| 【Objective】Streptococcus suis (SS) is an important porcine pathogen and a zoonotic pathogen. Among
various types, Streptococcus suis type 2 (SS2) has the strongest pathogenicity. It can not only cause acute sepsis, meningitis,
arthritis and even death in pigs, but also lead to human infection and death. In order to evaluate the transmission risks of SS in slaughterhouses, the sampling, detection, isolation and identification of SS were carried out in a slaughterhouse
in Dongguan.【Method】The synovial fluid and tonsils of 40 pigs were collected for PCR detection and SS isolation. The
isolated strains were used for morphology, physiology and biochemistry identification, 16S rDNA PCR amplification, typing
PCR detection and antibiotic sensitivity test.【Result】The nucleic acids extracted from the synovial fluid and tonsils of 40
pigs were detected by PCR. In 40 synovial fluids, the positive rate of SS was 22.5%, but no SS2 was detected. In 40 tonsil
samples, the positive rate of SS was 32.5%, in which the positive rate of SS2 was 7.5%. Three strains of SS were isolated from
80 tonsil and synovial fluid samples of 40 pigs. The PCR results showed that one of the three strains was SS type 4, and the
genotype was epf-mrp+gdh+gapdh+fbps-orf2+sly-; while the other two strains were SS type 9, and the genotypes were epfmrp+gdh+gapdh+fbps-orf2+sly-and epf-mrp-gdh+gapdh+fbps-orf2+sly+, respectively. The drug sensitivity test showed that
the three SS strains were resistant to penicillin G, lincomycin, polymyxin B and sulfaisoxazole, and sensitive to enrofloxacin,
ciprofloxacin, spectinomycin and amoxicillin.【Conclusion】The results suggest that there are a large number of recessive
infection of SS in the pigs of the slaughterhouse, and there is a risk of human infection by SS2. |
