BACKGROUND:Aflatoxin B1 (AFB1) is a potent hepatotoxin that poses significant health risks to both livestock and humans. β-Nicotinamide mononucleotide (NMN) has potential therapeutic benefits for liver diseases. However, its mechanism against AFB1-induced liver injury remains unclear. OBJECTIVE:This study investigates whether NMN supplementation reduces AFB1-induced liver injury through the modulation of the gut-liver axis and elucidates the underlying molecular mechanism. METHODS:Mice were exposed to AFB1 (0.75 mg·kg-1, p.o.) for 2 weeks to induce liver injury, with or without NMN (300 mg·kg-1, p.o.). Changes in gut microbiota were assessed via 16S rRNA sequencing, while bile acids (BAs) profiles were quantified using targeted metabolomics. The farnesoid X receptor (FXR/NR1H4) pathway was analysed using qPCR, western blot and immunofluorescence. To establish causality, antibiotic depletion, faecal microbiota transplantation (FMT) and intestine-specific FXR knockout (FXRΔIE) mice were utilized. RESULTS:NMN supplementation attenuated AFB1-induced liver injury, inflammation and oxidative stress, while restoring intestinal barrier integrity and reducing hepatic bile acids accumulation. Mechanistically, NMN reshaped the gut microbiota, increased bile salt hydrolase (BSH) activity and lowered intestinal conjugated bile acids, which correlated with activation of intestinal FXR/fibroblast growth factor 15 (FGF-15) signalling and suppression of hepatic Cyp7a1 expression. Importantly, antibiotic depletion of gut microbiota abolished NMN protection, whereas FMT from NMN-treated donors conferred resistance. Importantly, NMN failed to protect FXRΔIE mice, demonstrating that intestinal FXR is essential. CONCLUSION:NMN alleviates AFB1-induced liver injury via a gut microbiota-bile acid-FXR axis, highlighting a novel mechanism for its hepatoprotective effects.

Chronic diarrhea in pets features high incidence, often causing vitamin B12 deficiency. Probiotics, which can alleviate or even treat chronic diarrhea by improving intestinal microbial balance, have shown promise. Previously, our laboratory isolated a strain of Limosilactobacillus reuteri (CLAB) with vitamin B12-producing capability from canine feces. However, it had suboptimal palatability and insufficient efficacy against chronic diarrhea and vitamin B12 deficiency. In this study, the CLAB was combined with Enterococcus faecalis and Saccharomyces cerevisiae to formulate a compound probiotic paste. The properties of the paste were comprehensively evaluated via a series of experiments including sensory evaluation, pH testing, microbial colony counting, palatability tests, disease activity index scoring, histopathological analysis, biochemical indicator analysis, and RNA quantification. The results demonstrated that the paste exhibited good stability, safety, and favorable palatability in both dogs and cats. Meanwhile, it significantly alleviated chronic diarrhea and vitamin B12 deficiency in mice. Specifically, the high-dose compound probiotic paste decreased myeloperoxidase and malondialdehyde levels in diarrheic mice from approximately 15.9 and 2.5 nmol/mgprot to about 4.2 and 1.7 nmol/mgprot; increased the total antioxidant capacity content and superoxide dismutase activity from approximately 0.5 nmol/mgprot and 1.0 U/mgprot to about 0.6 nmol/mgprot and 1.6 U/mgprot; and downregulated the relative mRNA levels of interleukin-6, interleukin-1β and tumor necrosis factor-α from approximately 2.1, 2.1 and 2.7 to about 1.2, 1.1 and 1.3, respectively. In conclusion, this study supports the potential use of the compound probiotic paste for preventing and treating chronic diarrhea and improving vitamin B12 deficiency in pets.

