Page 529 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

504 CHAPTER 2

VetBooks.ir 2.113 2.114

Fig. 2.113 Multiple endometrial cysts seen in a Fig. 2.114 Very large and multiple endometrial cysts
16-year-old Thoroughbred mare on transrectal seen in an aged mare on transrectal ultrasonography.
ultrasonography. (Photo courtesy Tracey Chenier)

2.115 although in those mares that do continue cycling
(and may short cycle) the owner often reports a very
thick, purulent vaginal discharge when the mare is
in oestrus. The mare may be presented for preg-
nancy diagnosis.

Differential diagnosis
Endometritis; metritis; pregnancy; mummified fetus.

Diagnosis
Rectal palpation reveals an enlarged uterus with a
‘doughy’ feel. The uterus can contain up to 60 litres
of material and mimic a pregnancy. Ultrasonography,
transrectally or transabdominally, will confirm the
presence of a large uterus without a fetus but con-
taining large amounts of floccular fluid (Fig. 2.116).
Fig. 2.115 A 33-day pregnancy adjacent to a
uterine cyst. Hysteroscopy will allow direct visualisation of the
exudate. Haematology and biochemistry results are
usually unremarkable. Bacterial culture of the uter-
North America in association with chronic P. aeru- ine fluid may reveal pathogenic bacteria/fungi, but
ginosa infections. in some cases it is sterile. Cervical adhesions may be
detectable per vagina. After drainage of the uterine
Clinical presentation fluid, endometrial biopsy is vital in order to establish
Many cases have no or irregular oestrous cycle a long-term prognosis for fertility. Many cases have
behaviour, although the occasional affected mare irreparable endometrial damage and some have con-
cycles regularly. There are usually no systemic siderable endometrial atrophy, increasing the risks
disease signs and sometimes no vaginal discharge, associated with biopsy collection.