用MAB-ELISA对仔猪母源猪瘟抗体的试验

用猪瘟兔化弱毒苗4头份免疫后的母猪3头，分别于分娩后定期日龄采血分离24头份血清样品，初生仔猪16头，分别于出生后定期日龄前腔静脉采血分离128头份血清样品，用单抗酶联免疫吸附试验检测血清猪瘟抗体滴度，结果表明，母猪猪瘟抗体效价持续较高，达100％保护率，哺乳前仔猪抗体效价为0，吃初乳后抗体水平不断提高，但抗体总体效价较低，仅有57．89％的保护率；仔猪20日龄前平源抗体水平差异较大，与母猪抗体水平不呈正相关。     

养猪场猪瘟净化技术研究

在４个流行仔猪猪瘟半年以上的养猪场实施了初乳前猪瘟首免的方法，进一步证实了这种免疫方法的免疫可靠性。随后，建立了以实施初乳前首免、建立严格隔离检疫和消毒制度、淘汰可疑带病毒母猪、建立健康种猪群等技术措施为主要内容的猪瘟净化技术，并在一个连续多年经常散发或暴发猪瘟的某养猪场应用，经连续３年多的临床和实验室检测，未发现临床病猪和健康带毒猪。     

猪瘟和链球菌病混合感染的诊治

猪瘟是由猪瘟病毒引起的猪的一种高度接触性、传染性疾病,猪链球菌病是由猪链球菌引起的一种人畜共患传染病。某猪场存栏基础母猪180头,于2005年4月起开始发病,并陆续死亡。根据流行病学调查,临床症状观察,病理剖检和实验室诊断,确诊为猪瘟和猪链球菌混合感染,采取相应的防治措施,于1周后控制了疫情。     

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.     

Evaluation of immunoglobulin G concentration in colostrum of mares by ELISA, refractometry and colostrometry

In 360 samples of colostrum and 36 samples of blood of warmblood mares, the concentration of immunoglobulin G (IgG) was evaluated in the post partal period with an ELISA and the results were compared to values obtained with 2 field methods--refractometry and colostrometry. A significant correlation (p < 0.0001) was determined between ELISA and colostrometry (r = +0.88) and between ELISA and refractometry (r = +0.93). So both field-methods seem suitable for evaluation of the colostral IgG-concentration in mares. Further the kinetic of the IgG concentration in colostrum, the volume of colostrum and the total amount of IgG was measured in the 12 hours post partum (p.p.) in each half udder of 36 mares of different parity. Immediately p.p. primiparous mares have a greater mean concentration of IgG (68 mg/ml) than multiparous mares (51 mg/ml). However, multiparous mares have a mean colostral volume of 1020 ml whereas, in primiparous mares, a mean volume of 527 ml was determined within the first three hours p.p. As a result of this the total amount of IgG was lower in primiparous (31.5 g) than in multiparous mares (48.5 g). A significant decrease of IgG concentration was measured in multiparous mares in the 1.5 hours following partum versus 3 hours in primiparous mares. The mean IgG concentration in the blood serum of the 36 mares immediately p.p. was 13.4 +/- 3.6 mg/ml. No significant correlation was observed between values of IgG concentration in the blood and in the colostrum of the mares.     

生物发酵床条件下育肥猪疾病控制效果观察

通过建立生物发酵床,利用垫料中有益菌群的占位、生物热消毒、杀菌抑菌原理,配套疾病综合控制措施,对比观察了育肥猪的疾病发生情况。结果表明:发酵床条件下育肥猪的发病率降低了10.07%;因病死亡率降低1.65%;头均防治费降低5.60元,降低了52.8%;场内原有的猪瘟、猪丹毒、猪肺疫、仔猪副伤寒、传染性鼻炎、关节炎的发病得到了有效控制;胃肠炎、蛔虫、疥癣及感冒等的发病率也出现大幅度下降趋势,分别降低8.5%、12.1%、10.6%和3.8%,;生物发酵床改善了猪舍环境,增强了猪的体况,提高了免疫效果,保障了猪群的健康。     

Investigation of some factors which influence the absorption of IgG by the neonatal piglet

The absorption by the neonatal gut of purified swine IgG isolated from maternal serum was studied in 91 motherless piglets raised without swine colostrum, to investigate some of the factors which influence absorption. Factors studied included the amount of IgG administered, the effect of bovine colostrum fed concurrently, the influence of starvation and the effect of lactose.Administration of iodinated IgG within 3 hours after birth resulted in the appearance of IgG in the piglet circulation in unaltered form. Immediate feeding of bovine colostrum followed by administration of iodinated IgG at 72 hours resulted in the appearance of only IgG digestion fragments in the circulation.Administration of 15 g of lactose during the first 24 hours reduced absorption of IgG by 26% compared to controls while treatment with 54 g of lactose reduced absorption by 94%. On the contrary, when bovine colostrum was administered immediately after purified IgG, the amount of swine IgG absorbed was 50–70% greater than in controls. Mature milk failed to have the same influence. Finally, in experiments in which the amount of purified swine IgG administered varied from 1.0 to 8.0 g, absorption was directly proportional to the amount administered. When these data were compared with data on naturally reared piglets, the same proportionality was seen and indicated a consistent 1:2.5 to 1:3 ratio of ingested IgG (g) to the maximal serum level of immunglobulin (mg/ml) resulting from absorption. IgA and IgM follow a similar pattern.The data are consistent with a regulated absorption mechanism, that appears to be lost very quickly after the initial ingestion of food. Heterologous protein and lactose alone can switch off this absorption mechanism, thus arguing against “gut closure” by a mechanism of receptor saturation by absorbed IgG. Bovine colostrum, when compared to mature milk, is able to augment the absorption of swine IgG by an unknown mechanism.     

