220 BUREAU OF ANIMAL INDUSTRY. 



the breathing becomes painful from the spasm of the muscles used in 

 respiration; the jaws are com.pletely set, eyeballs retracted, lips drawn 

 tightl}^ over the teeth, nostrils dilated, and the animal presents a pic- 

 ture of the most extreme agony until death relieves him. The pulse, 

 which at first was not much affected, will become quick and hard, or 

 small and thready when the spasm affedts the muscles of the heart. 

 In the subacute cases the jaws may never become entirely locked; the 

 nervous excitabilit}' and rigidity of the muscles are not so great. There 

 is, however, always some stiffness of the nock or spine manifest in 

 turning; the haw is turned over the eyeball when the nose is elevated. 

 It is not uncommon for owners to continue such animals at their work 

 for several days after the first symptoms have been observed. All the 

 s3Miiptoms may gradually increase in severity for a period of ten days, 

 and then gradually diminish under judicious treatment, or they may 

 reach the stage wherein all the characteristics of acute tetanus become 

 developed. In some cases, how^ever, we find the muscular cramps 

 almost solely confined to the head or face, perhaps involving those of 

 the neck. In such cases we have complete trismus (lockjaw), and all 

 the head symptoms are aeutel}'^ developed. On the contrary, we may 

 find the head almost exempt in some cases, and have the body and 

 limbs perfectly rigid and incapable of movement without falling. 



Tetanus may possibly be confounded with spinal meningitis, but the 

 character of the spasm-locked jaw, retraction of the eyeballs, the difli- 

 culty in swallowing due to spasms of the muscles of the pharynx, and, 

 above all, the absence of paralj^sis, should serve to make the distinc- 

 tion. 



Prevention. — Where a valuable horse has sustained a ^'>ound that it 

 is feared may be followed by tetanus, it is well to administer a dose of 

 tetanus antitoxin. This is injected beneath the skin with a hj^poder- 

 mic syringe. A very high degree of protection may in this way be 

 afforded. 



Treatment. — The animal should be placed in a box stall without 

 bedding, as far away as possible from other horses. If in a country 

 district, the animal should be put into an outbuilding or shed, where 

 the noise of other animals will not reach him; if the place is moder- 

 ately dark it is all the better; in fly time he should be covered with a 

 light sheet. The attendant must be very careful and cjuiet about him, 

 to prevent all unnecessary excitement and increase of spasm. Teta- 

 nus antitoxin appears to be useful as a remedy in some cases, if given 

 in very large c^uantities early in the disease; otherwise it is useless. 

 Subcutaneous injections of carbolic acid in gl3"cerin and water (car- 

 bolic acid, 30 grains, glycerin and water each 1 ounce) appear to be 

 useful in some cases. Injections should be given twice dail3\ 



A cathartic, composed of Barbados aloes, 6 to 8 drams, with which 

 may be mixed 2 drams of the solid extract of belladonna, should be 



