Correlation Analysis In Parts Of Sichuan Province Boar Semen Case Of Classical Swine Fever Virus Infected With Swine Fever Antibodies

Classical swine fever is due to a classical swine fever virus infectious disease caused by porcine reproductive characteristics of the disorder, piglet mortality and subclinical infection in swine industry in our country, is one of the most serious infectious disease damage, the number of pigs in China die each year because of various disease and total pig number roughly8%-10%ratio, in which all these dead pigs, with up to1/3～2/3of classical swine fever virus infection and death.CSFV can not only horizontal transmission, but also through the boar semen and placental vertical transmission,compared with developed countries, modern genetic breeding in China is relatively backward, tend to the introduction of high-quality boar semen from abroad directly to improved breeds,but through the introduction of quality evaluation of boar semen, semen sources unable to boar health, if boars apparently healthy but carry classical swine fever virus or semen with toxic condition, very easy to cause the classical swine fever virus by semen transmission, from lead to diffusion and popular classical swine fever epidemic, which may be caused by the size of farms swine plague it is difficult to control.A pair of specific primers of this study can be designed according to the GENEBANK E amplified CSFV E2gene sequences of5genes of Sichuan Province, a number of areas for67samples of boar semen were detected by RT-PCR, and collected the67boar serum ELISA antibody detection, in order to provide reference data for prevention and control of Sichuan Province reproductive and respiratory syndrome. The main results are as follows:1). In the67boar semen samples, from not detected from the four areas of Qionglai, Leshan, Meishan, Pujiang4CSFV positive semen, the detection rate was5.9%, at the same time, the4strains of CSFV wild strains were named as QL-1, MS-1, LS-1, PJ-1.2). In semen collection also collected boar serum, detection kit using IDEXX of classical swine fever virus HerdChek antibodies were detected in all serum of swine fever antibody. Among them, the positive rate of CSFV antibody was highest in the pig farm in Mianyang, reached100%, more consistent antibody titer, antibody blocking rate variation coefficient of only9.2%, showing a good immune status;While several suspected the incidence of swine (Qionglai, Suining, Meishan, Leshan, Pujiang) CSFV antibody level in serum positive rate of pervasive boar is not high (respectively62.5%,83.3%,58.3%,60%,80%), on the uniformity of the antibodies, antibody level uneven, large variations among individuals, block32.7%,22.3%,31%,33.4%,27.5%reach the rate coefficients of variation were.3). Using DNAstar software MegAlin, compare the E2gene sequences obtained from the research of QL-1, MS-1, LS-1, PJ-1of4strains of CSFV semen samples amplified E5gene sequence with the domestic and foreign representative strains,the results show,97.8%homology in the nucleotide sequence of E24strain CSFV obtained in the E2nucleotide sequence of CSFV in the study of (PJ-1and QL-1) and-99.9%(LS-1and MS-1), showed high homology, compared with the results of the representative strains, and from Taiwan AF352565the low homology, in93.5%(PJ-1)-93.9%(QL-1),the high homology with AF09244from Wuhan, in97.8%(PJ-1)-99.9%(LS-1); compared with the results of foreign strains, the amplified E2gene sequence coding for4and Japan’s D49533has high homology (respectively:LS-1:95.2%, MS-1:95.0%, PJ-1:95.1%, QL-1:95.1%), from the United States of America and the AY578687homology is low (respectively:LS-1:91.7%, MS-1:91.6%, PJ-1:91.9%, QL-1:91.4%).4). In order to better understand the genetic variation of Sichuan region of CSFV and explore the source and evolution relationship of Sichuan epidemic strains and reference strains, the application of DNAStar software in the MegAlign on the QL-1, MS-1, LS-1, PJ-1E2gene sequencing amplified4semen samples of amino acid residues order with many domestic and foreign strains of CSFV are analyzed, and the establishment of phylogenetic tree.The results show that, from an evolutionary tree, amino acid sequence of the amplified QL-1, MS-1, LS-1, PJ-1, LS-1and MS-1in the same small branches, and QL-1and Wuhan the most homologous to AF09244, the closest relationship,PJ-1with the number of lines in a large branches, these4strains with the AF333000(Beijing), AF352565(Taiwan), AF531433(Jilin), AY526732(Taiwan), EU497410(Harbin), HQ380231(Guangdong) distantly related sequences.