No you don't, when the time is right in the females heat cycle, he will do it instinctively.
Most probably because it wants to mate.
Any dog can mate with another breed of dog.
Please give more detail to your question. What do you mean by when a dog fights over mate. However a dog will fight over another dog until one dog is hurt or the mate chooses.
No, it would have to mate with another dog.
Train your dog to attack if it smells another person on your mate.
Labradors have puppies when they reach maturity and mate with another dog.
you go to the pound and buy a girl or boy dog to mate with your first dog
Weird question, Well they mate with each other but I'm not telling you that they mate with the same sex! You need both male and female to mate and they form a puppy, the puppy grows up and repeats the cycle.
Dogs put their head on another dog's neck as a sign of dominance or affection. It can also be a way for them to show trust and seek comfort from the other dog.
A female dog that has been spayed won't allow a male dog to mount her, and if she did would not get pregnant. Most of the time though, once spayed they no longer put out the signal to male dogs that they are receptive to being mated, so the males don't even attempt to mate with them.
The size dog should be like a Chihuahua 13in and 36centimeters or to be sure another Yorkie just in case
tell the dog/cat to mate with another pet :P