42 STRONG AND TEAGTJE. 



On this date 19 grams of arsenophenylglycin were injected intravenously. The 

 animal was brought to Manila two days later. At this time there were no 

 evident symptoms of surra. On December 27, 20 grams of arsenophenylglycin 

 were again injected intravenously. On January 6, 23 grams of the drug were 

 given intravenously. The blood remained negative, although almost daily exam- 

 inations of it were performed, until February 2, when a few trypanosomata were 

 found present. On February 2, 25 grams of arsenophenylglycin were injected 

 intravenously. A monkey was inoculated on this date with the blood of this 

 mule and it later developed surra. The mule died on February 9, the treat- 

 ment having evidently proved unsuccessful. 



Surra in Bulacan Province. — A small outbreak of surra recently oc- 

 curred in Bulacan Province, near Manila, and a few of the infected 

 animals were treated there. The treated animals were all kept and 

 worked together. Consequently, when a relapse of the infection occurred 

 in one of them the others were exposed. It was practicable to visit 

 the animals for examination and treatment only once a week. Owing to 

 the favorable results that had been reported by Holmes in India from 

 the treatment of trypanosomiasis in horses by a combination of atoxyl 

 and orpiment, we determined to give this method, also, a trial in these 

 animals. Seven mules and 3 horses were treated in a somewhat similar 

 manner, as may be seen from the notes of the experiments which follow. 

 In some instances arsacetin or arsenophenylglycin was substituted for the 

 atoxyl. 



Five mules were given alternate doses of atoxyl and orpiment, the 

 atoxyl being given subcutaneously and the orpiment (arsenic trisulphide) 

 by mouth. In all but one of these, relapses occurred shortly after the 

 treatment was stopped, and we deemed it advisable to substitute arseno- 

 phenylglycin for this method of treatment. The details of these experi- 

 ments are as follows : 



Horse No. 0,2. — Native horse ; contracted surra naturally. Length of time 

 infected unknown. Numerous trypanosomata in the blood at the time of entrance. 

 On December 4, 5 grams of arsacetin were given subcutaneously. On December 

 5 no trypanosomata were found. On December 10, 10 grams of arsenic sulphide 

 were administered by mouth. Following this, the horse became unable to rise 

 and died of arsenic poisoning on December 8. The arsenic sulphide used in this 

 case was precipitated and was not thoroughly washed with alcohol or ether and 

 probably contained a percentage of white arsenic. 



Horse No. 23. — American horse infected with 5 cubic centimeters of the blood 

 of horse No. 22 on December 3. On December 7 its blood was positive for 

 trypanosomata. The parasites became numerous on December 9, on which date 

 15 grams of arsenic sulphide were administered in capsule by mouth. On 

 December 10 the parasites were still numerous; December 11, only one trypano- 

 soma was found in a drop of fresh blood. On the same date 5 grams of 

 arsacetin were injected subcutaneously. On December 13 another dose of 10 

 grams of arsenic sulphide was given. December 16, 5 grams of atoxyl; December 

 23, 10 grams of arsenic sulphide; December 27, 5 grams of atoxyl; January 2, 

 20 grams of arsenic sulphide; January 5, 5 grams of atoxyl; January 9, 20 

 grams of arsenic sulphide; January 13, 5 grams of atoxyl; January 17, 25 

 grams of arsenic sulphide. 



