A greyhound is the second fastest land mammal accelerator next to the cheetah. It can reach speeds of 45 mile per hours on the racetrack and zero as very happy couch potatoes in retirement on your couch. It is not a high-energy dog, but it can gallop very quickly due to its unique physical characteristics.
The greyhound has a larger heart and set of lungs than other dogs. This allows it to circulate more blood and oxygen through its system when racing. The stride is often referred to as a double suspension gallop when racing. This is because the dog's paws hit the ground twice for every cycle of steps it takes. The spine is very flexible, allowing the dog to lurch and jump quite high too. This is ideal for the starting gate.
About 25,000 race dogs are retired every year. The dogs can live up to twelve years or more (some up to 14 years) and are one of the most long-lived big dogs around. However, their racing careers span a measly two to four years of age before they are retired.
The dog is very aerodynamic due to the thin fur coat it has. It is a shorthaired dog with a very thin skin that can be easily ruptured. This is the reason the dog is often muzzled in races, and not due to any aggression as most people think. The dogs are actually one of the most non-aggressive breeds around and prefer to hide than to confront a stranger.
The dog's thin skin means that it is highly susceptible to environmental poisons and medications. They can be toxic to the dog, even when the medication is a dog flea medication. The paws also can absorb lawn chemicals, which can kill it, so it should be kept off of any grass that has been treated.
The dog is more like a cat than a ferocious guard dog. Despite its size, it will sleep upside down on your couch and want to be close to its owners at all times. It does suffer from separation anxiety, particularly if it is a race dog. They are not used to being without other people or dogs around. It will collect small items to keep for itself and these can include your children's toys, the remote control, or any food left out on the counter. The dog is so quiet and graceful, you may not even notice when it takes off with these things.
A retired greyhound can make an ideal housedog. The bark has been bred out of the dog so it is usually very quiet. It loves to hang around the couch and be a part of a family, despite a career as a race dog. It easily adapts to its new life of leisure but does need to be walked several times a day.