848 Journal of Agricultural Research voi.xx.No. » 



Experiment 3. — Strength of dosage, 191 units. 



Six rats were fed in this experiment. Three rats were fed on January 

 25. Rat 1 was killed on January 26. Trichinae were found in the in- 

 testine. The parasites appeared normal as to size and structure. Rat 



2 was killed on January 29; trichinae in intestines normal; uterus of fe- 

 males packed with embryos. No. 3 was killed on February 2. Numer- 

 ous trichinae were found in the intestines; apparently normal. 



Three rats were fed on January 26. One rat died on February 6. 

 Numerous larvae were found in the fluid expressed from the diaphragm. 

 Intestines showed numerous trichinae. The second rat was killed on 

 February 12. Numerous unencysted larvae were found in the diaphragm. 

 The third rat died on February 24. Numerous encysted trichinae were 

 found in the diaphragm. 



Experiment 4. — Strength of dosage, 81 units. 



Five rats were fed in this experiment. Rats were fed on January 23. 

 Rat 1 was killed on January 26; numerous live trichinae were found in the 

 intestines. Rat 2 was killed on January 29; intestines negative. Rat 3 

 was killed on February 3 ; numerous live trichinae in intestines. Rats 4 

 and 5 were killed on March 15 ; diaphragms heavily infested with trichinae. 



Experiment 5. — Strength of dosage, 35 units. 



Five rats were fed in this experiment. Rats 1 and 2 were fed on 

 January 23. Rat 1 was killed on January 26; numerous live trichinae 

 in intestines. Rat 2 was killed on January 27; results as in No. 1. Rats 



3 to 5 were fed on January 29. Rat 3 died on February 5 ; numerous 

 live trichinae in intestines. Rat 4 died on February 24; diaphragm 

 heavily infested with trichinae. Rat 5 died March 2 ; results as in No. 4. 



Experiment 6. — Dosage, 19 units. 



Three rats were fed on January 23 with the meat treated in this ex- 

 periment. Rat 1 was killed on January 26; intestines contained many 

 live trichinae. Rat 2 died on February 12; diaphragm not infested. 

 Rat 3 died February 26; diaphragm heavily infested. 



Artificial digestion tests in experiments i to 6. — Some of the 

 meat used in each experiment was digested in an artificial gastric juice 

 January 23. The trichinae thus freed from their capsules were examined 

 microscopically. They showed no visible evidence of injury, being 

 active under heat stimulation and remaining tightly coiled at room 

 temperature and thus behaving like normal trichinae. 



Results of experiments of series I. — These experiments indicate 

 that trichinae are seriously injured by sufficiently high dosages of X-rays. 

 Although the trichinae in all six experiments when freed from their 

 cysts by artificial digestion showed no apparent evidence of having 

 been affected by the X-ray treatment, the parasites in the meat that 

 had been exposed to the heaviest dosage (experiments 1 and 2) failed 

 to complete their development when fed to experimental animals. 

 Instead of growing and developing in a normal manner, after the molt 



