Application of traditional Chinese herbal medicine in the prevention and treatment of swine viral infectious diseases

This study aims to explore the current application status and development prospects of Chinese herbal medicine in preventing and treating swine viral infectious diseases over the past five years.By adopting the method of literature review,we collect,organize,and analyze relevant research literature,with the goal of summarizing and summarizing the research progress in this field.Through research,we found that swine infectious diseases have caused serious economic losses in the breeding industry and that some diseases cannot be fully protected by using vaccines.Therefore,we need new means to prevent diseases.The use of Chinese herbal medicine for the prevention and treatment of related diseases has become a reliable means.This study first briefly introduces the common infectious diseases of pigs and the risks and challenges faced by prevention and treatment,then reads the literature comparing the treatment with Western medicine and traditional Chinese medicine,proving the reliability of traditional Chinese medicine treatment and the unique advantages of Chinese herbal medicine.Afterwards,we summarized the literature on the prevention and treatment of related swine diseases with Chinese herbal medicine in the past five years,and finally made a summary and outlook,hoping to provide ideas for relevant researchers and workers.

Expression and Immunological Analysis of Capsid Protein Precursor of Swine Vesicular Disease Virus HK/70

VP1, a capsid protein of swine vesicular disease virus, was cloned from the SVDV HK/70 strain and inserted into retroviral vector pBABE puro, and expressed in PK15 cells by an retroviral expression system. The ability of the VP1 protein to induce an immune response was then evaluated in guinea pigs. Western blot and ELISA results indicated that the VP1 protein can be recognized by SVDV positive serum, Furthermore, anti-SVDV specific antibodies and lymphocyte proliferation were elicited and increased by VP1 protein after vaccination. These results encourage further work towards the development of a vaccine against SVDV infection.

Association of swine influenza H1N1 pandemic virus(SIV-H1N1p) with porcine respiratory disease complex in sows from commercial pig farms in Colombia

Porcine respiratory disease complex （PRDC） is a serious health problem that mainly affects growing and finishing pigs. PRDC is caused by a combination of viral and bacterial agents, such as porcine reproductive and respiratory syndrome virus （PRRSV）, swine influenza virus （SIV）, Mycoplasma hyopneumoniae （Myh）, Actinobacillus pleuropneumoniae （APP）, Pasteurella multocida and Porcine circovirus 2 （PCV2）. To characterize the specific role of swine influenza virus in PRDC presentation in Colombia, 11 farms from three major production regions in Colombia were examined in this study. Nasal swabs, bronchial lavage and lung tissue samples were obtained from animals displaying symptoms compatible with SIV. Isolation of SIV was performed in 9-day embryonated chicken eggs or Madin-Darby Canine Kidney （MDCK） cells. Positive isolates, identified via the hemagglutination inhibition test, were further analyzed using PCR. Overall, 7 of the 11 farms were positive for SIV. Notably, sequencing of the gene encoding the hemagglutinin （HA） protein led to grouping of strains into circulating viruses identified during the human outbreak of 2009, classified as pandemic H1N1-2009. Serum samples from 198 gilts and multiparous sows between 2008 and 2009 were obtained to determine antibody presence of APP, Myh, PCV2 and PRRSV in both SIV-H1Nlp-negative and -positive farms, but higher levels were recorded for SIV- HI Nlp-positive farms. Odds ratio （OR） and P values revealed statistically significant differences （p〈0.05） in PRDC presentation in gilts and multiparous sows of farms positive for SIV-HINlp. Our findings indicate that positive farms have increased risk of PRDC presentation, in particular, PCV2, APP and Myh.

