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SHIVERIXC;, "LM .MO 111 LITE/' 

 ■" Shivj;riX(j " is so called from the resemblance of the muscular spasms to 

 shiverings. Iiiiniobilitc' is the word which the French apply to those cases 

 of muscular weakness which are manifested by the inability of the horse to 

 turn round quickly, without falling^. The horse can walk or trot forwards, 

 but when turned sharply, he falls to the ground. Sometimes a horse turns 

 with great difficulty, but does not actually fall. He moves his hind limbs 

 in an unsteady and irregular way, and seems to have but little power of 

 co-ordinating the movement of this part of the body. This latter condition"^' 

 is generally termed by horsemen broken or sprained back, and is usually 

 due to chronic disease of the spinal marrow. Shivering, imiiiobilitc, and 

 sprained back all constitute unsoundness. Professor Williams records 

 that four young horses, the progeny of a dam which was affected in the back, 

 died from paralysis of the spine, before they had attained the age of three 

 years. A tifth is now living, and shows signs of aggravated nerve disease. 

 Nerve disease is commonly transmitted to the oftspring in the equine tribe, 

 and we mentioned in treating of roaring, a nervous disease often dependent 

 upon dietetic mismanagement, the important part which hereditary disease 

 plays in the production of this malady. 



MEGRIMS, OR CONGESTION OF THE BRAIN. 

 We turn now to the remaining disorders of the nervous system of the horse, 

 namely, megrims, mad staggers, epilepsy, paralysis of the lips, water and 

 tumours in the brain, and lock-jaw or tetanus. We have, in treating of 

 •diseases of the stomach, spoken fully of stomach staggers, and in treating of 

 poisons, we spoke of grass staggers. Now, we have first to consider the 

 two remaining varieties of staggers, and these are megrims or congestion of 

 the brain, and mad staggers, or inflammation of the brain and its 

 coverings. 



Megrims or '• vertigo," also spoken of as '' staggers," occurring in harness 

 or draught horses is almost always due to mechanical impediment to the flow 

 •of the blood from the brain, occasioned by the pressure of too tightly or 

 badly fitting harness. By some, megrims is believed to be due to 

 inflammatory action, but there do not appear to be any grounds for this 

 supposition. It is said that megrims may be produced by exposure to the 

 rays of the sun, or by driving fast after a heavy meal. These causes certainly 

 may increase the tendency to this affection, but it is very improbable that 

 they alone can cause it. As already pomted out, indigestion is liable to be 

 caused by driving fast after heavy meals, and may induce dizziness or 

 staggers, which it is not easy to distinguish from megrims depending on 

 actual congestion of the brain. 



An attack of megrims is generally sudden in its onset, there being 

 •usually no warning symptoms. The animal slackens speed, or stops 



Our readers will understand that the disease termed sprained back has no relation to true 

 sprain of the muscles of the back, of which we shall treat aloni; with other sprains. 



