Multi‑omics analysis reveals gut microbiota‑ovary axis contributed to the follicular development difference between Meishan and Landrace×Yorkshire sows

Background The mechanism by which Meishan(MS)sows are superior to white crossbred sows in ovarian follicle development remains unclear.Given gut microbiota could regulate female ovarian function and reproductive capacity,this study aimed to determine the role of gut microbiota-ovary axis on follicular development in sows.Methods We compared the ovarian follicular development,gut microbiota,plasma metabolome,and follicular fluid metabolome between MS and Landrace×Yorkshire(L×Y)sows.A H_(2)O_(2)-induced cell apoptosis model was used to evaluate the effects of multi-omics identified metabolites on the apoptosis of porcine ovarian granulosa cells in vitro.Results Compared with L×Y sows,MS sows have greater ovary weight and improved follicular development,including the greater counts of large follicles of diameter≥5 mm,secondary follicles,and antral follicles,but lesser atretic follicles.The ovarian granulosa cells in MS sows had alleviated apoptosis,which was indicated by the increased BCL-2,decreased caspases-3,and decreased cleaved caspases-3 than in L×Y sows.The ovarian follicular fluid of MS sows had higher concentrations of estradiol,progesterone,follicle-stimulating hormone,luteinizing hormone,and insulin like growth factor 1 than L×Y sows.Gut microbiota of MS sows formed a distinct cluster and had improved alpha diversity,including increased Shannon and decreased Simpson than those of L×Y sows.Corresponding to the enhanced function of carbohydrate metabolism and elevated short-chain fatty acids(SCFAs)in feces,the differential metabolites in plasma between MS and L×Y sows are also mainly enriched in pathways of fatty acid metabolism.There were significant correlations among SCFAs with follicular development,ovarian granulosa cells apoptosis,and follicular fluid hormones,respectively.Noteworthily,compared with L×Y sows,MS sows had higher follicular fluid SCFAs concentrations which could ameliorate H_(2)O_(2)-induced porcine granulosa cells apoptosis in vitro.Conclusion MS sows have more secondary and antral follicles,but fewer atretic follicles and apoptotic ovarian granulosa cells,as well as harbored a distinctive gut microbiota than L×Y sows.Gut microbiota may participate in regulating ovarian follicular development via SCFAs affecting granulosa cells apoptosis in sows.

Gut microbiota contributes to the development of endometrial glands in gilts during the ovary-dependent period

Background:The hyper-prolificacy Meishan gilts achieved a superior endometrial gland development(EGD)than white crossbred gilts during the ovary-independent period(before 60 d of age).Then,the EGD continues under the management of ovary-derived steroid hormones that regulated by gut microbiota(after 60 d of age).However,whether Meishan gilts’superiority in EGD lasting to the ovary-dependent period(after 60 d of age)and the role of gut microbiota in this period both remain unclear.Methods:Meishan gilts and Landrace x Yorkshire(LxY)gilts were raised under the same housing and feeding conditions until sexual maturity and then we compared their EGD and gut microbiota.Meanwhile,we transplanted fecal microbiota from Meishan gilts to L×Y gilts to explore the role of gut microbiota in EGD.We sampled plasma every 3 weeks and collected the uterus,ovary,liver,and rectal feces after the sacrifice.We then determined the hormone concentrations and expressions of the EGD-related genes.We also profiled the gut microbiota using 16S rDNA sequencing and metabolites of plasma and liver tissue using untargeted metabolomics.Finally,the correlation analysis and significant test was conducted between FMT-shifted gut microbes and EGD-related indices.Results:Meishan gilts have larger endometrial gland area(P<0.001),longer uterine horn length(P<0.01)but lighter uterine horn weight(P<0.05),a distinctive gut microbiota compared with L×Y gilts.Fecal microbiota transplantation(FMT)increased endometrial gland area(P<0.01).FMT markedly shifted the metabolite profiles of both liver and plasma,and these differential metabolites enriched in steroid hormone biosynthesis pathway.FMT increased estradiol and insulin-like growth factor 1 but decreased progesterone dynamically.FMT also increased the expression of the EGD-related genes estrogen receptor 1 gene,epithelial cadherin,and forkhead box protein A2.There is a significant correlation between FMT-shifted gut microbes and EGD-related indices.Conclusion:Sexually matured Meishan gilts achieved a superior EGD than LxY gilts.Meanwhile,gut microbiota contribute to the EGD potentially via regulating of steroid hormones during the ovary-dependent period.

