224 YETEEINAEY TOXICOLOGY 



Senecio. 



The Senecio Biorchelli and Senecio latifolius are the causes 

 of the so-called Molteno cattle disease, or straining sickness, 

 which affects both cattle and horses. These plants are 

 members of the numerous genus Senecio, represented in 

 Great Britain by the rag-worts (groundsel), which have not 

 very definitely been proved to be injurious. 



Active Principles. — The senecios have received con- 

 siderable attention from the chemical and therapeutic 

 points of view. Common groundsel (;S'. vulgaris) has been 

 shown to contain in the underground parts two alkaloids, 

 senecionine and senecine (Lutz and Grandval, and Lajoux, 

 1895). S. vulgaris has been used in dyspepsia (Dalch^, 

 1904), and 8. jacoboeus in functional amenorrhoea. The 

 latter plant is also the cause of the New Zealand ' Winton 

 disease,' which is acute cirrhosis of the liver. 



Debierre (1889) examined the Mexican S. canicida, or 

 dog poison, and recognised stages of excitement, rest, and 

 spasm in its action. It causes death from respiratory 

 paralysis. The spasms simulate those of strychnine, but 

 the reflex irritability is lowered. 



H. E. Watt* examined S. latifolius from South Africa at 

 the Imperial Institute. He isolated two alkaloids, seneci- 

 foline and in smaller quantity senecifolidine. The former 

 examined by Cushny was found to exercise the same 

 effects as the whole plant. 



Toxic Doses. — According to experiments by the Cape 

 Agricultural Department, quoted by Walsh, J pound daily 

 of S. Burchelli for four days killed an ox on the fifth 

 day, whilst 8 to 10 pounds of S. latifolius in daily feeds of 

 2 to 6 ounces killed in about six weeks. When the plant 

 is common it is not eaten save in times of scarcity, though 

 it is taken freely by strange stock. 



Symptoms. — A good account of straining sickness is 

 given by W. H. Chase,t who fully investigated the disease. 



* Transactions of the Chemical Society, 1909, p. 466 

 ■j- Record, 1904, p. 425. 



