H^MOGLOBINUEIA. 505 



being loaded. Besides which they are chiefly fed on tares which 

 at that time will be ripe and comparatively rich in albuminoid 

 material. Then rain falls and the harvest operations are sus- 

 pended ; the horse stands in the stable for a day or so, and an 

 attack of azoturia may be the result. 



" By far the greater number of these cases occur upon the re- 

 sumption of work after rest, but this is not absolutely necessary, 

 and cases of a mild or chronic form are seen in which no cessation 

 of work has occurred, or in horses which are still at rest, but when 

 this is the case the symptoms are more gradual in their develop- 

 ment and differ somewhat from the acute or severer forms of the 

 affection." 



Local influences may have some connection with this complaint, 

 which is common in certain places, and almost unknown in others. 

 It has been remarked that horses which have been fed on hay or 

 grass grown on land that had been manured with an excess of 

 nitrate of soda, are specially liable to it. Robertson has made 

 the same observation with regard to horses fed on large quantities 

 of ripe tares, peas anii beans. Maize appears much less " heating " 

 in this respect. 



This disease has obtained its name of azoturia from the idea (which has 

 been proved to be erroneous) that the urine of horses suffering from it 

 habitually contains an abnormal amount of nitrogen (French mote). 

 As a rule, the urine of horses affected with it becomes albuminous 

 only in the later stages of this complaint, and then from inflammation 

 of the kidneys. We may look upon this disease as an inflammation of 

 certain muscles of the hind quarters, due to irritation caused by broken- 

 up material in the blood. It has been found that at the beginning of this 

 disease, and even before the manifestation of its symptoms, the number of 

 the red corpuscles of the blood is much above normal (sometimes twice as 

 many), and that it gradually comes down towards the usual standard during 

 the progress, of the malady. " In view of this discovery, it would appear 

 that the disease has its starting-point during the period of unwonted rest 

 and liberal diet, which has the effect of raismg the number of red cells in 

 the blood. As soon as the horse is taken out to exercise, the destruction 

 of the superabundant corpuscles sets in, and the products of this destruction 

 are accountable for the remarkable train of symptoms. The colouring 

 matter of the destroyed red cells becomes partly dissolved in the plasma, 

 is carried to the kidneys, and there excreted with the urine ; while part 

 takes the form of minute granules, which become arrested in the capillaries 

 of certain muscles, cut off the supply of nutriment to these, and thus caus^ . 

 their death and destruction" (McFadytan). 



If blood be taken from an affected animal and allowed to stand in any 

 convenient vessel for about twenty-four hours, so as to permit the clot and 

 serum to separate from each other, the serum, which will be on the top, 

 will, on account of the presence of pigment, be of a dark red, instead of 

 the usual straw colour. 



From post-mortem examinations we find that the affected muscles have 

 suffered from inflammatory degeneration, in that they are pale, swollen, and 

 granular, and have more or less lost their characteristic structure (trans- 

 verse striation). Schindelka having proved that the blood in this disease 

 contains an abnormally large proportion of pigment, argues that this exces^ 



