DISEASES OF THE HOESE. 83 



though the feeding be high, and the attack is usually precipitated by 

 taking the horse from the stable and subjecting it to exercise or work. 

 The poisoning is not present when taken from the stable, as the horse 

 is likely to be noticeably lively and spirited, but he will usually suc- 

 cumb under the first hundred j^ards or half mile of exercise. It seems 

 as if the aspiratory power of the chest under the sudden exertion and 

 accelerated breathing speedily drew from the gorged liver and abdom- 

 inal veins (portal) the accumulated store of nitrogenous matter in an 

 imperfectly oxidized or elaborated condition, and as if the blood, 

 surcharged with these materials, was unable to maintain the health}'' 

 functions of the nerve centers and muscles. It has been noticed 

 rather more frequently in mares than horses, attributable, perhaps, 

 to the nervous excitement attendant on heat, and to the fact that the 

 unmutilated mare is naturally more excitable .than the docile geldi ng. 



Lignieres has found in hemoglobinuria a streptococcus which pi'o- 

 duccd nephritis, blood}^ urine, and paraplegia in experimental animals, 

 including horses, 



Sympto7ns. — In the milder forms this affection ma}^ appear as a 

 lameness in one limb, from indefinite cause, succeeding to some sud- 

 den exertion and attended b}^ a dusky-brown color of the membranes 

 of the ej^e and nose and some wincing when the last ribs are struck. 

 The severe forms come on after one or two days of rest on a full 

 ration, when the animal has been taken out and driven one hundred 

 paces or more. The fire and life with which he had left the stable 

 suddenly give place to dullness and oi:>pression, as shown in heaving 

 flanks, dilated nostrils, pinched face, perspiring skin, and trembling 

 body. The muscles of the loins or haunch become swelled and rigid, 

 the subject moves stiffly or unsteadily, crouches behind, the limbs 

 being carried semiflexed, and he soon drops, unable to support him- 

 self. When down, the body and limbs are moved couvulsivel}', but 

 there is no power of coordination of movement in the muscles. The 

 pulse and breathing are accelerated, the eyes red with a tinge of 

 brown, and the urine, if passed, is seen to be highly colored, dark 

 brown, red, or black, but it contains neither blood clots nor globules. 

 The color is mainly due to hemoglobin and other imperfectly ela])0- 

 rated constituents of the blood. 



It may end fatally in a few hours or days, or a recovery may ensue, 

 which is usually more speedy and perfect if it has set in at an early 

 stage. In the late and tardj^ recoveries a partial paralysis of the hind 

 limbs ma}^ last for months. A frequent sequel of these tardy cases is 

 an extensive wasting of the muscles leading up from the front of the 

 stifle (those supplied by the crural nerve), and a complete inability to 

 stand. 



Prevention. — The prevention of this serious affection lies in restrict- 

 ing the diet and giving daily exercise when the animal is not at work. 



