DISEASES OF THE OX AND SHEEP. 561 



disease in which the spinal cord is largely implicated. This 

 serious malady we have already described, and all that we need 

 say here in regard to it is that after death from tetanus the 

 spiKial cord and its membranes may be seen to be congested, and 

 that there may be softening of the cord and accumulation of 

 fluid between the membranes. 



Paralysis is a nervous disorder which may be due to many 

 difl'erent causes. An animal is said to be paralysed when it 

 suffers from a loss of voluntary motor power in certain muscles. 

 This want of motor power is generally accompanied by a loss of 

 sensory power also. The connection between the two wants 

 may be due to the contiguity of the sensory and motorial tracts 

 in the case of the spinal cord and most of the nerves. Some- 

 times the whole of one side of the body may be affected, and 

 in these cases the disorder is known under the name of hemi- 

 plegia. It appears to be most commonly the case that both 

 hind limbs are affected in the ox, and when in this state the 

 animal is said to be suffering from paraplegia. The disease may 

 result from pressure on, or from disease of, some part of the 

 nervous system, the brain, the spinal cord, or the nerves. The 

 pressure may be due to a fracture, the paralysis coming on soon 

 after a fall or some other injury. Though the loss of power 

 may in certain cases come on suddenly, it does not usually do 

 so, but may generally first be noticed in a staggering of the gait. 



Paraplegia most frequently attacks animals advanced in age, 

 and especially those that are taken or kept on low and damp 

 pastures in severe weather. Cows which are pregnant may 

 suffer from paraplegia, and recover after parturition. This may 

 be caused by pressure on the posterior aorta, or on the iliac 

 arteries which supply the hind limbs with blood. After death, 

 tumours have in some cases of paralysis been found so situated 

 as to press upon the nerves of the affected part. Again, the 

 disorder may be occasioned by the ingestion of poisons, as in 

 the case of the affection known as lead-palsy. 



Treatment. — The animal should be made to lie comfortably, 

 and be frequently turned, so as to avoid the production of sores. 

 If the disease is very severe, or if we have any reason to sup- 

 pose that there is a serious fracture, such as of the spine, or 

 that the disease is occasioned by tumours, it is best to counsel 

 slaughter. In regard to medicines, it may be said that iodide 



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