Bloodhound

The bloodhound is a large scent hound originally bred for hunting deer and wild boar, but also used from the Middle Ages onwards for tracking human beings, and now most often bred specifically for that purpose. Thought to be descended from hounds once kept at the Abbey of St Hubert in Belgium, it is known to French speakers as the Chien de Saint-Hubert.

This dog is famed for its ability to discern human odors even days later, over great distances, even across water. Its extraordinarily keensense of smell is combined with a strong and tenacious tracking instinct, producing the ideal scent hound, and it is used by police and law enforcement all over the world to track escaped prisoners, missing people, lost children and lost pets.

Weight	Male	46–54 kg (101–119 lb)
	Female	40–48 kg (88–106 lb)
Height	Male	64–72 cm (25–28 in)
	Female	58–66 cm (23–26 in)
Coat	short and dense.
Colour	black and tan; liver and tan; red
Life span	7-8 years

source : wikipedia