In adult cats, scruffing triggers fear and stress rather than relaxation. The only time an adult cat is held by the scruff is during mating—if a female in estrus, or “heat”—or when under attack by a predator.

Is it OK to scruff a cat?

The American Association of Feline Practitioners (AAFP) and International Cat Care, as well as many cat-only veterinarians and veterinary behaviorists do not recommend scruffing. Instead, they recommend cat-friendly, low stress, and fear free handling techniques.

Why does Scruffing a cat paralyze them?

It is his instinct to go limp when his mother carries him. ... His mother cat also grab may him by the scruff to get him to stop doing an undesirable behavior, like nipping or biting. This allows mommy to assert her dominance. She'll often groom the kitten after scruffing to calm him down.