10 BULLETIN 915, U. S. DEPARTMENT OF AGRICULTURE. 



The average intake of food, both poisoned and unpoisoned, by 

 hungry white rats used in these tests was one one-hundredth of their 

 body weight. 



Twenty per cent of barium carbonate in the rat bait was found to 

 be an efficient concentration. With this percentage a rat is required 

 to eat only one- third or three-eighths of a meal of average size, or 

 one three-hundred- and-twentieth to one two-hundred- and-sixty-sixth 

 of its own weight, in order to secure the ingestion of a lethal amount. 

 With this concentration, many of the rats die within the first 24 

 hours, the chief factor being the consumption of an amount larger 

 than the minimum efficient lethal dose. 



From the results of both the pharmacological and the feeding 

 tests, it would not seem advisable to always expect 100 per cent 

 mortality from the administration of barium carbonate, in proper 

 amounts, to rats. 



BIBLIOGRAPHY. 



(1) Aloy, J., and Cournet, A. 



Recherches toxicologiques sur le chlorine de baryum. J. pharm. cbimie 

 (1918), 17: 76. 



(2) American Medical Association. 



Kept. Council Pharm. Chem. Council Reports (1911): 53. 



(3) Bary, Alexander. 



Beitrage zur Baryumwirkung. Inaugural Dissertation. Dorpat, 1888. 



(4) Boelter, W. R. 



The rat problem, p. 121. London, 1909. 



(5) Crampe, Hugo. 



Bewahrte Mittel gegen Feldmanse. Deut Landw. Presse (1878), 5: 530; 

 Jahresb. Agr. Chem. (1878) 1: 347. 



(6) Crawford, Albert C. 



Barium, a cause of the loco-weed disease. U. S. Dept. Agr., B. P. I. Bull. 

 129 (1908). 



(7) DlECKERHOFF, W. 



Ueber die Wirkung des Chlorbaryum bei Pferden, Rindern und Schafen. 

 Beri. tierarztl. Wochschrift. (1895): 265. 



(8) KlSSNER, G. 



Ueber Baryum-Vergiftungen u. deren Einfluss auf d. Glykogengehalt der 

 Leber. Diss. Schotten (Hessen), 1896. 



(9) Lantz, D. E. 



The house rat: The most destructive animal in the world. XL S. Dept. 

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(10) Malrel, E. 



Fixation des doses minima mortelles, toxiques et therapeutiques, de chlorine 

 de baryum donne par la voie sous-cutanee a la grenouille, au pigeon et 

 au lapin. Com.pt. rend. soc. biol. (1912), 72: 182. 



(11) 



Influence de la voie d' administration sur les doses minima mortelles et sur 

 ies doses therapeutiques de chlorure de baryum. Compt. rend. soc. biol. 

 (1912), 72: 250. 



(12) 



De rinfhience de la voie d' administration sur la production de la diarrhee 

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