猪乳中猪瘟IgG、IgM抗体与猪瘟母源抗体变化规律

选取母猪20头,分为2组,10头／组。免疫组母猪分别于配种前25d、10d进行2次猪瘟疫苗的免疫接种,4头份／次,肌肉注射。对照组接种疫苗稀释液,1mL／头。待母猪分娩后3h采集乳样,并分别于产后2d、3d、4d、5d、6d、7d、8d、9d、10d、15d、20d、25d、30d采集乳样。用间接ELISA方法,测定猪瘟IgG、IgM抗体OD值,并绘制动态变化曲线,观察抗体动态变化规律。待上述免疫组母猪产仔后,各组随机选取10头仔猪,仔猪分别于产后0（未吃初乳）、5、10、15、25、35、40、50、60、70、80、90日龄前腔静脉采血,分离血清,用间接ELISA法检测其母源猪瘟抗体动态变化规律。结果表明：免疫组母猪乳清中IgG、IgM抗体效价的最高值均出现在分娩后1d,随后抗体效价迅速降低,一般泌乳7d以后,免疫组母猪乳中各种抗体效价与常乳基本一致。初生仔猪的母源抗体在5～10日龄达到高峰,10日龄后开始下降,至25日龄保护率已达不到100％,抗体水平接近保护线。     

不同剂量猪瘟疫苗对母猪免疫效价的影响研究

选择220±10日龄后备母猪90头，将其随机分成5组（每组18头）进行对比试验，在220日龄左右和头胎产仔后21天，Ⅰ组用1头份猪瘟脾淋苗免疫，Ⅱ组用2头份猪瘟脾淋苗免疫，Ⅲ组用3头份猪瘟脾淋苗免疫，Ⅳ组用4头份猪瘟脾淋苗免疫，Ⅴ组为空白对照组。然后分别在两次免疫后20、40、60、90、120天以及产后20天采集血清作猪瘟抗体监测，研究其抗体消长规律。结果表明：免疫注射1～4头份猪瘟脾淋苗对母猪的产仔数等繁殖性能无影响；但从抗体水平检测表明最佳免疫剂量为3头份。     

新疆乌鲁木齐垦区猪瘟免疫程序的确定

多年来,新疆乌鲁木齐垦区猪瘟免疫程序较为混乱,各场免疫效果亦不同。为探讨一种适合本地区的猪瘟免疫程序,有效预防猪瘟,进行本试验。本试验对仔猪猪瘟母源抗体进行跟踪监测,对不同日龄仔猪免疫猪瘟疫苗,然后采集血样,检测猪瘟抗体效价。根据效价不断校正,最终确定为科学合理的猪瘟免疫程序,其免疫程序是:猪瘟的超前免疫,剂量1头份;根据抗体效价下降情况,35日龄进行二免,剂量4头份。仔猪常规免疫:一免30日龄,剂量2头份;二免50日龄,剂量4头份。生产母猪免疫:配种前(后)15d进行免疫,剂量4头份。     

猪瘟灭活疫苗免疫抗体消长规律研究

试验选取40日龄育肥猪30头,分为试验疫苗1头份组,试验疫苗2头份组,自购疫苗组2头份组。选取18~24月龄经产母猪30头,分为试验疫苗2头份组,试验疫苗4头份组,自购疫苗组4头份组。在接种前至接种后4个月分时间点采集血液样本,通过ELISA法和IHA法测定分离到的血清的抗体效价。结果表明,高剂量组的抗体水平曲线下降比较平缓,保持较高抗体水平的时间较长。试验用两种疫苗均能在短期内刺激机体产生猪瘟抗体,有效保护仔猪免受猪瘟病毒感染。ELISA法和IHA法均具有很好的特异性,适用于日常的猪群免疫抗体水平的检测。     