AIMS:In recent years, porcine circovirus type 2 (PCV2) has emerged as one of the most economically significant viral pathogens affecting the global swine industry, leading to substantial economic losses. Accumulating evidence indicates that oxidative stress facilitates PCV2 infection and replication, whereas alleviating oxidative stress can attenuate this process. Notably, glutathione and selenium play pivotal roles in the antioxidant response. Accordingly, we selected a glutathione-producing strain of Bacillus pumilus for selenium enrichment and investigated its inhibitory effects on PCV2 replication. This study aims to provide experimental evidence for the development of microecological preparations with antiviral activity. METHODS AND RESULTS:In this study, microbial colony counting, analysis of the biological characteristics of bacteria, histopathological analysis, biochemical indicator analysis, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blotting were used to evaluate the effects of the selenium-enriched Bacillus pumilus composite probiotic on PCV2 replication in a mouse model. The results demonstrated that this Bacillus pumilus strain exhibited high glutathione production, favorable biological characteristics, and strong selenium-enriching capacity. The composite probiotic preparation modulated the JAK/STAT(Janus Kinase/Signal Transducer and Activator of Transcription) signaling pathway and elevated the phosphorylation levels of JAK1, STAT1, and STAT2. This further upregulated the expression of key antiviral effector genes Mx1 and Oas1 in the mouse spleen, thereby inhibiting PCV2 replication in vivo. CONCLUSIONS:In this study, selenium-enriched, glutathione-producing Bacillus pumilus exhibits antiviral potential. It suppresses in vivo PCV2 replication via alleviating oxidative stress, which provides the theoretical basis and experimental support for the development of novel antiviral microecological preparations.

Cholestatic liver disease is a type of severe liver disease that results mainly from the retention of bile acids (BAs). Our study aimed to explore the protective mechanism of Lactobacillus rhamnosus GG-derived extracellular vesicles (LGG-EVs) on hepatic BA synthesis, liver injury and fibrosis in multidrug resistance protein 2 knockout (Mdr2-/-) mice. LGG-EVs markedly attenuated liver injury and fibrosis, concomitant with a substantial reduction in hepatic BA retention in Mdr2-/- mice. The RNA sequencing results demonstrated that the enrichment of differentially expressed genes was associated with lipid metabolism, cholesterol biosynthesis, bile acid metabolism, and the PPAR signalling pathway. LGG-EVs reprogrammed the intestinal flora and enhanced intestinal BA deconjugation. Targeted bile acid metabolomics revealed a pronounced shift: ileal conjugated BAs (TDCA, TUDCA, and THDCA, especially TCA and T alpha/ beta MCA) were extensively reduced, whereas unconjugated species (UDCA, HDCA, CA, alpha/beta/omega MCA and especially DCA) exhibited widespread elevation, which prominently activated the intestinal Farnesoid X receptor (FXR)/Fibroblast growth factor 15 (FGF-15) axis and inhibited hepatic BA synthesis. However, LGG-EVs failed to ameliorate BA synthesis and liver fibrosis in antibiotic-treated Mdr2-/- mice. Furthermore, these alterations were mitigated by intestine-specific FXR inhibitors in Mdr2-/- mice. In conclusion, LGG-EVs ameliorate cholestatic liver disease by reprogramming hepatic metabolism, reshaping the gut microbiota, increasing BSH-mediated bile acid deconjugation and activating the intestinal FXR/FGF-15 axis. These collective findings establish LGG-EVs as a novel and effective therapeutic strategy for cholestatic liver diseases.

OBJECTIVE:Proper assessment of intraoperative abdominal incisional tension helps to select the appropriate sutures and suture method. Wound tension is usually thought to be associated with wound size, but few relevant articles have been reported. The aim of this study was to investigate the core factors influencing abdominal incisional tension and construct regression equations to judge incisional tension in clinical surgery.METHODS:Medical records were collected from clinical surgical cases at the Teaching Animal Hospital of Nanjing Agricultural University from March 2022 to June 2022. The data collected mainly included the body weight, and the incisional length, margin, and tension. The core factors affecting abdominal wall incisional tension were screened by correlation analysis, random forest analysis, and multiple linear regression analysis.RESULTS:Although correlation analysis showed that multiple same and deep layer abdominal incision parameters and body weight were significantly correlated with abdominal incisional tension. However, the same layer of abdominal incisional margin had the largest correlation coefficient. In random forest models, the abdominal incisional margin had the main contribution to the prediction of the same layer's abdominal incisional tension. In the multiple linear regression model, all incisional tension could be predicted by the same layer of abdominal incisional margin as the only independent variable, except for canine muscle and subcutaneous. The canine muscle and subcutaneous incisional tension were binary regressions with the same layer's abdominal incision margin and body weight.CONCLUSION:The same layer's abdominal incisional margin is the core factor positively related to the abdominal incisional tension intraoperatively.

