Transmission and Establishment of Streptococcus mutans in an animal experimental system.

S.变形杆菌是人类和实验动物龋病中最重要的致病菌。几项研究表明，大多数人，有或没有龋齿，携带S。变异人然而，S.乳牙萌出前口腔内未检出变形菌。这种感染与S.根据血清学和细菌学的相似性，变形链球菌可能是家族内传播，尤其是来自母亲。从一位母亲和她的孩子身上分离出的变异体。本研究旨在探讨母鼠体内接种量对窝传、龋病发病率及沙门氏菌建立的影响。SPF级雌性大鼠体内携带不同数量的变形链球菌。口腔中的变形链球菌，使怀孕，和S。检查从母鼠到窝仔的变形菌。S.在任何组中，均未从10或15日龄窝仔的下颌骨中回收到变形杆菌MT8148R或6715，然而，在20日龄窝仔中回收到这两种菌株。S.在断奶时，从窝仔和母鼠的下颌骨中恢复了变形菌。此外，窝内患龋率与窝内患龋程度呈正相关。大坝的变形水平。研究了接种量和感染性挑战对S.在SD大鼠和ICR小鼠中检测变形杆菌。用不同接种量的S.变异人一次或十次感染S. 10个挑战的变异株增强了S.与单一感染相比，大鼠或小鼠中的变形杆菌显著增加。S.当动物喂食蔗糖饮食时，变形杆菌增强。

S. mutans has been considered to be most significant pathogen in dental caries of humans and experimentalanimals. Several studies indicated that most people, with or without dental caries, harbor S. mutans. However, S. mutans was not detected in the oral cavity before the eruption of primary teeth. This infection with S. mutans seemed to be of intrafamilial transmission, especially from mother, based on serological and bacteriological similarity of S. mutans isolated from one mother and her children. The purpose of the present study was to investigate the influence of inoculum size in dam to litter transmission, incidence of dental caries and establishment of S. mutans in experimental animals.SPF female rats, which had harbored various number of S. mutans in their oral cavities, were made pregnant, and the transmission of S. mutans from dam to litter was examined. S. mutans MT8148R or 6715 was not recovered from the mandibles of 10 or 15-day old litter in any of the groups, however, both strains were recovered in 20-days old litter. There were positive correlations between the number of S. mutans recovered from the mandibles of litter and those of dam at weaning. Furthermore, positive correlations were shown between the occurrences and severity of caries of litter with S. mutans level of dam. The influence of inoculum size and infectious challenges on the establishment of S. mutans were examined in SD rats and ICR mice. The animals were infected with various inoculum sizes of S. mutans either once or 10 times. Infection of S. mutans with 10 challenges enhanced the establishment of S. mutans markedly in rats or mice, compared with that of one infection. The establishment of S. mutans was enhanced when the animals were fed with sucrose diet.