Immunoglobulins in piglets from sows heat-stressed prepartum

Sows were subjected to moderate heat stress in a chamber (32 C) from d 100 of pregnancy until less than 8 h before delivery of first piglet, while control sows were in a thermoneutral chamber (21 C) or farrowing house (22 C). Blood serum and colostrum at parturition of heat-stressed sows and their piglets' serum at birth had elevated cortisol concentrations. Total protein, globulin and immunoglobulin G (IgG) concentrations in sow serum tended to decrease as parturition time was approached; albumin did not change. Total protein and IgG concentrations in colostrum at parturition and in milk 24 and 48 h later tended to be lower in heat-stressed sows. Concentrations of these four protein fractions (total, globulin, IgG and albumin) in piglet serum at birth did not differ among treatment groups, but soon after colostrum ingestion they increased markedly in all groups. Therefore, in all groups total protein remained constant while globulin and IgG decreased. Globulin concentration on d 1 was lowest in piglets from heat-stressed sows, but its rate of decrease after d 1 was not affected by sow treatment. Immunoglobulin G concentration was 11 mg/ml lower, but its rate of decrease through postnatal d 20 was slower in piglets from heat-stressed sows than in those from control sows; a 10-mg/ml difference in IgG concentration on postnatal d 1 has been associated with increased preweaning mortality in piglets. Higher cortisol concentration in serum and lower IgG in colostrum of sows under heat stress was associated in their piglets with higher serum cortisol at birth and lower serum IgG for the first 20 d postnatum.     

Dynamic changes of immunoglobulin concentrations in pig colostrum and serum around parturition

The aim of the study was the determination of IgA, IgM and IgG concentrations in porcine serum and colostrum, in order to evaluate their variations in the perinatal period, as well as to clarify whether there is a correlation between colostrum intake, initial level of immunoglobulins (Ig) in piglet serum and development of their own immunity. The mean IgA, IgM and IgG concentrations in sow serum 10 days before parturition were 1.58, 6.12 and 39.56 mg/ml, respectively. Seven days later only the IgG level was insignificantly lower (34.94 mg/ml, p = 0.55), while concentrations of IgA and IgM increased to 2.25 and 7.25 mg/ml, respectively (p = 0.23 and 0.62, respectively). The mean initial IgG concentration in colostrum at farrowing was 118.5 mg/ml and differed between sows. The average value of IgA in colostrum at birth was 23.8 mg/ml and decreased to 7.85 mg/ml at 6 hours (h) and to 4.59 mg/ml at 24 h after the onset of farrowing. IgM concentration at birth was 12.1 mg/ml and decreased to 4.23 mg/ml at 24 h postpartum. Positive relationships were found between concentrations of IgM and IgA in serum of piglets at 14 and 56 days of life (r = 0.41 and 0.80, respectively, p < or = 0.05) as well as for IgG concentration in the piglets serum at 7 days and 56 days of age (r = 0.48, p < or = 0.05). The above observations suggest that there is a correlation between the level of Ig in piglet serum in the first days of life and improvement of their own immunity.     

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。     

Changes in colostral and serum IgG content in swine in relation to time

Changes in the IgG concentration in the colostrum from separate teats of 6 sows and those in the sera of their 38 piglets were investigated. Colostrum was frequently sampled from parturition to 120 hours and blood was taken from the piglets from birth to 10 weeks of age. The IgG content of the colostrum decreased to 3.2% of the original concentration at the 5th day of lactation. The meaningful variation of the IgG concentration of the colostra obtained from different teats increased rapidly from 12 hours postpartum. Between-sow variation was high and no correlation of the IgG concentration of the colostrum with the average serum level of the corresponding litter could be confirmed. Of the newborn pigs, 33% possessed IgG before ingesting colostrum, the observed concentration was 0.09±0.02 mg/ml (mean±SEM). At 0.5 and 1.5 hours after access to colostrum, this value was 2.30±1.38 and 1.89±0.60 mg/ml respectively. The highest IgG concentration (39.45±1.46) was observed at 24 hours after birth. Following that, a stepwise drop occurred in the IgG level and the lowest value was observed in the 4th week of age (8.92±0.59 mg/ml). Subsequently, there was a continuous rise until 10 weeks of age when the concentration reached the value characteristic of adults. The calculated half-life of the IgG in the sera showed a significant between-litter variation. The average half-life of the serum IgG of pigs was 9.73 days.     

