摘要：
Contamination with fumonisin B1 (FB1) represents a global health problem. FB1 exposure may also trigger intestinal injury by activating inflammatory responses, leading to a reduction in production performance and economic benefits. However, the mechanism of FB1-induced intestinal inflammatory injury is still unclear. At the same time, it is urgent to develop antibiotic alternatives and therapeutic targets to alleviate antibiotic resistance and to ensure effective treatment of intestinal inflammatory injury. We combined network pharmacology and in vitro experiments to explore the core therapeutic targets and potential mechanism of luteolin in FB1-induced intestinal inflammatory injury. Network pharmacology and molecular docking revealed that nuclear factor kappa B (NF-kappa B) p65, extracellular signal-regulated kinase (ERK), interleukin 6 (IL-6) and IL-1 beta are the important targets, and the NF-kappa B and ERK signalling pathways are critical in FB1-induced intestinal inflammatory injury. Besides, in vitro experiments further demonstrated that luteolin can inhibit FB1-induced intestinal inflammatory injury by inhibiting activation of the NF-kappa B and ERK signalling pathways and reducing the expression of IL-6 and IL-1 beta in IPEC-J2 cells. We have comprehensively illustrated the potential targets and molecular mechanism by which luteolin can alleviate FB1-induced intestinal inflammatory injury. Luteolin may be an effective antibiotic alternative to prevent intestinal inflammatory injury.
摘要：
Protein homeostasis is essential for cyanobacteria to maintain proper cellular function under adverse and fluctuating conditions. The AAA+ superfamily of proteolytic complexes in cyanobacteria plays a critical role in this process, including ClpXP, which comprises a hexameric ATPase ClpX and a tetradecameric peptidase ClpP. Despite the physiological effects of ClpX on growth and photosynthesis, its potential substrates and underlying mechanisms in cyanobacteria remain unknown. In this study, we employed a streptavidin-biotin affinity pull-down assay coupled with label-free proteome quantitation to analyze the interactome of ClpX in the model cyanobacterium Synechocystis sp. PCC 6803 (hereafter Synechocystis). We identified 503 proteins as potential ClpX-binding targets, many of which had novel interactions. These ClpX-binding targets were found to be involved in various biological processes, with particular enrichment in metabolic processes and photosynthesis. Using protein-protein docking, GST pull-down, and biolayer interferometry assays, we confirmed the direct association of ClpX with the photosynthetic proteins, ferredoxin-NADP(+) oxidoreductase (FNR) and phycocyanin subunit (CpcA). Subsequent functional investigations revealed that ClpX participates in the maintenance of FNR homeostasis and functionality in Synechocystis grown under different light conditions. Overall, our study provides a comprehensive understanding of the extensive functions regulated by ClpX in cyanobacteria to maintain protein homeostasis and adapt to environmental challenges.
作者机构：
[Zhixu Wu] Hangzhou Bureau of Ecology and Environment Chun’an Branch, Hangzhou 311700, China;These authors contributed equally to this work.;Zhejiang Provincial Key Laboratory for Subtropical Water Environment and Marine Biological Resources Protection, Wenzhou University, Wenzhou 325035, China;National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou University, Wenzhou 325035, China;Authors to whom correspondence should be addressed.
通讯机构：
[Renhui Li; Fangfang Cai] A;Authors to whom correspondence should be addressed.<&wdkj&>Zhejiang Provincial Key Laboratory for Subtropical Water Environment and Marine Biological Resources Protection, Wenzhou University, Wenzhou 325035, China<&wdkj&>National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou University, Wenzhou 325035, China<&wdkj&>Authors to whom correspondence should be addressed.<&wdkj&>Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan 430023, China
关键词：
new species;16S rRNA gene;16S–23S ITS;polyphasic approach
摘要：
During the study of diversity in filamentous cyanobacteria in China, two strains (WZU0719 and WZU0723) with the form of thin filaments were isolated from the surface of Qiandao Lake, a large freshwater lake in Zhejiang Province, China. A comprehensive analysis was conducted, incorporating morphological, ecological, and molecular data. The morphological examination provided an initial identification as a Leptolyngbya-like cyanobacterium. Genetic characterization was also performed by amplifying the 16S rRNA gene and the 16S-23S rRNA internal transcribed spacer (ITS) region. The phylogenetic grouping based on the 16S rRNA gene demonstrates that the examined strain is unequivocally assigned to the Pegethrix genus. However, it possesses distinct phylogenetic divergence from the six described Pegethrix species. Additionally, discrepancies in habitat further differentiate it from other members of this genus. Employing the polyphasic approach, we present a comprehensive account of the newly discovered taxa: Pegethrix qiandaoensis sp. nov. The novel taxonomic finding in this research significantly contributes to enhancing the comprehension of Pegethrix diversity across various habitats.
