For four days starting Thursday, adult cat adoption fees will be just a third of the usual cost, slashed from $120 to $39. Kitten adoption prices will remain at $195.

The RSPCA says the same care will be paid to matching each animal with the right family as usual.

Chief executive officer Dr Liz Walker said the promotion would not only find new homes for cats, but spread awareness about the need for desexing.

“Cats have very little difficulty conceiving and giving birth, so nearly every undesexed female cat who is exposed to an undesexed male during the warmer months will become pregnant,” Dr Walker said.

“Many people don’t realise that cats can start breeding as young as five months. Some may breed up to five litters through spring, summer and autumn.”

Every cat has been desexed, microchipped and vaccinated.

The RSPCA says it costs around $140 to desex and microchip a male cat, and between $195 and $230 for females.

With $160 for vaccinations, that comes to an average total cost of around $400.

Cats are available for adoption from RSPCA care centres and participating Petbarn stores, including the Kangaroo Flat store.

The promotion runs until Sunday, November 26.

 Those interested in adopting a cat can visit the RSPCA website for more information.