(1) Background: Two-dimensional shear wave elastography (2D-SWE) is a non-invasive method widely used in human medicine to assess the extent of liver fibrosis but only rarely applied to veterinary medicine. This study aimed to measure liver stiffness in healthy dogs and investigate the factors that impacted 2D-SWE measurement. (2) Methods: In total, 55 healthy dogs were enrolled and subjected to 2D-SWE measurements before and after anesthesia administration. Post-anesthesia 2D-SWE measurements and computerized tomography (CT) scans were obtained. (3) Results: The liver stiffness range in healthy dogs was 3.96 ± 0.53 kPa. In a stratified analysis based on confounding factors, liver stiffness was influenced by measurement site and anesthesia, but not by sex. No correlation was observed between liver stiffness and weight or liver CT attenuation. (4) Conclusions: 2D-SWE is feasible for liver stiffness measurement in dogs. Anesthesia and measurement site are sources of variability. Therefore, these factors should be considered while recording 2D-SWE measurements. Our data on liver stiffness in healthy dogs can serve as the basis for future studies on 2D-SWE to assess pathological conditions in dogs.

犬巴贝斯虫病是通过中间媒介蜱传播的一种血液原虫病,该病在春、夏和秋季均可发生,严重地危害到了各类犬只的健康.感染犬在临床上主要表现为精神不振、食欲减退、持续不定期高热、贫血、黄疸、血红蛋白尿等现象.本文就2018年8月26日接诊的一例贵宾犬巴贝斯虫病的诊断、治疗以及护理和预后等进行简要分析,旨在为宠物饲养者和临床宠物医院从业人员提供借鉴或参考.

Twenty one-year-old local male dogs were randomly assigned into four groups (five dogs per group). The control and the ethylene glycol (EG) groups were fed basal diets without and with EG, and the EG+sodium selenite (EG+SS) and EG+selenium yeast (EG+SY) groups were fed basal diets with EG containing SS and SY, respectively. Blood, urine, and renal samples were taken after 18 weeks of feeding. The results showed that compared with the control group, the serum calcium levels and antioxidase activities significantly decreased in the EG group. Serum creatinine, urea nitrogen, and malondialdehyde (MDA) levels and urine calcium and oxalate levels significantly increased. Calcium oxalate crystal deposition and osteopontin (OPN) messenger RNA and protein expression in the renal tissues significantly increased. These changes above in the EG group were reversed within limits by adding selenium in the diets (both EG+SS and EG+SY groups). Further, compared with the EG+SS group, the EG+SY group showed better effects in decreasing the formation of EG-induced calcium oxalate renal calculi and OPN expression and improving antioxidant capability in dogs. It indicates that organic selenium has the potential value to alleviate the formation of EG-induced calcium oxalate renal calculi.

Aeromonads are inhabitants of aquatic ecosystems and are described as being involved in intestinal disturbances and other infections. The purpose of this study was to investigate the production of N-acyl-homoserine lactone (AHL) signal molecules and some virulence factors, including hemolysins, proteases, extracellular nucleases production and cytotoxicity by waterborne Aeromonas hydrophila. A total of 24 strains isolated from fresh-water or diseased fish were used in the study. The majority A.hydrophila strains produce two AHL molecules (21/24), one is N-butanoyl homoserine lactone (BHL), and the other is N-hexanoyl homoserine lactone (HHL) according to thin-layer chromatography analysis. Among the virulence factors tested, more than 83 % of the isolates produced β haemolysin when inoculated on sheep blood agar, only 50 % of the isolates displayed DNase activity, 75 % of the isolates shown proteolytic activity on skimmed milk plate, and cytotoxic activity was detected in 20 of 24 of the isolates. The strains producing AHLs possessed one or more virulence factors. In conclusion, the production of quorum sensing signal molecules is common among the strains that we examined, and there seems to some relationships between quorum sensing signal production and virulence factors in A. hydrophila.

