Advice for older dog

[DW]

It's been such a long time since I contributed to this forum and I hesitate in posting about my current 'problem' as though it's not necessarily an A.I. problem, it is relating to a dog that has been prone to Colitis episodes and I know this topic has been covered in the past (sometimes due to side effects?)
Briefly, Jazz is 13.  Has undergone two cruciate ops in the past 12 months and has been doing incredibly well but ever increasing effects of arthritis are causing a concern.    We used Metacam post op and then stopped it but a hiccup about two months ago meant we needed pain relief and he was put on a maintenance dose again.   He had remained on it, as both Vet and I felt some pain relief was needed - as he was getting a little stiff.  A few weeks ago, I noticed that his stools were getting a little darker and rightly or wrongly I decided to stop the Metacam - still giving half a Tramadol at bedtime.
A chat with the Vet last week, had led to us trying pardale V - giving lower than the prescribed dose (two a.m.  and two p.m.) whilst continuing with half a Tramadol at bedtime.   He has been fine on the Tramadol BTW>
He has been on the Pardale for 5 days now but the past two days it has been hard work getting him to eat his full amount of food.  He eats but leaves about a third and he is what I'd describe as a 'reluctant' eater - taking a long time.  He is currenty being fed his staple Royal Canin Sensitivity but I have been successful in mixing in a small amount of a new food I use called Greendog - which he loves.   Thought about changing him over completely to this but when we get to the 75% sub stage, it seems to trigger a tummy upset.   The same applies to Lily's tinned food (Fish) - he will pick this out of his food when I add it but again, he can't be fed this entirely for the same reason.
I am happy to provide completely home cooked but worry about nutrients.
Any advice on (a) Pain remedies for arthritic dogs  and (b) food would be gratefully received.
Also, has anyone heard of Galiprant being used on dogs?
He also has homeopathic tabet Arnica/Rhus etc.    He has two types of Joint Aid (Ymove/Synoquin and sometimes Joint Aid).
Many thanks

[Jo CIMDA]

Hi DW

I hadn't heard of Galiprant but I did look it up and it might be worth a try. 

Also, people swear by CBD oil.  Have you considered that?

As for his food, I would give 50/50 and that way Jazz is getting the best of both without an upset tummy.

Jo