关键词：
Baicalin;Glaesserella parasuis;Liquid chromatography–tandem mass spectrometry;Myosin light chain kinase-myosin light chain;P2Y6;Pannexin 1;Phospholipase C-Protein kinase C
摘要：
Glaesserella parasuis can induce endothelial barrier damage in piglets, although the mechanism by which this pathogen triggers inflammatory damage remains unclear. Baicalin possesses anti-inflammatory and anti-oxidant activities. However, whether baicalin can relieve endothelial barrier damage caused by Glaesserella parasuis infection has not yet been studied. Hence, we evaluated the ability of baicalin to counteract the changes induced by Glaesserella parasuis in porcine aortic vascular endothelial cells. The results showed that Glaesserella parasuis could upregulate the expression of pannexin 1 channel protein and promote the release of adenosine triphosphate, adenosine diphosphate, adenosine 3'-monophosphate, uridine triphosphate, uridine diphosphate, and uridine monophosphate in porcine aortic vascular endothelial cells. The expression level of purinergic receptor P2Y6 was upregulated in porcine aortic vascular endothelial cells triggered by Glaesserella parasuis. In addition, Glaesserella parasuis could activate phospholipase C-protein kinase C and myosin light chain kinase-myosin light chain signaling pathways in porcine aortic vascular endothelial cells. Baicalin could inhibit pannexin 1 channel protein expression, reduce adenosine triphosphate, adenosine diphosphate, adenosine 3'-monophosphate, uridine triphosphate, uridine diphosphate, and uridine monophosphate release, and attenuate the expression level of P2Y6 in porcine aortic vascular endothelial cells induced by Glaesserella parasuis. Baicalin could also reduce the activation of phospholipase C-protein kinase C and myosin light chain kinase-myosin light chain signaling pathways in porcine aortic vascular endothelial cells triggered by Glaesserella parasuis. Our study report that Glaesserella parasuis could promote pannexin 1 channel protein expression, induce nucleosides substance release, and P2Y6 expression in porcine aortic vascular endothelial cells and baicalin could inhibit the expression levels of pannexin 1, nucleosides substance, and P2Y6 in the porcine aortic vascular endothelial cells induced by Glaesserella parasuis, which might be served as some targets for treatment of inflammation disease caused by Glaesserella parasuis.
摘要：
The effects of monolaurin (ML) on the health of piglets infected with porcine epidemic diarrhoea virus (PEDV) have not been fully understood. This study aimed to investigate its role in blood biochemical profile, intestinal barrier function, antioxidant function and the expression of antiviral genes in piglets infected with PEDV. Thirty-two piglets were randomly divided into four groups: control group, ML group, PEDV group and ML + PEDV group. Piglets were orally administrated with ML at a dose of 100 mg/kg·BW for 7 d before PEDV infection. Results showed that PEDV infection significantly decreased D-xylose content and increased intestinal fatty acid-binding protein content, indicating that PEDV infection destroyed intestinal barrier and absorption function. While it could be repaired by ML administration. Moreover, ML administration significantly decreased plasma blood urea nitrogen and total protein content upon PEDV infection. These results suggested ML may increase protein utilisation efficiency. ML administration significantly decreased the number of large unstained cells and Hb and increased the number of leucocytes and eosinophils in the blood of PEDV-infected piglets, indicating ML could improve the immune defense function of the body. In the presence of PEDV infection, ML administration significantly increased superoxide dismutase and catalase activities in blood and colon, respectively, indicating ML could improve antioxidant capacity. Besides, ML administration reversed the expression of ISG15, IFIT3 and IL-29 throughout the small intestine and Mx1 in jejunum and ileum, indicating the body was in recovery from PEDV infection. This study suggests that ML could be used as a kind of feed additive to promote swine health upon PEDV infection.