Effect of Attenuated Highly Pathogenic Pig Reproductive and Respiratory Syndrome(HP-PRRS) TJM-F92 Strain Vaccine on Immune Antibody Levels against Classical Swine Fever(CSF) and Foot-and-Mouth Disease(FMD)

Effects of attenuated highly pathogenic pig reproductive and respiratory syndrome（HP-PRRS）TJM-F92 strain vaccine on immune antibody level against classical swine fever（CSF）and foot-and-mouth disease（FMD）were studied from October 8 to November 12 in 2014,in order to optimize vaccination program of CSF,HP-PRRS and FMD and to provide scientific guidance for animal disease control and prevention work.The results showed that attenuated HP-PRRS（TJMF92 strain）vaccine had no significant effect on immune antibody level of hog cholera lapinized virus（HCLV,ST passage cell vaccine）attenuated vaccine and FMD-O inactivated vaccines（OZK/93 strain）,and single or combined use of three vaccines received good immunization effects.

Eukaryotic Expression and Activity Analysis of Capsid Gene of Swine Vesicular Disease Virus HK/70

The capsid protein precursor （P1）, which plays a major role for the generation of polypeptides of swine vesicular disease virus （SVDV）, was cloned from SVDV HK/70 strain into the retroviral vector pBABE puro and expressed in the mammalian cell line PK15 through the retroviral expression system. The activity of recombinant protein to induce immune response was evaluated in guinea pigs. IFA and Western Blot were used to detect the recombinant protein expression. The results showed that the recombinant protein could be recognized by SVDV positive serum, and animal test showed SVDV-specific antibodies. All of those results indicate that a retroviral-based vaccine carrying the capsid protein precursor （P1） of SVD is able to be expressed in the eukaryotic cell and elicites strong SVDV-specific immune responses in guinea pigs.

Development and Preliminary Application of Double Antibody Sandwich ELISA for Detection of Swine Vesicular Disease Virus

[Objective] The aim of this study was to develop an indirect sandwich EUSA method for detection of swine vesicular disease virus （SVDV）. [Method] High titer serum against SVDV was prepared respectively by inoculated rabbits and guinea pigs with purified virus. To develop an indirect sandwich ELISA, the optimum concentrations of capture antibody, detection antibody, enzyme conjugate and standard antigen were determined using block titration, and positive threshold value was also determined. The specificity, sensitivity and repeatability of the developed IELISA were evaluated using cross-reaction test, comparison test and intra-assay repeated test. In addition, standard samples and clinical samples were detected by this method. [ Result] The best working conditions of the developed ELISA are as follows： capture antibody, 1：400; detection antibody, 1 ： 200; enzyme conjugate, 1 ： 8 000; and standard antigen, 1 ： 4. The positive threshold value was found to be 0.20. For the detection by the developed EUSA, no cross-reaction with foot and mouth disease was observed. The developed ELISA had close sensitivity with ELISA recommended by the World Organisation for Animal Health （OIE） but had sensitivity 2 -4 times higher than that of reverse indirect hernagglutination test. In addition, the developed method also had good reproducibility, and the detection results of standard samples were in line withtheir own background. All the 36 clinical samples were negative in the developed ELISA. [ Conclusion] The developed indirect sandwich ELISA can be used for diagnosis of swine vesicular disease.

Serological Investigation of Swine Reproductive Failure Diseases in Some Large-Scale Pig Farms in Henan Province

[ Objective] To investigate the prevalence situation of swine reproductive failure diseases in Henan Province and provide reference for the immunization and prevention of swine reproductive failure diseases. [ Method] Between May 2009 and April 2010, all serum samples from the Henan Agriculture University, Animal Disease Detection and Diagnosis Center were detected, including 6 825 serum samples for detecting classical swine fever （CSF） antibody, 2 609 for porcine reproductive and respiratory syndrome （PRRS） antibody, 1 177 for pseudorabies rabies virus gE （PRV） antibody, 123 for porcine parvovirus （PPV） antibody and 53 for chlamydiosis antibody. [ Result] The antibody positive rates of sere for de- tecting above five diseases were 63.28%, 61.44%, 25.49%, 39.84% and 5.66%, respectively. [ Conclusion] The immunization and prevention of CSF, PRRS, PPV and PR in Henan Province needs to be strengthened urgently, and the chlamvdiosis has been effectively controlled.

