Lol you're not the first to have technical problems and probably not the last! :)
Now, I don't know much about this... But like smrobs said you should have his testosterone levels tested. In dogs, you can purchase shots to give them that lower test. levels, maybe you can with horses?
Every great dream begins with a dreamer. Always remember, you have within you the strength, the patience, and the passion to reach for the stars to change the world. ~Harriet Tubman