Mammary Secretion of IgG in Sows

The IgG-concentration was determined in serum of 3 pregnant sows before and after partus and in colostrum of 7 sows 0–6 days post partum. The IgG-concentration decreased in serum before partus and increased after partus. The lowest value (1.5 g/100 ml) was observed at partus. The results indicate that IgG is transmitted from serum to colostrum.The concentration of IgG in colostrum was found to be 2.1–10.4 g/100 ml at partus. The concentration decreased very fast during the first day post partum. During 3–6 days post partum the IgG concentration was rather constant (0.3–0.5 g/100 ml). The importance of the results for the passive immunization of piglets is discussed.     

The Transmission of Hog Cholera Virus by Trichinella Spiralis Larvae

Studies have been carried out to determine (a) the possible role of T. spiralis larvae in the transmission of hog cholera virus and (b) to determine the effect of elevated swine temperature on the viability of trichinae. Trichina larvae from hog cholera infected swine were freed from diaphragmatic tissue by artificial digestion. Washed and disinfected larvae transmitted hog cholera virus while the supernatant digestive fluid did not transmit the virus. Infectivity of the virus was lost when the larvae were transmitted through albino rats before administration to swine. Temperature elevation of the swine did not affect the viability of the trichinae.     

An Evaluation of the Amylase and Haemolytic Tests for the Diagnosis of Hog Cholera

The amylase and haemolytic tests recommended for the diagnosis of hog cholera were used on normal swine, hog cholera-infected swine, hog cholera-immune swine and swine with some other virus diseases. The results obtained show that these tests do not appear to be sufficiently reliable for specific laboratory diagnosis.     

母猪FcRn基因多态性及其对初乳中IgG含量的影响

对猪IgG C片段受体基因(FcRn)的单链构象多态性进行分析,在FcRn基因Site1位点即第3外显子的147处碱基发现T突变为C和在Site6位点即第6外显子的1 040处碱基发现C突变为G,其中外显子6的碱基突变使苏氨酸变为精氨酸。在3个品种207头母猪样本中检验多态位点和初乳中IgG含量的相关性,建立固定效应模型进行最小二乘分析,对不同基因型的初乳中IgG含量进行差异显著性检验。结果表明:试验群体中Site1位点的突变对初乳中IgG含量没有显著影响(P>0.05),Site6位点的突变对初乳中IgG含量有显著影响(P<0.05),多重t检验结果表明Site6位点不同基因型的初乳中IgG含量差异显著(P<0.05):CC型的初乳中IgG含量最高,DD型的初乳中IgG含量最低,说明FcRn基因可以作为猪初乳中IgG含量的候选基因之一。     

猪乙型脑炎病毒SA14-14-2疫苗株基础种子的鉴定

建立了猪乙型脑炎活疫苗基础种子库,对三批基础种子进行了全面鉴定。结果表明,三批猪乙型脑炎基础种子无外源病毒污染,对敏感实验动物小鼠、乳猪和怀孕母猪接种均安全、无异常反应,原代地鼠肾细胞传代至F12代,免疫原性保持稳定、毒力不返强。由此可见,猪乙型脑炎SA14-14-2疫苗株基础种子无外源病毒污染,具有可靠安全性和良好、稳定的免疫原性,可用于疫苗生产,为研制猪乙型脑炎活疫苗打下基础。     

商品化猪丹毒疫苗分类及特点

文章介绍了5种商品化猪丹毒疫苗的种类、毒株组成、抗原含量及相应免疫程序,为了解各种类型的猪丹毒商品化疫苗提供参考。     

Development and evaluation of an enzyme-labeled antibody test for the rapid detection of hog cholera antibodies.

A rapid enzyme-labeled antibody (ELA) microtechnique for the screening of swine for hog cholera antibodies was developed and evaluated with a blind study, using a 640-sample hog cholera serum bank. The total time to run a group of 22 samples was approximately 1 hour. The ELA test results correlated greater than 99% with hog cholera serum-neutralization test results on the same serums. Test results also indicated that the ELA test shares with the hog cholera serum-neutralization test the problem of cross reactions between the antibodies of hog cholera and bovine viral diarrhea.     

Identification of Hog Cholera Viral Antigen by Immunofluorescence. Application as a Diagnostic and Assay Method

In the absence of detectable cytologic changes in hog cholera virus-infected tissue culture cells, hog cholera viral antigen was readily detected by immunofluorescence. The ability to detect hog cholera viral antigen by this method allowed for determination of infectivity titers and also for titration of homologous antibody. Immunofluorescence made possible the identification, in tissue culture, of hog cholera virus from blood, serum, and spleen extracts of experimentally infected swine. Further applications of this method and its limitations are being investigated.     

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