Both are mostly genetics. Next time, pic an animal whose 'parents' dont have fat in the neck and lacking in the hind quarters. You can sweat the fat off of his neck by using a neck sweat that you can buy at most livestock show suppliers (sullivans) And about the only thing that would help his hind quarters is good feed and plenty of exercise. I know some people recomend ramps, but I am not knowledgeble on the proper use, so I dont do that, but it is an option.