Investigation of presence of α haemolytic streptococci, enterococci and streptococci-like bacteria in different materials originating from pigs

摘要

The aim of this investigation was to establish the presence and prevalence of streptococci, enterococci and streptococci-like bacteria in various materials originating from healthy, slaughtered and dead pigs belonging to different categories from several farms and slaughterhouses in the Republic of Serbia. The total number of investigated samples comprised 226 swabs of tonsils and noses from clinically healthy breeders, swabs of tonsils from piglets 5-20 days old, parts of nasopharyngeal tonsils from breeders slaughtered in a slaughterhouse, parts of nasopharyngeal tonsils from piglets slaughtered in a slaughterhouse, swabs of slaughtered pig carcasses from a slaughterhouse, swabs from knives for evisceration in a slaughterhouse, as well as swabs of lungs, abdominal cavity and organs from piglets which died suddenly. The standard microbiological methods were used for investigations of the presence of the listed microorganisms. Commercial biochemical tests were used for the identification of the isolated bacteria and specific sera for capsular antigenes were used for serological determination of the isolated S. suis strains. It was established that the great majority of the isolated strains belonged to the genus Streptococcus (36) (75%), and the minority of the strains belonged to the following genera: Enterococcus (6) (10.4%), Aerococcus (3) (6.2%), Lactococcus (2) (4.2%) and Globicatella (2) (4.2%). The great majority of Streptococcus species belonged to S. suis. The presence of other á haemolytic streptococci was established in the swabs of nasopharyngeal tonsils: Streptococcus sanguinis (13.8%), Streptococcus salivarius (5.6%), Streptococcus mitis (5.6%), Streptococcus parasanguinis (2.7%) and Streptococcus oralis (2.7%). Also, S. bovis was isolated in a smaller percentage (5.6%). The greatest number of isolated bacteria from the genus Enterococcus belonged to Enterococcus faecalis (80%), while the minority of isolated strains belonged to Enterococcus faecium (20%). The following from the streptococci-like bacteria were isolated: Aerococcus viridans, Globicatella sanguinis and Lactococcus lactis ssp.cremoris.