雏番鸭细小病毒病诊断技术和试剂的研究

Studies on Diagnostic Techniques and Reagents of Muscovy Duckling Parvovirusis

根据番鸭细小病毒单克隆抗体（ＭＰＶ－ＭｃＡｂ）致敏的胶乳可与ＭＰＶ产生特异性凝集反应，而这种特异性凝集反应可被ＭＰＶ抗体所抑制的原理，建立了胶乳凝集试验（ＬＰＡ）和胶乳凝集抑制试验（ＬＰＡＩ）。致敏抗体蛋白浓度为０．５ｇ／Ｌ时，ＬＰＡ可检测出ＭＰＶ最小蛋白量为２μｇ／Ｌ。对ＬＰＡ与ＦＡ、ＬＰＡＩ与ＡＧＰ作了比较，结果：ＬＰＡ阳性率９０．５％，ＦＡ阳性率９２．４％，两者的符合率９２．４％；鸭血清ＬＰＡＩ抗体效价在Ｌｏｇ２５以下时，ＡＧＰ试验均阴性，前者比后者敏感性高３２～６４倍。ＬＰＡＩ抗体效价与保护力相关性试验结果表明，当鸭血清中ＬＰＡＩ抗体效价在Ｌｏｇ２１以上时，雏番鸭均能耐受强毒的攻击，两者呈正相关。致敏胶乳和抗原保存时间在４～８℃时，分别为５个月和６个月；在２２～２８℃时，分别为７ｄ和１５ｄ。

Both a latex particle agglutination (LPA) and a latex particle agglutination inhibition test (LPAI) were developed based on the reactivity of polyadelic latex particle conjugated with MPV McAb to the MPV, and its blocking by the MPV McAb and anti MPV serum. When the conjugative MPV McAb was at 0.5 g/L, the detectable MPV antigen amount was as low as 2 μg/L by the LPA. Comparison of LPA to fluoresent antibody test (FA) and LPAI to agar gel precipitation test (AGP), the results showed that positive rate of LPA was 90.5%, FA positive rate was 92.4%, and their concordance rate was 92.4%. When the antibody titers of LPAI in duck serum were below log2 5, AGP was negative. The sensitivity of LPAI was 32 to 64 fold than that of AGP. All muscovy duckling were protected from MPV challenged when the antibody titers of LPAI were at log2 1 or over in serum of muscovy duckling. The antibody titer of LPAI and the protective rate were closely related. The store period of the conjugative polyadelic latex particle and MPV antigen were 150 days and 180 days at 2 8℃, 7 days and 15 days at 22 28℃, respectively.