MGS V: The Phantom Pain - Where to find D-Dog, It's Special Abilities and How to use it on field

The Phantom Pain will continue the complex saga of the Snake soldier line, connecting storylines from Metal Gear Solid: Peace Walker, Metal Gear Solid: Ground Zeroes, and the rest of the Metal Gear timeline. During the Battle, you can select a buddy which can help you during the attack. Here is how to find and train the D-Dog in Metal Gear Solid V: The Phantom Pain.

D-Dog is a wolf-cub companion in Metal Gear Solid V: The Phantom Pain. He is very useful during the mission, especially when you are using the stealth approach.  

How to Find D-Dog?
In the wild during your travels, in a forest after his mother is killed by poachers. When you try to ignore him, he’ll follow you around. He'll cry out loud enough that you can’t just sneak without him by your side. As he grows up he'll become ready for action. You’ll notice D-Dog has an eye patch(just like Big Boss) and you look closely while he’s was a puppy, you’ll see he’s missing an eye.

Update:

You will find him in Afghanistan, in the farthest south of the map - north of Spugmay by the side of a road. .

What are D-Dog's Special Abilities?
As you approach near an enemy camp, D-Dog will start marking the people in the camp(Hostile and Alias) within his radius even for the people/enemy out of sight. He can also mark wild animals and plants in the desert. On the enemy camp, you can order him to bark so that he can grab some attention of enemies within range. You can order D-Dog to wait, hide and to bark till you sneak into the camp.

There is also a command called 'Keep Em Busy', where D-Dog will attack the select enemy. He is unable to kill the enemy, but it's just used to distract and draw some attention nearby.

Hint: You can deal with a couple of enemies without raising an alert.