UNITED STATES DEPARTMENT OF AGRICULTURE 

 BULLETIN No. 365 



Joint Contribution from the Bureau of Plant Industry, WM. A. TAYLOB, Chief, 

 and the Bureau of Animal Industry, A. D. MELVIN, Chief 



Washington, D. C. 



PROFESSIONAL PAPER 



September 8, 1916 



LARKSPUR POISONING OF LIVE STOCK 



By 



C. DWIGHT MARSH and A. B. CLAWSON, Physiologists, Poisonous Plant 



Investigations, Bureau of Plant Industry, and HADLEIGH MARSH, 



Veterinary Inspector, Bureau of Animal Industry 



CONTENTS 



Introductory: Page 



Historical Summary and Review of 



Literature I 



The Allialoids of Delphiniums ... 8 

 Losses from Larkspur Poisoning . . 11 

 Common Names Of Larkspurs ... 13 

 Species of Delpliinium Concerned in 



Larkspur Poisoning 14 



Detection of Larkspur Species in 



Stomach Contents 



Experimental Work : 



The Station at Mount Carbon, Colo. 

 The Station at Greycliff, Mont. . 

 Experimental Feeding of Cattle . 

 Poisoning of Horses by Larkspur . 

 Experimental Feeding of Sheep . 



Results and Conclusions: Pago 

 Animals Affected by Larkspur Poison- 

 ing 59 



Symptoms of Larkspur Poisoning . 61 



The Toxie Dose of Larkspur ... 66 

 Post-mortem Features of Larkspur 



Poisoning 73 



Toxicity of Different Parts of the 



Plant 74 



Age of Plants Affecting Toxicity . . 75 

 Treatment of Cases of Larkspur 



Poisoning 77 



Methods of Prevention 82 



General Summary 84 



Literature Cited in this Paper .... 87 



Index to Species of Plants 91 



Index to Experimental Feeding of Animals 91 



WASHINGTON 

 GOVERNMENT PRINTING OFFICE 



1916 



