Page 522 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Reproductive system: 2.1 The female reproductive tr act 497

VetBooks.ir been divided into three categories: (e.g. a pendulous uterus [often in multiparous mares]
The multifactorial nature of endometritis has
with fluid being unable to work against gravity) or

maiden mares. The persistent accumulation in the
1 Persistent mating-induced endometritis (PMIE). cervical dilation issues as regularly seen in older
2 Chronic uterine infection (CUI). uterine lumen of inflammatory products and debris
3 Sexually transmitted diseases: Taylorella equigenitalis leads to further inflammation, oedema and damage,
(CEM) [notifiable], Pseudomonas aeruginosa, increasing the likelihood of infections and further
Klebsiella pneumoniae capsule types 1, 2 and 5. endometrial damage and fibrosis.

Category 3 can occur at any age, but the others Clinical presentation
are more common in the older multiparous mare. Multiparous mares, often in their teens and with
poor vulval/perineal conformation and pneumova-
PERSISTENT MATING- gina, are particularly predisposed to this condition.
INDUCED ENDOMETRITIS Mares of any age with cervical pathology, either ste-
nosis or incompetence, can also be affected. In many
Definition/overview mares there are no signs before mating, but subse-
A mild transient endometritis can be considered a quently there is fluid accumulation in the uterine
normal event in mares following breeding, foaling, lumen within 12–36 hours. There is early pregnancy
examination or treatment with foreign substances. It loss with repeated return to oestrus and bacteria
is essential for fertility that the mare resolves this and neutrophils evident on endometrial culture and
inflammation quickly. In normal mares this happens cytology. These mares have difficulty in conceiving
within 12 hours post breeding. In mares affected by unless they are identified and treated.
PMIE the uterus is unable to evacuate the uterine con-
tents post breeding within this normal time frame. Diagnosis
This leads to prolonged uterine inflammation and Post-breeding examination within 12–24 hours will
poor fertility, with a high incidence of early embry- usually show intraluminal uterine fluid accumulation
onic death. The delay is primarily due to impaired on ultrasonography and occasionally, in severe cases,
uterine contractility and lymphatic drainage. This intramural oedema (Figs. 2.107, 2.108). Many prac-
may be compounded by anatomical abnormalities titioners rely on ultrasound imaging of intrauterine

2.107 2.108

Figs. 2.107, 2.108 Transverse transrectal ultrasonograms of a uterine horn containing anechoic (2.107) and
echogenic (2.108), more cellular, luminal fluid. Note the uterine wall oedema. (Photos courtesy Tracey Chenier)