[paula.m.moore]

5 months is the most difficult time to have boy pigs. It's puberty and they have to establish dominance.

A bigger cage should help them. They need space. For boys (based on my experience) I would recommend at least a 2x5, but a 2x4 would be much, much better than the 2x3.

I would also separate them with cage grids so they are sharing the same cage and are able to see/smell/hear each other. Otherwise I think it's like introducing them all over again every time you try and get them together.