Epidemiological Investigation And Drug Resistance Detection Of Streptococcus Suis Type 2 In Tianjin Area

Streptococcus suis type 2 is a serious pathogen of swine streptococcosis.Infected pigs most often appear as lymph abscess,meningitis,arthritis,septicemia and so on.Importantly,it can also cause the relevant employees serious infection and death.To survey the infection and prevalence of SS2 in pig farms in Tianjin city,the pig nasal secretions and serum samples from pig farms were collected.Firstly,the serum was investigated by SS2 antibody ELISA.The corresponding nasal secretions of the positive samples were further identified by bacteriological identification,biochemical identification and PCR identification of SS2.Finally,the susceptibility test of SS2 was carried out to reveal the current Tianjin pig Streptococcus type 2 epidemic and drug resistance.For the microbiological identification of pathogens,18 colonies were isolated from 480 samples in 10 pig farm and individuals of Tianjin city.Streptococcus suis type 2 was determined by cultural character,dyeing characteristics,microscopic examination and biochemical test.And the results of drug susceptibility test of anti-Gram-positive bacteriais shown as follow: 18 strains of bacteria were 100%resistant to gentamicin,cefotaxime,ciprofloxacin,ceftriaxone sodium,levofloxacin,and enoxacin.17 strains of bacteria were resistant to doxycycline and amikacin,and 9strains of bacteria were resistant to dysentery.All 18 strains of bacteria were multidrug-resistant,among this 7 strains were Nine heavy resistance,and 11 strains were eight heavy resistance.The results of drug sensitive tests suggest that the drug resistance of SS2 is severe,especially to gentamicin,cefotaxime,Ciprofloxacin,ceftriaxone sodium,ofloxacin,enrofloxacin.In addition,The research provides a reference for the rational use of antibiotics in the case of SS2 resistance.In other words,the rational use of sensitive sulfonamides,Chloramphenicol and macrocyclic lactones antibiotics for treatment under the guidance of the veterinarians not only can effectively prevent swine disease but also reduce the risk of emergence of drug-resistant strains.