33 



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 gener- 

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

 Some feeds which are regarded as wholesome when properly fed may 

 sometimes 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 

 sj^mptoms of poisoning. From the experiments and observations the 

 conclusion was drawn that feeding millet alone as a coarse fodder is 

 injurious to horses, since it produces an increased action of the kid- 

 ne3's and causes lameness and swelling of the joints and an infusion 

 of blood into the joints. It may also injure the texture of the bones, 

 rendering them soft and less tenacious. The bad effects due to long- 

 continued feeding of millet were observed whether the crop was cut just 

 when the heads were fully ripe or earlier, although there is a popular 

 belief that the trouble is due to harvesting the crop before the heads 

 are fully ripe. The investigation seemed to show conclusively that 

 feeding millet produced millet disease, 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 by the discovery by Dunstan and 

 Henry* of a cyanogenetic glucosid in a number of varieties of sorghum 

 {Sorghuni vulgare), which under the influence of a special ferment 

 present in the plant liberates prussic acid. It is thought probable that 

 this acid may be likewise liberated in the digestive tract of animals 

 feeding on the young plants. The}' did not find the glucosid in the 

 mature sorghum. For a number of years Peters, Avery, and Slade,*^ 

 at the Nebraska Experiment Station, have studied sorghum poisoning, 

 and have recentl}^ demonstrated the presence of cj^anic acid in the 

 green leaves of young and old sorghum plants and Kafir corn. 



METHOD OF FEEDING. 



The method of feeding is a subject which is often discussed, the 

 questions of especial interest being the comparative merits of cooked 

 and raw feed, dry and soaked grain, ground and unground grain, and 

 cut or chaffed and uncut coarse fodder. The number of experiments 

 which have to do with these topics is not numerous. 



"North Dakota Station Buls. 7, 26, and 35. 

 &Proe. Roy. Soc. [London], 70 (1902), p. 153. 



c Nebraska Station Rpt. 1902, pp. 50, 55; Jour. Comp. Med. and Vet. Arch., 23 

 (1902), p. 704; Jour. Amer. Chem. Soc, 25 (1903), No. 1, p. 55. 



17399— No. 125—03 3 



