2016 Volume 19 Issue 1 Pages 8-14
The effects of daily administration of Streptococcus salivarius K12（SSK12）on mouth odor and oral bacteria were investigated in beagles. Beagles given SSK12（SSK12 group n＝3）tablets and those given no SSK12（control group n＝3）were subjected to organoleptic tests of oral gas odor and expired gas odor and measurement of oral ammonia, methylamine, methylmercaptan, and hydrogen sulfide by using a gas detector meter. Oral swabs were cultured anaerobically for bacteriologic examination and were also used for detection of Porphiromonas (P) gingivalis and P. gulae by using a direct PCR method and a PCR method using black pigment-producing bacteria. Oral bacterial count was determined using real-time PCR. Organoleptic tests revealed a decrease in the assessment score of oral gas odor and an increase in the distance at which expired gas odor was detectable in beagles given SSK12. In comparison with the baseline level, the ammonia concentration decreased in the SSK12 group after 4 weeks of administration, whereas the corresponding concentration increased in the control group at 4 weeks. The concentration of methylamine significantly increased（p＜0.05）after 4 weeks in comparison with the baseline value in the control group, but there was no significant change in the SSK12 group. Oral swabs and black pigment-producing bacteria showed no presence of P. gingivalis and there were no distinct changes in the oral bacterial count. These findings suggest that SSK12 can be expected to exert a mouth odor-suppressing effect in dogs. However, further investigation is required for evaluating the effect of SSK12 on oral bacteria.