ACUTE INTOXICATION DOGS. 61 



EXPERIMENTS ON PUPPIBS. 



SERIES C. 



In these experiments the resistance of young growing puppies to caffein was studied. 

 Caffein was given by mouth to all the subjects except one, to which it was administered 

 subcutaneously. The protocols, only a few of which are given, and the tabulated 

 data of the experiments (p. 62) show that the age of the animal has a decided 

 influence on the toxicity of caffein. 



Dog 11. Weight, 1,260 grams. 



August 2: At 10 a. m. given 12.5 cc of 2 per cent of caffein through stomach tube; 

 2 p. m., had convulsions, diarrhea, salivation, and stiffness of limbs. 



August 3: Found dead 9 a. m. Autopsy: Thoracic viscera apparently normal; 

 stomach immensely distended and filled with a white, cheesy mass and some fluid; 

 round worms plentiful in stomach and small intestine; mucosa of entire intestine 

 congested; contents of lower intestine congested; liver pale; spleen flabby; kidney 

 congested. 

 Dog 10. Weight, 1,650 grams. 



July 26: 9.30 a. m., 29 cc of 2 per cent caffein added to 60 cc of milk offered, but 

 refused, and was therefore fed by mouth through stomach tube; 10.25 a. m., no 

 symptoms; 11.30 a. m., restlessness, extremities stiff, post, extremities spread apart, 

 dog shows well-marked symptoms of caffein poisoning; 12.10 p. m., symptoms more 

 severe, extremities extended and spread out, is lying flat on belly so that nose touches 

 floor of the cage; 12.40 p. m., found dead; was alive at 12.10 p. m. Autopsy: Lungs 

 showed hemorrhagic foci in all lobes; heart apparently normal; liver fatty; stomach 

 and intestines filled with round worms; spleen and kidney apparently normal. 

 Dog 9. Weight, 3,000 grams. 



July 25: 350 mg caffein per kilo; 5 p. m., lying down most of the time, occasionally 

 walks about in stall; restlessness present, but not marked; 5.30 p. m., vomit whicn 

 looked frothy and mucilaginous noticed on the floor of the stall; no meat particles 

 noticed in vomit, though searched for; whines occasionally. 



July 26: 9 a. m., looks well; no signs of the effect of caffein given the day .previous. 

 Dog 8. Yellow female. Weight, 3,100 grams. 



July 22: 10.50 a. m., received 1.1 grams of caffein in 10 grams of meat (354 mg caffein 

 per kilo); 3 p. m., vomited mucus; gait clumsy; refused to eat; continually drinking 

 water; very restless; 4 p. m., convulsions set in at 3.55 p. m.; tonic rigidity of the 

 posterior extremities; profuse salivation; convulsions were both tonic and clonic in 

 character, and resembled those seen in rabbits in caffein intoxication; a striking 

 feature was the duration of the spasm, which began at 3.55 p. m. and kept up for more 

 than two hours. 



July 23: Found dead at 9 a. m. 



The data recorded in the table and in the protocols of the experiments of series C 

 show that four out of the seven animals experimented upon died in less than 24 hours 

 after caffein was fed; three of these received 300 to 354 mg caffein per kilo, and one 

 received 200 mg caffein per kilo. No. 8 vomited four hours after caffein was given. 

 No vomiting was observed in the other three dogs. From 0.300 to 0.350 gram of 

 caffein per kilo may be regarded, therefore, as surely fatal to young growing puppies. 

 That this is in all probability the minimum lethal dose appears from the following 

 experiments: No. 9, which received 350 mg per kilo, vomited one hour after and 

 survived, which indicates that some of it was probably not absorbed. The amount 

 which entered the circulation was therefore less than 350 mg per kilo. Since No. 15, 

 which received 250 mg caffein subcutaneously, likewise survived, the probabilities 

 are that 300 to 350 mg per kilo were the minimum fatal doses for these animals. More- 

 over, No. 12, which received 200 mg caffein per kilo, survived, no vomiting having 

 been observed. The case of No. 11, in which the same amount of caffein in proportion 

 to body weight proved fatal, may be explained perhaps by the findings of the autopsy. 



The results obtained in these experiments justify the conclusion that young growing 

 dogs can stand larger doses of caffein than full-grown and older dogs. 



Attention may also be called here to the difference in the symptoms produced by 

 caffein in very young and in adult dogs. It was often noticed in these experiments 



