Page 517 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

492 CHAPTER 2

VetBooks.ir 2.104 healing is very quick in most cases, but occasion-
ally complications, including eventration of bowel
or bladder and/or peritonitis following contamina-
tion, occur. Surgical repair of lacerations is rarely
indicated.

Aetiology/pathophysiology
Lacerations during parturition tend to occur in the
caudal part of the vagina or cranial vestibule (see
Perineal lacerations, p. 476). Cranial vaginal lacera-
tions are usually associated with intromission of the
stallion’s penis during breeding. Some stallions are
Fig. 2.104 A view down a vaginal speculum of a case more likely to cause these injuries and some clini-
of vaginal varicosity showing the bluish enlarged vessel cians consider them to be related to a discrepancy
in the fold of tissue in the ventral vagina (arrow). between the size of the stallion’s penis and the mare’s
vagina. It is more likely to be related to a particular
dorsally at the level of the hymen (Fig. 2.104). stallion’s copulatory behaviour.
Severe cases may involve the ventral and lateral
walls. Haemorrhage may be seen from the vessels. Clinical presentation
It is important to rule out other sources of bleed- In many cases the laceration in the mare is not
ing from the reproductive or urinary tract, including detected at breeding and, by the time the mare is
the placenta. Rectal palpation, transrectal or trans- examined vaginally again, it has healed. In some
abdominal ultrasonography and endoscopy of the cases, fresh blood is noted on the vulval lips and/
tracts may be considered in certain cases. or the stallion’s penis immediately after breeding.
Breeding lacerations usually occur in the cranial
Management dorsolateral vaginal wall. Some are small (<5 cm) and
In incidental cases or where the haemorrhage is only partial thickness, with limited haemorrhage
intermittent and/or slight, no treatment is neces- and rapid healing. Any contamination of the ejacu-
sary. If the haemorrhage is more severe or persistent, late with blood may affect its fertility. Full-thickness
the vessels may be cauterised using lasers or dia- lacerations at this point are peritoneal and contami-
thermy. Some clinicians have tried local injections nation by semen and penile/vaginal debris, and bac-
of 5% formalin solution under endoscopic guidance terial flora can lead to peritonitis. If the laceration is
with some success. Occasionally, large vessels can be noted early, the mare should be monitored for signs
ligated with absorbable suture material. of peritonitis for at least 3–4 days and treatment
instituted as soon as possible. Severe vaginal lacera-
Prognosis tions or ruptures, particularly if they are ventral, can
The prognosis varies with the severity of the vari- lead to bowel or urinary bladder eventration.
cose veins and whether treatment is necessary, but is
generally fair to good. Diagnosis
Vaginal speculum examination may lead to air being
CRANIAL VAGINAL LACERATIONS aspirated into the abdominal cavity if the tear is
full thickness and peritoneal, and the vagina then
Definition/overview becomes dilated. The tear is often identified in the
Cranial vaginal lacerations can occur during partu- cranial region just dorsal to the cervix. Alternatively,
rition, but more commonly they are related to acci- the vagina can be manually palpated. If peritonitis is
dents occurring at breeding. Many of the lacerations suspected, peritoneal centesis and ultrasonography
occur dorsally and are easily missed. Spontaneous of the abdomen may help confirm this suspicion.