Cecal Microbiota Modulates Fat Deposition in Muscovy Ducks

Effects of different photoperiods on melatonin level, cecal microbiota and breast muscle morphology of broiler chickens

Long photoperiods are often characterized by enhanced oxidative stress-induced damage to skeletal muscle, reduced melatonin (MT) levels and intestinal microbiota dysfunction in broilers. In this study, we aimed to investigate the association of breast muscle morphology with melatonin levels and the cecal microbiota of broilers under different photoperiods. A total of 216 healthy 5-day-old Arbor Acres (AA) male broilers were randomly assigned to 12 L:12D, 18 L:6D and 24 L:0D photoperiods for 4 weeks (L = hours of light, D = hours of darkness). The concentration of inflammatory factors and MT concentrations was measured using ELISA kits, whereas breast muscle morphology was examined through the hematoxylin (H) and eosin (E) staining, and microbiota composition was identified through 16 s rRNA analysis. Extended light exposure significantly improved the growth rate of broilers, but significantly decreased feed efficiency (FE). Furthermore, it upregulated the concentration of IL-1β, IL-6 and TNF-α and induced an abnormal breast muscle morphology. Extended light exposure significantly decreased MT levels in the hypothalamus, cecum and breast muscle, while triggering the cecal microbiota composition disorder. Specifically, there was significant alteration to the dominant bacterial phylum, following exposure to long photoperiods, with the abundance of Firmicutes decreasing and the abundance of Bacteroidota increasing. Notably, the relative abundance of Lactobacillus showed a positive correlation with MT levels and a negative correlation with inflammatory cytokines. In conclusion, the present findings indicated that extended light exposure reduced the MT levels, which were related to disturbed cecal microbiota, damaging breast muscle morphology and inducing breast muscle inflammation in broilers.

Microbiome-metabolomics analysis insight into the effects of dietary chromium picolinate on abdominal fat deposition and lipid metabolism of ducks

This research endeavored to explore the impact of Cr-Pic on the abdominal fat deposition and lipid metabolism of ducks, as well as to uncover the mechanisms at play and identify the optimal dietary supplementation level of Cr-Pic. The results showed that adding 0.6 mg/kg Cr-Pic observably increased the body weight and serum levels of adiponectin and leptin, and decreased serum levels of total cholesterol, triglyceride, and low-density lipoprotein cholesterol in ducks at 14 days (P < 0.05). The addition of 0.6 % Cr-Pic was discovered to regulate lipid metabolism and meat quality through its effects on reducing abdominal fat and drip loss, downregulating the mRNA expression of genes involved in lipid synthesis in the abdominal fat and liver, and upregulating the mRNA expression of genes associated with degradation and transport in these tissues (P < 0.05). Untargeted metabolic profiling indicated that the distinct metabolites between the Cr-Pic and Control groups were predominantly associated with pathways involving amino acids. Microbiome analysis showed that Cr-Pic administration altered the microbial genera related to the adjustment of lipid metabolism in the cecum of ducks, such as increasing the proportion of Bacteroides and Lactobacillus, and decreasing the proportions of Alistipes, Methanobrevibacter, Romboutsia, and Peptostreptococcus (P < 0.05). In summary, Cr-Pic shows promise in reducing the abdominal fat accumulation in ducks by regulating the intestinal microbial composition and the metabolic pathways of amino acids that are linked to lipid metabolism.

The Interactive Effects of Nutrient Density and Breed on Growth Performance and Gut Microbiota in Broilers

This study investigated whether variations in growth response to low nutrient density across breeds are linked to microbiota regulation. Arbor Acres (AA) and Beijing-You (BY) were fed high- (HN) and low-nutrient (LN) diets from day (d) 0 to d42. Body weight, feed intake, and intestinal measurements were recorded, and microbiota from the ileum and cecum were analyzed on d7, d21, and d42. Results showed that AA broilers had greater growth performance with a lower feed conversion ratio (FCR) and greater average daily gain (ADG) than BY chickens. The LN diet negatively affected AA broiler growth due to impaired intestinal development, while BY chickens compensated by increasing feed intake. Microbiota composition was primarily affected by breed than by nutrient density, with AA broilers having more beneficial bacteria and BY chickens having more short-chain fatty acid (SCFA)-producing bacteria. The LN diets reduced anti-inflammatory bacteria such as Shuttleworthia and Eisenbergiella in the cecum on d7. By d21, LN diets decreased Lactobacillus and increased proinflammatory Marvinbryantia, potentially impairing growth. However, LN diets enriched SCFA-producing bacteria like Ruminococcaceae_UCG.013, Eisenbergiella, and Tyzzerella in BY chickens and Faecalitalea in AA broilers by d21, which may benefit gut health. By d42, LN diets reduced genera linked to intestinal permeability and fat deposition, including Ruminococcus_torques_group, Romboutsia, Erysipelatoclostridium, and Oscillibacter. Additionally, LN diets enriched Christensenellaceae_R-7_group in AA broilers, associated with intestinal barrier integrity, and increased anti-inflammatory bacteria Alistipes and Barnesiella in AA broilers and BY chickens, respectively, by d42. Overall, AA broilers were more susceptible to reduced nutrient density due to impaired intestinal development, while BY chickens adapted better by increasing feed intake. The microbiota responses to low nutrient density varied over time, potentially negatively affecting gut health in the early stage and growth in the middle stage but possibly improving lipid deposition and gut health in the middle and late stages.

