I think that herd animals can sense, blood by smell. Just like predators. And herd animals, at least some species, will not like that one of their kind leaks blood, because it will atract predators. Also there is a present theory that some bovines, cows, deer etc are color blind. And thats why hunters often can wear high visibilty jackets without fear they will be noticed by game. Then, after the animal is shot, wounded, there is additonally a mixture with smell of whatever additional smell is caused by adrenallin, fear, stress, pain plus the body langaugae of wounded animal itself. The herd will recognise one of their kind in distress, just like predators will recognise the weakest animal in the group and choose that one to attack. 22 lr can be lethal, but will not make too much bleeding. So, my educated guess would go to other senses of herd alerting, not necesserily to visual recognition of blood. Some animals might try to assist other in distress, like possibly elephants living in family groups, some will kick wounded one out of a herd where family bonds are not present.