Honestly, I think you're just seeing the post breeding season weight loss normal to bucks. They are so steroided up during the fall that they put on a massive amount of muscle. However, post rut, their body almost stops producing testosterone, hence they quickly lose all that temporary muscle and become very doe-like. Due to the rigors of the rut, as well as the rapid decline in male hormone production, an older buck can lose 25% of his body weight in one month. That's a 200 pound buck only weighing 150 pounds a month later. Into winter, they can lose enough weight that they look one to two years younger than they did in October/November.