Linking growth performance and carcass traits with enterotypes in Muscovy ducks

OBJECTIVE

Enterotypes (ETs) are the clustering of gut microbial community structures, which could serve as indicators of growth performance and carcass traits. However, ETs have been sparsely investigated in waterfowl. The objective of this study was to identify the ileal ETs and explore the correlation of the ETs with growth performance and carcass traits in Muscovy ducks.

METHODS

A total of 200 Muscovy ducks were randomly selected from a population of 5,000 ducks at 70-day old, weighed and slaughtered. The growth performance and carcass traits, including body weight, dressed weight and evidenced weight, dressed percentage, percentage of apparent yield, breast muscle weight, leg muscle weight, percentage of leg muscle and percentage of breast muscle, were determined. The contents of ileum were collected for the isolation of DNA and 16S rRNA gene sequencing. The ETs were identified based on the 16S rRNA gene sequencing data and the correlation of the ETs with growth performance and carcass traits was performed by Spearman correlation analysis.

RESULTS

Three ETs (ET1, ET2, and ET3) were observed in the ileal microbiota of Muscovy ducks with significant differences in number of features and α-diversity among these ETs (p<0.05). Streptococcus, Candida Arthritis, and Bacteroidetes were the presentative genus in ET1 to ET3, respectively. Correlation analysis revealed that Lactococcus and Bradyrhizobium were significantly correlated with percentage of eviscerated yield and leg muscle weight (p<0.05) while ETs were found to have a close association with percentage of eviscerated yield, leg muscle weight, and percentage of leg muscle in Muscovy ducks. However, the growth performance of ducks with different ETs did not show significant difference (p>0.05). Lactococcus were found to be significantly correlated with leg muscle weight, dressed weight, and percentage of eviscerated yield.

CONCLUSION

Our findings revealed a substantial variation in carcass traits associated with ETs in Muscovy ducks. It is implied that ETs might have the potential to serve as a valuable biomarker for assessing duck carcass traits. It would provide novel insights into the interaction of gut microbiota with growth performance and carcass traits of ducks.

Exploring the Regulatory Effect of LPJZ-658 on Copper Deficiency Combined with Sugar-Induced MASLD in Middle-Aged Mice Based on Multi-Omics Analysis

Globally, metabolic dysfunction-associated steatotic liver disease (MASLD), previously termed nonalcoholic fatty liver disease (NAFLD), is one of the most common liver disorders and is strongly associated with copper deficiency. To explore the potential effects and mechanisms of Lactiplantibacillus plantarum LPJZ-658, copper deficiency combined with a high-sugar diet-induced MASLD mouse model was utilized in this study. We fed 40-week-old (middle-aged) male C57BL/6 mice a copper-deficient and high-sugar diet for 16 weeks (CuDS), with supplementary LPJZ-658 for the last 6 weeks (CuDS + LPJZ-658). In this study, we measured body weight, liver weight, and serum biochemical markers. Lipid accumulation, histology, lipidomics, and sphingolipid metabolism-related enzyme expression were investigated to analyze liver function. Untargeted metabolomics was used to analyze the serum and the composition and abundance of intestinal flora. In addition, the correlation between differential liver lipid profiles, serum metabolites, and gut flora at the genus level was measured. The results show that LPJZ-658 significantly improves abnormal liver function and hepatic steatosis. The lipidomics analyses and metabolic pathway analysis identified sphingolipid, retinol, and glycerophospholipid metabolism as the most relevant metabolic pathways that characterized liver lipid dysregulation in the CuDS group. Consistently, RT-qPCR analyses revealed that the enzymes catalyzing sphingolipid metabolism that were significantly upregulated in the CuDS group were downregulated by the LPJZ-658 treatment. In addition, the serum metabolomics results indicated that the linoleic acid, taurine and hypotaurine, and ascorbate and aldarate metabolism pathways were associated with CuDS-induced MASLD. Notably, we found that treatment with LPJZ-658 partially reversed the changes in the differential serum metabolites. Finally, LPJZ-658 effectively regulated intestinal flora abnormalities and was significantly correlated with differential hepatic lipid species and serum metabolites. In conclusion, we elucidated the function and potential mechanisms of LPJZ-658 in alleviating copper deficiency combined with sugar-induced middle-aged MASLD and hope this will provide possible treatment strategies for improving MASLD.

