Evaluation of Premature Mammary Gland Development and Vaginal Discharge in a Mare in Late Gestation

67 Evaluation of Premature Mammary CASE PRESENTATION A nine year-old Quarter Horse pregnant mare (277 days in gestation) was presented to Department of Large Animals, the Koret School of Veterinary Medicine, the Hebrew University of Jerusalem, for evaluation of premature udder development and vaginal discharge. According to the owner, the mare was used as a pleasure riding horse, and was generally healthy. She delivered 4 healthy foals in previous years with no observed problems. The current pregnancy was achieved after the mare was artificially inseminated with fresh semen collected from a stallion of proven fertility. During this pregnancy, the owner did not observe any abnormalities; however, on the morning of the presenting day, he noticed udder development as well as vaginal discharge. Upon presentation the mare was bright, alert and responsive. Physical examination revealed a body condition score of 5 on a 9-point assessment system, pink mucous membranes with a capillary refill time of <2 sec, and normal gastro-intestinal sound on auscultation. Heart rate was 44 beats per minutes, respiratory rate was 24 per minute, and body temperature was 37.6°C. The mammary glands were both enlarged, and could be milked easily. Evaluation of the perineal area for conformation revealed that the vulvar lips were angled at about 35 degrees to the vertical, with suboptimal vulvar seal. Scant amount of dry white discharge was detected on the vulvar lips and on the tail hair nearby the perineal area. Transrectal palpation and ultrasonographic examinations of the reproductive tracts revealed a large uterus (appropriate for the gestation day) with a live fetus that moved during the examination. The cervix tone was moderately soft on palpation. Relevant ultrasonographic images that were taken during the transrectal examination are presented in Figure 1. Evaluation of Premature Mammary Gland Development and Vaginal Discharge in a Mare in Late Gestation