Studies On Streptococcus Suis Pathogeny Isolates Biology Characteristics And DNAfingerprinting Analysis

Streptococcus suis infections have risen gradually to become one of the major disease problems in the pork industry. Hollander, Jansen(1951) and England, Field(1954) reported streptococcus suis infections. Elliott (1966) and Windsor (1975) isolated streptococcus suis from porket sapraemia, meningitis and arthritis. Later, this disease was reported in Europe, Australia, Brail and Far East. In China, Wu shuoxian first found the sporadic case of streptococcus suis infections from Shanghai countryside. In 1970's, the incidence of a disease increased and intended to be more serious in the late 1980's, which broke out in many places. Streptococcus suis infections appeared and infected to death in Sichuan, 6,2005. So far, 13 provinces have reported streptococcus suis infections, which infected and caused a big damage in the South area, Southwest and East area. Streptococcus suis infections is one of the disease which has feazed Chinese pork industry and have threatened the health of the employed related to this industry. We study 20 strains which were isolated from the infective pigs, using the method of Randomly amplified polymorphic DNA(RAPD) to develop a segregant genotype, account the distance between the strains in order to pick out the representative strains. Here is the main points:Twenty strains were isolated from the infective pigs in the parts of provinces from2003-2004. They were identified as group D, C and G.using the method of Randomly amplified polymorphic DNA(RAPD) to prepare the polyvalent inactivated vaccine against S. suis disease.With the result of RAPD, the heredity distance of 20 strains is 0.041-0.727 and average number is 0.293. The distance between 9th and 12th...