This experiment was designed to compare the effect of two selenium sources at the dosage of therapeutic level on hepatocarcinogenesis and angiogenic cytokines in DEN-induced hepatocarcinoma rats to further approach their possible anticancer's mechanism. One hundred and seventy-eight Sprague-Dawley (SD) rats (average weight being 100-120g) were randomly divided into 5 groups (I-V). Animals in group I, group II and group III served as the negative control, sodium selenite control (SS) and positive controls respectively, and received 0.1, 3.0, and 0.1mg/kg selenium from sodium selenite supplemented diets during the whole experimental time. Rats in group IV and group V were fed with selenium from selenium-enriched malt (SEM) and sodium selenite (SS) supplemented diets (3mg/kg respectively). To balance the nutritional content among each group, normal malt which was not treated with selenium was added into the diets of the challenge groups. The nutrition contents, except the selenium of the diet in each group, were similar and in accordance with NRC standards. Rats in groups III-V were treated by aqueous diethylnitrosamine solution (100mg/L) at the dosage of 10mg/kg body weight every day for 16 weeks to induce hepatocarcinoma, and drank sterilized water for an additional two weeks. Rats in group I and group II drank sterilized water throughout the experiment. At 4th, 8th, 12th, 16th week, five rats in each group were then sacrificed by cervical decapitation. At the termination of the study, at 18th week, the surplus rats were sacrificed by cervical decapitation. Feed was withheld from the rats for 12h before sampling. The number of hepatoma nodules in liver and mortality of rats were calculated. The values of the following items, including α-fetoprotein (AFP), gamma-glutamyltranspeptidase (GGT), tumor necrosis factor-α (TNF-α), insulin-like growth factors-II (IGF-II), nitric oxide (NO) and total nitric oxide synthase (T-NOS) in plasma were determined. At the same time, the positive numbers of vascular endothelial growth factor (VEGF) and protein kinase C-α (PKCα) staining cells in tumor tissue were analyzed by immunohistochemistry using the Envision two step methods with a kit. The results indicated that SEM could significantly decrease the mortality of rats and the number of hepatoma nodules, values of GGT and AFP, and the levels of IGF-II, NO and NOS and lessen the positive numbers of VEGF and PKCα staining cells in tumor tissue. Moreover, SEM could increase the levels of TNF-α in the initiated time of hepatocarcinogenesis, whereas, decrease the levels of TNF-α in the progressive time of hepatocarcinogenesis. SS could only significantly inhibit the positive numbers of PKCα staining cells in tumor tissue, decrease the levels of GGT, AFP and TNF-α at minority sampling times, and increase the levels of NO. In conclusion, SEM could reduce the mortality. It might be related to deaden significantly the lesion of liver, delay the cause of hepatocarcinogenesis, and inhibit the progress of angiogenesis to increase the livability of DEN-induced hepatocarcinoma rats. SS at the same therapeutic dosage had less effect on the hepatocarcinogenesis by inhibiting angiogenesis and relative cytokines to some extent.

In this study, lactic acid bacteria in canine feces were isolated and identified, and their oxalate-degrading capacities were evaluated. The oxalate-degrading capacities were determined for 24 of 47 (51.06%) lactic acid bacteria isolates. Of these, 8 isolates [Leuconostoc mesenteroides (RL75), Lactococcus garvieae (CD2), Lactococcus subsp. lactis (CS21), Enterococcus faecium (CL71 and CL72), and Enterococcus faecalis (CD14, CS62, and CD12)] degraded more than 5% of the oxalate present, while the others degraded less than 5% of the oxalate in vitro. Isolates that degraded more than 5% of the oxalate present were selected for further examination. The oxalate-degrading capacities of individual isolates, a mixture of Enterococcus, a mixture of Lactococcus, and a mixture of the eight isolates were evaluated in media containing different concentrations of glucose (sufficient, insufficient, or no glucose). In comparison with the control medium, all of the individual isolates and mixtures of isolates could degrade oxalate in all three groups (P<0.05). In most cases, the isolates growing in medium with 20 g/L of glucose had higher oxalate-degrading capacities than those growing in medium with 2.5 g/L of glucose or no glucose. The mixture of all isolates showed higher oxalate-degrading capacity than the individual isolates and other mixtures. The oxalate-degrading capacities of the isolates were isolate dependent.

Quorum sensing(QS)is a mechanism by which diverse microorganisms can control specific processes in response to population density.A relatively well-known form of QS among proteobacteria involves production and subsequent response to N-acylated homoserine lactones(AHLs).Quorum sensing inhibition(QSI),targeting AHL-dependent signaling,has been developed as a target for anti-infection drug.In order to detect AHL and it's inhibitors,a convenient and sensitive bioassay was developed based on the production of pigments by Chromobacterium violaceum and Agrobacterium tumefaciens.Using cross-feeding assay and TLC methods,we can detect and identify AHLs.We also developed a simple soft agar overlay protocol,based on pigmentation inhibition,to rapidly screen for the presence of potential QSI by bacteria and plants.This new method is simple,inexpensive and easy to application for the detection of AHLs and QSI.