Are there consistent effects of gut microbiota composition on performance, productivity and condition in poultry?

Microbiome of the gastrointestinal tract (GIT) has been identified as one of the crucial factors influencing the health and condition of domestic animals. The global poultry industry faces the challenge of understanding the complex relationship between gut microbiota composition and performance-related traits in birds. Considerable variation exists in the results of correlational studies using either 16S rRNA profiling or metagenomics to identify bacterial taxa associated with performance, productivity, or condition in poultry (e.g., body weight, growth rate, feeding efficiency, or egg yield). In this review, we survey the existing reports, discuss variation in research approaches, and identify bacterial taxa consistently linked to improved or deteriorated performance across individual poultry-focused studies. Our survey revealed high methodological heterogeneity, which was in contrast with vastly uniform focus of the research mainly on the domestic chicken (Gallus gallus) as a model. We also show that the bacterial taxa most frequently used in manipulative experiments and commercial probiotics intended for use in poultry (e.g., species of Lactobacillus, Bacillus, Enterococcus, or Bifidobacterium) do not overlap with the bacteria consistently correlated with their improved performance (Candidatus Arthromitus, Methanobrevibacter). Our conclusions urge for increased methodological standardization of the veterinary research in this field. We highlight the need to bridge the gap between correlational results and experimental applications in animal science. To better understand causality in the observed relationships, future research should involve a broader range of host species that includes both agricultural and wild models, as well as a broader range of age groups.

Dietary bile acids supplementation improves the growth performance and alleviates fatty liver in broilers fed a high-fat diet via improving the gut microbiota

This experiment aims to evaluate the effect of bile acids (BAs) in alleviating fatty liver disease induced by a high-fat diet (HFD) in broilers, and the modulation of the gut microbiota involved in this process. A total of 192 one-day-old Arbor Acres (AA) commercial male broilers were randomly divided into 4 groups and treated with the following diet: a basal-fat diet (BFD), a basal-fat diet plus bile acids (BFD + BAs), an HFD, and a high-fat diet plus bile acids (HFD + BAs). Bile acids were supplemented at the early growth stage (3-7 d), middle stage (17-21 d), and late stage (31-35 d). Results showed that BAs treatment had a significant effect on body weight on 14 d and 35 d, and increased the breast muscle weight and its index, but decreased the liver weight and abdominal fat weight on 35 d (P < 0.05). The supplementation of BAs significantly improved the serum lipid profile and decreased the level of triglycerides (TG), total cholesterol (TCHO), and nonesterified fatty acids (NEFA) on 35 d (P < 0.05). Dietary BAs supplementation significantly alleviated the hepatic TG deposition induced by HFD (P < 0.05), which was accompanied by upregulation of peroxisome proliferator-activated receptor gamma (PPARγ) and lipoprotein lipase (LPL) gene expression (P < 0.05). Moreover, the expression levels of hepatic gene adipose triglyceride lipase (ATGL), peroxisome proliferator-activated receptor α (PPARα), and apolipoprotein B (APOB) were greatly increased by BAs treatment. The analysis of 16S rRNA sequencing showed that the microbial diversity of the cecal digesta was increased by BAs in broilers with elevated abundances of Firmicutes, Lactobacillus, Anaerostipes, Sellimonas, and CHKCI002 and decreased abundances of Barnesiella and Akkermansia genus (P < 0.05). Hepatic TG content was positively correlated with the abundance of Oscillospiraceae, but it was negatively correlated with the abundance of Lactobacillus in cecal digesta (P < 0.05). These results indicate that dietary BAs can improve growth performance and alleviate fatty liver disease induced by an HFD via modulating gut microbiota in broilers.

Enzyme characterization of lactic acid bacteria isolated from duck excreta

Background and Aim

The production of lignocellulosic biomass waste in the agricultural sector of Indonesia is quite high annually. Utilization of lignocellulosic biomass waste through fermentation technology can be used as feed and biofuel. Fermentation technology requires the involvement of micro-organisms such as bacteria (lactic acid bacteria or LAB). LABs can be isolated from various sources, such as duck excreta. However, there have not been many reports of LAB from duck excreta. The present study aimed to characterize LAB enzymes isolated from duck excreta and obtain LAB enzymes with superior fermentation properties.

Materials and Methods

A total of 11 LAB cultures obtained from duck excreta in Yogyakarta, Indonesia, were tested. Enzyme characterization of each LAB was performed using the API ZYM kit (BioMérieux, Marcy-I'Etoile, France). The bacterial cell suspension was dropped onto the API ZYM™ cupule using a pipette and incubated for 4 h at 37°C. After incubation, ZYM A and ZYM B were dripped onto the API ZYM cupule, and color changes were observed for approximately 10 s under a strong light source.