浙江省规模化猪场猪瘟免疫状况监测

应用正向间接血凝试验分别检测了46个规模化猪场1075头母猪、9个规模化猪场198头育肥猪、规模化猪场72头断奶前仔猪和13个规模化猪场296头断奶后仔猪血清的猪瘟抗体效价。结果，母猪、育肥猪、断奶前仔猪和断奶后仔猪分别为149、65、3和110份血清抗体效价≤1∶8，低于临界保护线；分别有926、133、69和186份血清抗体效价≥1∶16，视为免疫合格，免疫合格率分别为86．17％、67．17％、85．83％，检测结果表明，断奶后仔猪和育肥猪免疫效果不理想。     

不同类型猪瘟疫苗不同剂量的免疫对比试验

挑选体形和健康状况相近、未免疫猪瘟疫苗的14栏50~55日龄保育猪,随机分成7组,每组2栏,每栏20~21头。7组猪于55~60日龄分别免疫猪瘟细胞苗A 1头份/头和2头份/头、猪瘟细胞苗B 1头份/头和2头份/头、猪瘟细胞苗C 1头份/头和2头份/头与猪瘟兔源脾淋苗D 2头份/头。在免疫前后不同时间点采血、分离血清,应用ELISA方法对采集的784份血清检测猪瘟抗体。不同类型的猪瘟疫苗免疫试验结果表明,猪瘟细胞苗B、C的免疫效果较好,不同疫苗免疫后的抗体水平差异显著。不同免疫剂量的试验结果显示,细胞苗以1头份/头与2头份/头的剂量免疫后抗体水平差异不显著。     

猪瘟免疫程序筛选优化研究

猪瘟是目前危害养猪业的主要疾病之一,其主要控制方法是免疫。为了制定科学合理的猪瘟免疫程序,特进行本试验。试验主要采用猪瘟兔化弱毒疫苗于不同日龄、不同剂量对母猪、生长育肥猪进行注射免疫,然后定期采集试验猪血清检测猪瘟抗体水平。结果显示,母猪于产后30d4头份剂量免疫,其抗体水平保持最好,至分娩前2周抗体仍保持在7d以上,其所生仔猪母源抗体log2值4以上持续到40日龄以后;生长育肥猪30日龄4头份剂量首免,60日龄6头份剂量二免。应坚持猪瘟抗体水平监测,依据本场具体情况随时调整猪瘟免疫程序,从而达到控制猪瘟的目的。     

猪瘟威胁区猪场仔猪免疫程序的探讨

对猪瘟威胁区仔猪不同首免日龄、不同免疫剂量及不同免疫次数的免疫效果进行比较。结果显示，仔猪28日龄首免比25日龄首免的抗体水平略高；首免剂量2头份仔猪的免疫效果不及4头份和6头份的仔猪；28日龄首免4头份、5日龄二免2－4头份，免疫仔猪的抗体阳性率和抗体效价均高，抗体持续期亦较长，35日龄一次免疫4头份仔猪的免疫效果不稳定，平均抗体效价低于1：16。在猪瘟威胁区以28日龄首免4头份、55日龄二免2头份的免疫程序免疫效果较为可靠。     

猪瘟母源抗体衰减及保护水平分析

为分析仔猪体内猪瘟母源抗体的衰减规律及母源抗体保护水平,测定了断奶时母猪和仔猪抗体水平,并监测仔猪母源抗体水平至81日龄;分别对12头81日龄仔猪（来自5头母猪）和25头35日龄仔猪（来自5头母猪）进行了攻毒试验,并用RT—nPCR进行了跟踪检测,对7头攻毒耐过猪用兔体中和法测定了中和效价。结果表明,母猪抗体水平不均衡会导致仔猪群体母源抗体水平不均衡;仔猪群体抗体到60日龄时仍然有67％（12／18）的个体用ELISA检测阻断率在50％以上：81日龄攻毒组有3头（3／12）耐过,35日龄攻毒组能全部耐过（25／25）,但有2头（2／25）在攻毒27d后仍然呈PCR阳性,此时中和抗体水平从低于1：4到1：16不等,推测中和抗体水平1：8～1：16是母源抗体保护的临界线。     

