| The Classical Swine Fever is one kind of contagious infectious disease caused by CSFV which may be divided into acute, sub acute, chronic and non-typical hog cholera. In 1984 the Office International des Epizooties listed hog cholera as one of the A kind 16 legal infectious diseases because it caused huge economic loss. This kind of disease will exist in our country for a long time, with the character of high frequency, large and increasing affected area and local spreading to all quarter. The usual clinical symptom is reproduction barrier, namely the newborn pig morbidity, the death and produce still-birth, the silent infection and the long-enduring infection case assume the trend of escalation. The increasing immunity defeat phenomenon and the more chaotic immunization schedule have seriously hindered our country pig-breeding industry. Therefore, this thesis makes a research on the CSF immunity resistant level of pig farms using biological activity filler, CSFV infection situation as well as the promotion of immunization procedure.1. Investigation of immune antibody of the CSF and the CSFV infection situation in certain parts of hogsDuring the period from April to October in 2007, the author examined the 420 blood serums from Changsha 10 biological activity filler pig farm using ELISA reagent box produced by IDEXX Corporation and got the result as following: there is only one farm whose average CSF immune body seropositive rate is over 80%,3 farms is below 70%, Among the pigs in 10 subjects, the average CSF immune body seropositive rate of all pigs except those younger than 3-weeks is below 70%.When examining the serums which have extremely high or low immune antibody using RT-PCR method, the author found that 9 among 40 samples had been infected by CSFV.2. Research on the CSF immunization procedure of pig farms using biological activity fillerThe research shows that the sow CSF vaccine of more dosage (2 shares or 4 shares) are much better .The sows which was inoculated 2 or 4shares against CSFV 14 day antenatal, their seropositive are respectively 100% and 95%, the seropositive rate of furrows produced after 30 days is 90% , which might protect the furrows from CSF; while lessening the dosage to1 share, the seropositive rate decreased to 70%,and the seropositive rate of furrows produced after 30 days is 40% , so the immunity protection effect is bad. Besides, we may see that the sows have great influence on the immune body of furrows. For growth/fattening pigs, it is better to inoculate firstly when they are 30-day old and secondly when 60-day old. Of course the exact day on when the furrows immunization is monitored by the result and does not have a fixed pattern. After the standard of CSF vaccine being increased according to the statement No .913 issued by Ministry of Agriculture, three vaccines chosen in this research have good effect on pigs and without any distinguish difference. In addition, the research also shows that the sty no matter it use biological activity filler or clement as ground, it has no difference on the immune antibody and immune effect of CSF.
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