Final answer:
Arthritis is one of the most common debilitating diseases in older animals. It involves inflammation of the joint, causing joint pain, swelling, stiffness, and reduced mobility. There are various forms of arthritis caused by different factors.
Step-by-step explanation:
One of the most common debilitating diseases in older animals is arthritis. Arthritis is a common disorder of synovial joints that involves inflammation of the joint, resulting in joint pain, swelling, stiffness, and reduced joint mobility. There are more than 100 different forms of arthritis, and it can arise from aging, damage to the articular cartilage, autoimmune diseases, bacterial or viral infections, or genetic causes.