Lascivious Neutered Cat


Why? Fix it!
What do you do about a cat acting out sexually? We’ve had Sebastian “Basti”, 20 months old, for a year. He was neutered at 8 months. He’s very sweet but recently he has started humping my bedding, my clothes, and he attempts to hump me. He bites the object on its surrogate neck and does pelvic thrusts and butt flutters. Frankly, it’s off-putting. Basti gets along with our other 2 cats. They climb trees and play in our large yard.

Dr. Nichol:
Butt flutters, eh? Ahem. A delicate subject indeed, although not for Basti. He is not shy about his amorous proclivities, possibly related to testosterone levels normally not seen in neutered cats. His brain is driven by his hormones. Don’t feel bad. It happens even in the best families.

Testosterone is produced in the testicles. Neutering removes these reproductive organs. But despite having had this procedure, Basti may still be secreting this male hormone somewhere else – internally. With his aberrant behavior affecting his relationship with you, I advise finding the source and getting it corrected.

All male fetuses start life with two testicles but both of Basti’s may not have found their way to his scrotum by the time he was neutered. An “undescended” testicle, remaining inside his abdomen, would produce enough testosterone to trigger his unwanted advances. Having this sex hormone measured with a blood test would be a good start. An abdominal ultrasound could then show the location of a retained testicle or some other source of testosterone. Surgical removal would be best but I’d start by asking the veterinarian who neutered this young stud if two normal testicles were removed during surgery.

A prescription medication called cyproheptadine can reduce testosterone production, making it a pretty good diagnostic tool. Following a course of this oral treatment Basti may actually start behaving like a gentleman. You’ll still need a definitive diagnosis. Your veterinarian can set about locating the problem and removing it. Basti needs to get past his primal urges and stop that infernal butt fluttering.
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Dr. Jeff Nichol is a residency-trained veterinary behaviorist. He provides consultations in-person and in groups by Zoom (505-792-5131). Each week he shares a blog and a Facebook Live video to help bring out the best in pets and their people. Sign up at no charge at Post pet behavioral or physical questions on or by US Post to 4000 Montgomery Blvd. NE, Albuq, NM 87109.