IXJCJilES TO THE TKATS. 699 



higher, and the whole or a portion of the sinus be obliterated, then this 

 prominence will not be produced, and the obstacle will bo discovered 

 towards the base of the teat. 



Occlusion brought about by inflammation, hypertrophy of the mucous 

 membrane lining the sinus, or the development of any growth — as a 

 wart — does not occur suddenly ; and in milking it will be observed that 

 the stream of fluid gradually becomes smaller, until at last it can only 

 be drawn drop by drop, or its flow has completely ceased. 



Treatment. 

 When the occlusion is only due to the skin — which is not uncommon 

 in primipane — a small crucial incision made through it by the bistoury 

 or lancet is generally all that is necessary. The sinus of the teat is 

 distended with milk by pressure from the base, and the prominence at 

 the end is then incised. To prevent the wound closing, a small bougie 

 is introduced into the sinus for four or five days until the wound has 

 cicatrised ; it should only be taken out at milking-time. Fiirstenberg 

 states that he has seen the opening thus made remain permeable during 

 the whole period of lactation, but close again when this period expired ; 

 and a second operatiou had to be performed at the next calving. 



4^^ 



B. 

 Fig. 223. 



LCTHI's rERKOB.VTING SoCNn. 



A. Il.alf the Natural Size. R. Natural Size and Section of the Cone. 



When the obstacle is in the sinus of the teat, at the narrow part of 

 the canal, and immediately above the sphincter, a fine trocar or stocking- 

 needle, previously cleaned in boiling water and dipped in carbolic acid 

 solution, must be passed into it and through the obstruction, when the 

 milk will flow. To prevent closure, the cannula of the trocar or a teat- 

 syphon may be inserted for some days, the opening being closed by a 

 cork except at milking-time. Or a solid gutta-peixha sound may be 

 employed until an artificial mucous membrane is formed, removing it 

 when milking. 



When the canal is only partially obstructed and the milk yet flows, 

 the introduction of a small feather — pigeon's — or a piece of thick catgut, 

 will, with a little patience, gradually effect dilatation. But should it 

 not suffice, and particularly if a wart is the cause of obstruction, an 

 incision will be necessary. Various instruments have been proposed for 

 this operation, but Liithi's sound (Fig. 223) is perhaps the best. This 

 is an iron wire about eight millimetres long and two in diameter, having 

 a ring at one end, and at the other a steel cone screwed on to it. This 

 cone has a very sharp point, and both sides have cutting edges at the 

 base or widest part. It is passed into the opening of the teat, pushed 

 through the obstacle, and then gently turned round from side to side 

 until no resistance is felt. Then it is withdrawn, and a bougie or teat- 



