Ferret ideal weight: benchmarks, seasons and a set of scales

The MSD Veterinary Manual gives these benchmarks. Build varies from one ferret to another: your vet can tell you whether yours is at a healthy weight.

Entire male

Up to about 2 kg.

Neutered male

1.2 kg on average.

Entire female

Up to about 1.2 kg.

Spayed female

0.8 kg on average.

Ferrets reach adult size at around 5 to 6 months and are considered adult at one year.

According to the PDSA, it is normal for a ferret to gain weight before winter, to build up reserves, and to lose it in spring. Their coat changes too: thicker and darker in winter, it moults in spring and autumn.

What should concern you is weight that climbs in the middle of summer, or winter weight that doesn’t come off in spring: cut back on treats and talk to your vet.

• Kitchen scales accurate to the gram work well: put a basket or box on them, reset to zero, then place your ferret inside.
• Weigh at the same time of day, for example once a month, and note each result.
• Compare with the same season the year before, rather than with the previous month.
• Weight is also used to dose treatments: a recent weight helps avoid a dosing error.

Obesity is one of the common health problems in ferrets, according to the Royal Veterinary College (RVC). A ferret that eats too much and doesn’t burn enough energy gains weight.

• Limit treats, and avoid sugary ones.
• Let your ferret out of the cage for at least 2 to 4 hours a day, supervised or in a ferret-proofed space, as the MSD manual recommends.
• Offer toys, tunnels and hiding places that encourage exploring.

Outside the spring weight loss, a ferret that is getting thinner should be examined. Weight loss is among the signs of two common diseases in adult ferrets: adrenal gland disease, often with hair loss that starts at the tail, and insulinoma, a tumour of the pancreas that can also cause weakness and dragging back legs.

Log each weigh-in in MyArk: the weight tracker shows everyone in the household whether changes from one season to the next stay normal, and the latest weight is to hand for dosing a treatment.

• A weight chart for each pet, over several years
• A weighing reminder, for example every month
• Treats logged by everyone in the household
• An up-to-date weight for dosing treatments