Some biological characteristics of Streptococcus suis isolated from pigs in Ha Noi

Abstract

Specimens of 360 pigs from the households, farm breeding areas and industrial farms in Dong Anh, Hoai Duc and Phu Xuyen district in Ha Noi were collected for this study. The studied results showed that the pigs in Ha Noi infected with Streptococcus suis with the average infection rate was 26.11%; in which the rate of the healthy pigs carrying S. suis was 22.22% and the pigs having respiratory disease symptoms was 30.00%. The infection rate of the fattening pigs was 36.66%, higher than that of the sows (23.33%) and the piglets under 2 months old (18.33%). The rate of the healthy pigs infected with S. suis bacteria in the households was 28.33%, this rate for the pigs raising in the farm breeding areas was 20.00% and in the industrial farms was 18.33%. The pigs suffering from respiratory disease in the households infected with S. suis bacteria (35.00%) were higher than those in the farm breeding areas (28.33%) and in the industrial farms (26.66%). The rate of the isolated S. suis bacteria carrying virulent arcA gene accounted for the highest rate (59.57%), followed by mrp gene (13.83%), epf gene (9.57%) and sly gene (5.32%). The S. suis isolates in this study were highly sensitive with antibiotics, with the corresponding rate, such as: amikacin (89.36%), florfenicol (87.23%), ceftiofur (86.17%), amoxicillin (82.97%), ampicillin (72.34%); meanwhile, they showed high resistance to erythromycin, colistin, neomycin, with the rate: 81.91%, 76.59% and 73.40%, respectively.