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results obtained are not entirely conclusive. The poisonous properties 

 of rattlebox {Crotalaria sagittaUs) were demonstrated by the South 

 Dakota Station, and those of some lupines by the Montana Station. 

 According to recent experiments at the Vermont Station the common 

 horsetail {Equisetwn arvense) may cause poisoning when present in hay. 

 It was found that when horses were fed cured horsetail equal in amount 

 to not more than one-fourth of their coarse fodder ration, symptoms 

 of poisoning were noticed, and if the feeding was continued the horses 

 died. The symptoms of poisoning were less noticeable with young 

 than with old horses, and also when a liberal grain ration was supplied. 

 It was also observed that the green plant was less harmful than the 

 dry, possibly owing to the fact that green fodder is somewhat laxative. 



Feeds which are ordinarilj" wholesome ma}^ under certain conditions 

 be harmful. Thus, there is a widespread and apparently justifiable 

 prejudice against moldy or decomposing feeding stuflFs. Experiments 

 carried on at the Kansas and Indiana stations showed that the contin- 

 ued feeding of moldy corn induced intestinal and nervous disorders 

 of a serious nature. It is a matter of common observation that feed 

 which has been wet will ferment or sour readily and cause intestinal 

 disorders. This has to be guarded against especially in warm climates. 



Plants which are ordinarily wholesome may become harmful if 

 infested with ergot. The effect of ergot on horses has been studied by 

 the Iowa, Kansas, and Montana stations and others. It is generally 

 conceded that the presence of ergot is a cause of rheumatism. Some 

 feeds which are regarded as wholesome when properly fed may some- 

 times prove injurious if fed for a long time or in improper quantities. 

 Thus, millet hay, in many sections of the Western United States, is 

 believed to cause the so called millet disease of horses. This question 

 was studied by the North Dakota Station. It was found that long- 

 continued feeding of millet hay caused lameness and other symptoms 

 of poisoning, but the specific cause to which the dangerous properties 

 of millet are due was not learned, though later work at the station 

 indicates that it is a glucosid. 



An explanation of the poisoning of stock by young sorghum and 

 some other forage plants is offered b}^ the discovery of a peculiar 

 glucosid in a number of varieties of sorghum {Sorghum vulgare), which, 

 under the influence of a special ferment present in the plant, liberates 

 prussic acid. It is thought probable that this acid, which is a ver}'^ 

 active poison, may be likewise liberated in the digestive tract of ani- 

 mals feeding on the young plants. 



For a number of years the Nebraska Experiment Station has studied 

 sorghum poisoning, and has recently demonstrated the presence of 

 prussic acid in the green leaves of young and old sorghum plants and 

 Kafir corn. The poison, it is stated, is alwa3\s present in at least 

 minute traces, but ])ecomes dangerous only when the plant is arrested 

 by dry weather at certain stages of its growth. Sunlight, such as pre- 



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