224 



The Philippine Journal of Science 



1913 



In every instance the healthy animals used in the experiments 

 were proved to be free from trypanosomes by rigorous quaran- 

 tine and frequent microscopic examination of their blood. The 

 mule and the horses employed in these experiments were kept 

 for from six to eight months in the screened stable prior to 

 their use for exposure to fly bites or blood inoculation to test 

 the pathogenic nature of the trypanosome involved. The tem- 

 peratures of these animals were registered morning and evening 

 during the period of quarantine, preceding and following each 

 experiment. 



Monkeys, guinea pigs, and rabbits utilized in the experiments 

 were quartered previously in fly-screened cages and declared 

 surra free after ninety days, during which time blood examina- 

 tions were made regularly once or twice weekly prior to the 

 experiments. 



Table I gives the data of these experiments. 



Table I. — Experiments on the mechanical transmission of surra by 



Tabanus striatus. 



Date of 



experiment. 



Trypanosomes in 

 the infected host. 



Flies em- 

 ployed. 



Healthy animal 

 used. 



Result of experiment. 



1912 



Nov. 21 



22 



Dec. 12 



Swarming 



1 

 1 



1 

 2 

 1 

 1 

 1 

 1 

 3 



2 

 2 

 2 



1 

 1 

 2 



6 



Guinea pig 87 



Guinea pig 92 



Guinea pig 111 



Guinea pig 93 



Negative. 



Negative. Subsequently reacted 



to surra by blood inoculation. 

 Negative. 

 Do. 

 Do. 

 Do. 

 Do. 

 Do. 

 Positive on the eighth day. 

 Dead Jan. 22. Blood produced 

 surra in 2 guinea pigs and 1 

 horse. The latter died Mar. 

 1, 1913. 

 Negative. 

 Do. 

 Do. 

 Do. 

 Do. 

 Positive on eighth day. One 

 mule, 2 monkeys, and 2 guinea 

 pigs reacted to inoculation of 

 blood of horse 50. 

 Positive on ninth day. Disease 

 reproduced by blood inocula- 

 tion into 2 monkeys and 2 

 guinea pigs. 



do 



26 



do 



Nov. 21 



22 



30 



Dec. 1 



Numerous 



Swarming 



Numerous 



do 



Monkey P ._ 



Monkey D 



Monkey S 



28 



1913 



Jan. 1 



26 



27 



do." 



Scanty 



Monkey L 



Monkey D 



Horse 66 



Numerous _ 



.. do 



Horse 69 



28 



30 



Feb. 2 



6 to 10. 



Swarming 



Numerous 



Swarming •> 



Scanty to moder- 

 ate, b 



Horse 277 



Horse B-120 



Horse 50 



Horse 342 





Infected guinea pig used. 



•> Infected horse used. 



