Several reproductive diseases can affect male cats. Although most of these disorders (other than cryptorchidism) are rare, the most commonly encountered conditions are discussed below.
Cryptorchidism is a failure of one or both testicles to descend into the scrotum. It is the most common reproductive disorder in male cats. The condition has a genetic basis and can be inherited from either parent. If only one testicle is affected, the cat will still be fertile. Because this is often an inherited condition, cryptorchid cats should not be used for breeding. The undescended testicle is also more likely to develop cancer, so neutering is recommended.
Short-term inflammation of the testes or epididymis may be caused by trauma, infection, or twisting (testicular torsion). Inflammation of the testes and epididymis may also follow infection in other organs. Besides cases due to trauma, these conditions are rare in cats.
Signs are pain and swelling of the testes, epididymides, or scrotum. There may be wounds or other abnormalities in the scrotal skin. The disease is diagnosed by physical examination, ultrasonography, and laboratory tests. Because the condition is painful, sedation or anesthesia may be necessary for diagnosis. Treatment is difficult unless the cause of the inflammation can be identified. The outlook is unknown even with prompt treatment because inflammation can cause permanent damage. Application of cool water packs may decrease testicular damage caused by inflammation. If there is a bacterial infection, antibiotics will be administered. If the cause is an immune disorder, medications that suppress the immune system may be administered but are often unsuccessful and can also cause infertility. When maintaining fertility is not important, castration is a reasonable treatment choice for inflammation of the testes or epididymides due to any cause.
Longterm inflammation of the testis or epididymis may follow short-term inflammation, although in some cases there is no history of testicular inflammation. Tumors may also be present. Other causes of this disease include previous exposure to excessive pressure, heat, cold, or toxic agents. Hormonal causes are also possible. Many animals do not have any signs of the disease except for infertility; however, decrease in size or softening of the testes may be present. The diagnosis and treatment is as described above for the short-term condition. It is unlikely that animals with longterm inflammation will regain their fertility.
The inability to completely retract the penis into the preputial cavity (paraphimosis) can occur after erection. It is seen most often after breeding. The most common cause of paraphimosis in cats is a band of hair that entangles the penis. Paraphimosis is a medical emergency because the exposed penis quickly becomes swollen (due to accumulation of fluid), dry, and painful. If recognized early, before severe swelling and pain develop, paraphimosis is easily treated. Treatment consists of trimming the hair, gentle cleansing, and lubrication of the exposed penis. The penis is replaced inside the prepuce and the swelling resolves once circulation is restored. Sedation or anesthesia may be necessary. Some advanced cases require surgery to replace the penis back within the prepuce. If the urethra is damaged, a urinary catheter may be temporarily necessary.
Priapism is a persistent erection that is not due to sexual stimulation. It is diagnosed by physical examination. Partial paraphimosis can also result. Priapism can be caused by neurologic dysfunction, drugs, blood vessel abnormalities, masses on the penis, trauma, or an unknown cause. If blood circulation is blocked, it is a medical emergency. Some medications may help, but neutering does not. If the damage is severe, amputation of the penis may be necessary.
Phimosis can be due to an abnormally small preputial opening, resulting in the inability to extrude the penis. It may be present at birth or acquired as a result of trauma, inflammation, or a bacterial infection. The signs are variable. Usually, the problem is unnoticed until the cat attempts to mate and is unable to copulate. Diagnosis is established by physical examination of the prepuce and penis. Treatment depends upon the severity of the phimosis and the intended use of the cat. If the cat is not to be used for breeding, treatment probably is not needed, although neutering should be considered to prevent arousal.
The prostate gland is located within the pelvis and behind the bladder. The prostate gland is not required for sperm production, but it is important for successful breeding. The prostate gland provides the major part of the fluid in the ejaculate and is important in nourishing the sperm cells and increasing their movement. Prostatic diseases are not common in cats.
Hormonal enlargement of the prostate is called benign prostatic hyperplasia. Inflammation of the prostate is called prostatitis and is usually due to bacterial infection. Abscesses (pockets of infection), cysts, and tumors can also occur within the prostate. These disorders cause enlargement of the prostate gland and can cause straining when defecating, blood in the urine, repeated urinary tract infections, and pain. Additional signs, such as fever, malaise, poor appetite, stiffness, and pain in the belly, are often due to bacterial infections or tumors. Prostatic diseases are diagnosed by physical examination, rectal examination, x-rays, ultrasonography, and blood and semen tests. Treatment and outlook vary depending on the type of disorder.
Also see professional content regarding reproductive diseases of the male small animal.