122 Diseases of the Genital Organs 



in the uterus, all vessels leading to that organ awaken to a 

 wholly new activity. There are three pairs of arteries con- 

 cerned, the utero-ovarian, the uterine, and the vaginal. In 

 the healthy non-pregnant cow or mare each of these is 

 clearly palpable per rectum, approximately one-eighth inch 

 in diameter and, being but lightly covered, yields a clear, 

 though not strong, pulsation. 



The utero-ovarian artery, analogue of the chief artery of 

 the testicle in the male, arises from the aorta near the ori- 

 gin of the small mesenteric, and, passing downward, back- 

 ward and inward between the peritoneal layers of the broad 

 ligament, divides near the ovary into two branches, one go- 

 ing to the ovary, the other supplying the oviduct and the 

 apex of the uterine horn. Readily palpable in the non-gravid 

 animal, it is soon dragged so far forward that rectal palpa- 

 tion is rendered inconvenient. The two other pairs, which 

 are readily reached, suffice in virtually all cases, and conse- 

 quently the utero-ovarian artery is commonly ignored. Its 

 palpation becomes of great importance in the diagnosis of 

 ovarian tumors. 



The middle or chief uterine artery arises usually from 

 the posterior aorta near its division into the iliacs, or from 

 one of these, and is easily recognized as it leaves the arterial 

 trunk, at almost right angles, in the region of the anterior 

 border of the shaft of the ilium. It curves backward, me- 

 dianward, and finally, in the form of an arc, forward, to dis- 

 appear in the uterine walls at or near to the base of the 

 uterine horn. During this course it lies between the two 

 peritoneal layers of the broad ligament of the uterus, is 

 much longer than the broad ligament and is thrown into nu- 

 merous S-shaped coils. It is readily picked lip per rectum 

 and palpated in the non-pregnant animal and in all stages 

 of pregnancy. With the advent of pregnancy, the artery 

 quickly enlarges and the pulsation becomes strong and 

 bounding. The arterial stream feels as if impeded and there 

 is a sensation of grating not encountered in other healthy 

 arteries. The artery is about one-quarter of an inch in 

 diameter at 120 to 150 days; at eight months it is one-half 



