A couple of thoughts-

First off regarding raw salmon. Killed my first Britt at 4 years of age. Got sick the week before opening day for uplands and was pointing grouse just a few weeks before. $3000.00 and two weeks later I was told I could pick him up on Monday. Sunday night he hemorrhaged so instead of picking him up on Monday we euthinized him. Pretty sure I can't recommend the "let them get really sick and treat them" plan.

Never heard of a lab that doesn't readily take to swimming. Britts, albeit game, are really lousy swimmers. A couple of tricks are to tie a pheasant wing around a bumper and as a normal part of training toss it into the water occasionly. My experiance is that they get so wigged out over the pheasant wing that they are swimming after it before they realize what the heck they're doing. Or you can do what I did and simply cross the river and continue fishing. They'll follow in due time