Dietary ellagic acid supplementation attenuates intestinal damage and oxidative stress by regulating gut microbiota in weanling piglets

Intestinal oxidative stress triggers gut microbiota dysbiosis,which is involved in the etiology of postweaning diarrhea and enteric infections.Ellagic acid(EA)can potentially serve as an antioxidant supplement to facilitate weaning transition by improving intestinal oxidative stress and gut microbiota dysbiosis.Therefore,we aimed to investigate the effects of dietary EA supplementation on the attenuation of intestinal damage,oxidative stress,and dysbiosis of gut microbiota in weanling piglets.A total of126 piglets were randomly assigned into 3 groups and treated with a basal diet and 2 m L saline orally(Ctrl group),or the basal diet supplemented with 0.1%EA and 2 m L saline orally(EA group),or the basal diet and 2 m L fecal microbiota suspension from the EA group orally(FEA group),respectively,for 14 d.Compared with the Ctrl group,EA group improved growth performance by increasing average daily feed intake and average daily weight gain(P<0.05)and decreasing fecal scores(P<0.05).EA group also alleviated intestinal damage by increasing the tight junction protein occludin(P<0.05),villus height,and villus height-to-crypt depth ratio(P<0.05),while decreasing intestinal epithelial apoptosis(P<0.05).Additionally,EA group enhanced the jejunum antioxidant capacity by increasing the total antioxidant capacity(P<0.01),catalase(P<0.05),and glutathione/oxidized glutathione(P<0.05),but decreased the oxidative metabolite malondialdehyde(P<0.05)compared to the Ctrl group.Compared with the Ctrl group,EA and FEA groups increased alpha diversity(P<0.05),enriched beneficial bacteria(Ruminococcaceae and Clostridium ramosum),and increased metabolites short-chain fatty acids(P<0.05).Correspondingly,FEA group gained effects comparable to those of EA group on growth performance,intestinal damage,and intestinal antioxidant capacity.In addition,the relative abundance of bacteria shifted in EA and FEA groups was significantly related to the examined indices(P<0.05).Overall,dietary EA supplementation could improve growth performance and attenuate intestinal damage and oxidative stress by regulating the gut microbiota in weanling piglets.

Rice bran oil supplementation protects swine weanlings against diarrhea and lipopolysaccharide challenge

Early weaned piglets suffer from oxidative stress and enteral infection,which usually results in gut microbial dysbiosis,serve diarrhea,and even death.Rice bran oil(RBO),a polyphenol-enriched by-product of rice processing,has been shown to have antioxidant and anti-inflammatory properties both in vivo and in vitro.Here,we ascertained the proper RBO supplementation level,and subsequently determined its effects on lipopolysaccharide(LPS)-induced intestinal dysfunction in weaned piglets.A total of 168 piglets were randomly allocated into four groups of seven replicates(42 piglets each group,(21±1)d of age,body weight(7.60±0.04)kg,and half males and half females)and were given basal diet(Ctrl)or basal diet supplemented with 0.01%(mass fraction)RBO(RBO1),0.02%RBO(RBO2),or 0.03%RBO(RBO3)for 21 d.Then,seven piglets from the Ctrl and the RBO were treated with LPS(100μg/kg body weight(BW))as LPS group and RBO+LPS group,respectively.Meanwhile,seven piglets from the Ctrl were treated with the saline vehicle(Ctrl group).Four hours later,all treated piglets were sacrificed for taking samples of plasma,jejunum tissues,and feces.The results showed that 0.02%was the optimal dose of dietary RBO supplementation based on diarrhea,average daily gain,and average daily feed intake indices in early weaning piglets.Furthermore,RBO protected piglets against LPS-induced jejunal epithelium damage,which was indicated by the increases in villus height,villus height/crypt depth ratio,and Claudin-1 levels,as well as a decreased level of jejunal epithelium apoptosis.RBO also improved the antioxidant ability of LPS-challenged piglets,which was indicated by the elevated concentrations of catalase and superoxide dismutase,and increased total antioxidant capacity,as well as the decreased concentrations of diamine oxidase and malondialdehyde in plasma.Meanwhile,RBO improved the immune function of LPS-challenged weaned piglets,which was indicated by elevated immunoglobulin A(IgA),IgM,β-defensin-1,and lysozyme levels in the plasma.In addition,RBO supplementation improved the LPS challenge-induced dysbiosis of gut microbiota.Particularly,the indices of antioxidant capacity,intestinal damage,and immunity were significantly associated with the RBO-regulated gut microbiota.These findings suggested that 0.02%RBO is a suitable dose to protect against LPS-induced intestinal damage,oxidative stress,and jejunal microbiota dysbiosis in early weaned piglets.

