72 PASTORAL AND AGRICULTURAL BOTAN"Y 



studies of Chestnut, Wilcox, the Marshes and Clawson have thrown 

 considerably light upon the subject of lupinosis (Fig. 28). 



Loss of Animals. Sheep have mainly suffered from feeding upon the 

 lupines and the losses have been heavy, but horses, cattle, goats, swine and 

 fallow deer have been poisoned and experiments with small animals show 

 that none were immune to the toxic substances. The losses in Europe 

 have in some years been very great. In 1880 in Pomerania, the loss of 

 sheep was almost 6 per cent. The loss of sheep in America has been heavy. 

 Chestnut and Wilcox (1901) cite that of 2,000 sheep pastured over a 

 region rich in lupine plants, 1,000 sheep were sick and 700 died. In 

 another locality, 1,150 animals died out of a flock of 2500. 



Nature of Poisons. Lupinus luteus the European species, which 

 has been investigated most carefully contains two alkaloids, lupinin (Czi 

 HtoN^Oz) and lupinidin (CgHisN). Investigations in Europe, how- 

 ever, suggest that these alkaloids are not responsible, but that the active 

 substance is ictrogen formed as the result of the growth of microorganisms 

 upon the plant. Investigation of American species has failed to show the 

 presence of ictrogen, but the American lupines contain alkaloids which 

 are toxic or fatal, if a sufficient quantity of the plant is consumed. The 

 lupine alkaloids produce a stimulation and then paralysis of the respira r 

 tory and vasomotor centers, some convulsive centers, the vagus end 

 mechanism and perhaps the vagus center. Large doses given intra- 

 venously paralyze the heart muscles. The fatal doses for rabbits by the 

 stomach are between 30 and 50 grams per kg. of the seeds of Lupinus 

 leucophyllus and L. sericeus and between 70 and 100 grams per kg. for the 

 seed of Lupinus cyaneus. The cause of death is paralysis of the respira- 

 tion. The seeds are the most poisonous, then in order the pods and the 

 leaves. 



Symptoms. Sheep poisoned by lupine froth at the mouth, their 

 breathing is heavy and labored, subsiding into a condition of coma, the 

 animal falling over as in a deep sleep. In acute cases, there is dyspnoea 

 with the tongue and mouth cyanotic and the peripheral blood-vessels 

 congested. Sometimes in these attacks of dyspnoea the animal dies in 

 convulsions. In other cases, the animal dies in coma. The convulsive 

 attacks of dyspnoea, however, may be considered typical of lupine poison- 

 ing. Dropping of the ears is an early symptom and in many cases the 

 poisoned animal is continuallly pushing its head against surrounding 

 objects. When affected on the range, they run about in a frenzied 