犬髋关节脱位多因骨盆部受到间接外力引起犬的股骨头离开髋臼,出现后肢肢形异常、运动障碍。从16例髋关节脱位病例可见该病多发于中、大型犬,车祸为其主要发病原因,以上方脱位为多见。X射线摄像可诊断该病。闭合式整复易复发,开放式整复人工圆韧带固定术为治疗该病的有效方法,恰当的护理有利于该病的恢复。

Aeromonas hydrophila is a pathogen that causes disease in a wide range of homeothermic and poikilothermic hosts due to its multifactorial virulence. The production of many of these virulence determinants is associated with high cell density, a phenomenon that might be regulated by quorum sensing. The quorum sensing system regulates the expression of several virulence factors in a wide variety of pathogenic bacteria. To investigate the pathogenic role of quorum sensing system in A. hydrophila, We constructed an ahyI mutant strain of a fish-clinical isolate YJ-1, named YJ-1 Delta AhyI. Compared with the wild-type strain, the ahyI mutant strain exhibited a significant decrease of total extracellular virulent activity, and decreased in biofilm formation, intraperitoneal LD50 of YJ-1 Delta AhyI were more than 10(9) CFU, about 10(4) times higher than the parent strain. These results suggest that A. hydrophila is able to regulate its extracellular virulent factors and biofilm formation by quorum sensing systems, and indicate that disruption of quorum sensing could be a good alternative strategy to combat infections caused by A. hydrophila.

淋巴肉瘤是多类型的肿瘤,犬猫等小动物均有发生.临床上以多中心型、消化型、胸腺型淋巴肉瘤为主.南京农业大学动物医院于2008年3月收治--病犬,经临床症状观察、血液学检查、血液生化检查、组织触片、血液涂片等病理学检查,最后诊断为犬淋巴肉瘤.根据病理组织学和剖检结果,该病例属于多中心型淋巴肉瘤.

嵌顿包茎是指阴茎自包皮口伸出后不能缩回到原位的现象.本病常见于外伤引起阴茎肿胀和体积增大,严重时可造成阴茎坏死.笔者于2008年4月遇到1例公犬在交配过程中其阴茎长期嵌入母犬阴道而发生嵌顿性包茎,使阴茎严重缺血、坏死.采用阴茎截断术和尿道造口术,确保犬恢复排尿功能.现将该病例报告如下.

尿石症是犬的一种常见泌尿道疾病,多发生于中、老年犬和小型犬。根据X射线对结石的透射性可分为阴性结石和阳性结石,阴性结石相对阳性结石较难诊断。本文以实际诊治的病例为主,就阴性结石的诊治情况进行了较为详细的总结,并对其进行定性分析;同时对阴性尿结石形成的生化机理及导致结石发生的一些因素等进行了初步探讨。

犬髋关节脱位多因骨盆部受到间接外力引起犬的股骨头离开髋臼,后肢肢形异常、运动障碍的疾病。从10例髋关节脱位病例可见该病多发于大型犬,车祸为其主要发病原因,以上方脱位为多。X射线摄像可有效诊断该病,闭合式整复易复发,开放式整复为治疗该病的有效方法,恰当的护理有利于该病的恢复。

吸吮线虫病是由结膜吸吮线虫寄生于眼部所引起的一种人畜共患病.鉴于我国犬的病例上报道极少,笔者根据所诊治的病例,从它的症状、诊断、治疗、流行病学以及虫体的生活史和形态学进行了较详细的描述,以便对该病的诊治为兽医同行提供参考.

The field cases of canine urolithiasis was obtained from 5 representative animal hospitals in Nanjing area for recent two years.In the same time,the composition of 84 canine urinary stones was analyzed by Fourier transform infrared(FTIR) spectroscopy,X-ray energy dispersive spectrometer(EDS) and scanning electron microscope.The results indicated that:(1)The incidence of canine urolithiasis was 0.58%-1.31% in Nanjing area.Of the field urolithiasis cases,the male canine was 54.02% and the female 45.98%.(2)Four types of canine urinary calculi(magnesium ammonium phosphate(struvite),calcium oxalate,urate,calcium phosphate) were defined on the basis of their main constituent.In addition,the characteristic microstructure and etiology of the urinary stone was described and discussed.