Summarize this article in one sentence.
Your pug needs to have a pleasant and enjoyable temperament. The pug you plan to breed with yours should also be well behaved and even tempered. This will ensure their puppies will be good, strong pets. If your dog has any emotional or temperament issues, you should rethink breeding him or her. You only want to breed the best pugs you can. Before you breed your pug, you need to have him tested to determine his genetic background. This will test your dog’s bloodline to ensure there are only good qualities in his or her bloodline. If your pug is a registered as a purebred, you can obtain your dog’s bloodline from the American Kennel Club or other registering authority. You need to be sure your pug and the pug you are planning to breed with are not directly related in order to prevent any possible genetic defects caused by inbreeding. Your pug should be in fine physical shape in order to be bred. This means your pug should be free from any genetic health problems that could be passed down from him or her to the puppies. Take your pug to the veterinarian to get checked out. Common pug diseases that would deter you from breeding your pug include:  Luxating patellas, also known as 'wobbly kneecaps', which is the excess movement of the kneecap sideways that can cause the hind leg to lock in an extended position. Hip dysplasia, which is when the hips are poorly formed so they do not move smoothly in the hip joint, causing the the dog to have a weak back end and lead to early arthritis Entropion, which is an inwards turning of the eyelids where the hairs rub on the surface of the eye and cause constant irritation Hemivertebra, which is a malformation of the spine bones that causes a physical deformity of the spine Cleft palate, which is a separation of the palate of the mouth area, often corrected by surgery at a young age Before your pug is mated or bred, you need to ensure he or she is up to date on all necessary vaccinations. This is especially important for your female pug because most vaccines cannot be given during pregnancy.  Your pug must have the immunity provided by vaccination so she can pass some of these antibodies on to her puppies via her milk, which will give the puppies a low level of protection at a time when their immune systems are weak and developing. She should also be up to date with all her parasite treatments as well, including everything from heartworm to roundworms. All these things are also important for female pugs because pregnancy suppresses the immune system. This means that any parasite could take advantage of her weakened immunity and breed, which could impact her health and as well as the unborn puppies. Your pug should be at a healthy weight in order to be healthy enough to breed. To check your pug’s weight, run your fingers along his or her rib cage. With a gently pressure, you should be able to easily feel the ribs with no rolls of fat in the way. Your pug should also have a defined waistline if you look from the side and above. However, there should be enough fat cover that the bones of the hips and pelvis do not stick through. When deciding to breed your female pug, you should make sure she is at least 18 months old. This means she should have gone through at least three heat cycles, which will allow her the right amount of time to fully grow and mature. This will make sure that she can handle the rigors of pregnancy and giving birth.   The male pug should be around 12 to 15 months, since this is how long it would take him to reach full sexual maturity.  Female pugs should not be bred if they are older than six years old. By this age, she is approaching the dog equivalent of retirement age, which means that the strain of pregnancy could cause organ damage. Also, as a general rule, once your pug is bred, she should not have another litters within the following season, so make sure to give her a break in between. Female pugs should also not have more than four litters during her life. If you don’t have both a female and male pug, you can find your pug a stud, or breed-ready male dog, through different sources. You can buying the services of a male pug, find another local breeder, or find an owner willing to help you out. Make sure you ask to see the male pug’s pedigree and see if he is registered with the Kennel Club, which will allow the puppies to be registered as purebred.  The Kennel Club does not keep a register of stud dogs, so any information you retain about the male pug has to be done on your own. Make sure you meet the male pug before you agree to breeding to ensure that he has a good temperament and physical appearance.

Summary:
Watch your pug’s temperament. Verify your pug’s genes. Examine your pug’s health. Check your pug’s vaccination status. Evaluate your pug’s weight. Consider your pug’s age. Pick the right male pug.