What's Everyone Hunting.

[Double Naught Spy]

If the bullet crossed through the brain from side to side (unlike Gifford's wound that stayed in the left hemisphere), then the animal may have had surviving life function because the brain stem got missed, but the animal was brain dead and life function was very temporary. The kicking (disinhibition of the motor neurons) is typical of significant upper CNS insult and while often assumed to be a sign of death, not not diagnostic of death. Another shot would not have been putting the animal out of its misery, but then again, nothing wrong with making doubly sure the animal is dead. I will often check for blink reflex (touching an eye with the end of my shooting sticks or the muzzle of my rifle) to assess whether or not the animal is brain dead. The blink reflex is involuntary and will happen even with unconscious animals, but not those that are dead.

Here, scale might be of consideration. A peccary's brain is about 1/8-1/10th. A 40 cal bullet going through a peccary's brain will do volumetrically more damage than a smaller 9mm bullet going through a human brain along the same path. Again, the first shot was likely just fine, but nothing wrong with a 2nd shot just to be sure the animal does not suffer. After all, you often do not know just how good the first shot was until you do some sort of assessment like the blink test, or the animal gets up and tries to run away, or until you skin it for a closer look.