Lecture 4 Equine

Question 1

Routine Breeding Soundness Exam

Answer 1

• Perineal conformation and
examination of the vulva
• Mammary gland
• Palpation per rectum
• Transrectal
ultrasonography
• Vaginal examination
• Endometrial cytology and
culture
• Endometrial biopsy

Question 2

Advanced Breeding Soundness Exam

Answer 2

• Endocrinology
• Hysteroscopy
• Cytogenetics
• Laparoscopy

Question 3

Anestrus - acquired or congenital

Answer 3

 History
– Mare has shown regular cycle or has foaled before
– Mare never showed any reproductive activity

Question 4

Age of first breeding

Answer 4

Older than 2 years of age

Question 5

When is fertility going to decline?

Answer 5

into the teens (15 years maybe); earlier for thoroughbreds due to conformation problems

Question 6

Anoestrus – Persistent CL

Answer 6

• Normal ovarian size, CL
present (ultrasound or
progesterone)
• Uterus: tone (no pregnancy)

Question 7

Length of diestrus

Answer 7

• Diestrus can last 60 to 90 days

Question 8

Treatment of persistent CL

Answer 8

 PGF2α (Dinoprost
thrometamine)
 Analogue (cloprostenol, less
side effects)
 Spontaneous recovery
possible

Question 9

Anestrus – Persistent endometrial cups

Answer 9

• Embryonic Death (>35 days)
• Endometrial cups already formed
• Normal genital tract on palpation

Question 10

Testing for persistent endometrial cups

Answer 10

• eCG (commercial kits)
• Biopsy or hysteroscopy
• Check for reasons of embryonic
loss: Fibrosis, metritis, iatrogenic

Question 11

What prostaglandin is preferred?

Answer 11

cloprostenol fewer side effects

Question 12

When are the persistent endometrial cups?

Answer 12

45 days of pregnancy

Question 13

Anoestrus – Ovarian tumors

Answer 13

• Not very common
• Ovarian tumors that may cause anestrus
 Granulosa-Theca cell tumor (GTCT)
 Luteoma (rare)
• Need to differentiate from other causes of ovarian
enlargements

Question 14

Anoestrus - Pyometra

Answer 14

 Pyometra is usually not a
cause but a consequence of
acyclicity
 CL not always present
 Cervical or vaginal
adhesions
 Variable cycle history
 Very old mares
 Poor prognosis

Question 15

Anoestrus – other causes

Answer 15

• Cytogenetic abnormalities: Ovarian dysgenesis (63 XO
Turner syndrome)
• Hormonal Treatments: Progesterone, Anabolic
steroids: negative feed back on the hypothalamus
• Nutrition: Weight loss after foaling, poor body condition
• Old mare syndrome
• Ovariectomized mares
• GnRH implants (ovuplant®) (no longer approved in the
USA)
• Immunization against GnRH (Not approved in the USA)

Question 16

Abnormal interval between ovulations - causes

Answer 16

 Aging
 Anovulatory hemorrhagic follicles
 Unilaterally functional ovary?
• Abnormal duration of estrus
 Short or Split-heat (common in transitional mares)
 Long estrus (NO OVARIAN FOLLICULAR CYSTS IN THE
MARE!!!)
• Abnormal duration of the luteal

Question 17

Abnormal luteal function

Answer 17

• Failure of ovulation
 Anovulatory hemorrhagic follicle
 Equine metabolic disease
• Short luteal phase
 Early release of PGF2α from the endometrium
(endometritis, intrauterine treatment)
 Abnormal corpus luteum function
• Lengthened luteal phase
 Persistent CL with spontaneous recovery
 Early embryonic death

Question 18

Abnormal length of cycles due to aging will happen at what age

Answer 18

25 years

Question 19

do ovarian cysts exist in the mair?

Answer 19

follicular cysts do not exist