Salmon and trout are healthy, if expensive, meals for humans. However, they can kill dogs. It is called salmon poisoning, but can happen with any fish that spends its’ time swimming against the river current. You may think that would not be an issue here, but it is. Texas Parks and Wildlife stocks certain ponds and lakes with trout each winter for fisherman to catch. Most grocery stores carry salmon and trout.
While you may never intentionally feed your dog raw fish, he may get into the garbage and help himself if you are not careful. There has been a report of a fisherman feeding the guts of his trout catch to his dog, and the dog getting sick. What exactly is it in these fish that makes the dogs so sick?
Salmon and trout have a parasite, called Nanophyetus salmincola. The parasite has another parasite, called Neorickettsia helminthoeca. It is this second parasite that is the killer. N. helminthoeca is a rickettsial organism, much like some of the water parasites that have infected our water here in recent years. Dogs are, for some reason, the only species that suffer from salmon poisoning.
Within six days of eating salmon or trout, the dog will start vomiting, show a lack of appetite, fever, diarrhea, weakness, swollen lymph nodes, and dehydration. If your dog starts showing these symptoms it is important to take the dog to a veterinarian promptly. Ninety percent of untreated dogs die.
Fortunately, if the dog is treated promptly, he usually recovers. If you know the dog has been in the trash and gotten raw fish, call your vet then. If the dog is showing symptoms and you know he has had raw fish, or might have gotten some, tell your veterinarian. Otherwise, they will waste precious time on diagnostic tests. These tests are both expensive and will not address the problem.
Once the dog is diagnosed with salmon poisoning, he is given antibiotics and a wormer. The antibiotics kill the N. helminthoeca that is the cause of the symptoms and the wormer gets rid of the N. salmincola that harbors him. If the dog is very dehydrated from vomiting and diarrhea, supportive care such as an IV may also be given.
The best thing you can do for your dog is to make sure he has no access to raw fish. Freeze scraps and put them in the trash the day of collection. Refuse to give your dog any part of the raw fish. Make sure he does not have access to the neighbor’s trash, where he might find such scraps.