If you don’t want to breed with your female ferret, you have to have it spayed. Because the female ferret, as the female ferret is also called, would otherwise go into a life-threatening perpetual heat.
During estrus or mating, i.e. the time when the female is ready to mate, the ovaries produce a lot of estrogens, a female sex hormone. Estrogen causes the female’s eggs to mature and prepares the uterus for conception.
It also causes the female vulva to swell, signaling the male ferret that the female is ready to mate. After mating, which triggers ovulation, the ovaries produce little estrogen and a lot of progesterone, the pregnancy-protecting hormone. However, if there is no mating and therefore no ovulation, the female remains in heat. She goes into a perpetual heat and the production of estrogen continues at full speed.
Anemia caused by estrogen
When estrogen circulates in high doses in the ferret’s body for a long time, it has deleterious effects. It attacks the blood stem cells in the bone marrow. All new blood cells are created from these stem cells. In a healthy animal, the new blood cells replace the old ones that have perished as a result of natural cell aging. So too much estrogen ultimately leads to anemia because dead blood cells are not replaced by new ones. 20 to 30 percent of all unneutered and uncovered ewes become ill from the excess of estrogen.
Heat makes you sick
Ferrets with “estrogen poisoning” develop pale mucous membranes, become weak, and often lose weight dramatically. The condition of the animals is critical and sometimes the wyvern cannot be helped and dies within two to five days. Therefore, all females that are not used for breeding should be castrated. During spraying, the vet removes the ovaries and thus the organs that produce estrogen. The castration of the female is not only used for contraception, but also for health protection.