应用自制荧光抗体检测仔猪副伤寒

用兔抗猪伤寒沙门菌抗体自制荧光抗体对仔猪副伤寒进行了实验室诊断。结果表明，用自制荧光抗体在2～3h内即可对仔猪副伤寒做出诊断，比直接镜检的特异性和敏感性均强。     

用自制荧光抗体检测湖羊传染性胸膜肺炎

为实现对湖羊传染性胸肺炎病的准确快速诊断而建立的荧光抗体诊断法,通过利用核酸蛋白检测仪,用G50过滤提取IgG,并用荧光素进行标记,制备出了湖羊传染性胸膜肺炎荧光抗体,同时用培养法、乳胶平板凝集法、间接血凝法对荧光抗体法进行了验证,表明该方法能在较短时间内对湖羊支原体肺炎做出准确诊断,与其他病之间无交叉反应,具有快速、准确、特异性高的特点。     

荧光抗体染色法检测猪瘟的研究

利用荧光抗体技术检测病猪内脏器官可能存在的猪瘟病毒，对猪瘟的早期诊断具有十分重要意义，猪瘟的常规诊断需要4～5天，而该项技术可在半天之内作出判断，既快速又客观、准确，在规模化猪场临床上可得到很多广泛应用。     

用ELISA检测猪链球菌病血清抗体（初报）

以2．5％NaCl浸提猪链球菌荚膜多糖抗原,选用2％明胶作封闭液,4％PEG－PBS为血清稀释液,用ELISA检测猪链球菌病血清抗体,特异性强,比琼扩敏感25-250倍,简便快速,在本病诊断、检疫中有一定实用价值。     

藻红蛋白标记抗鸡IgG荧光抗体的高效制备

藻红蛋白的斯托克位移大,荧光量子产率高,荧光明亮,是一种应用前景广阔的荧光染料.制约藻红蛋白应用的主要因素是分离纯化困难及其成品售价昂贵.通过我们已经建立的藻红蛋白低成本高效制备平台.使其应用于预防兽医学检测成为可能.首次采用适宜摩尔浓度的交联剂SPDP将藻红蛋白与抗鸡IgG抗抗体以摩尔比1:1高效交联,经高效液相色谱法纯化制备出藻红蛋白标记的抗鸡IgG荧光抗抗体.本研究对制备的荧光抗抗体从荧光特性、吸收光谱特性、抗体活性、纯度及稳定性等方面进行了鉴定.结果表明,藻红蛋白标记的抗鸡IgG荧光抗体为电泳纯,荧光明亮,抗体活性高,性质稳定,可用于鸡传染病的间接免疫荧光检测.     

WCA-ELISA检测猪链球菌2型抗体

本试验应用菌体包被间接ELISA分别对70份假定阳性血清和70份假定阴性血清进行1:100、1:200、1:400、1:800稀释检测,利用血清流行病学原理对检测结果进行分析,确定了检测方法的最佳单一稀释度,以及判定阳性血清和阴性血清的OD值。并利用建立的间接ELISA对1997年采集的江苏地区的猪血清进行了检测。试验结果发现在1998年猪链球菌大暴发的前期,阳性率高达48%,尤其是双甸马塘地区,阳性率高达72.4%。     

用间接荧光抗体试验检测猪生殖障碍和呼吸道综合片病毒…

用间接免疫荧光抗体（ＩＦＡ）试验检测了猪血清中抗生殖和呼吸道综合征（ＳＩＲＳ）病毒抗体，４６周龄感染ＳＩＲＳ病毒猪的血清（２头接触感染，１３头实验感染），实验感染猪的在接毒后７天可检出抗体，１１～２１天达高蜂（１：２５６～１：１０２４），在感染前ＩＦＡ为阴性的所有１３头猪，感染后１４～２６天血清均转为阳性（１：６４～≥１：１０２４）。从１５个有ＳＩＲＳ临床病史的猪场收集的３４４份血清中，有２５７份     

用间接荧光抗体试验检测鸡肾型传染性支气管炎抗原的研究

建立检测鸡肾型传染性支气管炎抗原的间接荧光抗体试验（ＩＦＡ）其抗体感染作时间Ｉ抗以５０～６０ｍｉｎ，Ⅱ抗以３０～４０ｍｉｎ最佳。该法具有良好的特异性，可检测出人工感染鸡肾型传染性支气管炎病毒（ＩＢＶ）Ａｕｓｔ－Ｔ，ＨＮ９３０１，ＴＪ９３０１，ＢＪ９３０１毒株后的抗原；对自然发病病例检测结果，阳性符合率高于Ｄｏｔ－ＥＬＩＳＡ和气管环中和试验法。     

An evaluation of indirect immunofluorescence in the serological diagnosis of Nosema cuniculi infection.

