In order to get a grasp on what type of image I wanted I looked at many different animal cruelty campaigns. One that was really helpful was an article on bored panda which showed several different campaigns to do with abuse. These were extremely helpful when coming up with my concepts.
These inspired me to do the shadow in my photo as it was something that was subtle but powerful which is very similar to the photos below. Each have a strong message, and convey them effectively without making the image complicated.