Results

Esterase activity was moderate for all LABs. The activity of α-chymotrypsin, β-glucuronidase, α-fucosidase, and α-mannosidase was not observed in a total of 10 LAB. The phosphohydrolase and amino peptidase enzyme activity of seven LABs was strong. Only six LAB samples showed protease activity. The glycosyl hydrolase (GH) activity was observed in a total of 8 LAB, while the activity of 2 LAB was strong (Lactococcus lactis subsp. lactis K5 and Lactobacillus brevis M4A).

Conclusion

A total of 2 LABs have superior properties. L. lactis subsp. lactis K5 and L. brevis M4A have a high potential to be used in fermentation. They have the potential for further research, such as their effectiveness in fermentation, lignocellulose hydrolysis, feed additives, molecular characterization to detect specific enzymes, and their specific activities.

The alleviating effect of Scutellaria amoena extract on the regulation of gut microbiota and its metabolites in NASH rats by inhibiting the NLRP3/ASC/caspase-1 axis

Background: Scutellaria amoena (SA) is the root of S. amoena C.H. Wright of Labiatae, also known as Scutellaria southwestern. This is mainly distributed in Sichuan, Yunnan, and Guizhou in China. In southwest China, SA is used as an alternative method to genuine medicine for the treatment of allergy, diarrhea, inflammation, hepatitis, and bronchitis. Thus far, studies on the effects of SA on non-alcoholic steatohepatitis (NASH) are lacking. This paper investigated the effect of SA on the regulation of gut microbiota and its metabolites in NASH rats by inhibiting the NOD-like receptor 3 (NLRP3)/apoptosis-associated speck-like protein (ASC)/caspase-1 axis. Methods: A NASH rat model was induced by a high-fat diet (HFD) for 12 weeks, and rats were orally given different doses of SA extracts (150 and 300 mg/kg/d) for 6 weeks. Changes in histological parameters, body weight, organ indexes, cytokines, and biochemical parameters related to NLRP3 in NASH rats were checked. 16S rRNA gene sequencing and UPLC-MS/MS technology were used to analyze the changes in the gut microbiota composition and its metabolites in NASH rats. Results: SA significantly inhibited the HFD-induced increase in body weight, lipid levels, and inflammatory infiltration. SA notably inhibited the HFD-induced increase in the upper and lower factors of NLRP3, such as transforming growth factor (TGF)-β, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-18, pro-IL-18, IL-1β, pro-IL-1β, NLRP3, ASC, and caspase-1. Additionally, mRNA expressions of caspase-1, NLRP3, and ASC were significantly downregulated after SA treatment. The results of the intestinal flora showed that SA could increase the diversity of flora and change its structure and composition in NASH rats by reducing Firmicutes/Bacteroidetes (F/B) ratio, Blautia (genus), Lachospiraceae (family), and Christensenellaceae R-7 group (genus), and increasing Muribaculaceae (family) and Bacteroides (genus). The metabolomics revealed that 24 metabolites were possibly the key metabolites for SA to regulate the metabolic balance of NASH rats, including chenodeoxycholic acid, xanthine, and 9-OxoODE. Nine metabolic pathways were identified, including primary bile acid biosynthesis, bile secretion, purine metabolism, and secondary bile acid biosynthesis. Conclusion: SA can regulate the intestinal microbial balance and metabolic disorder by inhibiting the NLRP3/ASC/caspase-1 axis to relieve NASH.

Feeding whole-plant ensiled corn stover affects growth performance, blood parameters, and Cecal microbiota of Holdobagy goose

Introduction

The aim of this study was to investigate the effects of adding whole-plant ensiled corn stalks (WECS) to the diet of Holdorbagy geese on their growth performance, serum parameters, and cecal microbiota. Geese farming is an important agricultural practice, and optimizing their diet can contribute to better growth and health outcomes. However, there is limited research on the utilization of WECS as a feed source for geese. Understanding the potential effects of WECS on growth, blood parameters, and cecal microbiota can provide valuable insights into its feasibility and impact on geese farming practices.

Methods

A total of 144 six-week-old Holdorbagy geese were randomly assigned to one of three groups: a control group (0% WECS), a group fed 15% WECS and 85% concentrated feed (15% WECS), and a group fed 30% WECS and 70% concentrated feed (30% WECS). The trial period lasted for three weeks, during which the growth performance, serum parameters, and cecal microbiota were assessed.

