I am not sure where to ask this question in the forum. This seemed like the only place. I have a 16 year old Quarter Horse that has grown a very long shaggy coat for the past 3 years. He has been tested 3 times for Cushings with negative results. It does shed out in the spring. A few have suggested it could be his genetics and not to worry. Easily said than done. I was wondering how I can track his family history and maybe somehow see if there is that problem in his lines. I know I am probably grasping at straws but just thought it was worth a try. Thanks for any input. He shows no other signs of Cushings disease.