Diagnosis and Prevention of Swine Foot-and-mouth Disease

This paper introduces the characteristics of swine foot-and-mouth disease from the aspects of pathogen,epidemiology,clinical symptoms,and anatomical symptoms,and puts forward clinical comprehensive diagnosis and laboratory diagnostic methods.The disease is distinguished with similar diseases,such as swine pox,porcine vesicular stomatitis,and swine vesicular disease.Finally,the prevention and control measures of the disease are proposed.

Advances in research on the efcacy of traditional Chinese herbal medicine in combating African swine fever

African swine fever(ASF)is a highly contagious disease of domestic and wild pigs caused by African swine fever virus(ASFV).The mortality rate associated with ASF is remarkably high,almost approaching 100%.Since the introduction of ASF into China in 2018,its rapid spread has caused marked economic losses in the country’s swine industry.To date,there are no safe and efective commercial vaccines or antiviral drugs against ASF;thus,there is an urgent need to develop novel prevention and control strategies.Traditional Chinese medicine(TCM),which comprises various herbs that are abundant in various potential functional components,holds great promise for the prevention and control of ASF.Here,we provide a comprehensive review of the advancements in TCM and the efects of its compound formulas against ASF,including the antiviral abilities,immunoregulatory activities,and practical application of these formulas for the prevention and control of ASF.We specifcally examined the potential and constraints of natural product-derived extracts and TCM formulas in combating ASFV.This review aims to ofer insights and ideas for the holistic management and containment of ASF.

Chicken egg yolk antibodies (IgY) as non-antibiotic production enhancers for use in swine production： a review

In recent years, the use of in-feed antibiotics for growth and disease prevention in livestock production has been under severe scrutiny. The use and misuse of in-feed antibiotics has led to problems with drug residues in animal products and increased bacterial resistance. Chicken egg yolk antibodies （IgY） have attracted considerable attention as an alternative to antibiotics to maintain swine health and performance. Oral administration of IgY possesses many advantages over mammalian IgG such as cost-effectiveness, convenience and high yield. This review presents an overview of the potential to use IgY immunotherapy for the prevention and treatment of swine diarrhea diseases and speculates on the future of IgY technology. Included are a review of the potential applications of IgY in the control of enteric infections of either bacterial or viral origin such as enterotoxigenic Escherichia coil, Salmonella spp., rotavirus, porcine transmissible gastroenteritis virus, and porcine epidemic diarrhea virus. Some potential obstacles to the adoption of IgY technology are also discussed.

Application of new biotechnologies for improvements in swine nutrition and pork production

Meeting the increasing demands for high-quality pork protein requires not only improved diets but also biotechnology-based breeding to generate swine with desired production traits.Biotechnology can be classified as the cloning of animals with identical genetic composition or genetic engineering(via recombinant DNA technology and gene editing)to produce genetically modified animals or microorganisms.Cloning helps to conserve species and breeds,particularly those with excellent biological and economical traits.Recombinant DNA technology combines genetic materials from multiple sources into single cells to generate proteins.Gene(genome)editing involves the deletion,insertion or silencing of genes to produce:(a)genetically modified pigs with important production traits;or(b)microorganisms without an ability to resist antimicrobial substances.Current gene-editing tools include the use of zinc finger nuclease(ZFN),transcription activator-like effector nuclease(TALEN),or clustered regularly interspaced short palindromic repeats-associated nuclease-9(CRISPR/Cas9)as editors.ZFN,TALEN,or CRISPR/Cas9 components are delivered into target cells through transfection(lipid-based agents,electroporation,nucleofection,or microinjection)or bacteriophages,depending on cell type and plasmid.Compared to the ZFN and TALEN,CRISPR/Cas9 offers greater ease of design and greater flexibility in genetic engineering,but has a higher frequency of off-target effects.To date,genetically modified pigs have been generated to express bovine growth hormone,bacterial phytase,fungal carbohydrases,plant and C.elagan fatty acid desaturases,and uncoupling protein-1;and to lack myostatin,α-1,3-galactosyltransferase,or CD163(a cellular receptor for the"blue ear disease"virus).Biotechnology holds promise in improving the efficiency of swine production and developing alternatives to antibiotics in the future.

