Canned salmon uses salt to help preserve the meat which makes it one of its downsides.
Salmon canned in a can contains a high level of sodium as compared with salmon fresh.  It is a necessary part of a dogs diet it helps keep the fluid balance in the body and transmits nerve impulses.
As a result of this we should ensure that we do not give our dogs a diet that is too salty.
You can suffer from dehydration vomiting and diarrhea if you consume too much salt in your diet.
A dogs daily sodium intake should be limited to about one gram per day.
As the amount of sodium a dog processes will differ depending on their size smaller dogs will be able to process less and older dogs will be able to process more.
Salmon has about 605 mg of omega-3 fatty acids in one can or over half your dogs daily recommended intake.
You should evaluate an entire dogs diet to ensure that they are not consuming excessive amounts of sodium in their diets.
Furthermore clean water should always be available to them.
To help process the extra sodium when the body detects that there is too much sodium it gets thirsty.