My 10 year old Border has arthritis. He has gone from being a very active dog and full of spark to al of a sudden not being able to move fast at all and seems to have lost his mojo. Any suggestions? He has just had xrays which reveal compression in a few discs in his spine and spurs. I hate seeing him hot be able to move as quick as he could and chase the birds, would love some advice please. Apart from his arthritis is health is A+.