220 NORMAL PARTURITION. 



tender ; and this phenomenon is more particularly remarkable in those 

 animals whose milk is not utilized after the young have been weaned. 

 The mammary glands then become soft, flaccid, and small, and cease 

 to secrete. In such animals as the Mare and Ewe, these glands, ordi- 

 narily small and scarcely perceptible, before parturition become so re- 

 markably developed as to cause alarm in people who do not understand 

 the cause. With the Mare especially, the development of the mammae 

 is sometimes so considerable, that the engorgement extends beneath the 

 abdomen and simulates oedema, or it ascends between the thighs as high 

 as the vulva as a prominent ridge, while the skin in this region is red- 

 dened. At a later period, the teat yields a serous fluid on pressure, or 

 this constitutes a crust around it ; this fluid afterwards becomes some- 

 what lactescent, and finally appears as the "colostrum " or first milk. 



Another premonitory sign is the tumefaction of the vulva, increase of the 

 space between the labia, which become soft and flabby^ while their lining 

 membrane is reddened, and a viscid glairy mucus covers it. This mucus, 

 derived from the vaginal lining membrane, soon becomes so abundant 

 that it is discharged in long filamentous streams, particularly in the Cow, 

 and soils the tail and hooks j it is destined to lubricate the genital pas- 

 sages, and facilitate the extrusion of the foetus. 



With these changes, the abdomen falls, or rather becomes more pen- 

 dent ; the croup looks hollow, as do the flanks, due to the relaxation of 

 the broad ligaments. The spine, particularly in the lumbar region, be- 

 comes more horizontal and rather inclines downward, as if yielding to 

 the weight of the abdomen. The haunches appear to be wider apart, 

 and the gluteal muscles to subside, owing to the falling in or modification 

 of the sacro-ischiatic, as well as the sub-ischiatic, ligaments, from serous 

 infiltration. 



The animal walks sluggishly and unwilingly, and if grazing with 

 others, does not appear to care about following them. Sometimes, as 

 has been mentioned, there is swelling of the limbs, particularly the hind 

 ones. 



If very careful vaginal exploration be made at this time, it will be 

 found that the cervix uteri has become a part of the uterine cavity, and is 

 almost completely effaced, being reduced to merely a thin circular ring ; 

 its tissue is soft, and the os is slightly open in l^iose animals which have 

 previously had young. 



As parturition draws nearer, these phenomena are more marked. The 

 animal also begins to be restless, and continually agitated ; if feeding, it 

 stops for some moments, as if listening to some sound only audible to 

 itself, or as if experiencing some strange internal sensation for the first 

 time, and which may certainly be the preparatory or commencing contrac- 

 tions of the uterus. Not unfrequently the animal lies down and gets up 

 again, as if suffering from colic. Some are quite mute, though anxious 

 and uneasy ; while others, in addition to exhibiting restlessness and dis- 

 tress, utter a half-stifled cry of pain. The Mare whisks its tail, the Cow 

 bellows, the Ewe bleats, the Bitch often whines, and the Cat emits a low 

 cry as if in suffering. If the animal is at liberty, it seeks a remote quiet 

 place in which to bring forth its young ; while some — such as the Bitch, 

 Cat, Sow, and Rabbit — prepare a special nest. 



2. Dilatation of the Os Uteri. — The limit between this stage and the 

 former is not so well marked as our division would indicate. Neverthe- 

 less, it is meant to imply that the stage of dilatation of the os terminates 



