324 MANUAL OF POISONOUS PLANTS 



Mr. H. Lawrence of Spencer, Iowa, recently sent me a specimen of the 



last species mentioned above, writing that : 



"The cattle staggered and had the scours. One man lost 10 head of young animals." 

 Friedberger and Frohner state that the symptoms of poisoning by this 



rush are as follows : 



At first, excitement and anxiety; the sensorium remaining unaffected; later, un- 

 certainty of movement, reeling and staggering; at least, paralysis of hinder limbs, tumbling 

 down, general paralysis, insensibility to external irritants, unconsciousness and coma. 

 Pulse accelerated, appetite at first normal, but in course of time great disturbance of 

 nutrition; sugar in the urine. Course sometimes very acute, death occurring in a few 

 hours, but sometimes protracted (two to eight days), and at times chronic (one to several 

 weeks). In cattle, after excessive eating continuous diarrhoea becomes a prominent char- 

 acteristic along with the paralytic symptoms; while, if the food be persisted with, cachexia 

 and hydraemiea, combined with weakness bordering on paralysis, make their appearance, 

 Autopsy reveals: hyperaemia, oedema, dropsical effusions on the brain and spinal cord, 

 especially on cerebellum; in cases of longer duration, hydraemia. Sometimes inflammatory 

 changes in the mucous membrane of stomach and bowels. Therapeutics: change of fodder, 

 purgatives and stimulants, especially camphor; blisters along the spine. 



Mr. P. J. O'Gara says of this plant : 



It has been found growing along roadsides and railroad tracks, but its occurrence in 

 serious amounts is apparently confined to low moist meadows which are more or less sandy. 

 As before indicated, it is confined mostly to the Missouri bottom. A thorough examination 

 of several meadows in this region has shown that this plant often constitutes one-sixth or 

 more of the bulk of the hay. There is no doubt that this plant causes a great deal of 

 trouble, but to what extent is not known as many of the haystacks which were carefully 

 examined contained the Rattle-box in considerable amount. Horses eating this hay suf- 

 fered the combined effects of both poisonous plants. 



Prof. Jones and Dr. Rich state : 



The first evidence of the trouble is more or less unthriftiness, the horse appearing 

 thin and the muscles wasted. In from two to five weeks, according to the age of the 

 horse and the manner of feeding, the animal begins to lose control of its muscles, sways 

 and staggers like a drunken man, although its eye looks bright, it eats well, and may even 

 try to caper and play. After muscular symptoms become pronounced many cases refuse 

 to lie down, standing until thrown down by disorderly muscular contractions. If it con- 

 tinues to eat the plant the horse in any case soon loses power to stand and goes down, 

 after which it becomes very nervous and struggles violently to get up, the legs become more 

 or less rigid, and at times all the muscles of the body seem convulsed. Even in this 

 condition one well nursed patient lived two weeks. The horses are generally willing to 

 eat, although unable to rise, but become sore and tired from struggling, finally dying from 

 exhaustion. Life is much prolonged by turning from side to side three or four times in 

 twenty- four hours; thus preventing gravitation congestion of the lungs and kidneys. The 

 pulse becomes slow until toward the end when it is rapid and weak. Temperature is be- 

 low normal until the animal goes down, after which some fever develops in consequence 

 of the nervous excitement and violent struggling. The extremities are usually cold, and 

 in the winter horses suffering from Equisetum poisoning suffer severely from the cold, 

 presumedly because of diminished oxidation and consequent low body temperature. The 

 visible lining membranes of mouth, nose, eye, etc., become pale. 



Conditions Influencing the Effect of the Poison. 



Age of the horses. Young animals develop symptoms much more quickly and succumb 

 to the Equisetum poisoning sooner than older ones. In one case under observation a mare 

 eating Equisetum hay did not show symptoms until after four %veeks, while her colt by her 

 side developed typical symptoms of horsetail poisoning and died in ten days. Nine out of 

 fourteen horses on one farm, all fed alike upon good hay, were bedded with swale hay 

 containing large quantities of this weed. They ate this bedding freely and within three 

 weeks all nine showed symptoms of poisoning, the remaining five bedded with straw kept 

 perfectly well. The youngest, a three-year-old, was down and died a few days later. The 

 oldest, an old brood mare, showed but slight symptoms, while the other seven, of inter- 

 mediate ages, all staggered and reeled, although they recovered. 



F ee d. Grain-fed horses resist the action of the poison much longer than those not 

 grained. Horses seem to develop a depraved appetite for the weed. In the last mentioned 



