Reproductive aging in female birds.

Birds are underutilized as animal models for studying the basis of longevity, cellular adaptations for resisting oxidative damage, and delayed reproductive senescence. Reproductive aging patterns in female birds range from slightly slower than those in rodents of similar size to extremely slow or even negligible. The best-studied laboratory bird model of female reproductive aging is the relatively short-lived, rapidly aging domestic laying hen. Promising long-lived avian models for the prolongation of fertility include cage birds, like the budgerigar, and wild seabirds, like the Common Tern, many of which show no reproductive aging in nature. Preliminary comparisons of ovarian aging patterns in Japanese quail and budgerigars suggest that declining stores of primary oocytes may play different roles in fertility declines in these two species, as they do among mammals.