摘要：
The embryonic loss during early stage of gestation is one of the major causes of infertility for domestic ruminants, causing huge economic losses to pasture. Maternal recognition of pregnancy and implantation are the crucial process for determining the successful establishment and development of pregnancy in cattle. The research on molecular mechanisms of pregnancy recognition will facilitate illustrating the complex process of pregnancy establishment and help to improve pregnancy outcomes. In this study, we performed transcriptomic analysis of primary bovine endometrial epithelial cells (BEND) with or without IFNT and hormones intervention through RNA sequencing. We eventually identified 608 differentially expressed genes (DEGs) including 409 up-regulated genes and 199 down-regulated genes in IFNT and hormones-treated group compared with control group. Gene Ontology (GO) enrichment analysis demonstrated that the majority of DEGs were implicated in immune system process, response to external stimulus, response to cytokine, regulation of response to stress. Results from KEGG analysis showed a significant enrichment of NOD-like receptor signaling pathway, antigen processing and presentation, necroptosis, oxidative phosphorylation, RIG-I-like receptor signaling pathway. Additionally, a set of promising candidate genes, including (USP18, STAT1, PSMB8, IFIH1, MX2, IFI44, DHX58, CASP8, DRAM1, CXCR4), were characterized by constructing an integrated interaction network. Specifically, the mRNA expression of HOXA11, PTGS1 and PTGS2 were remarkably suppressed by silencing DRAM1 under IFNT and hormone administration, thus speculating that DRAM1 might play a crucial role in early pregnancy by regulating endometrial function. The results of this study depicted a relatively comprehensive transcriptional profiles of BEND in response to IFNT and hormones, which contributes to a better understanding of gene interaction network and underlying regulatory mechanisms in endometrium of ruminants during early pregnancy.
期刊：
Science of The Total Environment,2024年922:171015 ISSN：0048-9697
通讯作者：
Zhao, Yi;Li, Jin-Long
作者机构：
[Dai, Xue-Yan; Guo, Jian-Ying; Lin, Jia; Saleem, Muhammad Asmat Ullah; Zhao, Yi; Zhu, Shi-Yong; Li, Jin-Long; Jiang, Fu-Wei] College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, PR China;[Lin, Jia] Hubei Key Laboratory of Animal Nutrition and Feed Science, Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Wuhan Polytechnic University, Wuhan 430023, PR China;[Zhu, Shi-Yong] College of Animal Science and Veterinary Medicine, Qingdao Agricultural University, Qingdao 266109, PR China;[Dai, Xue-Yan] Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang 330045, PR China;[Zhao, Yi; Li, Jin-Long] Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment, Northeast Agricultural University, Harbin 150030, PR China
通讯机构：
[Yi Zhao; Jin-Long Li] C;College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, PR China<&wdkj&>Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment, Northeast Agricultural University, Harbin 150030, PR China<&wdkj&>Heilongjiang Key Laboratory for Laboratory Animals and Comparative Medicine, Northeast Agricultural University, Harbin 150030, PR China
摘要：
Atrazine (ATZ) is the most prevalent herbicide that has been widely used in agriculture to control broadleaf weeds and improve crop yield and quality. The heavy use of ATZ has caused serious environmental pollution and toxicity to human health. Lycopene (LYC), is a carotenoid that exhibits numerous health benefits, such as prevention of cardiovascular diseases and nephropathy. However, it remains unclear that whether ATZ causes cardiorenal injury or even cardiorenal syndrome (CRS) and the beneficial role of LYC on it. To test this hypothesis, mice were treated with LYC and/or ATZ for 21days by oral gavage. This study demonstrated that ATZ exposure caused cardiorenal morphological alterations, and several inflammatory cell infiltrations mediated by activating NF-κB signaling pathways. Interestingly, dysregulation of MAPK signaling pathways and MAPK phosphorylation caused by ATZ have been implicated in cardiorenal diseases. ATZ exposure up-regulated cardiac and renal injury associated biomarkers levels that suggested the occurrence of CRS. However, these all changes were reverted, and the phenomenon of CAR was disappeared by LYC co-treatment. Based on our findings, we postulated a novel mechanism to elucidate pesticide-induced CRS and indicated that LYC can be a preventive and therapeutic agent for treating CRS by targeting MAPK/NF-κB signaling pathways.
