Mare

Question 1

List the arrangement of the peitoneum pouches from dorsal to ventral and what structures they lie between

Answer 1

Rectogenital pouch (ventral to rectum and extends dorsally around rectum right/left pararectal fossa)

Vesicogenital pouch (ventral to uterus under broad lig or genital fold in male)

Pubovesical pouch (ventral to bladder)

Question 2

Answer 2

1 Rectum
2, vagina
3, bladder
4, parietal peritoneum
5, broad ligament
6, lateral lig. of bladder
7, median lig. of bladder
8) rectogenital pouch
8’) pararectal fossa
9) vesicogenital pouch
10) pubovesical pouch
11) ureter

Question 3

Clin sig of rectogenital pouch in mares

Answer 3

It extends beyond the cervix

If vaginal perforation or rectogenital fistula occurs then contamination can enter into peritoneum and feces/infection spread t/o abdomen

Question 4

What is rectovaginal fistula

Answer 4

Occurs when animal has atresia ani (no anus) so fecal matter builds up and fistula forms from rectum to vagina so fecal matter has an outlet through the vagina

Problematic if occurs close to cervix and enters rectogenital pouch

Question 5

Compare/Contrast perlvic and urogenital diaphragms

Answer 5

Pelvic: Primarily muscles and anchors rectum
Urogenital: primarily fascia and anchors reproductive tract

Question 6

What is the perineal body and clin sig

Answer 6

fibromuscular mass
between the rectum and anus dorsally and the urogenital tract ventrally.

May be torn in foaling (perineal laceration) so preventative episiotomy may be performed

Question 7

Where are ovaries located and how does it change with pregnancy

Answer 7

In sublumbar region
Caudal to kidney (far cranially) at mid-distance between tuber coxae and last rib

Move ventrally with pregnancy

Question 8

Describe post natal ovary development

Answer 8

At 6 months the poles grow and pull peritoneum

As an adult, ovulation fossa indentation is formed

Question 9

Name term for green star

Answer 9

Ovulation fossa

Question 10

Describe ovary appearance

Answer 10

Large size (largest of domesticated species, about size of dog kidney)

Large follicles (30-40 mm)
Kidney (bean) shape
Peripheral vascular zone
Hilus at the convex border

Question 11

T/F the follicles and CL can be palpated per rectum in mares

Answer 11

False: only follicles can be palpated
The CL’s do not project from the surface

Question 12

Name the structure

Answer 12

Corpus Luteum

Question 13

How is the ovarian bursa/oviduct unique in horses and clin sig

Answer 13

Infundibulum fimbriae attach to the ovary at the ovulation fossa

Oviduct does not enlarge in size as it reaches the uterine horn and has a sphincter at UTJ
clin sig: prevents ascending infection/salpingitis

Question 14

Answer 14

1, Ovary
2, infundibulum
3, ampulla
4, isthmus
5, uterine horn
6, mesovarium
7, mesosalpinx
8, mesometrium
9, entrance to ovarian bursa.

Question 15

Answer 15

1. Mesovarium
2. Mesosalpinx
3. Abdominal opening of uterine tube
4. Infundibulum
5. ovary
6. ovarian bursa
7. proper ovarian lig. (edge of mesovarium)
8. uterine horn

Question 16

Name these structures and any clin sig

Answer 16

(1) Infundibulum with fimbriae
(2) & abdominal opening
(3) Ampulla
(4) Isthmus (sperm storage)
(5) Uterine papilla and Uterine opening of the
uterine tube (Abrupt change in size at UTJ)

Question 17

Answer 17

1 ovary
2 ovulation fossa
3 mesovarium
4 ampulla
4’ isthmus
5 Infundibulum with abdominal ostium
6 Mesosalpinx (makes lateral wall of the ovarian bursa)
7 Epoeophoron
8. Proper Ovarian Lig
9 Uterine horn
10 Mesometrium
11 Ovarian bursa

Question 18

What type of uterus do mares have

Answer 18

Bicornuate-cruciform (“T-shaped”)

Question 19

Where does the fetus develop in the uterus

Answer 19

In body and one horn of uterus

Question 20

Where does a gravid uterus lie in a mare

Answer 20

on ventral abdomen wall LEFT of midline (left ascending colon is not fixed and can move to accomodate)

Question 21

Name the arteries of the uterus

Answer 21

1. uterine br. of the ovarian
2. The uterine artery from the ext. iliac
3. Uterine br. of the vaginal

Question 22

Where is the broad lig attached in mares and clin sig

Answer 22

Dorsal side of uterus

clin sig: uterus feels smooth on rectal palpation and uterine torsion is less common due to broad lig firm attachment to abd wall

(vs cows - ventral broad lig attachment so uterus feels rough and can retract uterus during palpation which cannot happen in mares)

Question 23

Describe mare cervix and clin sig

Answer 23

Thick walled and firm and closed by soft, LONGITUDINAL mucosal folds - no transverse like in cows

clin sig: mare cervix is easily dilated so AI is relatively easy compared to other species

Question 24

What is the annular fornix

Answer 24

Area around cervix projection into the vagina

Question 25

Describe the vagina of the mare

Answer 25

Longitudinal folds Vaginal fornix and vestibulo-vaginal ring structures Has retroperitoneal and peritoneal protions

Question 26

What is the vestibulo vaginal ring and clin sig

Answer 26

Transverse fold (hymen) prevents pneumonvagina

Question 27

Answer 27

1) cervix 2) vaginal fornix 3) vagina 4) cervical os 5) uterine body 6) ovary

Question 28

Answer 28

1) uterine body 2) fornix vagina 3) vulva 4) vestibule 5) transurethral fold (hymen) 6) vagina 7) bladder 8) fornix vagina 9) cervical longitudinal folds 10) ovary

Question 29

What is the external urethral orifice and where is it located and clin sig and species differences

Answer 29

External Urethral Orifice: CAUDAL to the transverse urethral fold (remnant of the hymen), at the junction bet. Vagina and vestibule. clin sig: This fold may sag cranially in older mares --> urine into vagina --> vaginitis & metritis Urethral fold not like “urethral tubercle in K9

Question 30

name glands present in the vestibule

Answer 30

Minor vestibular glands Vestibular bulbs

Question 31

what is the vestibular bulb analogous to in the male?

Answer 31

corpus spongiosum penis note: swells during mating but no tie in horses

Question 32

describe proper vulvar conformation and why it is important

Answer 32

Vulvar lips full, firm & meet evenly at midline Vertical orientation of vulva and anus in relation to one another (perpendicular to the ground) important because if anus is pulled cranially. feces & urine can enter the vestibule causing contamination and wind-sucking

Question 33

how is vulvar shelf/windsucking treated

Answer 33

caslick' procedure where vulvar cleft is sewn shut, except for an opening for urination. note: Mare should not be bred by a stallion and mare will need an episotomy before foaling

Question 34

what is winking

Answer 34

estrus behavior or following urination when Mares voluntarily contract the vulvar muscles and ischiocavernosus mm. & expose the glans clitoris “winking”

Question 35

clin sig of clitoral fossa

Answer 35

can harbor Taylorella equigenitalis aka contagious equine metritis (CEM)

Question 36

Answer 36

1. Clitoral fossa: 2. Clitoris 3. vestibule

Question 37

how is vulva related to ischial arch and clin sig

Answer 37

The ventral commissure is situated ~ 5 cm. below the ischial arch. In older mares, decrease muscle tone in the abdominal wall. Hence, rectum & anus drawn cranially; change angle of declination of vulva. Vulva tends to sink in at the top as if it were falling into the pelvic cavity; predisposing it to fecal contamination.