Boar with swollen hock joints

[Ranchy]

We have a year old Duroc boar who's not getting around very well. Both, but especially the right, hock are swollen on the inside of the joint, and he seems to be in a lot of pain at times. At other times, the swelling is still present, but he gets around just fine.

Does anyone know what might have caused this, or what it is, and what, if anything, can be done about it?

Thanks in advance!

[Ranchy]

Thank you! I'll pass that along to my hubby, and we'll see about getting some of that. Do you have to get it from a vet, or can you purchase it at a feed store?

"Rastus" pretty well has the run of three pens and the whole alleyway between pens, along with "Rosie", our sow. They are just dirt, with tin sheds built over them, so I don't think it's caused from being on cement. We got him at a sale last spring (4-30), he came here from Texas, and I have no idea what they had him on before. This problem only occured recently, though, so I'm thinking it probably wasn't caused by anything that long ago.

We just really don't want to pass it on to other generations. I'm really hoping it's not hereditary.