LOCOWEED DISEASE OF SHEEP 427 



The postmortem examinations of locoed animals do not in all cases show clearly 

 marked evidence of the progress of the disease. Since in all cases of fatal poisoning 

 the locoed animals die of starvation they are profoundly anemic, as would be expected, 

 and, as a result of this anemia, accumulations of coagulated serum in gelatinous 

 form are found in various parts of the body. These accumulations are particularly 

 prominent about the heart. There is also an accumulation of coagulated serum in 

 the cavity of the spinal column. This is almost always present in cases where the 

 loco poisoning has become a chronic condition. 



This remarkable condition in the spinal canal is described as follows by 

 Marsh in the section of his main work devoted to the antomical changes 

 (p. 97-98) : 



The central nervous system is generally in a hyperemic or congested condition. 

 In a few cases clots were found in the lateral ventricles of the brain. We have never, 

 however, found clots in the fourth ventricle .... The serous exudate in the 

 epidural space is especially abundant, and is more or less organized. Commonly 

 it is particularly abundant about the points of exit of the spinal nerves. This condi- 

 tion is rarely absent in chronic locoes In some cases this coagulated 



8erum is especially abundant in the lumbar region .... 



Later (p. 114) he states that the fluid of the epidural space of the spinal 

 canal is rather unusually abundant, and commonly more or less organized, 

 "so that the spinal canal frequently seems to be filled with a jelly like sub- 

 stance." Peters and Sturdevant, Marsh's colleagues, describe as follows 

 the condition as it was met with in a seventeen months old horse which 

 died under loco treatment (21st Annual Report; Agricultiu-al Experimental 

 Station of Nebraska, 1908). Between the dura mater and the periosteum . 

 of the vertebrae enclosing the neural canal all along the spinal cord there 

 was a cherry red transparent organized exudate in great abundance. In 

 another horse the exudate varied from a buff color in the lumbar region 

 to a very dark red in the cervical region. The color of the exudate was due 

 to numerous tiny blood vessels running through in all directions. The ex- 

 udate "was not adherent to either periosteum or dura but clung to the 

 spinal nerves at their origin, since it ran through and filled the opening 

 between the anterior and posterior nerve roots in each case and was thus 

 held in place by these." 



Marsh also autopsied five lambs which died of acute loco disease lasting 

 only two or three weeks (p. 71). All were in good flesh; "all had clots in the 

 lateral ventricles. All had serous coagulum in the spinal canal, and all 

 had congested walls of the fourth stomach. This would seem to confirm our 

 opinion that these lesions are characteristic of the locoed condition, but 

 that in chronic cases they may be more or less masked." There is some 



