Breeding soundness exam of the mare

Question 1

What are 3 reasons for undertaking a breeding soundness exam of a mare?

Answer 1

Insurance exam
Pre-breeding checks
Infertility checks

Breeding soundness ≠ fertility
- consider what you will tell the owner

Question 2

What basic steps are involved in a breeding soundness exam?

Answer 2

History
Generaly physical exam
Special reproductive exam
± special procedures/sampling
Planning ahead

Question 3

What aspects should be assessed in a general history for a breeding soundness exam?

Answer 3

Client's motivations/complaints - what do they want done?
Mare ID 
Age
Breed
Vax/deworming status - individual & herd
Housing status
Training status
Contact with other horses

Question 4

What aspects should be assessed in a reproductive history for a breeding soundness exam?

Answer 4

Reproductive status (pregnant, foal at foot, non-pregnant)
Prior breeding records
Foaling/breeding Hx
Any hx of reproductive problems - abortions, RFM, assisted deliveries, dystocia
Last reproductive event

Question 5

Aspects of a general physical exam (as part of a breeding soundness exam)

Answer 5

Overall condition - BCS
Hair coat condition - hirsutism/PPID
Vitals - TPR, HR, MM, CRT
Eyes (blindness = no photoperiod receptivity TF acycling)
Teeth
MSK exam (lameness = can’t stand being mounted)

Question 6

What areas/organs are examined during a special reproductive exam (SRE) (in order)? How?

Answer 6

External exam (visual/palpation)

• udder
• discharge on tail/vulva > collect sample
• vulva
• perineum
• clioris

Internal exam

• rectal exam (1st) = uterus, ovaries, cervix, broad lig (palpation/US)
• vaginal exam = endometrium (speculum/manual)

Question 7

What aspects of the udder are considered during a SRE?

Answer 7

Symmetry
Activity - lactation/dry
Fibrosis
Signs of acute inflammation
Ticks

Question 8

Aspects of exam of external SRE

Answer 8

Anus/perneal body/vulva in a vertical line
Vulva below ischial arch
Fleshy vulval lips which create a seal
- no air intake when lips parted
Clitoris concealed in clitoral fossa ± swabs of fossa (CEM/Pseudomonas)

Question 9

Aspects of rectal exam of SRE - what organs + what about them is important?

Answer 9

Uterus = body & horns > diameter, tone, wall thickness/oedema, contents (air/fluid/cysts/foetuses)

Ovaries = size, shape, ovulation fossa presence, follicles (presence/size/grade),

Cervix = tone + diameter
Broad ligament - check for haematomas
Pelvic cavity/bony pelvis - check for possible passage of foetus

Correlate all findings to the stage of the oestrous cycle!

Question 10

Why is the rectal exam conducted before the vaginal exam during the internal SRE

Answer 10

Rule out pregancy

Avoid introducing air into vagina/uterus (> poor quality US images)

Question 11

What does the thickness of the uterine wall indicate?

Answer 11

Stage of the oestrous cycle:

• Atonic uterus = anoestrus
• Thin wall (no oedema) = dioestrus
• Thick wall (endometrial oedema) = oestrus

Question 12

Aspects of vaginal exam of SRE

Answer 12

Uterine exam (manual) = collect 2 endometrial swabs in dioestrus (>d5 post-OV - best time to Dx endometritis)

• uterus should be sterile
• high P4 = low defence/WBC

Speculum exam > Dx of persistent hymen, vaginitis, varicose veins, vaginal/cervical adhesions, urovagina

Question 13

How is a vaginal SRE conducted?

Answer 13

Clean + dry perineum before exam (warm water/soap)
Use sterile gloves + sterile lube
Collect 2 endometrial swabs for culture + cytology (in dioestrus)
- double guarded swab > place in transport medium after withdrawal
Finish with IM PGF2a to induce luteolysis (prevent iatrogenic infection)

Question 14

Cytological evaluation of uterine swab - what to look for?

Answer 14

WBCs - neuts/eosinophils
Endometrial cells
Bacteria (presence/#/shape/size)
- location = extracellular or inside neutrophils

Endometritis = > 1:10 nut:endometrial cells
- in dioestrus, should be sterile uterus

Question 15

Culture evaluation of uterine swab - what to look for?

Answer 15

Relate to cytological findings

• FP = + culture but no bacteria on cytology
• FN = – culture but bacteria present on cyt.

Question 16

What are indications for uterine biopsy?

Answer 16

High value mares
Mares dx w chronic endometritis
Infertility of unknown origin
Mares requiring expensive tx

Question 17

Practical aspects of uterine biopsy

Answer 17

Introduce punch manually into uterus > move hand in rectum to push tissue into punch jaw > fix in Bouin’s medium

Avoid sampling near cervix - aim for base of uterine horn (location of embryo implantation)

Question 18

Evaluation of uterine biopsy

Answer 18

Acute bacterial endometritis = neutrophils
Chronic endometritis = lymphocytes/macrophages
Fungal endometritis = eosinophils
Uro-/pneumovagina = eosinophils

Degree of fibrosis (# layers of fibrous tissue)

Grading categories = I (normal/healthy) – III (sever inflamm/diffuse fibrosis)

Question 19

What special procedures may be undertaken & why?

Answer 19

Hysteroscopy = inspect/remove uterine cysts
Starch granule test = oviduct patency (blockage rare)
Blood samples
- serology = Ab tests (EVA/EIA/EHV-3)
- serum P4/eCG/oestrone sulfate
- heparin sample = karyotyping
- plasma sample = granulose cell tumours (inhibin/testosterone levels)

Question 20

When should endometrial swabs be taken? why? What measures are taken to maintain uterine health?

Answer 20

Sample in dioestrous (>d5 post-OV)

• in health = sterile uterus
• P4 dominance = anti-inflame state > best time to Dx endometritis

Anti-inflammatory state = high risk of iatrogenic infection > TF follow vaginal exam w PGF2a (IM) to induce luteolysis
- CL only responsive to PGF2a from d5 post-OV