22,1 Schwartz: Extracts of Ascarts vitolorum H3 



Experiment 10.— Rat 2 was injected with 1 cubic centi- 

 meter of the extract. Its reactions were the same as those de- 

 scribed for rat 1, but the symptoms appeared more slowly. 



Three frogs and one turtle were used in this series of exper- 

 iments and extract similar to that used in Series IV was 

 injected in quantities of 1 cubic centimeter to each animal. 

 No definite reactions were provoked, however, the animals ap- 

 pearing quite unaffected by the injections. 



SUMMARY OF EXPERIMENTS 



Physiological salt solution extracts of Ascaris vitolorum were 

 quite toxic to guinea pigs and rats. The injection of these 

 extracts intraperitoneally resulted in the appearance of a train 

 of morbid symptoms characterized by a stage of heightened 

 excitability, during which the animal gave evidence of acute 

 distress, followed by a stage of dullness, stupor, and complete 

 prostration, with fatal termination in several cases (experiments 

 1, 2, and 5). Boiling the extract did not destroy its toxicity 

 (experiment 4), and the administration of the extract by mouth 

 produced painful reactions (experiment 6). Cold-blooded ver- 

 tebrates appeared quite refractory to injection with an extract 

 of Ascaris vitolorum that was toxic to rats (Series V). 



DISCUSSION OF RESULTS 



The results of these experiments indicate that Ascaris vito- 

 lorum contains a powerful, toxic substance, or more than one 

 such substance, capable of provoking marked reactions in guinea 

 pigs and rats. Effects produced in these animals as a result of 

 administering salt-solution extracts of Ascaris vitolorum were 

 similar to the symptoms that were shown by calves heavily in- 

 fested with this parasite. Sick calves suffering from gross 

 infestation with Ascaris appeared dull, listless, with head droop- 

 ing, emaciated, had no appetite, and during the acute stage of 

 the disease which led to fatal results showed marked nervous 

 symptoms, as has already been noted in this paper. 



The pathogenicity of Ascaris vitolorum to calves has been 

 noted by a number of investigators whose descriptions of the 

 symptoms of the disease suggest a chronic intoxication of the 

 host with resultant nervous symptoms as well as digestive 

 disturbances. 