摘要：
This study aimed to investigate the prevalence of aflatoxin B1 (AFB1) in four kinds of fermented soybean-related products used as traditional Chinese food: fermented soybean (FS), fermented qianzhang (FQ), fermented bean curd (FB) and fermented okara (FO). A total of 203 samples, comprising FS (40 samples), FQ (60), FB (41) and FO (62), were collected from free markets of agricultural food, convenience stores and supermarkets in Hubei province, China from November 2021 to January 2022. The AFB1 contamination in samples was assessed using a validated enzyme-linked immunosorbent assay method. Ninety-eight samples (48.3%) were AFB1-positive with a concentration range of 0.36-11.26 mu g/kg and a mean value of 2.2 mu g/kg. Among the four kinds of products, only FS was found to have some samples (n = 13) with AFB1 levels exceeding China's legal limit of 5 mu g/kg and it had the highest AFB1-positive percentage (97.5%). Moreover, the mean content of AFB1 in the FS samples was significantly higher (p < 0.05) than those in the other three kinds of samples. Therefore, feasible measures are needed to continually monitor and strictly prevent the production of AFB1 in these products, especially FS, to reduce the health risk to consumers of AFB1 exposure.
期刊：
Journal of Hazardous Materials,2023年459:132262 ISSN：0304-3894
通讯作者：
Wang, X;Yang, XZ
作者机构：
[Wang, Xu; Guo, Pu; Wang, Xinru; Hu, Siyi; Lu, Qirong; Yang, Yaqin] Huazhong Agr Univ, Natl Reference Lab Vet Drug Residues HZAU, Wuhan 430070, Hubei, Peoples R China.;[Wang, Xu; Guo, Pu; Wang, Xinru; Hu, Siyi; Lu, Qirong; Yang, Yaqin] Huazhong Agr Univ, MAO Key Lab Detect Vet Drug Residues, Wuhan 430070, Hubei, Peoples R China.;[Wang, Xu; Guo, Pu; Hu, Siyi; Lu, Qirong; Yang, Yaqin] Huazhong Agr Univ, MAO Lab Risk Assessment Qual & Safety Livestock &, Wuhan 430070, Hubei, Peoples R China.;[Yang, XZ; Yang, Xinzhou] South Cent Univ Nationalities, Sch Pharmaceut Sci, Wuhan 430070, Hubei, Peoples R China.;[Guo, Pu; Lu, Qirong] Wuhan Polytech Univ, Hubei Key Lab Anim Nutr & Feed Sci, Wuhan 430023, Peoples R China.
通讯机构：
[Yang, XZ ] S;[Wang, X ] H;Huazhong Agr Univ, Natl Reference Lab Vet Drug Residues HZAU, Wuhan 430070, Hubei, Peoples R China.;Huazhong Agr Univ, MAO Key Lab Detect Vet Drug Residues, Wuhan 430070, Hubei, Peoples R China.;South Cent Univ Nationalities, Sch Pharmaceut Sci, Wuhan 430070, Hubei, Peoples R China.
关键词：
Agonist;BBB;Daucosterol;PGC-1α;T-2 toxin
摘要：
T-2 toxin is a common environmental pollutant and contaminant in food and animal feed that represents a great challenge to human and animal' health throughout the world. Using natural compounds to prevent the detrimental effects of T-2 toxin represents an attractive strategy. Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1 alpha) is a critical regulator in various cellular processes. Recently, PGC-1 alpha activation has been reported to confer protection against neurological injuries. We aimed to identify a potent PGC-1 alpha activator from plants as a chemopreventive compound and to demonstrate the efficacy of the compound in attenuating T-2 toxin-induced blood-brain barrier (BBB) toxicity. We identified daucosterol, which binds directly to the 71-74 (-1100 to -1000 bp) position of the second promoter of human PGC-1 alpha by hydrogen bonding. An in vitro and in vivo T-2 toxin induced BBB injury model revealed that this compound can protect against this injury by increasing transepithelial/transendothelial electrical resistance, reducing sodium fluorescein (NaF) infiltration and increasing the expression of tight junction-related proteins (zonula occludens-1 (ZO-1), occludin (OCLN), claudin-5 (CLDN5)) expression. In conclusion, we identified daucosterol as representing a novel of PGC-1 alpha activators and illustrated the mechanism of specific binding site. Furthermore, we have demonstrated the feasibility of using natural compounds targeting PGC-1 alpha as a therapeutic approach to protect humans from environmental insults that may occur daily such as lipopolysaccharide.