Results

The results revealed significant findings in different aspects. Firstly, the feed-to-gain ratio (F/G ratio) of the 15% WECS group was significantly higher than that of the control group (p<0.05), indicating potential challenges in feed efficiency. Additionally, the average daily feed intake (ADFI) of both the 15% and 30% WECS groups was significantly higher than that of the control group (p<0.05), suggesting increased appetite or palatability of the diet containing WECS. In terms of serum parameters, the level of lactate dehydrogenase (LDH) in the 30% WECS group was significantly lower than that in the control group (p<0.05). Moreover, there was a tendency for increasing Fe levels and decreasing Zn levels with higher levels of WECS supplementation, although the differences were not statistically significant (p<0.05). Furthermore, the principal coordinate analysis showed significant differences in the composition of cecal microbiota among the three groups (p < 0.01). The observed_species, Shannon, and Pielou_e indices of the 30% WECS group were significantly higher than those of the 0% and 15% WECS groups (p<0.05), while the Simpson index of the 15% WECS group was significantly lower than that of the control group (p<0.05).

Discussion

The results indicate that the addition of WECS to the geese diet has both positive and negative effects. The study suggests that WECS can be a long-term stable feed source for geese, which can contribute to reducing feeding costs. However, it is important to monitor the amount of WECS added as it can affect the absorption of Zn by geese. Supplementation of Zn in the diet might be necessary to meet the needs of geese. Notably, adding 30% WECS to the diet can increase the richness, evenness, and diversity of the cecal microbiota, indicating potential benefits to gut health. In conclusion, this study highlights the potential of WECS as a feed source for geese. It provides valuable insights into the effects of WECS on growth performance, serum parameters, and cecal microbiota. These findings contribute to optimizing geese farming practices, improving feed utilization, and enhancing overall productivity and well-being of geese. Further research is needed to determine the optimal inclusion level of WECS and to explore strategies for mitigating any negative effects.

Association of residual feed intake with intestinal microbiome and metabolome in laying period of ducks

Introduction

Residual feed intake (RFI) is a indicator to evaluate animal feed. This experiment was explored to study the relationship between intestinal microbiome and metabolome of ducks with different residual feed intake during laying period.

Methods

A total of 300 Shaoxing ducks aged 42 weeks were randomly selected and fed a diet of 60 d. At the end of the trial, 20 samples were selected according to the phenotype of RFI and divided into two groups (HRFI and LRFI). The cecal microbiota composition was explored by 16S ribosomal RNA gene sequencing and rectal metabolomics uses liquid chromatography-mass spectrometry (LC-MS) to identify the composition of metabolites in a non-targeted manner.

Results

Results show feed intake and feed conversion ratio in the group HRFI were significantly higher than those in the group LRFI (p < 0.05). Chao1 indices were higher in the group LRFI than in the HRFI (p < 0.05), Shannon and Simpson indices were higher in the group LRFI than in the HRFI (p < 0.01). After linear discriminant analysis effect size (p < 0.05, LDA score > 3), Rikenellaceae, Rikenellaceae_RC9_gut_group, Lactobacillales and Ruminococcus_2, etc. were significantly enriched in the group LRFI at the genus level, while Prevotellaceae_NK3B31_group and Bacteria were significantly enriched in the group HRFI. After LC-MS analysis we found 338 metabolic difference products and 10 metabolic pathways, including the ABC transporter system, cysteine and methionine metabolism, arginine and proline metabolism, and vitamin B6 metabolism, were identified to be associated with the significantly differentially expressed between the groups LRFI and HRFI (p < 0.05). We hypothesize that the difference between ducks with different RFIs is mainly due to the fact that ducks with LRFI have more SCFAs-producing bacteria in their gut microorganisms, which regulate the RFI of animals. This process we found that Phascolarctobaterium and Anaerobiospirillum may provide energy for ABC transporter system by producing SCFAs, and regulate RFI to improve feed utilization efficiency.

Discussion

These results revealed the relationship between microbiome and metabonomics in laying ducks with different RFI, and provided theoretical basis for further study on the relationship between them.

Differences in meat quality between Angus cattle and Xinjiang brown cattle in association with gut microbiota and its lipid metabolism

