University of Pennsylvania logo A latest study says that female mouse companionship can possibly increase the reproductive life of a male mouse by about 20 percent. This study was conducted by the University of Pennsylvania School of Veterinary Medicine.

The study investigators presume that female presence may influence the spermatogonial stem cells in the endocrine and nervous system of the males. They assume that other systems may also be involved. These state that these findings may aid in the maintenance of male fertility in wildlife as well as in human populations.

For the study, the investigators housed some male mice with female mice; while some male mice were housed without any female mice for a period of about 16-32 months. Each of the male mice was housed with two new female mice at two months interval to evaluate its capability to impregnate the female mice. It was noticed that after the age of 32 months, with an increase in their age, there was a decrease in male fertility in the mice housed with females. This fertility ratio was six months more than the mice housed alone.

Co-author of the study, Ralph Brinster, professor of physiology at Penn Veterinary, says that, “It appears that housing females with a male mouse delays the decline of reproductive processes at the cellular level by somehow affecting the cells surrounding the stem cells that produce spermatozoa in the testes. Whether this female influence occurs in other species is not known.”

It is known that increasing age brings with it a decrease in male fertility; however the factors that delay aging are not yet known. It’s stated that abnormal spermatogenesis was noticed in the lonely mice sooner than it occurred in the mice housed with females. This hints that maybe the sooner damage in the spermatogenesis could account for the earlier decrease in fertility in the lonely mice. The study authors state that females can be credited for the modification of various physiological and psychological responses in the males.

Their study findings are published online in the Biology of Reproduction journal.