摘要：
Deoxynivalenol (DON) is one of the most prevalent mycotoxins in feed, which causes organ toxicity in animals. Therefore, reducing DON-induced organ toxicity can now be accomplished effectively using protective agents. This review provides an overview of multiple studies on a wide range of protective agents and their molecular mechanisms against DON organ toxicity. Protective agents include plant extracts, yeast products, bacteria, peptides, enzymes, H2, oligosaccharides, amino acids, adsorbents, vitamins and selenium. Among these, biological detoxification of DON using microorganisms to reduce the toxicity of DON without affecting the growth performance of pigs may be the most promising detoxification strategy. This paper also evaluates future developments related to DON detoxification and discusses the detoxification role and application potential of protective agents. This paper provides new perspectives for future research and development of safe and effective feed additives.
摘要：
Recent research has emphasized the significance of investigating the interplay between organelles, with endoplasmic reticulum mitochondria contact sites (ERMCSs) being recognized as critical signaling hubs between organelles. The objective of the current study was to assess the impact of deoxynivalenol (DON) on jejunal mitochondria, ER, and ERMCSs. Twelve piglets (35 d, 10.22 ± 0.35 kg) were randomized into two groups: control group, basal diet; the DON group, basal diet + 1.5 mg/kg DON. The findings revealed that DON decreased growth performance, induced jejunal oxidative stress, and impaired jejunal barrier function. DON was also found to induce mitochondrial dysfunction, trigger endoplasmic reticulum stress (ERS) in the piglets' jejunum, and activate mitochondrial and ER apoptosis pathways by upregulating apoptosis-related proteins (Caspase-8, Caspase-12, Bax, and CHOP). To investigate the involvement of ERMCSs in DON-induced intestinal injury, we measured the protein levels of ERMCS proteins, such as mitofusin 1 (Mfn1), mitofusin 2 (Mfn2), and glucose-regulated protein 75 (GRP75) and Pearson's correlation coefficient of ERMCS proteins and ERMCS ultrastructure. Our finding showed that DON upregulated the protein level of Mfn2 and GRP75 and increased the percentage of mitochondria with ERMCSs/total mitochondria, the length of ERMCSs compared to the perimeter of mitochondria, and the Pearson's correlation coefficient of voltage-dependent anion-selective channel protein 1 (VDAC1) and inositol 1,4,5-triphosphate receptors (IP3Rs) in piglets' jejunum. Furthermore, DON shortened the distance between mitochondria and ER at ERMCSs. These findings suggested that DON impaired mitochondrial function, triggered ERS, and increased ERMCSs, indicating that the increased ERMCSs could be related to mitochondrial dysfunction and ERS involved in the intestinal injury of piglets induced by DON.
通讯机构：
[Ying Ren] H;Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan 430023, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
amaranth hay;growth stage;in vivo digestibility;goat
摘要：
Simple Summary At present, studies on the rumen degradation characteristics of amaranth hay at different growth stages are limited. In the current study, four growth stages (squaring stage (SS), initial bloom stage (IS), full-bloom stage (FS) and mature stage (MS)) were selected. The chemical composition and rumen degradation characteristics of amaranth hay at four stages were studied in detail. Among the four stages, IS was superior in terms of chemical composition and rumen degradability characteristics. The objective of this study was to investigate the rumen degradation characteristics of grain amaranth hay (Amaranthus hypochondriacus) at four different growth stages. The aim of this study was to evaluate the nutritional value of grain amaranth hay at different growth stages by chemical composition, in vivo digestibility, and in situ degradability. Three Boer goats with permanent ruminal fistulas were selected in this study. Amaranthus hay at four different growth stages (squaring stage (SS), initial bloom stage (IS), full-bloom stage (FS) and mature stage (MS)) was crushed and placed into nylon bags. Each sample was set up with three replicates, and two parallel samples were set up in fistulas at each time point. The rumen degradation rates of dry matter (DM), crude protein (CP), neutral detergent fibre (NDF) and acid detergent fibre (ADF) were determined at 0, 6, 12, 24, 36, 48 and 72 h. The results were as follows: (1) The concentration of CP in SS was the highest and was significantly higher than that in other stages (p < 0.05), whereas the contents of NDF and ADF gradually increased with the extension of the growing period and reached a maximum in MS; (2)The degradation of CP in the rumen at 72 h of SS and IS was more than 80%. Compared with other stages, the effective degradability of CP was highest in SS (p < 0.05) and reached 87.05% at 72 h, and the degradation rate was the lowest in MS; and (3) The effective degradability of NDF in IS was the highest (p < 0.05) and reached 69.326% at 72 h. The effective degradability of ADF in MS was the highest (p < 0.05) and reached 65.728% at 72 h. The effective degradability of DM and CP in SS was the highest. In conclusion, among the four stages, IS was superior in chemical composition and rumen degradability characteristics.
