WOUNDS AND BRUISES OF THE UDDER. 699 



mammary lymphatic gland of the same side. The lateral efferent lymphatics 

 are divided into two groups, one of which ascends in the perineal region, 

 towards the lymphatic glands round the anus ; the other passes with the 

 blood vessels through the inguinal canal towards the sublumbar region. 



The mammary arteries are derived from the external pudic ; the veins 

 form two series, one accompanying the mammary arteries, the other, 

 more superficial, furnishes the roots of the subcutaneous abdominal vein. 

 Two nerve branches from the lumbar portion of the spinal cord are dis- 

 tributed to the mammary gland. Their mode of termination is unknown. 



The skin covering the udder shows no special peculiarity ; it possesses 

 few or no hairs, but, on the other hand, has in places weil- developed 

 sebaceous glands and large papillary bodies. 



In cattle, the skin of the teats is free of glands, and has no hair. In 

 the teat of the mare, especially near the opening of the milk canal, many 

 glands are found. In sheep and goats, the skin of the teat is covered with 

 a soft hair, and is rich in glands, particularly at its lower end. In swine, 

 the teat is devoid of hair and glands ; but in dogs, single hairs and 

 sebaceous glands exist. 



(1.) WOUNDS AND BRUISES OF THE UDDER AND TEATS. 

 LACTEAL CALCULI. 



Wounds, &c, of the udder and teats are most frequent in cows, 

 and are caused by treads ; animals with large pendulous udders 

 may even tread on their own teats when rising. Similar injuries 

 are also caused by bites (from dogs) or by sharp objects like thorns, 

 when the animal breaks through or leaps over hedges. Sometimes 

 the skin is divided, sometimes only bruised. 



Surface wounds — -that is, such as neither penetrate the gland 

 substance nor the milk ducts — are of no particular importance, and 

 may be treated on general principles. Considerable bleeding 

 sometimes occurs at the base of the teat ; and should the wound 

 open into the gland, there is some danger of the formation of milk 

 fistula?. Though healing then appears to proceed satisfactorily, 

 cicatrisation fails to occur, on account of the milk continuously flowing 

 through the wound, which nearly closes, but leaves a little funnel- 

 shaped opening, termed a milk fistula. This is, however, only to 

 be feared during lactation. Injuries of the teat may produce 

 cicatricial contraction, and consequent difficulty in milking. 



Bruises of the udder cause bleeding, either into the gland ducts, 

 the milk then being mixed with blood, or into the skin and subcutaneous 

 tissue. The blood may be absorbed, as in other soft parts, or infection 

 may occur with formation of an abscess. 



Treatment. In all deep wounds of the udder the first object 

 should be to obtain healing by first intention. Provided the injury 

 be recent, and seem to warrant such an expectation, the edges of 