An indirect immunofluorescence test for serum antibodies to Nosema cuniculi was evaluated in rabbits by comparison with established histopathological methods of diagnosis. Cell-culture isolation procedures and immunofluorescence and histological techniques designed to detect the parasite in urine or tissues were used to confirm the diagnosis. The serological diagnosis showed excellent correlation with presence of brain lesions characteristic of nosematosis, and N cuniculi were detected in 63 per cent of seropositive rabbits but in no seronegatives. Serum cross-reactivity tests between N cuniculi and Toxoplasma gondii showed that these two protozoa are antigenically distinct. The technique offers a simple, sensitive and reliable procedure for diagnosis of nosematosis in a living animal.     

Use of immunofluorescence technic for the diagnosis of rotavirus infection in the calf

A methodical account is given of possible applications of the immuno-fluorescence technique in the diagnosis of rotavirus infection of calf. The technique has proved suitable for routine checks for both its low input in terms of method and hardware and its potential of diagnostic information. The two latter methods are best applicable under routine conditions to testing of faeces-inoculated cell cultures as well as to the detection of rotavirus from faecal smears and frozen intestinal sections. In investigations on the dynamics of rotavirus development in cell cultures, the first freshly formed virus protein was detected six hours from inoculation. The time of one replication cycle was found to be between 16 and 18 hours, with several replication cycles running consecutively, when it comes to virus strains which have become adapted to the cell cultures concerned.     

Avian reovirus antibody assay by indirect immunofluorescence using plastic microculture plates.

An indirect fluorescent antibody test was developed to detect serum antibody to avian reovirus strain WVU2937. This test employed small multiple well plastic plates (8 x 5.5 cm) which readily fitted into the standard mechanical stage mechanism of an incident light fluorescence microscope. The small wells of the plates required minimal (10 muL) volumes of reagents. In tests on 18 sera in which the indirect fluorescent antibody, agar gel precipitin and plaque reduction methods were compared sera which gave negative results in the agar gel precipitin test were sometimes positive in the indirect fluorescent antibody and plaque reduction test, but indirect fluorescent antibody titers were lower than plaque reduction test titers. No false positive reactions were detected in 46 sera from uninoculated specific pathogen free chicks of up to eight weeks of age.     

Naturally acquired Lawsonia intracellularis infection in pigs studied from weaning to slaughter by indirect immunofluorescence antibody test and polymerase chain reaction on faeces

The course of naturally acquired Lawsonia intracellularis infection was studied in 41 pigs by testing blood and faeces samples collected four to seven times from before weaning to slaughter 5 months old. At slaughter, a sample of ileum was taken for histopathology. In the first sampling when the pigs were 2-4 weeks old maternally derived IgG against L. intracellularis was demonstrated by immunofluorescence antibody test in nine pigs whereas the bacterium was detected by PCR in faeces from six pigs. The maternally derived antibodies did not prevent pigs from becoming infected as seven pigs later on shed and/or were seropositive for L. intracellularis. The lowest prevalence of L. intracellularis was observed in 6-13 weeks old pigs and it seemed as though L. intracellularis in early infected pigs only activates a minor antibody response. At slaughter 66% of the pigs were found positive by immunofluorescence antibody test compared to 24% by immunohistochemistry on ileal samples. Thus, applied at the time of slaughter the antibody test appeared to be a highly sensitive ante-mortem diagnostic tool for identifying L. intracellularis exposed pigs with or without current proliferative enteropathy.     

Use of a monoclonal antibody in the diagnosis of infection by Dermatophilus congolensis

A monoclonal antibody (McAb) to Dermatophilus congolensis was produced from murine hybridoma cultures and purified by affinity chromatography. Species specificity was demonstrated using indirect immunofluorescent staining; the McAb was shown to react with 10 D congolensis isolates but not with 10 Nocardia species isolates, a Rhodococcus and a Streptomyces species isolate. The McAb was used to demonstrate D congolensis in clinical material from confirmed bovine and ovine cases and presumptive equine cases of dermatophilosis by indirect immunofluorescent staining.     

Serological diagnosis of infection with the putative bovine leukemia virus.

We report on an accurate, rapid and inexpensive test for the identification of animals infected with the Bovine C-type virus (BLV). The test involves the detection of serum antibodies to BLV using the immunofluorescent (IF) technique on acetone-fixed, infected cells. The specificity of the test was demonstrated by the fact that virus was found by electron microscopy in 90% of cattle showing positive reactions. In contrast, virus was not found despite extensive examination in antibody negative animals. Thus, the presence of IF antibody is an accurate indicator of current rather than past BLV infection. In order for the IF test to be specific it is of critical importance that the target cells used are infected only with BLV. BLV antibodies can also be detected by the immunoprecipitation (Ouchterlony) technique. However, a significant proportion of BLV infected animals showing positive reactions in the IF test failed to show precipitin antibodies to the virus. Likewise, BLV infection was demonstrated by both the IF test and electron microscopy in many animals with persistently normal levels of blood lymphocytes. Thus, neither the precipitin test nor the blood lymphocyte count (Bendixen's key) can be used to rule out BLV infection.