When your fighting boss monsters and the get low on stamina, They will begin to drool and then look for food. If you have meat placed on the ground they will sometimes go and eat the meat and then whatever status effect that meat has will be inflicted(with diminished returns). Note that not all monsters are carnivores and they will never eat the meat regardless(Diablos eats Cactus, Barroth eats bugs, etc). Deviljho is the easiest to get to eat your meats as he gets hungry every few minutes.
Adding onto that, repeated meats won't work, they will just make it easier to inflict the status. (1st time a monster eats tinged meat, he or she will be paralyzed. 2nd time, nothing happens unless that monster has been hit with a paralyzing weapon)