Isolation And Identification Of Streptococcus Group D From Goats In Shanghai

Streptococcosis is caused by streptococcus in animals throughout the world. It is susceptible to many livestocks. For example, Streptococcus suis serotype 2, can lead death to human beings. In recent years, The morbidity and mortality of streptococcal disease is rising in our country, and a number of viral diseases following the onset. It decreased the livestock production and lead to great economic losses in China.With the rapid development of sheep industry in recent years, sheep streptococcus appear much and much.It mainly caused by the hemolytic streptococcus that make sheep septic acute febrile disease.They usually characterized fibered pleuropneumonia or meningitis.Few cases characterized arthritis .They always presented with generalized hemorrhagic septicemia and pneumonia and often coinfection with other pathogens.The high morbidity and mortality is harmful to the sheep industry.In early 2009, the goats from a farm in Shanghai showed some signs with high fever, sepsis and swelling throat. The primary diagnosis is that the goats infected by streptococcus by necropsy and microscopic examination. Then samples were collectted for bacterial culture and 15 strains of streptococcus were isolated from the diseased goats, according to the morphology, cultural characteristics, biochemical characteristics and pathogenicity characteristics.To further identify the serotype of the streptococcus isolated from the diseased goats, The streptococcus was tesed by VITEK-32 automatic analyzer, the results showed that this strain belong to Streptococcus group D (Enterococcus faecalis) , while most sheep streptococcus disease is caused by streptococcus group C-- hemolytic streptococcus. In this work, the isolated streptococcus is a Gram-positive bacteria with capsule, and a characteristic ofαhemolytic and short chain. Moreover, the streptococcus group D was confirmed by PCR and gene sequencing. The enterococcus faecalis were determined by the detection of virulence genes of cylA. This is first isolated virulent streptococcus group D in Shanghai to our knowledge.