The Streptococci of Equines.

The research article describes a study on the presence of different types of streptococci in eastern and western horses, its locations, and its impact on the health of the animals.

Study Methodology

• The researchers studied thirty eastern and twenty-three western horses to explore the presence of streptococci, a type of bacteria.
• The regions of focus during the examination included the lower nasal mucosa and the pharynx of the horses.

Findings from Eastern Horses

• The nasal mucosa of eight eastern horses carried non-hemolytic streptococci, a bacteria type that does not break red blood cells.
• Similarly, the researchers could culture these non-hemolytic streptococci from the pharynx of six horses.
• The throats of eighteen horses, however, contained hemolytic streptococci—a type that breaks red blood cells.
• Interestingly, the nasal mucosa of the eastern horses did not show any presence of hemolytic streptococci.

Findings from Western Horses

• Eight western horses had non-hemolytic streptococci in their nasal passage, while the same number also carried hemolytic types.
• Out of twenty-two strains isolated from the pharynx, eleven were found to be hemolytic.

Characteristics of the Bacteria

• Among all non-hemolytic nasal strains, those capable of fermenting a sugar called mannite were predominant.
• Non-hemolytic types from the pharynx may or may not ferment another sugar called lactose, but all do ferment raffinose or inulin—two other types of sugars.
• None of the non-hemolytic types were found to be pathogenic for mice, unlike hemolytic strains from the nasal mucosa of western horses, which were pathogenic for both mice and rabbits.
• These hemolytic strains were found to be of the Streptococcus pyogenes type, a bacteria responsible for various types of infections.

Streptococci from Pathological Sources

• All sources with pathological conditions were found to have hemolytic streptococci, which fell into two groups.
• The Streptococcus pyogenes group produced acid in several substances like dextrose, lactose, saccharose, maltose, milk, and salicin, but they did not change the reaction of broth containing raffinose, inulin, or mannite.
• The smaller group, Streptococcus equi, was unable to ferment lactose or acidulate milk, differentiating it from the larger group.

Pathogenicity of the Streptococci

• Both types (Streptococcus pyogenes and Streptococcus equi) were pathogenic for mice, with rabbits being usually more resistant.
• Streptococcus pyogenes was isolated from eighteen out of twenty-two cases of influenza, three out of six cases of strangles, and eight out of nine abscesses in horses.
• Streptococcus equi was found in four horses suffering from influenza and five others affected with strangles, as well as in an abscess and associated with both rhinitis and pharyngitis.