Much like humans, canines are afflicted with a vast number of diseases that span infections (viral, fungal and bacterial), skeletal and muscular disorders, cardiovascular and circulatory diseases, nervous system ailments, cancers, endocrine diseases, gastrointestinal diseases and urinary and reproductive system illnesses.

In canines, viral infections include rabies (hydrophobia), canine parvovirus, canine coronavirus, canine distemper, canine influenza, infectious canine hepatitis. lyme disease, leptospirosis, brucellosis and kennel cough are some common bacterial infections affecting dogs. Some canine fungal infections are blastomycosis, histoplasmosis, ringworm and sporotrichosis. hookworm, tapeworm, roundworm, ticks and fleas are parasites that commonly plague dogs.

Skeletal and muscular disorders include osteoarthritis, hip dysplasia, luxating patella, spondylosis, and panosteitis. Cardiovascular and circulatory diseases include heart disease, heart defects, platelet disorders and hemolytic anemia. Epilepsy and different kinds of paralysis are nervous system ailments that commonly affect dogs. Most dogs are affected with ear infections during their lifetime and may develop cataract or go deaf in old age. Skin ailments, where dogs lose fur and itch are also very common. There are a large number of different cancers and tumors that affect the skin and organs in them. Diabetes, thyroid, Addison's disease, and Cushing's syndrome, are some endocrine diseases that affect canines.

The list of diseases that afflict canines is a long one. However, listed below are some of the more serious ailments.

Cancer
Cancer is one of the leading causes of death in canines. Cancer is a disease that occurs when the normal control genes in a cell fails and that cell divides relentlessly. Dogs are afflicted with lymphoma, fibrosarcoma, melanomas, leukemias and plasmacytomas amongst several other cancers. Early warning signs of cancer include abnormal swellings that persist or grow, sores that do not heal, weight loss, loss of appetite, bleeding or discharge from any body opening, offensive odor, difficulty in eating or swallowing, hesitation in exercising and being active or loss of stamina, persistent lameness or stiffness, difficulty in breathing, urinating, or defecation. Surgery offers a solution if the cancer is localized to a single area and can be completely removed. Chemotherapy and radiation are the other choices for treatment of cancer.

Kidney disease
The kidneys are biological filters that clear the blood of harmful toxins. A dog's kidneys may be damaged due to many reasons such as poison, aging, infection, trauma, cancer, auto-immune diseases, and genetic predisposition. Kidney failure can be acute, where a sudden loss of function takes place that may not be reversible or chronic. An irreversible loss of function occurs gradually over months or years. The symptoms of chronic kidney disease are frequent urination, increased thirst, weight loss, fatigue and weakness. Blood and urine tests are usually performed to diagnose kidney diseases. While medication is used for treatment, diet too plays an important role in recovery.

Arthritis
Canine arthritis is a common disease amongst dogs, especially the large built ones. Older dogs may suffer from it, but it is also seen in puppies due to development disorders. Obesity increases the likelihood of the onset of this ailment. Canine arthritis is the inflammation of joints due to infectious, metabolic, or constitutional causes. Dogs who suffer from it experience pain in the joints, and have difficulty in movement. The signs to watch out for are when a dog is reluctant to exercise, has difficulty in moving, limps, or even struggles to stand up from a laying position. There are many different medicines used to treat canine arthritis, any of which may be prescribed by a vet. Natural cures, vaccines and surgery are the other treatment options. It is a painful ailment, and can be treated best when diagnosed at an early stage .

To watch one's pet suffer from an illness is an unfortunate reality that has to be faced with often. The best one can do to ensure that their pet has a long and healthy life is to provide them a healthy and nutritious diet, regular exercise, good hygiene, vaccinations and regular visits to the vet, and also plenty of love.