Isolation of Treponerna hyodysenteriae from Porcine Feces and Drug Sensitivity

Abstract

In April and October, 1981, attempts were made to isolate Treponema hyodysenteriae from 147 swine fecal samples collected on 74 farms in 31 prefectures. As a result, T. hyodysenteriae was isolated from 57 samples (38.8%) from 35 farms in 19 prefectures. When classified by the district, T. hyodysenteriae was mostly isolated in samples from Kyushu. When classified by age, T. hyodysenteriae was found in samples about 5 or 6 manths after inoculation. When classified by the type of feces, T. hyodysenteriae was not isolated from normal or soft feces, but from semisolid and watery feces. The number of T. hyodysenteriae organisms isolated was larger in watery feces with occult blood than in any other type of feces.
On the other hand, β weakly-hemolytic Treponema was isolated from 6 samples (4.1%) collected on 4 farms.
The in vitro sensitivity test was conducted on 90 strains of T. hyodysenteriae (obtained from 57 samples) and 6 strains of β weakly-hemolytic Treponema, with the DJ70 strain as a control, to 4 compounds, carbadox, olaquindox, tiamulin, and tylosin. As a result, all the strains of T. hyodysenteriae, including the control, exhibited marked sensitivity to carbadox and high sensitivity to olaquindox and tiamulin, but showed two-peaked sensitivity to Tylosin. Besides, β weakly-hemolytic Treponema exhibited the same sensitivity pattern as T. hyodysenteriae, except that it had no strains resistant to Tylosin.