Identification of gut microbes associated with feed efficiency by daily-phase feeding strategy in growing-finishing pigs

Feed efficiency is one of the most important issues for sustainable pig production.Daily-phase feeding(DPF)is a form of precision feeding that could improve feed efficiency in pigs.Gut microbiota can regulate host nutrient digestion,absorption,and metabolism.However,which key microbes may play a vital role in improving the feed efficiency during DPF remains unclear.In the present study,we used a DPF program compared to a three-phase feeding(TPF)program in growing-finishing pigs to investigate the effects of gut microbiota on feed efficiency.A total of 204 Landrace×Yorkshire pigs(75 d)were randomly assigned into 2 treatments.Each treatment was replicated 8 times with 13 to 15 pigs per replicate pen.Pigs in the TPF group were fed with a commercial feeding program that supplied fixed feed for phasesⅠ,Ⅱ,andⅢ,starting at 81,101,and 132 d of age,respectively,and pigs in the DPF group were fed a blend of adjacent phase feed from 81 to 155 d at a gradual daily ratio and phaseⅢfeed from 155 to 180 d of age.Daily feed intake and body weight were recorded by a computerized device in the feeders.Feces and blood samples were collected from 1 pig per replicate at 155 and 180 d of age.The results showed that the DPF program remarkably improved the feed efficiency at 155 d(P<0.001)and 180 d of age(P<0.001),with a significant reduction of the intake of crude protein(P<0.01),net energy(P<0.001),crude fiber(P<0.001),ether extract(P<0.01),and ash(P<0.001).The daily-phase feeding program increased the abundance of Prevotella copri(P<0.05)and Paraprevotella clara(P<0.05),while it decreased the abundance of Ocilibacter(P<0.05)at 155 d of age.The results of correlation analysis indicated that the differentially abundant microbiota communities were closely associated with 20 metabolites which enriched amino acid and phenylalanine metabolism.Our results suggest that 2 key microbes may contribute to feed efficiency during daily-phase feeding strategies in pigs.

Obese Ningxiang pig-derived microbiota rewires carnitine metabolism to promote muscle fatty acid deposition in lean DLY pigs

The gut microbiota consistently shows strong correlations with lipid metabolism in humans and animals,and whether the gut microbiota contributes to muscle fatty acid(FA)deposition and meat traits in farm animals has not been fully resolved.In this study,we aimed to unveil the microbial mechanisms underlying muscle FA deposition in pigs.First,we systematically revealed the correlation between the gut microbiome and muscle FA levels in 43 obese Ningxiang pigs and 50 lean Duroc Landrace Yorkshire(DLY)pigs.Mutual fecal microbial transplantation showed that the obese Ningxiang pig-derived microbiota increased the muscle FA content and improved meat quality by reshaping the gut microbial composition in lean DLY pigs.Lactobacillus reuteri has been identified as a potential microbial biomarker in obese Ningxiang pig-derived microbiota-challenged DLY pigs.A gavage experiment using lean DLY pigs confirmed that L.reuteri XL0930 isolated from obese Ningxiang pigs was the causal species that increased the muscle FA content.Mechanistically,SLC22A5,a carnitine transporter,was downregulated in L.reuteri XL0930-fed DLY pigs,resulting in reduced muscle carnitine levels.Muscle and intestinal L-carnitine levels,which correlated with the muscle FA content,impeded fat synthesis and FA accumulation in in vitro and in vivo models.In conclusion,we uncovered an unexpected and important role of the obese Ningxiang pig-derived microbiota in regulating muscle FA metabolism via the SLC22A5-mediated carnitine system.