Gut microbiota plays important roles in mediating fat metabolic events in humans and animals. However, the differences of meat quality traits related to the lipid metabolism (MQT-LM) in association with gut microbiota involving in lipid metabolism have not been well explored between Angus cattle (AG) and Xinjiang brown cattle (BC). Ten heads of 18-month-old uncastrated male AG and BC (5 in each group) raised under the identical conditions were selected to test MQT-LM, i.e., the backfat thickness (BFT), the intramuscular fat (IMF) content, the intramuscular adipocyte areas (IAA), the eye muscle area (EMA), the muscle fiber sectional area (MFSA) and the muscle shear force after sacrifice. The gut microbiota composition and structure with its metabolic function were analyzed by means of metagenomics and metabolomics with rectal feces. The correlation of MQT-LM with the gut microbiota and its metabolites was analyzed. In comparison with AG, BC had significant lower EMA, IMF content and IAA but higher BFT and MFSA. Chao1 and ACE indexes of α-diversity were lower. β-diversity between AG and BC were significantly different. The relative abundance of Bacteroidetes, Prevotella and Blautia and Prevotella copri, Blautia wexlerae, and Ruminococcus gnavus was lower. The lipid metabolism related metabolites, i.e., succinate, oxoglutaric acid, L-aspartic acid and L-glutamic acid were lower, while GABA, L-asparagine and fumaric acid were higher. IMF was positively correlated with Prevotella copri, Blautia wexlerae and Ruminococcus gnavus, and the metabolites succinate, oxoglutaric acid, L-aspartic acid and L-glutamic acid, while negatively with GABA, L-asparagine and fumaric acid. BFT was negatively correlated with Blautia wexlerae and the metabolites succinate, L-aspartic acid and L-glutamic acid, while positively with GABA, L-asparagine and fumaric acid. Prevotella Copri, Blautia wexlerae, and Ruminococcus gnavus was all positively correlated with succinate, oxoglutaric acid, while negatively with L-asparagine and fumaric acid. In conclusion, Prevotella copri, Prevotella intermedia, Blautia wexlerae, and Ruminococcus gnavus may serve as the potential differentiated bacterial species in association with MQT-LM via their metabolites of oxoglutaric acid, succinate, fumaric acid, L-aspartic acid, L-asparagine, L-glutamic acid and GABA between BC and AG.

Comparative Analyses of Production Performance, Meat Quality, and Gut Microbial Composition between Two Chinese Goose Breeds

Simple Summary

Poultry is one of the most frequently consumed meats in the world and plays an important role in the daily life of people. Goose meat is consumed by consumers because it contains a relatively high proportion of polyunsaturated fatty acids. Meat quality traits, production performance, and cecal microbiota diversity in two goose breeds (Zi goose and Xianghai flying goose) were evaluated in this study. Understanding these aspects not only provides a reference for the exploration of the relationship between the cecal microbiota and production performance but also guidelines for the human consumption of healthy poultry meat.

Abstract

Goose meat is consumed by consumers because it contains a relatively high proportion of polyunsaturated fatty acids (PUFAs). This study was conducted to explore the main differences in production performance, breast meat quality traits, and cecal microbiota compositions between the Zi goose (ZG) and Xianghai flying goose (FG). The production performance and breast meat quality trait analyses showed that compared with the ZG, the FG had a higher right breast muscle index, ileum villi height/crypt depth ratio (VH/CD), and cecum fermentation rate (higher short-chain fatty acid (SFCA) concentration); a lower abdominal fat index; a higher proportion of PUFAs; and a lower shear force. Spearman’s correlation coefficients between the cecal microbiota composition and production performance indexes suggested that the genus Faecalibacterium was positively associated with production performance; in contrast, the genus Candidatus Saccharimonas was negatively correlated with production performance; moreover, the Ruminococcus torques group, Parasutterella, and Methanobrevibacter were negatively related to the VH/CD. Taken together, in this particular trial, FG had better production performance, healthier meat quality traits, and better intestinal digestion and absorption capacities than ZG. These results not only provide a useful data reference for the production of healthy geese for human consumption but can also help guide the utilization of goose breed resources.

Reproductive Hormones Mediate Intestinal Microbiota Shifts during Estrus Synchronization in Grazing Simmental Cows

To study shifts in the intestinal microbiota during estrus synchronization in ruminants, we characterized the intestinal microbiota in grazing Simmental cows and the possible mechanism that mediates this shift. Fourteen postpartum Simmental beef cows were synchronized beginning on day 0 (D0) with a controlled internal release device (CIDR), and cloprostenol was injected on D9 when the CIDR was withdrawn. Synchronization ended with timed artificial insemination on D12. Serum and rectal samples harvested on D0, D9, and D12 were analyzed to assess the reproductive hormones and microbiota. Reproductive hormones in the serum of the host were measured using enzyme-linked immunosorbent assay. The microbiota was characterized using 16S rRNA sequencing of the V3−V4 hypervariable region, alpha diversity and beta diversity analyses (principal coordinate analysis, PCoA), cladogram of the linear discriminant analysis effect size (LEfSe) analysis, and microbiota function analysis. Levels of the reproductive hormones, except gonadotropin-releasing hormone (p > 0.05), shifted among D0, D9, and D12 (p < 0.05). Decreased community diversity (Chao1 and ACE) was observed on D12 compared with D0 (p < 0.05). The beta diversity (PCoA) of the microbiota shifted markedly among D0, D9, and D12 (p < 0.05). The LEfSe analysis revealed shifts in the intestinal microbiota communities among D0, D9, and D12 (p < 0.05 and LDA cutoff >3.0). The KEGG pathway analysis showed that carbohydrate metabolism, genetic information and processing, the excretory system, cellular processes and signaling, immune system diseases, and the metabolism were altered (p < 0.05). Reproductive hormones (especially estradiol) were correlated with the alpha diversity indices, beta diversity indices, and an abundance of biomarkers of the shifting intestinal microbiota (p < 0.05). In conclusion, the structure, composition, and function of the intestinal microbiota were shifted during estrus synchronization in a grazing Simmental cow model, and these shifts were mediated by reproductive hormones.

