Ferret neutering: a health decision, especially for females

Ferrets reach puberty between 4 and 8 months, in the first spring after their birth. According to the Royal Veterinary College (RVC), females come into season as the days lengthen, from March to September, and stay in season until they are mated or the days shorten. A swollen vulva is the most visible sign.

Entire males have a strong musky smell during the breeding season and mark their territory with urine.

During a prolonged season, oestrogen levels stay high. According to the RVC and the British Small Animal Veterinary Association (BSAVA), these hormones can stop the bone marrow making blood cells: this is hyperoestrogenism, which can lead to severe anaemia and death.

Surgical spaying

Removal of the ovaries and uterus. It ends seasons and the risk of anaemia, and clearly reduces the smell. According to the BSAVA, it is best done outside a season, when the risk of bleeding is higher.

Hormone implant

A small implant, barely bigger than a microchip, placed under the skin. According to the BSAVA, it stops seasons for about a year and a half to two years, sometimes longer depending on the implant. Placed in a female that has already been in season for a long time, it can prolong the season at first: your vet will take this into account.

Vasectomised male

Mating with a sterile male ends the season, but it has to be repeated every season; it can cause injuries, stress and false pregnancy.

There are also one-off hormone treatments to end a current season: these are for your vet to decide, who will then suggest a long-term solution.

Castration

Removal of the testicles. It reduces the smell and can reduce aggression; a castrated male no longer tries to mate.

Hormone implant

According to the RVC, it reduces the smell 5 to 14 weeks after it is placed, and its effects last up to about 16 months. Keep the male away from females in season for the first few weeks.

Vasectomy

The male can no longer father kits, but keeps his smell, behaviour and aggression. It is mainly used to end females’ seasons.

Adrenal gland disease is common in adult ferrets. Its most common signs are hair loss that starts at the tail and lower back, itching, a swollen vulva in a spayed female and, in males, a return of sexual behaviour or difficulty passing urine.

Several veterinary sources link this disease with surgical neutering: after the ovaries or testicles are removed, other hormones keep stimulating the adrenal glands. According to the MSD Veterinary Manual, the age at neutering no longer seems to play a major role, and still-preliminary data suggest that a hormone implant might reduce this risk. For this reason, the PDSA recommends an implant rather than surgery, while other sources present both options.

Record the neutering or the implant, with its date, in your ferret’s MyArk health record: a reminder alerts everyone in the household before it is time to talk to the vet about it again.

• The date of the neutering or implant in the health record
• A reminder before the renewal date your vet suggests
• Dated observations: seasons, hair loss, swollen vulva
• Weights on a chart, to show your vet