In medicine, etiology refers to the many factors coming together to cause an illness. It is normally the focus of epidemiological studies. The etiology of scurvy is a good example. With scurvy, sailors going to sea often lacked fresh vegetables.
So, how long are dogs pregnant? The answer varies depending on several factors, but the average length of gestation, aka pregnancy, lasts between 58 to 67 days, with 63 days being the average delivery date.
Male dogs are never to old to breed. Being 11 years old his sperm quality may not be good anymore so she may not get pregnant. Dogs pregnant 60-65 days so just keep an eye on her. You should know for sure in about 3 weeks if she is pregnant or not.