142 DISEASES OF THE HOESE. 



even though the feeding is high, and the attack is nsually precipi- 

 tated by taking the horse from the stable and subjecting it to exer- 

 cise 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 succumb under the first hundred yards 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 abdominal veins (portal) the accumulated store 

 of nitrogenous matter in an imperfectly oxidized or elaborated condi- 

 tion, and as if the blood, surcharged with these materials, were un- 

 able to maintain the healthy 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 gelding. 



Lignieres has found in hemoglobinuria a streptococcus which pro- 

 duced nephritis, bloody urine, and paraplegia in experimental ani- 

 mals, including horses. 



Symptons. — In the milder forms this affection may appear as a 

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

 den exertion and attended by a dusky-brown color of the membranes 

 of the eye 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 oppression, 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 convulsively, 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 elabo- 

 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 tardy recoveries a partial paralysis of the 

 hind limbs may 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 com- 

 plete inability to stand. 