Study of Ontology-Based Swine Diagnosis Technology

The computer swine disease diagnosis is an important tool for swine farming industry, but the traditional expert system cannot meet the requirement of practical application. To improve the situation, a swine disease ontology is constructed, which can model the knowledge of swine disease diagnosis into a concept system, and a mechanism that can save the ontology into relational database is established, further more a computer system is developed to implement ontology- based swine disease diagnosis, so make the diagnosis results extended and more precise.

口蹄疫病毒感染后猪PD-1及其配体转录水平变化和免疫抑制机制分析

研究猪感染口蹄疫病毒(Foot-and-mouth disease virus,FMDV)后程序性死亡受体-1(Programmed death-1,PD-1)及其配体(PD-L1、PD-L2),细胞因子[IL-2(Interleukin-2)、IL-10(Interleukin-10)、IFN-γ(Interferon-γ)]mRNA转录水平和外周血单个核细胞(Peripheral blood mononuclear cells,PBMCs)增殖能力,探讨PD-1/PD-Ls通路在FMDV引起免疫抑制过程中的作用机制。结果表明,猪感染FMDV后3、7、14、17 d,PD-1的mRNA转录水平显著或极显著升高,感染后7 d达到峰值,之后逐渐降低;感染FMDV后3 d和7 d,PD-L1的mRNA转录水平极显著升高;感染FMDV后3 d,PD-L2的mRNA转录水平显著升高。感染FMDV后3、7 d,IL-2的mRNA转录水平显著下降;感染FMDV后1、3 d,IFN-γ的mRNA转录水平极显著下降,IL-2和IFN-γ的mRNA转录水平与PD-1及其配体mRNA转录水平变化趋势相反;感染FMDV后3、7、14 d,IL-10的mRNA转录水平显著或极显著升高,与PD-1及其配体mRNA转录水平变化趋势相同。感染FMDV后,全血中FMDV的病毒载量随着感染后时间的推进逐渐升高,感染后7 d达到峰值,与PD-1及其配体mRNA转录水平变化趋势总体上相同。感染后7 d,PBMCs的增殖能力明显降低。综上,FMDV感染猪后,总体上上调了PD-1及其配体的mRNA转录水平,是FMDV感染引起机体免疫抑制的重要致病机制。