Dietary γ-Aminobutyric Acid Supplementation Inhibits High-Fat Diet-Induced Hepatic Steatosis via Modulating Gut Microbiota in Broilers

The present study aims to investigate the effect of γ-aminobutyric acid (GABA) on liver lipid metabolism and on AA broilers. Broilers were divided into three groups and fed with low-fat diets, high-fat diets, and high-fat diets supplemented with GABA. Results showed that GABA supplementation decreased the level of triglyceride (TG) in the serum and liver of broilers fed high-fat diets, accompanied by up-regulated mRNA expression of genes related to lipolysis and β-oxidation in the liver (p < 0.05). Furthermore, GABA supplementation increased liver antioxidant capacity, accompanied by up-regulated mRNA expression of antioxidant genes (p < 0.05). 16S rRNA gene sequencing showed that GABA improved high-fat diet-induced dysbiosis of gut microbiota, increased the relative abundance of Bacteroidetes phylum and Barnesiella genus, and decreased the relative abundance of Firmicutes phylum and Ruminococcus_torques_group and Romboutsia genus (p < 0.05). Moreover, GABA supplementation promoted the production of propionic acid and butyric acid in cecal contents. Correlation analysis further suggested the ratio of Firmicutes/Bacteroidetes negatively correlated with hepatic TG content, and positively correlated with cecal short chain fatty acids content (r > 0.6, p < 0.01). Together, these data suggest that GABA supplementation can inhibit hepatic TG deposition and steatosis via regulating gut microbiota in broilers.

The Role of Gut Microbiota in the Skeletal Muscle Development and Fat Deposition in Pigs

Pork quality is a factor increasingly considered in consumer preferences for pork. The formation mechanisms determining meat quality are complicated, including endogenous and exogenous factors. Despite a lot of research on meat quality, unexpected variation in meat quality is still a major problem in the meat industry. Currently, gut microbiota and their metabolites have attracted increased attention in the animal breeding industry, and recent research demonstrated their significance in muscle fiber development and fat deposition. The purpose of this paper is to summarize the research on the effects of gut microbiota on pig muscle and fat deposition. The factors affecting gut microbiota composition will also be discussed, including host genetics, dietary composition, antibiotics, prebiotics, and probiotics. We provide an overall understanding of the relationship between gut microbiota and meat quality in pigs, and how manipulation of gut microbiota may contribute to increasing pork quality for human consumption.

Effect of Lotus Seed Resistant Starch on Lactic Acid Conversion to Butyric Acid Fermented by Rat Fecal Microbiota

The aim was to investigate the effect of lotus seed resistant starch (LRS) on lactic acid (LA) conversion to butyric acid (BA) fermented by rat fecal microbiota to construct an acetyl CoA pathway. According to growth curves, the microbiota compositions at 10 and 36 h were further analyzed. The microbiota in the LRS group had higher richness and diversity compared to glucose (GLU) and high amylose maize starch (HAMS). Moreover, LRS and isotope LA promoted the growth of Lactobacillus and Bifidobacterium, promoted BA production, and inhibited the growth of Escherichia-Shigella. The BUT pathway played a dominant role in three groups. At 10 h, Escherichia-Shigella and Bifidobacterium showed a negative correlation with BUT and a positive correlation with BUK, whereas Escherichia-Shigella, Allobaculum, Bifidobacterium, and Ralstonia showed a positive correlation with BUT and BUK at 36 h. [3-¹³C] LA was converted to [4-¹³C] BA by the isotope labeling technique. Finally, LRS promoted LA conversion to BA mainly by the BUT pathway in intestinal microbiota, especially including Allobaculum, Bifidobacterium, and Ralstonia.

Effect of feed restriction on the intestinal microbial community structure of growing ducks

In poultry, feed restriction is common feeding management to limit poultry nutrients intake so that poultry only intake the essential energy, meeting the basic need of growth and development. Our study investigated whether feeding restriction affects the diversity of the intestinal microbiota of growing breeding ducks. In this research, the 60-120-day-old ducks were raised in restricted and free-feeding groups. After slaughtering, the carcass traits and the cecal contents were collected for 16S rRNA sequencing analysis. After feeding restriction, the growth rate of ducks was limited, the weight and rate of abdominal fat decreased, and the rate of chest and leg muscles increased. In addition, feeding restriction can also change the diversity of intestinal microorganisms in breeding ducks, such as the increase of Firmicutes abundance and the decrease of Bacteroidetes abundance. After analyzing of correlation, significant correlations between gut microbiota and carcass phenotypes were found. The results indicated that gut microbiota might be involved in the life activities associated with phenotypic changes. This study proved the effect of feeding methods on the intestinal microbiota of ducks, providing a theoretical basis of the microbial angle for raising ducks in a feeding-restricted period.

