1. Separate the cats. This is the most effective way to prevent any unwanted mating attempts. Keep the male cat in a separate room or crate when the female cat is in heat.
2. Provide plenty of enrichment for the male cat. This will help to keep him stimulated and prevent him from becoming bored and frustrated. Some good enrichment options include interactive toys, puzzle feeders, and climbing structures.
3. Redirect the male cat's attention. If he starts to show interest in the female cat, try to redirect his attention with a toy or treat.
4. Talk to your veterinarian. If you are concerned about your neutered male cat's behavior, talk to your veterinarian. They can provide you with additional advice and support.
It is important to remember that neutered male cats are not able to mate, so there is no risk of pregnancy. However, they can still cause stress and anxiety for female cats in heat, so it is best to keep them separated during this time.