Nine cats and dogs who are massively overweight are about to embark upon a six-month diet and exercise challenge.

The latest batch of recruits have been signed up to the PDSA Pet Fit Club, with the winner receiving a year’s supply of healthy food and an animal-friendly holiday.

The national competition sees each pet receive a plan tailored to their individual needs.

It has been running for 14 years and has helped more than 100 pets lose over 75 stone since 2005.

Among the contestants this year is seven-year-old Alfie, a Labrador from Liverpool who is nearly double his ideal weight at 9st 7lb.

Alfie is one of the dogs taking part in PDSA's Pet Fit Club competition
Alfie weighs almost double what he should (PDSA/PA)

Alfie’s opponents include Bonnie, a spaniel from Blackpool whose penchant for sausage rolls has left her 7.7kg overweight, while Sox, a large cat from Gateshead, once got stuck in a child’s safety gate due to her size.

The pets will receive free weight management food from the SPECIFIC range during the competition, and will be overseen by the vet team at their local PDSA Pet Hospital.

Bonnie from Blackpool is on a diet to slim down
Bonnie’s love of sausage rolls has seen her balloon (Julian Brown/PDSA/PA)

PDSA vet Rebecca Ashman said Pet Fit Club is “a great example of what can be achieved if owners are dedicated and determined to help their pets live a healthier lifestyle”.

She added: “If owners are worried about their pet’s weight they should seek advice from their vet or vet nurse, who can also make sure pets are on the right type of diet, are being fed the correct amount, and recommend ways to increase exercise levels.”

Sox the cat is attempting to lose weight with PDSA
Sox is another of the pets needing to reduce their waistlines (PDSA)

Last year’s winners Borris and Sadie – both dogs – lost 25% of their body weight during the competition.