"Get your facts first, and then you can distort them as much as you please." (Mark Twain)
Friday, October 14, 2005
This is primarily a problem in the Pacific Northwest and California. But if you feed a raw meat diet it can be a problem anywhere.
It is caused from the infection by a rickettsial organism, Neorickettsia helminthoeca. SPD has been known since the early 19th century in North America. It had been observed that dogs that ate raw salmon frequently died however the connection between the fluke and the rickettsia was not established at this time.(1) It is unusual in that the rickettsial organism does not directly infect the dog but is instead carried by a parasite, a trematode (flatworm or fluke) called Nanophyteus salmincola through two intermediate hosts first: freshwater snails and salmonid fish (salmon, trout and steelhead).
Nanophyteus salmincola are found to infect freshwater snails particularly Oxytrema plicifer. The infected snail forms part of the salmonid species food web and is ingested. Neither the fluke nor the rickettsial organism act as pathogens in the fish. The dog is exposed only when it ingests the secondary host - an infected fish. After the dog ingests the fish, the encysted fluke larvae burst and embed in the dog’s intestinal tract and the rickettsia are introduced. The cycle continues when ova are excreted in dog feces to infect snails.
It is necessary for your dog to eat raw salmon to get salmon poisoning disease.
A sudden onset of symptoms occur 5-7 days after ingestion of fish. Initial symptoms include lethargy and anorexia. Peaking of temperature between 104-107 in the first two days and then slowly returns to normal. Persistent vomiting by the fourth day. There is bloody diarrhea within a few days of vomiting onset. The diarrhea is often bright yellow color. There are enlarged lymph nodes.
In the acute stages, gastrointestinal symptoms are quite similar to canine parvovirus. Nasal and ocular symptoms can resemble canine distemper. If left untreated, SPD has a mortality rate of up to 90%. Treatment is supportive to maintain hydration as well as antibiotic therapy to kill the disease producing organism. Dogs that survive are immune.
It is preventable by cooking all fish before feeding your dog. If you are outdoors hiking or camping or live near streams and rivers were salmon spawn, keep a close eye on your dog on don't let your pet run free to insure that no fish carcasses are ingested. Please see your vet immediately if you suspect your dog has ingested raw salmon.
Because the disease is so devastating, and so common (apparently) in our little corner of the world, it seems as though there ought to be something positive that dog owners can do. Along those lines, here's some weird - but perhaps wise - advice:
Some dog owners who live near rivers and streams -- and realize it will be hard to keep their pets out of salmon -- purposely allow their dogs to eat some, [Shelton, WA, veterinarian Gary] Olson said.
Then the pet owners watch their dogs and treat them as soon as symptoms appear. The dogs then become immune to the disease.
"That way it's a controlled situation," he said.