Why can't unneutered adult male cats be kept together?
It is not recommended to keep unneutered adult male cats together. This is because male cats in heat will exhibit territorial behavior due to hormonal changes, leading to fights, injuries, and constant noise. Unless the cats are kept separately, it's not recommended to keep them together. It's also advisable to have the male cat spayed/neutered after he/she goes into heat to prevent future fights. 
Benefits of neutering male cats
1. It can reduce the occurrence of diseases. Due to differences in physiological structure, cats may develop many diseases due to estrus and reproduction.2. Spayed/neutered cats will not contract sexually transmitted diseases, such as feline AIDS (a feline immune system disease).
3. Spaying/neutering can prevent cats from running away and getting lost when they are in heat.
4. It helps cats recover from the stress, irritability, and loss of appetite caused by being in heat, allowing them to regain their original lively nature. It also helps male cats break the habit of using other methods to release stress.
5. Avoid indiscriminate breeding, control the number of stray cats, and improve the quality of the environment.
Precautions for neutering male cats
Generally, the ideal time for a cat to be spayed or neutered is after its first heat cycle, when its reproductive organs are fully developed and the surgery is most suitable. Performing the surgery too early can easily lead to other diseases in the cat.Surgery should be avoided as much as possible for cats in heat, because during this time, the cat's reproductive system is congested with blood, and surgery at this time can easily cause massive bleeding. This is especially true for the more complex procedure of neutering female cats, which should be strictly avoided.
