Abstract
BACKGROUND: Mastitis is a common complication in lactating women. However, the diversity of intestinal bacteria in infant exclusively fed infectious milk remains uncharacterized. Our colleagues recently established a method based on 16S and 23S rRNA-targeted reverse transcription-quantitative PCR (RT-qPCR) for detecting bacteria. MATERIALS AND METHODS: In the present study, the bacteria present in 14 samples of milk and infant feces were characterized using the RT-qPCR method, and concentrations of fecal organic acids were measured during the period of breast massage using HPLC. RESULTS: Streptococcus agalactiae and Str. parasanguinis were detected in milk from mastitis patients, whereas Str. salivarius and Str. thermophilus were the predominant bacteria in milk from engorged breasts. In feces of breastfed infants, Str. salivarius, Str. thermophiles, and Str. parasanguinis were isolated. Levels of lactate were high in fecal samples, whereas the pH of infant feces stabilized during breast massage. The bacterial diversity of milk from lactation infectious breasts was similar to that in feces of infant fed milk from lactation infectious breasts. Streptococcus species isolated from the feces of breastfed infants are related to oral cavity health. CONCLUSION: These results suggest that Streptococcus species, which are part of the healthy oral microflora, may play an important role in preserving the intestinal bacterial flora in infants fed infectious milk.