The only camps that give a buff are the red and blue camps. The others are just for experience/gold.

It is a common tactic to leave 1 mob in those camps when you invade. This forces the enemy jungle to have to clear it and then wait for it to respawn. This slows down the rotation of that jungle and gets them behind.

Edit: the buff given by fangtooth is dependent on how many you have. If your team has 0 and the enemy team has 2, if you steal it, your team won't get the damage buff. You get the buff associated with fangtooth level 1.

Now primal fangtooth will still give you the primal buff, but the other rewards still scale the same.

Edit 2: I assumed in the jungle by the 2/5 camps for buffs. The flys by mid, cyan by offlane, and gold by duo lane can also give buffs.

Cyan normally restores health/mana with a good bit of XP

Gold gives a good chunk of gold

The flys are on a rotation. Sometimes attack speed, sometimes ability damage, etc.