The Spatial and Temporal Characterization of Gut Microbiota in Broilers

The gut microbiota of chickens plays an important role in host physiology. However, the colonization and prevalence of gut microbiota have not been well-characterized. Here, we performed 16S rRNA gene sequencing on the duodenal, cecal and fecal microbiota of broilers at 1, 7, 21, and 35 days of age and characterized the dynamic succession of microbiota across the intestinal tract. Our results showed that Firmicutes was the most abundant phylum detected in each gut site at various ages, while the microbial diversity and composition varied among the duodenum, cecum, and feces at different ages. The microbial diversity and complexity of the cecal microbiota increased with age, gradually achieving stability at 21 days of age. As a specific genus in the cecum, Clostridium_sensu_stricto_1 accounted for 83.50% of the total abundance at 1 day of age, but its relative abundance diminished with age. Regarding the feces, the highest alpha diversity was observed at 1 day of age, significantly separated from the alpha diversity of other ages. In addition, no significant differences were observed in the alpha diversity of duodenal samples among 7, 21, and 35 days of age. The predominant bacterium, Lactobacillus, was relatively low (0.68–6.04%) in the intestinal tract of 1-day-old chicks, whereas its abundance increased substantially at 7 days of age and was higher in the duodenum and feces. Escherichia-Shigella, another predominant bacterium in the chicken intestinal tract, was also found to be highly abundant in fecal samples, and the age-associated dynamic trend coincided with that of Lactobacillus. In addition, several genera, including Blautia, Ruminiclostridium_5, Ruminococcaceae_UCG-014, and [Ruminococcus]_torques_group, which are related to the production of short-chain fatty acids, were identified as biomarker bacteria of the cecum after 21 days of age. These findings shed direct light on the temporal and spatial dynamics of intestinal microbiota and provide new opportunities for the improvement of poultry health and production.

Modulation of the Intestinal Microbiota by the Early Intervention with Clostridium Butyricum in Muscovy Ducks

This study evaluated the effects of early intervention with Clostridium butyricum (C. butyricum) on shaping the intestinal microbiota of Muscovy ducklings. A total of 160 1-day-old male ducks were randomly divided into two groups: the CB group was administered with 1 mL of C. butyricum (2 × 10⁹ CFU/mL), while the C group was given 1 mL of saline. The administration lasted for 3 days. We found that C. butyricum had no significant effect on growth performance. The results indicated that inoculation with C. butyricum could significantly increase the abundance of genera Bacteroides, Lachnospiraceae_uncultured, and Ruminococcaceae on Day 14 and reduce the abundance of Escherichia–Shigella and Klebsiella on Days 1 and 3. Moreover, the CB group ducks had higher concentrations of acetic, propionic, and butyrate in the cecum than the C group. Overall, these results suggest that early intervention with C. butyricum could have positive effects on Muscovy ducks’ intestinal health, which might be attributed to the modulation in the intestinal microbial composition and the increased concentrations of short-chain fatty acids (SCFAs). C. butyricum might even have the potential to help the colonization of beneficial bacteria in the intestine microbiota in Muscovy ducks in poultry and other livestock.

Molecular characterization, developmental expression, and modulation of occludin by early intervention with Clostridium butyricum in Muscovy ducks

Occludin is an important component of tight junction proteins and has been extensively studied in animals such as mice, chickens, geese, and pigs. As one of the most important waterfowl species in China, Muscovy duck (Cairina moschata) is an important economic animal for meat. However, research on the occludin gene in Muscovy duck is lacking. In the present study, Muscovy duck occludin cDNA was cloned for the first time. The length of the cDNA was 1,699 bp, and it showed a high sequence similarity with the Anser cygnoides domesticus and Gallus gallus occludin genes. The occludin gene was differentially expressed in the tissues of healthy ducks. The highest and lowest expressions of occludin were observed in the crop and the spleen, respectively. After the oral administration of Clostridium butyricum (CB), the occludin expression in the ileum of 7-day-old Muscovy ducks was significantly upregulated and subsequently showed a decreasing trend in 14-day-old Muscovy ducks. Under the early intervention of CB, no significant difference was observed in the occludin expression of cecum between the control and CB group. Collectively, these results suggest that CB plays an important role in regulating the expression of the occludin gene in Muscovy ducks, and adding CB in feed may maintain the intestinal barrier of ducks by regulating the expression of occludin.