ASK THE VET: Should a female pet have a first heat before she is spayed?
Answered by MHS Veterinarian Dr. Michael Redmer, D.V.M.

Q: We recently found a 4-month-old stray kitten.  Friends have advised us to have Fergie sterilized now, but shouldn’t a female pet have a first heat before she is spayed?

A: Unfortunately, this is a common myth that still persists, putting pets at unnecessary risk of assorted health and behavior problems as well as the chance that they will contribute to pet overpopulation.  While pet sterilization at any age is potentially beneficial, the maximum protective health benefits are achieved before your pet reaches sexual maturity.

Early sterilization in female dogs and cats greatly reduces the risk of mammary (breast) cancer, prevents ovarian and uterine cancer, and eliminates the chance of potentially life-threatening infections of the reproductive tract.  Similarly, the sterilization of young male animals prevents testicular cancer as well as greatly reduces the risk of prostate disease.  Young, healthy animals are excellent surgical candidates, resulting in quicker recovery from surgery, less post-operative discomfort and often less cost to the pet guardian.

Numerous behavioral problems can be greatly reduced or eliminated with early sterilization.  Sexually mature animals are hormonally driven to reproduce.  In males, this results in roaming and fights with other animals in competition to breed as well as territorial marking.  This can pose a significant public safety issue in sexually mature male dogs, as statistically, they are five times more likely to bite.  Sexually mature female dogs and cats exhibit physical and behavioral signs of receptiveness to mating known as estrus (a Latin word that translates to a “mad desire”) or being “in heat.”  This condition results in almost continuous vocalization in female cats, and often-messy bloody vaginal discharge in female dogs.

Health and behavior problems aside, numerous animals in heat become pregnant during their first heat cycle, which directly contributes to pet homelessness, abandonment and euthanasia.

Besides providing a loving home, ensuring Fergie is spayed before her first heat cycle is one of the best gifts you can give her. She will be a better companion because her attention will be focused on you rather than on the urge to breed.

Michael Redmer, D.V.M., has been a staff veterinarian at the Michigan Humane Society Berman Center for Animal Care in Westland for more than 10 years.

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