福建省猪源葡萄球菌多重耐药基因的分子流行病学调查

【目的】明确多重耐药基因cfr、optrA和poxtA在福建省猪源葡萄球菌中的分子流行特征,为耐药葡萄球菌的控制提供科学依据。【方法】通过PCR扩增16S rRNA对2020-2022年分离自福建省福州市、厦门市、漳州市、三明市、龙岩市、南平市、宁德市不同猪场的107株菌(样品为鼻拭子、唾液、粪便和肺脏)进行鉴定。对分离菌株进行cfr、optrA和poxtA多重耐药基因检测;采用MEGA软件对cfr和optrA阳性菌株进行系统发育分析;采用琼脂稀释法或微量肉汤稀释法对cfr和optrA基因阳性菌株进行3种抗菌药物(酰胺醇类抗菌药物氟苯尼考和氯霉素,恶唑烷酮类抗菌药物利奈唑胺)最小抑菌浓度(minimum inhibitory concentration,MIC)测定。【结果】经鉴定107株菌均为葡萄球菌,分属18个种,其中以科氏葡萄球菌占比最高。流行病学调查结果显示,107株葡萄球菌主要来自猪鼻拭子样品(占67.3%),并且在福州市猪场的样品中分离率最高(36.4%)。PCR筛查结果显示,在107株葡萄球菌中未检出poxtA基因阳性菌株;检测出14株cfr阳性菌和6株optrA阳性菌,检出率分别为13.1%和5.6%,其中葡萄球菌FJNP2209-1和FJCT2212-1同时携带cfr及optrA基因。系统发育分析结果显示,14株cfr阳性葡萄球菌处于同一个分支内,其中菌株FJFQ2211与所研究的其他菌株亲缘关系稍远;6株optrA基因阳性葡萄球菌属于2个分支。药敏试验结果表明,携带多重耐药基因cfr或optrA的18株葡萄球菌对氯霉素和氟苯尼考100%耐药,对利奈唑胺的耐药率为83.33%。【结论】福建省不同猪场来源的葡萄球菌中多重耐药基因cfr和optrA阳性率较高,但poxtA基因未检出。福建省猪源葡萄球菌对氟苯尼考、氯霉素、利奈唑胺均表现出较高的耐药率,应加强抗菌药物在养猪场中的规范使用。

一起猪水肿病的紧急流行病学调查

2023年7月14—24日,四川省金堂县某生猪代养场仔猪出现神经症状且大量死亡。为找出病因并评估传播风险,赴现场开展了紧急流行病学调查。调查发现,该场共有仔猪4484头,发病857头、死亡583头,袭击率为19.11%,病死率为68.03%。结合现场调查及实验室检测结果,判定这是一起由于气温骤降,圈舍保温措施不足,同时在断奶、疫病等应激下,机体抵抗力降低,致病性大肠杆菌大量繁殖引起的猪水肿病疫情。并舍、静默管理措施及场内生物安全管理不严是疫情在场内扩散的原因。追踪调查显示,疫情外泄风险较小。通过抗生素治疗、及时清理病死猪、强化保暖及生物安全等措施,疫情得到有效控制。该起疫情提示,对断奶仔猪应避免气温突降应激,加强圈舍保温管理,提高仔猪抵抗力,以防引发病原感染,同时养殖场人员应加强生物安全学习,提高饲养管理能力,以防此类事件再次发生。

免疫层析技术在猪常见病毒病快速检测中的应用

免疫层析技术是一类典型的以抗原抗体特异性免疫反应为基础的快速诊断技术,以不同材料作为示踪标记物,具有快速、特异、价格低廉的特点,对猪常见病毒病的现场检测具有广泛的应用价值。本文基于免疫层析技术原理,根据不同的信号表现方式将当前常见的免疫层析技术进行了归类,详细介绍了比色型免疫层析技术,荧光型免疫层析技术的代表性标志物,综述了免疫层析技术在猪常见病毒病快速检测中的应用,并将不同标记物免疫层析试纸条的优点与挑战进行比较,以期为猪病毒病快速检测技术的发展提供思路。

一例规模化猪场流行性腹泻病的诊断与防控风险分析

2022年2月4日,广西壮族自治区某规模化猪场妊娠母猪陆续出现水样腹泻、不吃或少吃料的临床症状,2022年2月6日,产房仔猪出现呕吐、水样腹泻,怕冷扎堆,脱水严重,且传播速度快。通过试剂盒快速检测和实验室检测,诊断为猪流行性腹泻病。针对检测结果对猪群进行紧急疫苗接种和药物治疗,并对此次疫情的发生和发展过程进行防控风险点分析,发现养猪场在生物安全方面存在较大的风险点,通过整改并采取严格的生物安全管理措施后,母猪群发病情况得到缓解,仔猪腹泻窝数下降,猪群趋于稳定,生产成绩逐步恢复。通过对此次案例的分析探讨,为规模化猪场对猪流行性腹泻病的发现和防控提供临床经验,同时增强对流行性腹泻病的风险预警意识,健全规模化猪场对流行性腹泻病的风险预警机制。

