[3] The alpha-hemolytic bacteria are ones that exhibit a partial hemolysis with green coloration when grown on sheep blood agar[4] (see image.)

Streptococcus ferus was originally isolated from the oral cavity wild rats who were living in sugar cane fields and eating a high sucrose diet [5] The species name ferus, meaning wild, refers to their association with these animals.

Streptococcus ferus are gram positive lanceolate coccobacillus[1] Non-motile and approximately 0.5 micrometers in diameter.

[6] They are non-sporulating and catalase-negative[1] The majority of specimens test positive for the production of acetoin (Vogues-Proskauer reaction).

[5] Streptococcus ferus is commensal in wild rats and pigs and demonstrates a relatively weak cariogenic potential compared to other streptococcus species such as S. mutans[7] S. ferus has not had any reported pathogenic instances in humans.