金华猪仔猪猪瘟母源抗体衰减规律初探

仔猪吸吮经猪瘟疫苗免疫的母猪的初乳后,对10头母猪和各所产仔猪中的任意2头在14、21、28、35日龄分别采血,采用正向间接血凝试验检测猪瘟抗体水平,监测母源抗体在仔猪体内的消长规律,以探索金华猪仔猪猪瘟疫苗最佳首免时间;检测母猪抗体水平以探索对仔猪母源抗体的影响。结果发现,仔猪母源抗体水平随着日龄增大而逐级降低,半衰期为17d左右;仔猪母源抗体水平与母猪抗体水平成正比,随着日龄的增加母猪对仔猪母源抗体影响越来越低。     

用单克隆抗体纯化酶联免疫吸附试验监测猪瘟抗体发现隐性猪瘟

用单克隆抗体纯化酶联免疫吸附试验监测瘟血清抗体。测得该场母猪４０份血清样品中，猪瘟弱毒抗体效价ＯＤ值较高，有１００％保护率，测得仔猛进４０份血清样品中，猪瘟弱毒抗体效价ＯＤ值适中，有８７．６％的保护率。     

猪瘟病毒持续感染对母猪繁殖性能及仔猪猪瘟疫苗免疫效力的影响

利用来源于同一猪场的2头猪瘟病毒(HCV)持续感染的带毒母猪及所产35头仔猪(包括13头死胎)和6头阴性对照猪,观察母猪的胎儿发育成活状况、仔猪HCV带毒率及HCV垂直传播对仔猪猪瘟兔化弱毒疫苗(HCLV)免疫效力的干扰作用,同时进行水平传播试验和观察HCV持续感染对母猪繁殖功能的影响。结果表明：HCV持续感染对其中1头母猪的胎儿发育和成活有明显影响,而对另1头母猪的胎儿发育没有明显影响;HCV持续感染母猪可经过胎盘垂直传播病毒给仔猪,传播率达45％～86％;吃初乳和接种HCLV不能阻止带毒仔猪的死亡,9头带毒仔猪在45d内死亡4头;免疫HCLV不能使带毒仔猪产生免疫保护力。5头猪在强毒攻击后死亡4头;HCV垂直传播的带毒猪可发生水平传播,并引起3／4感染猪死亡;HCV持续感染可引起母猪生殖系统病理变化。导致繁殖障碍。     

Bovine Viral Diarrhea Virus in Swine: Neutralizing Antibody in Naturally and Experimentally Infected Swine

Neutralizing antibodies against bovine viral diarrhea virus (BVDV) were detected in sera of Iowa farm sows, their piglets derived by hysterectomy and in specific-pathogen-free (SPF) pigs in a closed herd. No antibodies against BVDV were detected in sera of 134 fetal pigs from 67 sows in an Iowa slaughter-house. Neutralizing antibodies against BVDV or hog cholera virus, produced experimentally in SPF pigs, were demonstrated to be due to different antigens rather than to a common antigen, although slight cross-neutralization reactions sometimes occur.     

Hog Cholera: V. Demonstration of the Antigen in Swine Tissues by the Fluorescent Antibody Technique

The fluorescent antibody technique was employed to detect hog cholera virus in tissue sections of various organs from experimentally infected swine. The method proved to be highly sensitive and infection could be detected in these animals as early as three days after inoculation with the virus. Best results were obtained when tissues were collected from young animals in advanced disease rather than from sows or from pigs in the early febrile phase. Tonsil, spleen and lymph node were the tissues of choice and were most satisfactory when removed from freshly killed animals rather than from those that had died.     

应用FA及PPA-ELISA技术对猪瘟的检测

用免疫荧光抗体诊断技术及单克隆抗体纯化酶联免疫吸附试验诊断技术对疑为猪瘟病毒感染猪进行了检测 ,重点阐述了 2种方法的技术原理和操作过程。通过用免疫荧光抗体诊断技术检测了 5份病料 ,其中有 2份为阳性 ,阳性率为 40 % ;用单克隆抗体纯化酶联免疫吸附试验诊断技术检测了猪瘟血清抗体 ,在 40头母猪血清样品中 ,猪瘟弱毒抗体效价 OD值较高 ,有 1 0 0 %的保护率 ,但是发现母猪群中有 1 0 %隐性猪瘟感染 ,其强毒抗体效价 OD值大于 0 .5,体内带有猪瘟病毒。结果及过程表明此两种诊断方法检测快速、鉴别准确、分辨率高     

Hog Cholera II: Reliability of the Agar Double Diffusion Precipitation Test for the Differentiation of H. C. Virus from Other Infectious Agents in Swine Tissue

The specificity in the agar diffusion precipitation test of the reaction between the antigen of hog cholera virus diffusing from infected tissues and its homologous antibody was verified.

