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.
Canine pregnancy lasts for approximately 63 days, but ranges from 57 to 72 days from a single breeding. This is due to the variability in the ovulation timing and semen survival in the female dog. During this time hormonal and physical changes develop and are observed in the female.