208 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



tation. These bodies are felt to be much harder than those formed 

 by casein, and the milk usually contains gritty particles. Extraction 

 may be attempted by simple milking in the case of the finely divided 

 gritty matter, or with the spring dilator in the case of the larger 

 masses. Should this fail the teat may be laid open with the knife 

 and sewed up again or closed with collodion, but such an operation 

 is best deferred until the cow is dry. 



TEAT BLOCKED BY A WARTY OR OTHER GROWTH INSIDE. 



In this case the obstruction may be near the orifice of the teat 

 or higher up, and the solid mass is not movable up and down with 

 the same freedom as are concretions and calculi. The movement is 

 limited by the elasticity of the inner membrane of the teat from 

 which it grows, and is somewhat freer in certain cases because the 

 growth has become loose and hangs by a narrow neck. In the case 

 of the looser growths they may be snared by a fine spring wire passed 

 as a loop through a fine tube (like a teat tube open at each end) , and 

 introduced into the teat. When this can not be done, the only re- 

 sort is to cut in and excise it while the cow is dry. 



THICKENING OF THE MUCOUS MEMBRANE AND CLOSURE OF THE 



MILK DUCT. 



As a result of inflammation extending from without inward, a 

 gradual narrowing of the milk duct may occur from thickening and 

 narrowing of its lining membrane. This may be limited to a small 

 area near the lower end, or it may extend through the whole length 

 of the teat. The stream of milk becomes finer and finer until it 

 finally ceases altogether, and a firm cord is felt running through the 

 teat. If the constriction is only at the outlet, the teat may be seized 

 and distended by pressing the milk down into it from above, and an 

 incision may be made with a sharp penknife in two directions at 

 right angles to each other and directly in the original opening. The 

 knife should be first cleansed in boiling water. The opening may be 

 kept from closing by a dumb-bell shaped bougie of gutta-percha or 

 by the spring dilator. If the obstruction is more extended it may be 

 perforated by Luthi's perforating sound. This is a steel wire with a 

 ring at one end, and at the other is screwed on to the wire a conical 

 cap with sharp cutting edges at the base, which scrapes away the 

 thickened masses of cells as it is drawn back. This may be passed 

 again and again to sufficiently enlarge the passage, and then the 

 passage may be kept open by wearing a long dumb-bell bougie, a 

 thick piece of carbolized catgut, or a spring dilator. If the passage 

 can not be sufficiently opened with the sound it may be incised by the 

 hidden bistoury. This is a knife lying alongside a flattened protector 

 with smooth rounded edges, but which can be projected to any re- 

 quired distance by a lever on the handle. The incisions are made in 

 four directions and as deep as may be necessary, and the walls can 

 then be held apart by the spring dilator until they heal. In case the 

 constriction and thickening of the canal extend the whole length of 

 the teat, it is practically beyond remedy, as the gland is usually in- 

 volved so as to render it useless. 



