UNITED STATES DEPARTMENT OF AGRICULTURE 



BULLETIN No. 365 



Joint contribution from the Bureau of Plant Industry, 



Wm. A. Taylor, Chief, and the Bureau of 



Animal Industry, A. D. Melvin, Chief 



jrw^'^w't. 



Washington, D. C. 



PROFESSIONAL PAPER 



September 8, 1916 



LARKSPUR POISONING OF LIVE STOCK. 



By C. DwiGHT Maesh and A. B. Clawson, Physiologists, Poisonous Plant 

 Investigations, Bureau of Plant Industry, and Hadleigh Maksh, Veterinary 

 Inspector, Bureau of Animal Industry. 



CONTENTS. 



Introductory: Page. 

 Historical summary and review of litera- 

 ture 1 



The alkaloids of delphiniums i 



Losses from larkspur poisoning 11 



Common names of larkspurs 13 



Species of delphinium concerned in lark- 

 spur poisoning 



Detection of larkspur species in stomach 



contents 



Experimental work: 



The station at Mount Carbon, Colo 



The station at Greycliff , Mont 



Experimental feedtag of cattle 



Poisoning of horses by larkspur 



Experimental feediag of sheep 



14 



16 



Results and conclusions: 



Animals affected by larkspur poisoning.. 



Symptoms of larkspur poisoning 



The toxic dose of larkspur 



Post-mortem features of larkspur poison- 

 ing 



Toxicity of different parts of the plant. . . 



Age of plants affecting toxicity 



Treatment of cases of larkspur poisoning. 



Methods of prevention 



General summary 



Literature cited in this paper 



Index to species of plants 



Index to experimental feeding of animals. . . 



PART I.— INTRODUCTORY. 

 HISTORICAL SUMMARY AND REVIEW OF LITERATURE. 



There is somewhat extensive literature in regard to the larkspurs. 

 In this summary and review only the more important and significant 

 publications are noted, with especial reference to those that treat of 

 the poisoning of domestic animals. 



The larkspurs have been known from very ancient times as 

 poisonous and medicinal plants. Under the names crrac^ts aypla of 

 Dioscorides and Hippocrates, ayporkpT] crTa<f>ls of Nicander, Astaphis 

 agria or /Staphis of Pliny, and Herba pedicularia of Scribonius 

 Largus, was probably recognized the species Delphiniwn stapMsagria 

 L. Under the narile Consolida regalis were probably included several 

 species. The question of the identity of the species noted by the 

 ancients is discussed in some detail by Huth, 1895, pages 325 and 

 326.1 



*Full titles of articles referred to in the text are given in the list of literature at the 

 end of the paper. 



26876°— Bull. 365—16 1 



