infestation, results from 16S rRNA gene sequencing techniques indicated a significant increase in alpha diversity, affecting the composition of the gut microbiota. At the genus level, the abundance of the harmful bacterium Desulfovibrio increased. Beta diversity analyses showed significant differences between the gut microbiota of the experimental and control groups. ELISA results revealed significantly elevated levels of IgG in parasitized mice, while the differences in IgA levels were not significant. Flea infections affect the composition and diversity of the gut microbiota in the M. unguiculatu, and it has been found that the biomarker Desulfovibrio increases following flea infection in these rodents. Our results indicate that the gut microbiota can regulate the stability of the rodent-flea system. These findings may provide a foundation for exploring preventive measures against plague and aid in developing more effective treatments for the infection.

Dietary supplementation with a silicate clay mineral (palygorskite) alleviates inflammatory responses and intestinal barrier damage in broiler chickens challenged with Escherichia coli

This experiment aimed to explore the protective effects of dietary palygorskite (Pal) supplementation on inflammatory responses and intestinal barrier function of broiler chickens challenged with Escherichia coli (E. coli). A 2 × 2 factorial arrangement was designed to assess the effects of Pal administration (0 or 5 g/kg of feed) and E. coli challenge (E. coli or bacterial culture medium) on broilers in a 21-d feeding trial. Birds were randomly assigned into one of the 4 groups, and each group had 8 replicates with ten birds each. The challenged chickens were orally gavaged with E. coli suspended in Luria-Bertani broth on 14 d of age, while unchallenged birds were administrated with an equivalent amount of culture medium. The sampling was performed at 21 d of age. Compared with the normal birds, an oral E. coli challenge reduced final body weight, and decreased feed intake, weight gain, and feed efficiency during the challenge period (P < 0.05). E. coli challenge promoted colonization of E. coli in cecal content and their translocation to internal organs (heart, liver, and spleen) (P < 0.05). E. coli infection also increased levels of pro-inflammatory cytokines in jejunum and ileum possibly through activating the toll-like receptor-4-mediated signaling pathway (P < 0.05). Moreover, E. coli administration increased intestinal mucosal permeability (higher serum D-lactate level and diamine oxidase activity, and lower intestinal mucosal disaccharidase activities), altered intestinal morphology, and downregulated the gene expression of intestinal tight junction proteins (P < 0.05). In contrast, Pal supplementation enhanced growth performance, inhibited colonization of E. coli, reduced intestinal inflammation, decreased intestinal permeability, restored intestinal morphology, and normalized the expression of genes responsible for inflammatory processes and maintenance of intestinal mucosal barrier (P < 0.05), and most of these beneficial effects resulting from Pal administration were independent of bacterial challenge. The results indicated dietary Pal incorporation was effective in improving growth performance and alleviating inflammation and intestinal mucosal barrier damage in broilers challenged with E. coli.

Recent advances in the application of clay-containing hydrogels for hemostasis and wound healing

INTRODUCTION

Immediate control of bleeding and anti-infection play important roles in wound management. Multiple organ dysfunction syndrome and death may occur if persistent bleeding, hemodynamic instability, and hypoxemia are not addressed. The combination of clay and hydrogel provides a new outlet for wound hemostasis. In this review, the current research progress of hydrogel/clay composite hemostatic agents was reviewed.

AREAS COVERED

This paper summarizes the characteristics of several kinds of clay including kaolinite, montmorillonite, laponite, sepiolite, and palygorskite. The advantages and disadvantages of its application in hemostasis were also summarized. Future directions for the application of hydrogel/clay composite hemostatic agents are presented.

EXPERT OPINION

Clay can activate the endogenous hemostatic pathway by increasing blood cell concentration and promoting plasma absorption to accelerate the hemostasis. Clay is antimicrobial due to the slow release of metal ions and has a rich surface charge with a high affinity for proteins and cells to promote tissue repair. Hydrogels have some properties such as good biocompatibility, strong adhesion, high stretchability, and good self-healing. Despite promising advances, hydrogel/clay composite hemostasis remains a limitation. Therefore, more evidence is needed to further elucidate the risk factors and therapeutic effects of hydrogel/clay in hemostasis and wound healing.

Palygorskite improves growth performance and prevents liver damage in avian pathogenic Escherichia coli-challenged broiler chickens at an early age

Avian pathogenic Escherichia coli (APEC) is a major bacterial infection that causes economic losses in the global poultry industry. Palygorskite (PAL) has been shown to enhance growth performance while improving antioxidative and anti-inflammatory properties of broilers. This study evaluated the protective effects of PAL on growth performance and liver function in broilers subjected to APEC challenge. A total of 320 one-day-old male Arbor Acres chicks were divided into 4 groups with 8 replicates of 10 birds each, based on a 2 × 2 factorial arrangement (basal diet or 5 g/kg PAL-supplemented diet) and inoculation (bacterial culture medium or APEC). PAL increased body weight gain (BWG) prior to APEC challenge (P < 0.05). However, APEC caused losses in BWG, feed intake (FI), and feed efficiency, along with increased relative hepatic weight, hepatic pathology scores, and hepatic-cell apoptosis rate (P < 0.05). Compared to normal birds, APEC increased interleukin (IL)-1β, interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), malondialdehyde (MDA), and nitric oxide (NO) levels, as well as lysozyme (LZM) and myeloperoxidase (MPO) activities, while decreasing total antioxidant capacity (T-AOC) and IL-10 levels, and total superoxide dismutase (T-SOD) and catalase (CAT) activities in both serum and liver, APEC also raised alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, but reduced total protein (TP), albumin (ALB), immunoglobulin (Ig) A, IgG, and IgM levels in serum (P < 0.05). Moreover, APEC increased hepatic mRNA level of IL-1β, IFN-γ, TNF-α, nuclear factor kappa B, and inducible nitric oxide synthase (iNOS), while inhibited mRNA level of IL-10 (P < 0.05). In contrast, PAL increased BWG and FI, and alleviated hepatic-cell apoptosis rate during the challenge period (P < 0.05). Incorporation of PAL reduced triglyceride and NO contents, ALT, and AST activities, while increasing TP, ALB, IL-10, IgG, and IgM levels in serum, enhancing serum T-SOD and CAT activities, elevating hepatic T-AOC and CAT activities, inhibiting hepatic MDA accumulation, and reducing IL-1β levels and LZM activity in both liver and serum (P < 0.05). An interactive effect was found for hepatic TNF-α and iNOS mRNA expression, in which PAL inhibited their mRNA expression in APEC-challenged birds (P < 0.05). Overall, PAL addition partially mitigated the negative impact of the APEC challenge on the growth performance and liver function of broiler chicks at an early age.