What do you think the cry of the wounded horses represents?

The horses symbolize the death of the innocent. Detering is a farmer. The screaming horses are dying in the fields. Detering laments that the horses are innocent souls. They are beautiful and should not have been involved in the hell that man has brought upon himself. Detering, being a father, has a special place for animals in his heart. Horses are true innocent souls; they do not understand the carnage and pain that is going on around them. Detering would risk his life to find the horse in agony and put him out of his misery.