2017-2023年眉县猪、牛和羊O型口蹄疫免疫抗体监测与分析

为获知近年来眉县猪、牛和羊口蹄疫的免疫情况,对2017-2023年间全县8个镇(街)共7059份猪、牛和羊血清样品进行抗体检测,并从不同年份、不同季节、不同区域等角度对当地口蹄疫免疫抗体合格率进行比较分析。结果显示,2017-2023年眉县全域猪、牛和羊的口蹄疫免疫抗体合格率均高于70%。其中,牛和羊O型口蹄疫的免疫抗体合格率最高达100%且保持稳定,而猪O型口蹄疫免疫抗体合格率在个别镇(街)较低,低至45%,说明该县近7年间猪、牛和羊口蹄疫免疫抗体合格率总体达到农业农村部的标准(>70%),但针对猪应立即调整现行的免疫流程,加强集中免疫和日常补充免疫,以建立起县域有效的动物免疫保护屏障,确保养殖业健康发展。

2020~2023年广西柳州市猪主要病毒性传染病的流行病学调查与分析

为了解广西柳州地区猪主要病毒性传染病的流行情况及变化规律,本试验应用实时荧光RT-PCR及实时荧光PCR对2020~2023年柳州市部分地区屠宰场、散养猪场和规模猪场的组织、抗凝血、棉拭子进行猪繁殖与呼吸综合征病毒(PRRSV和Nsp21559-1680变异株)、猪瘟病毒(CSFV)、猪圆环病毒2型和3型(PCV2-3)和猪塞内卡A型病病毒(SVA)4种疫病病原检测。检测结果显示:(1)HPRRSV Nsp21559-1680变异株、PRRSV、CSFV、PCV2、PCV3、SVA的病原平均阳性率分别为0.00%(0/191)、8.04%(191/2377)、0.08%(2/2377)、45.23%(992/2193)、32.74%(718/2193)、0.16%(2/1239);(2)PRRSV、PCV2、PCV3感染率较高,CSFV和SVA为零星感染,其中PCV2的感染率呈逐年下降趋势,PRRSV和PCV3的感染率波动较大,2020~2022年呈逐年下降趋势,2023年较2022年的感染率呈上升趋势;(3)PCV2和PCV3在不同年份度中健康猪样品病原阳性率均高于病死猪样品病原阳性率,而PRRSV在不同年份度中健康猪样品病原阳性率均低于病死猪样品病原阳性率;二重感染以PCV2混合其他病毒感染为主,其中PCV2和PCV3感染较为严重,平均感染率为15.18%;(4)三重感染以PRRSV、PCV2、PCV3混合感染较为严重,平均感染率为2.74%。结果表明:PRRSV、PCV2、PCV3是目前对广西柳州市猪群危害较为严重的主要病毒性疫病,且混合感染较为普遍,应进一步加强流行病学监测,并制定科学合理的免疫程序和计划强化各场点的生物安全防控措施,减少病原的污染、传播与流行,促进广西柳州市生猪行业的健康稳定发展。

Intestinal tryptophan metabolism in disease prevention and swine production

Tryptophan(Trp)is an essential amino acid that cannot be synthesized by animals.It has been characterized into two different isomers,levorotation-Trp(L-Trp)and dextrorotation-Trp(D-Trp),based on their distinct molecule orientation.Intestinal epithelial cells and gut microbiota are involved in metabolizing L-Trp in the gut via the activation of the kynurenine,serotonin,and indole pathways.However,knowledge regarding D-Trp metabolism in the gut remains unclear.In this review,we briefly update the current understanding of intestinal L/D-Trp metabolism and the function of their metabolites in modulating the gut physiology and diseases.Finally,we summarize the effects of Trp nutrition on swine production at different stages,including growth performance in weaned piglets and growing pigs,as well as the reproduction performance in sows.