Please help! 12 yo pig's skin is just terrible. His face/eyes/ears are also bad. White skin worse than black. Has been a problem for about 5 years now. Cant figure it out. Starting to cause open sores. Ive tried sun screen, baby oil, diet, bathing, and more. What is causing this? What can i do?

Please help! 12 yo pig's skin is just terrible. His face/eyes/ears are also bad. White skin worse than black. Has been a problem for about 5 years now. Cant figure it out. Starting to cause open sores. Ive tried sun screen, baby oil, diet, bathing, and more. What is causing this? What can i do? oink!