Microbiological characteristics and antibiotic resistance of field isolates Streptococcus suis

Abstract

Streptococcus suis is an important associated pathogen with a wide range of diseases in pigs such as meningitis, septicemia, pneumonia, endocarditis and arthritis. S suis can be transmitted to humans through direct contact with a sick animal. The disease of pigs with streptococcus not only causes significant direct damage, but also contributes to the spread of viral infections such as PRRS, which is registered in 80% of cases on farms affected by streptococcus. In recent years, there has been a significant increase in the prevalence of streptococcal infections, as well as their role as a complicating factor in viral and bacterial diseases. An important factor in the spread of this disease is the irrational use of antibiotics of different groups, which contributes to the rapid acquisition of polyresistance of pathogenic microflora. The article presents the results of studies on the microbiological characteristics and antibiotic resistance of isolates of Streptococcus suis isolated from pathological material from sick pigs. In order to better and faster isolation of the pathogen, the features of its damage to organs and tissues and its localization in the body of piglets were studied. Epizootological monitoring of streptococcal outbreaks on pig farms in Ukraine was carried out. The farms on the basis of which the sampling was carried out are permanently unfavorable for streptococcus of piglets. Laboratory studies of S. suis field isolates found that all studied microorganisms fermented arginine, salicin, glycogen, D-glucose, sucrose, galactose, maltose, salicin, trehalose, inulin, with positive reactions to α-galactosidase, β-glucutane and β-glucura . Of the isolated Str. suis isolates, 87% were sensitive to erythromycin, 75% to clindamycin and 55% to cephalexin, 43% of isolates were resistant to gentamicin and 20% to enrofloxacin. It was found that in 25% of cases S. suis caused the disease in the form of acute monoinfection, in 20% of cases S. suis isolated E. coli, in 16% of cases - with Pasteurella multocida, in 11% of cases - with Haemophilus parasuis. Mixed infection was observed in 17% of cases. Key words: Streptococcus suis, antibiotic resistance, culture properties, diagnostic methods.