DISEASES OF CATTLE 419 



EMPHYSEMA (AIR OR GAS UNDER THE SKIN). 



Emphysema of the skin is not a true disease of the skin, but 

 we shall mention it as a pathological condition. It is characterized 

 by a distention of the skin with air or gas contained in the sub- 

 cutaneous areolar tissue. It may depend upon a septic condition of 

 the blood, as in anthrax or blackleg ; or air may be forced under the 

 skin about the head, neck, and shoulders, as a result of rupture of 

 the windpipe. It occurs in the region of the chest and shoulders 

 from penetrating wounds of the chest and lung, and occasionally 

 follows puncture of the rumen, when the escaping gas is retained 

 under the skin. 



Symptoms. The skin is enormously distended over a greater 

 or less portion of the body ; thus any region of the body may lose its 

 natural contour and appear like a monstrosity. There is a peculiar 

 crackling beneath the skin when the hand is passed over it, and on 

 tapping it with the fingers a resonant drum-like sound is elicited. 



Treatment. Puncture the distended skin with a clean broad- 

 bladed knife and press out the contained air. Further treatment 

 must be directed with a view to the removal of the cause. 



DISEASES OF THE EYE. 



CONJUNCTIVITIS (SIMPLE OPHTHALMIA), 



This is an inflammation of the conjunctival mucous membrane 

 of the eyeball and lids ; in severe cases the deeper coats of the eye be- 

 come involved, seriously complicating the attack. 



Causes. It may result from a bruise of the eyelid; from the 

 introduction of foreign matters into the eye, such as chaff, hayseed, 

 dust, gnats, etc.; from exposure to cold; poisonous or irritating 

 vapors arising from filthiness of stable. Dust, cinders, or sand blown 

 into the eyes during transportation frequently induce conjunctivitis. 



Symptoms. A profuse flow of tears, closure of the eyelids from 

 intolerance of light, retraction of the eyeball and corresponding pro- 

 trusion of the haw, disinclination to move, diminution of milk secre- 

 tion, etc. On parting the lids the lining membrane is found in- 

 jected with an excess of blood, giving to it a red and swollen appear- 

 ance; the sclerotic, or white of the eye, is bloodshot and the cornea 

 may be cloudy. If the disease advances, keratitis results. 



Treatment. Careful examination should be made to discover 

 particles of chaff, etc., which may have lodged in the eye, and upon 

 the discovery of such a cause prompt removal is indicated. This 

 may be accomplished by flushing the eye with warm water by means 

 of a syringe, or, if the foreign substance is adherent to the eyeball or 

 lid, it may be scooped out with the handle of a teaspoon or some 

 other blunt instrument. To relieve the congestion and local irrita- 

 tion, a wash composed of boracic acid in freshly boiled water, 20 

 grains to the ounce, or acetate of zinc, 5 grains to the ounce of pure 

 soft water, may be used, to which may be added 20 drops of lauda- 

 num. A few drops of this should be placed in the eye with a 

 camel's-hair pencil or soft feather three or four times daily. The 

 animal should be placed in a cool, darkened stable, and then a cloth 



