I am trying to find a food suitable for putting weight on a 21 months old dog. Dog is very healthy just need a bit more weight, any suggestions welcomed.

Thank you.

Tripe always works on my skinny juveniles.

Tripe, as said by previous person, raw, green tripe, cant beat it for putting on weight.

Raw green tripe, it's the best !!

Tripe! If you can't get the green stuff then try the bags in the freezers at pets at home. Give him a bowl of that every other day and he'll soon look the part

Thank you :-)

I need to do the same, currently back on a puppy food and also raw breast of lamb, mine is the same age and nothing seems to stick regarding body weight!!

Also worth googling recipes for Satin Balls, I have used them when my bitches have gone slightly anorexic after a season etc
From memory it includes things like oats, eggs, oil, lard, beef mince, molasses. you mix then mould into treat size balls, add a few each day as treats...
I have always found them well tolerated and highly effective at bring weight back as well as green tripe.