254 Journal of Agricultural Research voi.xvi, No. 9 



In view of the apparent importance of Ascaris as a cause of anemia, 

 the possible relation between the secretions of the parasite * and the 

 anemia of the host has a high degree of practical interest. Certain 

 investigators, notably Schimmelpfennig (9) and Flury (4), attribute 

 hemolytic properties to the body fluids of Ascaris. Flury states, in 

 fact, that the excretions of Ascaris when kept in vitro are hemolytic, 

 and inclines to the view that anemia may be caused by the absorption 

 of toxic substances produced by the worms. Weinberg (12, 13), Whipple 

 (75), Alessandrini (j), and several other investigators, on the other 

 hand, deny the presence of hemolytic substances in Ascaris and state 

 quite emphatically that blood corpuscles of the host in contact with 

 extracts of the worms remain intact. Recently Shiraamura and Fujii 

 (20), in a report of experiments with extracts of Ascaris on various 

 animals, state that alcoholic and ethereal extracts of the parasites are 

 hemolytic, but that watery extracts of the body substance of the worms 

 previously freed from the ether and alcohol soluble portions produce no 

 effect on red blood cells. 



SCOPE AND SUMMARY OF EXPERIMENTAL WORK 



For some time past the writer has been studying the problem of the 

 possible absorption of toxic products by animals harboring ascarids. 

 In this work A. lumhricoides of swine,^ of which an abundant supply is 

 easily obtained, has been utilized. The experiments, the results of 

 which are briefly summarized in this paper, were undertaken with a 

 view of determining (i) whether the body fluids of the parasites are 

 hemolytic, (2) whether the excretions of the worms kept in vitro contain 

 blood-destroying substafices, and (3) the relation which may exist 

 between the anemia of ascariasis and the absorption by the host of 

 toxic substances produced by the parasites. Sufficient data have 

 already been accumulated to warrant certain conclusions, as follows: 



(i) The body fluid of .4. lumhricoides taken from worms shortly 

 after their removal from the host is not hemolytic to the washed eryth- 

 rocytes of swine, cattle, sheep, rabbits, guinea pigs, and rats. 



(2) The fluid from worms which after removal from their host are 

 kept alive in salt solution for a few days acquires hemolytic properties. 

 Fluid from worms kept in vitro for 24 hours is only slightly hemolytic 

 if at all, but fluid from worms kept under similar conditions from six to 

 eight days is decidedly destructive to the red blood corpuscles of swine 

 and sheep. 



(3) The hemolytic property of the fluid is thermostabile and is not 

 destroyed by boiling. 



• Several investigators have shown that the fluid and extracts of human, horse, and swine ascaris have 

 indistinguishable chemical and physiological properties. 



• Ascaris of swine is also referred to as Ascaris suum in order to distinguish it from the form which para- 

 sitizes man. The two forms are morphologically indistinguishable, however, so far as our present knowl- 

 edge goes. 



