非典型猪瘟和隐性猪瘟的诊断和防制

疑某猪场发生非典型猪瘟，采取病死猪的脾、淋巴结，用Ｄｏｔ－ＥＬＩＳＡ法检测猪瘟抗原，结果阳性，诊断为猪瘟。同时用ＳＰＡ－ＥＬＩＳＡ法对猪群开展猪瘟抗体的检测，先后采集７５头份仔猪血样（２０～２８日龄），８５０头份生产母猪血样。检测结果表明，猪瘟抗体水平低于保护值（ＯＤ＜０．３）的仔猪１１头，占抽检仔猪的１４．６％，母猪１０头，占生产母猪的１．１７％。为此对以上低抗体的猪用猪瘟兔化苗再次进行加强免疫接种，经１５天后检测其血清抗体的ＯＤ值，结果仍然没有升高。通过本试验证实，猪瘟低抗体的猪，对免疫的应答能力很差，低抗体的母猪还可能成为猪瘟的隐性感染者，并能垂直传播到下一代，是非典型猪瘟的传染源。淘汰低抗体的母猪，是控制和消灭非典型猪瘟的有效措施。

Diagnosis and Control of Inapparent and Atypical Hog Cholera

Atypical Hog Cholera(HC)was found on a pig farm by detecting the HCV antigen from spleen and lymphaden of dead pigs with Dot ELISA,and antibody to HCV with SPA ELISA.The serum was sampled from 75 piglets and 850 sows.The results showed that 14 6% of the piglets and 1 17% of the sows have antibody titers lower than protection tevel (OD 490 <0 3).After vaccinating these with low antibody titer with HCV vaccine,No increasing of Antibody titer was observed.This indicated that the pigs with low HCV antibody titer have poor immune response to vaccination and might become inapparent infection and transmit vertically the virus to the offspring.It is possible that these porcine are infection source of Atypical swine fever.The experiment suggested that elimination of the sows with low titer antibody is a effective measure to control and eradicate the Atypicaal Hog cholera.