768 DISEASES OF THE WITHERS. 



treatment. The animal, however, ought not to be made to re- 

 sume work imtil it is entirely healed. 



(e) Cyst, or Hygroma. — These terms designate a tumor which 

 usually forms on either the middle or the lateral face of the 

 withers, originating in the dropsical condition of a serous bursa. 

 On whatever part of the withers it may make its appearance, the 

 origiaating cause is the same, and it is the effect of friction, or of 

 the slight but long-continued irritation produced by an ill-fitting 

 harness, inflicted whUe the animal is suffering from parasitic dis- 

 eases. In these cases the connective areolae of the bursa become 

 the seat of an amount of secretion in excess of that which is re- 

 moved by the act of resorption, and the accumulated hyper- 

 secreted fluid gathers into the cavity, to form the serous cyst. 



When located in the median line, the hygroma constitutes a 

 soft tumor, of varying size, from that of a pigeon's egg to that of 

 a child's head — bUobulated, always soft, fluctuating, without heat, 

 and painless ; even transparent, when the skin is pigmentless. It 

 always presents the differential characters of being well defined 

 in its outlines, and without inflammatory peripherical infiltrei- 

 tion. 



When the cyst is on the side of the withers it may present 

 some similar characters, but when it is deep, under the apone- 

 urosis of the trapezium, or even under the rhomboideus, an ex- 

 ploration becomes necessary to establish the differential diagnosis 

 from abscess, as upon the true nature of the tumor depends the 

 immediate indications of treatment. 



Hygroma of the withers may retain their characteristics for a 

 long time, but many change in their nature under the influence 

 of external irritations, bruises, contusions, improper treatment, 

 etc. In that case the cyst is transformed into an abscess, or rather 

 a suppurating cyst. 



In respect to the treatment of cystic withers, the first indica- 

 tion is to remove the cause, and with this not only wUl the accu- 

 mulation of the serosity cease, but the possibility of its trans- 

 formation into the abscess form will be removed. 



When the cyst is small and of recent formation, resolvent 

 treatment is in order, as cantharides ointment, bichloride or 

 biniodide of mercmj pomatums, etc. Actual cauterization, in Hnes 

 or in points, has given satisfactory results in chronic cases. In- 

 jections of tincture of iodine have also been recommended. Our 