摘要：
Aim: Inflammation and apoptosis are main pathological processes that lead to the development of hyperuricemic nephropathy (HN). This study aims to explore whether baicalin (BA) and baicalein (BAI) can relieve the damage through PI3K/AKT/NF-kappa B signal pathway and provide more reliable and precise evidence for the treatment of HN. Methods: HN mice were induced by yeast extract with potassium oxonate (PO), and HK-2 cells were induced by monosodium urate (MSU). Molecular docking, western blot, q-PCR, and other methods were used to explore the changes of various indicators in HN mice and HK-2 cells. Results: Molecular docking results showed that BA and BAI had good binding ability with PI3K, AKT, p65 and I kappa B alpha. BA and BAI significantly ameliorated the levels of renal function, decreased the p-PI3K, p-AKT and p-p65 expression, down-regulated the BAX/BCL2 and CASP3, and blunted the mRNA levels of tumour necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, and IL-18 in both renal tissue of HN mice and HK-2 cells induced by MSU. BA and BAI also decreased the oxidative stress level of MSU-induced HK-2 cells. Conclusion: BA and BAI were confirmed to attenuate HN through alleviating renal inflammatory and apoptosis in cells and tissues by inhibiting PI3K/AKT/NF-kappa B pathway. BA and BAI were expected to be developed as new anti-HN drugs. Summary at a glance Baicalin and baicalein were confirmed to attenuate hyperuricemic nephropathy through alleviating renal inflammatory and apoptosis in cells and tissues by inhibiting PI3K/AKT/NF-kappa B pathway.
作者机构：
[张正帆; 徐朋涛; 侯永清; 何来; 刘志鹏; 王思甜; 刘诚傲; 齐雅; 丁斌鹰; 郑丽云; 郭双双] Engineering Research Center of Feed Protein Resources on Agricultural By-Products, Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan, 430023, China;[童庆芳] Wuhan Jiangxia District Animal Disease Prevention and Control Center, Wuhan, 430072, China
通讯机构：
[Zhang, Z.] E;Engineering Research Center of Feed Protein Resources on Agricultural By-Products, China
摘要：
This research introduced the combined model of pigs with cannulation of blood vessel and terminal ileum fistula, and the deposition of volatile fatty acids (VFA) in large intestine was determined accurately by isotope tracer method to calculate net absorption of VFA. This combined model can provide a thought for studying the endogenous nutrients absorption properties in large intestine of pigs. Abstract Background This study aimed to develop a combined model to quantify the net absorption of volatile fatty acids (VFA) in the large intestine (LI) of pigs. Methods Fifteen female growing pigs (Duroc × Large White × Landrace) were ranked by body weight (30 ± 2.1 kg) on day 0 and assigned to one of three treatments, namely the basal diet containing different crude fiber (CF) levels (LCF: 3.0% CF, MCF: 4.5% CF, and HCF: 6.0% CF). The pigs were implanted with the terminal ileum fistula and the cannulation of the ileal mesenteric vein (IMV), portal vein (PV), and left femoral artery (LFA) from days 6 to 7. [13C]‐Labeled VFA and P‐aminohippuric acid were constantly perfused into the terminal ileum fistula and the cannulation of the IMV (day 15), respectively. Blood samples were collected from the PV and the LFA during perfusion (5 h), and LI samples were collected. Results The net flux of [12C]‐acetic acid in the PV was greater for LCF versus MCF (p = 0.045), but no difference was observed in the net flux of [12C]‐propionic acid (p = 0.505) and [12C]‐butyric acid (p = 0.35) in the PV among treatments. The deposition of [12C]‐acetic acid in the LI was greater for LCF versus MCF (p = 0.014), whereas the deposition of [12C]‐propionic acid (p = 0.007) and [12C]‐butyric acid (p = 0.037) in the LI was greater for LCF versus HCF. Conclusions In conclusion, this pig model was found conducive to study the net absorption of VFAs in the LI, and LCF had more net absorption of VFAs in the LI than MCF and HCF.
