Female dogs normally come on heat (or in season) around 6-9 months of age and then every 6 months or so depending on breed or size. At this time, they are very attractive to male dogs. Not only will male dogs try very hard to gain access to female dogs (often travelling considerable distances), but female dogs will behave quite differently when in season. This can cause a lot of inconvenience for you and your neighbours and may result in an unwanted pregnancy. To prevent this from happening when your female dog comes into season (or even before), you may want to consider getting your pet neutered, especially if you know you are not going to breed from your dog.
Question by - Deepak Kakar, Mumbai