NORMALIZATION OF REPRODUCTIVE FUNCTION IN GERM-FREE MICE FOLLOWING BACTERIAL-CONTAMINATION

The capacity for reproduction in germfree mice remain inferior to thei r conventional counterparts even after improvement of feed and other s uch rearing conditions. The authors provide evidence of increased repr oductive capacity in germfree mice following association with bacteria . Estrous cycles were normalized in female mice accidentally contamina ted with bacteria, and in mice given fecal suspensions of the accident ally contaminated mice per os. Significant rises were seen in their co pulation and implantation rates, reaching levels comparable to values in conventional mice. In male mice, bacterial contamination induced si gnificant increase in sperm motility. Bacteria were identified in the feces of the contaminated mice, and reproductive capacity was examined in mice associated with the identified bacteria. As a result, normali zation of the estrous cycle, and rises in copulation and implantation rates were noted in B. distasonis and C. perfringens di-associated mic e. Values from B. subtilis mono-associated mice were comparable to tho se in germfree mice. These results from our accidental contamination i ndicate that B. distasonis and C. perfringens are capable of normalizi ng estrous cycles in female germfree mice, and in increasing their rep roductive capacity by raising their rates of copulation and implantati on.