Multi-omics analysis reveals gut microbiota-induced intramuscular fatdeposition via regulating expression of lipogenesis-associated genes

The gut microbiome has great effects on the digestion, absorption, and metabolism of lipids. However,the microbiota composition that can alter the fat deposition and the meat quality of pigs remains unclear.Here, we used Laiwu (LW) pigs (a native Chinese breed with higher intramuscular fat) compared withcommercial crossbreed Duroc×(Landrace×Yorkshire) (DLY) pigs to investigate the effects of microbiotaon meat quality, especially in intramuscular fat content. A total of 32 DLY piglets were randomly allottedto 4 groups and transplanted with fecal microbiota from healthy LW pigs. The results indicated that thehigh dose of fecal microbiota transplantation (HFMT) selectively enhanced fat deposition in longissimusdorsi (P < 0.05) but decreased backfat thickness (P < 0.05) compared with control group. HFMT significantlyaltered meat color and increased feed conversation ratio (P < 0.05). Furthermore, the multi-omicsanalysis revealed that Bacteroides uniformis, Sphaerochaeta globosa, Hydrogenoanaerobacterium saccharovorans,and Pyramidobacter piscolens are the core species which can regulate lipid deposition. A total of140 male SPF C57BL/6j mice were randomly allotted into 7 groups and administrated with these 4 microbesalone or consortium to validate the relationships between microbiota and lipid deposition.Inoculating the bacterial consortium into mice increased intramuscular fat content (P < 0.05) comparedwith control mice. Increased expressions of lipogenesis-associated genes including cluster of differentiation36 (Cd36), diacylglycerol O-acyltransferase 2 (Dgat2), and fatty acid synthase (FASN) wereobserved in skeletal muscle in the mice with mixed bacteria compared with control mice. Together, ourresults suggest that the gut microbiota may play an important role in regulating the lipid deposition in the muscle of pigs and mice.

Integrated analysis of multi-tissues lipidome and gut microbiome reveals microbiota-induced shifts on lipid metabolism in pigs

Lipid metabolism is very important for meat quality in pigs.Accumulating evidence shows that gut microbiota can contribute to this physiological process.However,the gut microbiota that function in lipid metabolism and adipogenesis remains unclear.Here,we compared the characteristics of fat deposition and gut microbial community between Laiwu pigs and Duroc(LandraceYorkshire)(DLY)pigs.Fecal microbiota transplantation(FMT)was performed to determine the possible impact of gut microbiota on lipid metabolism in pigs.An integrated analysis of the gut microbiome and lipidome of the small intestine,plasma,and liver was conducted to investigate the effects of FMT on host lipid metabolism.The comparative analysis of the gut microbiome showed higher abundance of Bacteroidetes(P=0.0018)while lower abundance of Firmicutes(P=0.012)in Laiwu pigs,and the microbial composition can be transferred from Laiwu pigs into DLY pigs.Transmission electron microscope and Oil red-O staining were performed to analyze the effects of FMT on lipid deposition in liver,the main target organ for lipid metabolism.The results showed that FMT significantly increased the number of lipid droplets(P=0.0035)and lipid accumulation(P=0.0026)in liver.Furthermore,integrated multi-tissues lipidome analysis demonstrated that the fatty acyls and glycerophospholipids were significantly increased(P<0.01)in intestine and liver,while glycerolipids and fatty acyls were reduced(P<0.01)in plasma.In the small intestine,FMT increased(P<0.01)the relative abundance of polyketides and prenol lipids but reduced(P<0.01)the saccharolipids.Correlation analysis revealed the potential interactions between microbiota and lipid metabolites.Together,our results indicated that the gut microbiota may regulate the lipid metabolism and enhance the accumulation of lipid droplets in the liver of pigs.