Why Does My Dog Have Swollen Testicles?

If your dog's testicles have become swollen or enlarged it means they are exhibiting orchitis, the general term for testicular inflammation. We may also see canine epididymitis if the tube which allows sperm to enter (the epididymis) is swollen and the testicles swell as a result. These are symptoms of an underlying cause. The following are some of the most common causes of swollen dog testicles:

• Trauma: when bacteria enters a wound on the testicles, it can become infected and inflamed. Color changes may occur such as being red around the infection site or seeing purulent discharge. The cause of the wound is varied and could be trauma from hitting against something, the result of a fight with another dog or even a burn or frostbite. Even an ingrown hair can lead to testicular inflammation. It's crucial to monitor any changes and seek veterinary advice promptly.
• Blood or urine infection: the bacteria which causes infection doesn't necessarily have to enter externally. If the dog has a urine or blood infection, bacteria can enter the testicles and result in swelling. This type of infection can spread rapidly and cause further complications if not treated efficiently.
• Contact dermatitis: as with any part of their external skin, if the dog's testicles come in contact with an irritant, it can result in swelling. This can be a plant toxic to dogs, a cleaning product or any other irritating substance which can result in inflammation. Identifying and removing the irritant is crucial.
• Atopic dermatitis: if the dog has a sensitivity to a particular allergen, they can have an allergic skin reaction which also causes swelling. Regular allergy tests and a controlled environment can help manage this condition.
• Testicular torsion: as they hang down from the body, the dog's testicles are often vulnerable. If they get caught or twisted for any reason, it can result in testicular torsion whereby the connective tissue of the testicles is twisted to a harmful degree. It is relatively uncommon, but can result in orchitis or epididymitis. Immediate veterinary intervention is required to prevent severe damage.
• Viral or fungal infection: although less common than bacterial infections, it is possible that pathogens such as fungi or viruses can lead to testicular swelling. These infections often require specific treatments tailored to the type of pathogen involved.
• Parasites: if an external parasite bites or inserts themselves into the dog's scrotum, it can result in parasitosis. Testicular swelling is one possible symptom of this condition. Preventive measures such as regular deworming can help keep parasites at bay.

Infection will occur leading to inflamed and red testicles. From this initial infection, bacteria can travel to different parts of the body. In particular, it can spread through the spermatic cord. For this reason, it is very important we diagnose and treat the cause of a dog's swollen testicles as soon as possible. This helps prevent further systemic infections.