PARASITES AND PARASITIC DISEASES OF DOGS 31 



be somewhat enhanced by the use of preliminary high colonic irriga- 

 tions. The drug is quite safe in the majority of cases, but in many 

 cases the animal will appear depressed and subdued for some time after 

 treatment. Very weak or sick animals must be given diminished doses 

 or given some other and safer treatment if treated at all. In any case, 

 and especially in the case of such sick and weak animals, it is advisable 

 to call in a veterinarian. Other drugs which may be used are those 

 such as oleoresin of male fern, kamala, and freshly ground areca nut. 

 Arecoline hydrobromide may be used for the removal of tapeworms 

 from cats, but the drug is more poisonous for cats than it is for dogs. 

 The dose of the drug is from one twenty -fifth to one-sixteenth grain 

 for adult cats of average weight; the latter dose should not be 

 exceeded. Kamala in a dose of 1 gram in hard gelatin capsules for an 

 average-sized cat is another treatment which is quite effective for the 

 removal of some species of tapeworms from cats. As cats are par- 

 ticularly susceptible to poisoning with tapeworm remedies, it is prefer- 

 able that such remedies be administered by a veterinarian who is best 

 qualified to judge the proper dose of any such drug. 



FLUKE INFESTATION 



There have been a number of species of flukes reported from dogs 

 and cats in various parts of the world. One species, Troglotrema 

 salmincola, is of special importance, since it is responsible for a fatal 

 disease of dogs known as salmon poisoning. 



Cause. — The salmon-poisoning fluke is very small, about one 

 fiftieth to one twenty fifth of an inch (0.5 to 1 millimeter) long, and 

 occurs in the small intestine of dogs. Cats may become infested, but 

 apparently this fluke causes little or no injury to this animal. The 

 distribution of this fluke in the United States is limited to Oregon, 

 Washington, and the northern part of California. 



The life history of the salmon-poisoning fluke, like that of other 

 flukes, is complex. The egg of the fluke passes out in the feces and after 

 a period of incubation in water releases a free-swimming larva or mira- 

 cidium. This larva penetrates into water snails, Goniobasis plicifera 

 var. silicula, and in the course of time gives rise to other larvae known 

 as cercariae. These cercariae escape from the snail host and penetrate 

 into, and become encysted in, the kidneys and flesh of salmonoid 

 fishes. Dogs and other susceptible animals become infested with the 

 parasite by eating such infested fish. 



Symptoms. — The symptoms of salmon poisoning, which develop 

 after the ingestion of infested fish, resemble those of distemper. 

 Recent work by Oregon investigators indicates that the disease is due 

 to a virus, the fluke acting as a carrier of the virus or as an inoculating 

 agent. The disease manifests itself by a sudden rise in temperature 

 about 6 to 8 days after the dog has eaten the infested fish; this rise in 

 temperature is followed by a loss of appetite and marked depression. 

 After the second or third day the temperature drops gradually, and 

 this is followed by a discharge of pus from the eyes and swelling of 

 the eyelids and face. The animal may vomit persistently. On the 

 sixth or seventh day diarrhea sets in, the feces being blood tinged at 

 first and later consisting of almost pure blood. There is a noticeable 

 loss of weight, the temperature drops to subnormal, and usually the 

 animal dies. Recovery is rare, but dogs recovering are immune to 

 subsequent infection. 



