Abstract
As the aged pets are increased, functional pet foods that provide health benefits to control aging and prolong health span will become more desirable. We previously reported that oral administration of Lactococcus lactis H61 has the potential to suppress some of the manifestations（incidence of skin ulcers and hair loss）associated with aging in senescence-accelerated mouse. In this study, the effects of strain H61 on aging level of dog as a pet food. In a placebo-controlled double-blind trial, healthy various kinds of privately-owned dogs（n＝24）were randomly divided in three groups. They were received heat-killed cells of strain H61（109 cfu level/day or 1010 cfu level/day）or not, daily for 4 weeks. Before and at the end of the 4 weeks,blood and feces samples were taken for analysis of blood parameters and putrefactive biomarkers. The questionnaire for aging level was also carried out. As a result, aging level of dogs was not altered in all three groups. Serum analysis showed that some parameters were altered in those groups, but they were within normal range. Immune biomarkers in serum were not substantially altered by administration of strain H61. In a open test, the effect of fermented milk made by only strain H61（H61-fermented milk）on aging level of private-owned dogs was evaluated. Healthy various kinds of dogs（n＝20）received H61-fermented milk（109 ～1010 cfu/day）daily for 6 weeks. Questionnaire survey for aging level of dos was significantly better after this intervention. Oral administration of live strain H61 would provide beneficial effects on aging level of dogs.
