A contribution towards diagnosis and virulence of Streptococcus suis in swine [electronic resource].

Includes references.

A survey to detect Streptococcus suis (S. suis) serotype 2 in 75 weaned pigs were examined at the time of slaughter from EI- Basatin Abattoir. 150 swab specimens of the nasal cavity and tonsils of pigs were obtained for bacteriologic culture, Streptococcus suis serotype ,2 was detected by I using brain heart infusion agar containing a Streptococcus selective supplement and 5% goat antiserum raised against serotype 2. The precipitation zone diameter (PZD) on a quantitative hasis led to -the proposal of a simple and reliable technique to screen swine herds for S. suis serotype 2 in weaned pigs. The organism was found in both sites in nasal and tonsils specimens with a percentage of 41.33 and 60%, respectively, of all S. suis serotype 2 isolated. In order to study host - specific of virulence of Streptococcus suis types for mice and pigs, it was found that when a group of mice was inculated intraperitoneally with 10' CFUlml of 13 different S. suis serotype 2 appeartd that the S. suis strains that I were highly virulent for pigs caused high morbidity (100%) and an intermediate mortality (20-60%) in mice, the Streptococcus suis strains that were weakly virulent for pigs caused high morhidity (40%) but low mortality (0%) and the strains that were non- virulent for pigs, induced highest morhidity aud mortality (100%) in mice. Streptococcus suis serotype 2 was more commonly isolated from pigs older than 4 week. Most isolates were suscept}ble td Amoxicillin + Clavulanate, Ampicillin, Ceftiofur, Enrofoxacin, Penicillin; Spectinomycin, Spiramycin, Tiamulin and Trimethoprin + Sulphadiazine. A high frequency (30%) of resistance to tetracycline w.as observed. Among isolates of serotype 2, 9.7%) were resistant to Lincomycin and 12.9 % to Spiramycin.

Summary in Arabic.

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