15 



can be ascertained, there have been no feeding experiments to determine 

 the difference in toxic character between fungus-infested and fungus-free 

 grains. The dangerous properties are said to be most pronounced in wet 

 seasons." 



Animals Affected: The "Veterinarian," 1842, reports the poisoning 

 of pigs from eating darnel mixed with barley. FataHties among horses 

 and sheep have been recorded by Johnson and Sowerby (1861). Cornevin 

 gives the amounts of darnel necessary to kill certain animals as follows: — 



Horse 0.7 pounds per 100 pounds live weight 



Ruminants 1 .5 to 1 .8 pounds per 100 pounds live weight 



Poultry 1 . 5 to 1 . 8 pounds per 100 pounds live weight 



Dog 1.8 pound per 100 pounds live weight 



Human Poisoning: The chief danger to human beings lies in the 

 difficulty of sifting darnel from wheat and other cereals of much the same 

 sized grain. Ground up with the flour in this way, it has caused many 

 cases of human poisoning, although not fatal. A case is quoted by Johnson 

 and Sowerby in which eighty inmates of Sheffield workhouse (England) 

 were affected with violent vomiting and purging after eating oatmeal 

 containing darnel. 



Symptoms: Darnel poisoning induces giddiness, drowsiness, uncertain 

 gait, and stupefacation (Mueller), and in the older animals, vomiting, 

 convulsions, loss of sensation, and death (Pott). The symptoms in the horse 

 are dilation of the pupils, vertigo, uncertain gait, and trembling. The 

 animal falls, the body is cold and the extremities are stiff, respiration is 

 laboured, the pulse is slow and small, and there are convulsive movements 

 of the head and limbs. There is rapid enfeeblement, and death may occur 

 within thirty hours. 



In pigs, foaming, convulsions, and paralysis have been observed: 

 the stomach and intestines were inflamed and the lungs congested (H. C. 

 Long). 



Remedy and Means of Control: As darnel is an annual grass it 

 should be weeded out before it goes to seed. Badly infested crops should 

 be cut green and used as hay. Land upon which the seeds have already 

 fallen, should not again be used for grain until the rotation has included 

 some hoed crops. 



GRASSES CAUSING MECHANICAL INJURIES. 

 Plate V. 



The long barbed seeds and twisted awns of the porcupine grass (Stipa 

 spartea Trin.) and the needle grass (S. comata Trin. & Aupr.) sometimes 

 cause serious injury and even death to domestic animals. Sheep are the 

 greatest sufferers, as the seeds are easily caught by their wool, and finally 

 penetrate the skin and flesh. 