Alternate freezing and thawing of infected tissues was found to give optimum release of the antigen from fresh tissue frozen for 18 hours. A study of the effect of the size and age of pigs upon the diffusion of the antigen from tissues showed that tissues from pigs of less than 250 lbs. gave good results provided the tissues were from animals showing gross clinical manifestations. Specimens from infected breeding sows and dead animals usually did not give a reaction.

     

Antibodies to some swine diseases in commercial piggeries in Central Zambia.

Blood samples were taken from 121 sows and gilts on 7 commercial piggeries located around Lusaka (Zambia). The samples tested negative for antibodies to Aujeszky's disease, transmissible gastroenteritis (TGE), swine influenza, hog cholera and brucellosis. Seventy-eight pigs from 5 farms had positive titres to porcine parvovirus. Eighteen sera showed positive titres to Leptospira celledoni.     

Vaccination of Pigs Against Hog Cholera (Classical Swine Fever) With a Detergent Split Vaccine

Four pigs were inoculated subcutaneously with a detergent (triton X 100) split hog cholera virus in Freund’s incomplete adjuvant. Four other pigs were in the same way inoculated with a detergent split bovine viral diarrhoea virus, also in Freund’s incomplete adjuvant. In the experiment were used 3 control pigs. The vaccinations were repeated after 3 weeks. All pigs were challenged with highly virulent hog cholera virus (Tübingen) 12 weeks after primary inoculations. Signs of hog cholera were only noted in the control pigs.This introductory experiment was succeeded by a larger experiment with subcutaneous inoculations of: 10 pigs with detergent split hog cholera virus in Freund’s incomplete adjuvant, 10 pigs with detergent split hog cholera virus in a saponin (Quil A) solution, 10 pigs with detergent split bovine viral diarrhoea virus in Freund’s incomplete adjuvant, 10 pigs with detergent split bovine viral diarrhoea virus in the Quil A solution plus 5 control pigs. The vaccinations were repeated after 3 weeks, and finally all pigs were challenged 9 weeks later with the highly virulent hog cholera virus strain.With the exception of 1 animal which died accidentally, all animals survived in the groups inoculated with the Quil A vaccines and in the group inoculated with the detergent split hog cholera virus/oil adjuvant vaccine. In the group inoculated with the detergent split bovine viral diarrhoea virus/oil adjuvant vaccine, some of the pigs died of hog cholera.     

猪瘟淋脾毒耐热保护剂活疫苗的中试生产及区域试验

按照拟定的猪瘟淋脾毒耐热保护剂活疫苗制造工艺在辽宁益康生物药品厂进行了5批该疫苗的中试生产,计15万头份,检验全部合格.在北京、河北等地选择9个猪场进行区域试验,共免疫3个品种约3万余头猪,均安全、未显现任何不良反应,跟踪观察,免疫过的猪未发生猪瘟,表明该疫苗安全有效.     

猪瘟兔化弱毒疫苗与我国近年猪瘟野毒的免疫保护相关性试验

２批猪瘟兔化毒睾丸细胞苗分别来自两家兽医生物药品厂，各分别免疫接种猪只，随后以５株猪瘟病毒野毒分别攻击，疫苗接种猪完全存活，对照猪完全死亡。此５株野毒分离自国内不同地区，并皆已经过细致的鉴定，以免疫荧光技术对猪扁桃体进行了活体检查，各对照猪材料上能在攻击后一周时出现病毒，而疫苗接种猪在整个观察期间未出现病毒，据此，显然可见猪瘟兔化毒细胞苗在预防国内猪瘟上极有效力