Previous studies have shown that tilmicosin can inhibit porcine reproductive and respiratory disorders syndrome virus(PRRSV)replication in vitro.Here,to further study the inhibitory effect of tilmicosin on PRRSV in vivo,healthy piglets were selected as experimental animal fed with or without tilmicosin.Seven days later,these piglets were artificially infected with a highly pathogenic PRRSV strain.Then,the clinical manifestations,viral replication,mortality and growth performance of the piglets between the tilmicosin treated group and the con-trol group were compared.The results showed that tilmicosin significantly inhibited PRRSV replication in vivo,alleviated disease symptoms,reduced mortality by 20％,and increased daily weight gain of the PRRSV infected piglets.This study provided reference for clinical use of tilmicosin to prevention and control of PRRSV infection.
This study was to establish a rapid field screening method for screening African swine fever(ASF)gene-deleted mutants in or-der to identify the complex infection situation of ASF in China.Based on the epidemic trends of ASFV in China,the specific primers and exo probes were designed and synthesized by analyzing the conserved regions of the ASFV B646L and MGF-505R genes,in order to establish a double real-time RPA method for detection of the above-mentioned mutants.The sensitivity and specificity of the method were analyzed.In addition,the method was tested in clinical application using the optimized RPA.The result indicated that the double real-time RPA method could monitor the detection process within 15 min.Its minimum detection of RPA was up to 10 copies/response for both the genes.The meth-od was highly specific,without cross-reactions with classical swine fever virus,porcine respiratory and reproductive syndrome virus,pseud-orabies virus,porcine parvovirus and porcine circovirus type 2.Then,266 clinical samples were tested using the dual real-time RPA and WOAH recommended real-time PCR,with a coincidence rate of up to 100％.The double real-time RPA method for detecting ASFV MGF-505R gene-deleted mutants could be adapted to the mobile real-time RPA detector,which possessed the advantages of rapidity,high sensi-tivity and strong specificity.The method is applicable for rapid clinical detection of ASFV,and it could serve as a new screening method for prevention and control of ASF.
The aim of the trial was to explore the effect of Alisma powder in alleviating high energy and low protein diet-induced hepatic lipid deposition in laying hens.Seventy-two 260-day-old Hy-Line Variety Brown laying hens were obtained and randomly divided into three groups,namely,the control group(CON,treated with 10.9 MJ/kg metabolizable energy,16.9％crude protein),the high-energy and low-protein diet group(HF,with 13.0 MJ/kg metabolizable energy,12.1％crude protein),and the high-energy low-protein diet supplemented with Alisma powder group(HFA,with 13.0 MJ/kg metabolizable energy,12.1％crude protein,supplemented with 72 mg/kg Alisma pow-der).The hens were housed in cages and subjected to restricted feeding with 110 g/d/head.The room temperature of the chicken house was about 24 ℃,the light regime was 16L:8D,and the test period was 12 weeks.The results showed that the egg production rate,egg weight,egg quality index,plasma alanine aminotransferase activity,total cholesterol and triglyceride concentration in the HF group were not signifi-cantly different from those in the control group(P＞0.05),whereas the content of triglycerides in their liver was significantly(P＜0.05)higher than that of the control group;and adding Alisma powder to the diet significantly alleviated the hepatic lipid deposition of the laying hens,and at the same time significantly(P＜0.05)reversed the up-regulation of fatty acid synthase,acetyl-CoA carboxylase 1 and stearoyl-CoA desaturase-1 mRNA of the hepatic lipid synthetic genes.Simultaneously,the upregulation of hepatic glucocorticoid receptor(GR)mRNA and protein was also significantly alleviated in the hens.These results suggested that Alisma alleviated hepatic lipid metabolic disorder induced by high-energy and low-protein diets by regulating de novo lipogenesis in laying hens.GR might be involved in the signaling pathway of the function of alisma.
In order to investigate the anti-tumour effects of baicalin carbon dots on canine mammary tumour,the carbon dots were prepared hydrothermally using baicalin as the carbon source.The morphological structure and optical properties of the baicalin carbon dots were char-acterized by transmission electron microscopy,infrared spectroscopy,UV-vis absorption spectroscopy and fluorescence spectroscopy.CCK-8 cell test was used to study the inhibitory effect of carbon dots on the proliferation of canine mammary tumour cells CIPp and CMT-7364.The results showed that the baicalin carbon dots were round in shape,uniform and well dispersed,with particle sizes ranging from 3 nm to 6 nm,and lattice spacing of 0.253 nm.The baicalin carbon dots possessed good optical properties.There were hydrophilic groups such as hydrox-yl,amino and carboxyl groups on the surface.The IC50 of the baicalin carbon dots against CIPp and CMT-7364 were 41.65 μg/mL and 42.78 μg/mL,respectively.In summary,baicalin carbon dots with good water solubility showed significant anti-canine mammary tumour activity,which provided ideas for innovation and development of clinical therapeutics for canine mammary tumours.
The aim of this study was to construct a Marc-145 cell line with stable expression of porcine reproductive and respiratory syn-drome virus(PRRSV)N protein by a lentivirus expression system.The N gene was amplified by PCR using PRRSV SH1 strain infectious cloning plasmid as template.Then,the N gene was cloned into the Lentiviral vector,resulting in a recombinant lentivirus plasmid pSin-Ires-Puro-N.The recombinant plasmid pSin-Ires-Puro-N and auxiliary plasmids psPAS2,pMD2.G and pRSV-Rev were co-transfected into 293T cells for lentivirus packaging in order to obtain recombinant lentiviral particles expressing N protein,and the particles were used to infected Marc-145 cells.Next,positive cells were preliminarily screened with puromycin;and after several generations of screening,the Marc-145 cell line with stable expression of N protein was obtained by limited dilution and end-point dilution.PCR amplification of N gene showed that there was N protein gene sequence in the cell line,IFA and Western blot assays verified that N protein could be stably expressed in the cell line.Therefore,we successfully constructed a Marc-145 cell line with stable expression of PRRSV N protein.
