Equine Andrology

Question 1

reasons for performing a BSE

Answer 1

• prepurchase
• before the breeding season
• problem

Question 2

history of breeding stallion

Answer 2

• athletic background
• physical health
• breeding history
  
  • program type
  • pregnancy rates
  • management
  • vaccinations

Question 3

physical exam for BSE

Answer 3

• identification
• TPR
• eyes (see stimuli)
• legs
• mouth
• respiratory system, cardio
• body condition
• possible heritable conditions
• reproductive tract

Question 4

BSE Classification

Answer 4

satisfactory

questionable

unsatisfactory

Question 5

satisfactory breeding prospect

Answer 5

• free of venereal pathogens
• ≥60% progressively motile sperm (not general)
• ≥60% morphologically normal sperm
• ≥ 1 billion progressively motile, morphologically normal sperm of second ejaculate
• natural service book (40 mares)
• AI book (120 mares)

Question 6

physical examination of reproductive tract

Answer 6

• preliminary assessment of external genitalia
  
  • before semen collection
• thorough examination
  
  • penis- after sexual arousal; before washing
  • testes and accessory sex glands
    
    • after semen collection

Question 7

penile abnormalities

Answer 7

• trauma
• paraphimosis
• penile paralysis
• priapism (can’t withdraw penis due to prolonged erection)
• tumors (usually SCC)
• habronemiasis
• infections

Question 8

paraphimosis

Answer 8

• inability to retract penis back to the prepuce
• various causes
  
  • trauma
  • inflammation
  • phenothiazine tranquilizers (acepromazine not recommended)

Question 9

treatment of paraphimosis

Answer 9

• replacing penis into prepucial cavity
• hydrotherapy
• massage
• local ointments
• abx
• NSAIDs

Question 10

Habronemiasis and SCC of penis

Answer 10

• perform penile exam after sexual arousal
• to differentiate, must biopsy

Question 11

evaluation of stallion’s sexual behavior

Answer 11

• during semen evaluation, or separate
• receptive to estrous mare
• gentle handling
• “friendly environment”
• precopulatory responses
• copulation
• ejaculation

Question 12

swabs for bacterial cultures

Answer 12

• pre-wash
  
  • prepuce
  • body of penis
  • fossa glandis
• post-wash
  
  • urethra
• post-ejaculation
  
  • urethra
  • semen

Question 13

local bacerial infectious

Answer 13

• bacteria that may cause venereal diseases
  
  • Pseudomonas aeruginosa
  • Klebsiella pneumoniae
  • Taylorella equigenitalis (CEM-reportable disease)

Question 14

semen collection

Answer 14

• collect 2 samples approximately 1 hour apart
  
  • 2nd ejaculate should have 1/2 # of sperm compared to first ejaculate

Question 15

methods and equipment for semen collection in stallion

Answer 15

• artificial vagina (Colorado, Missouri)
• condom
• manual stimulation
• pharmacologically induced
• mount source
  
  • jump mare
  • phantom

Question 16

stallion semen evaluation

Answer 16

• volume
• color (and smell)
  
  • abnormal= whole milk color, watery, pink
• +/- pH
• motility
• concentration
• morphology

Question 17

evaluation of motility of equine sperm

Answer 17

• total (%)
• progressive (%)
• velocity (1-4)
  
  • ≥ 60% progressive

Question 18

determining concentration of sperm

Answer 18

• number of sperm in 1 mL of semen
• hemocytometer
• spectrophotometer
• nucleocounter
• total sperm number (10⁹) = volume (mL) x concentration (10⁶ sperm/mL)
  
  • depends on testicular volume
  • correlates with total scrotal width (not circumference)
  • average value= 6 billion sperm

Question 19

evaluate sperm morphology in stallion

Answer 19

• ≥ 60% normal
• various methods
  
  • phase-contrast
  • eosin-nigrosin
  • diff quick
• sperm defects
  
  • individual defects %

Question 20

evaluation of stallion scrotum

Answer 20

• visual inspection
• palpation
• ultrasound evaluation
• testicular boipsy
• aspiration cytology

Question 21

visual inspection stallion scrotum

Answer 21

• symmetry
• shape
• integrity of skin

Question 22

palpation of stallion scrotum

Answer 22

• presence of both scrotal testes
• texture
• sensitivity
• local temperature
• mobility within vaginal cavity
• location of tail of epididymis
• presence of palpable abnormal structures

Question 23

measuring stallion scrotum

Answer 23

• calipers, ultrasound
• total scrotal width
  
  • correlated with volume of testicular parenchyma
  • correlated with sperm production capacity
  • concern when less than 8 cm
• all dimensions of testes (width, height, length)
  
  • ​testicular volume can be calculated-correlated with daily sperm output

Question 24

scrotal abnormalities

Answer 24

• enlarged scrotum
  
  • torsion of spermatic cord
  • hernia
  • testicular tumor (seminoma)
  • periorchitis
  • hydrocele

Question 25

torsion of spermatic cord ≤ 180˚

Answer 25

• no clinical signs
• still fertile, blood flow still good

Question 26

torsion of spermatic cord >180˚

Answer 26

• severe colic
• scrotal swelling
• testicular ischemia
• negative effects on contralateral testis
• treatment
  
  • ​surgical

Question 27

inguinal/scrotal hernia

Answer 27

• intestines enter the vaginal cavity through the vaginal ring
• predisposing factors
  
  • enlarged vaginal ring
  • breeding
  • exercise
  • transport

Question 28

diagnosis & treatment of inguinal/scrotal hernia

Answer 28

• dx
  
  • rectal palpation
    
    • inguinal rings
  • ultrasound evaluation
    
    • intestines in vaginal cavity
• tx
  
  • surgical
  • castration recommended (hereditary?)

Question 29

stallion internal genitalia

Answer 29

• vas deferens: ampulla
• vesicular gland
• prostate gland
• bulbourethral gland

Question 30

occluded ampullae

Answer 30

• incidence: rare
• etiology
  
  • unknown
    
    • individual predisposition: “sperm accumulators”
    • low frequency of ejaculations
  • physical causes
    
    • cystic abnormalities

Question 31

clinical signs of occluded ampullae

Answer 31

• azoospermia (no sperm in ejaculate)
• large numbers of tailess sperm heads

Question 32

diagnosis of occluded ampullae

Answer 32

• rectal palpation
  
  • prominent ampullae
• ultrasound evaluation
  
  • enlarged lumen of ampullae
  • hyperechoic content in terminal parts of deferent ducts

Question 33

treatment of occluded ampullae

Answer 33

• manual massage per rectum
• administration of oxytocin before ejaculation
• frequent ejaculation

Question 34

seminal vesiculitis

Answer 34

• incidence: rare
• etiology
  
  • bacterial infection
    
    • Klebsiella aeruginosa
    • Pseudomonas pneumoniae
    • Streptococcus zooepidemicus

Question 35

clinical signs of seminal vesiculitis

Answer 35

• infertility
• poor semen quality
• pyospermia
• hemospermia

Question 36

diagnosis of seminal vesiculitis

Answer 36

• clinical signs
• inflammatory cells in semen
• positive culture results
• +/- urethroscopy

Question 37

treatment of seminal vesiculitis

Answer 37

• endoscopic lavage of vesicular glands
• endoscopic infusion of abx into vesicular glands lumen
• systemic abx +/- enrofloxacin

Question 38

testing for Equine Viral Arteritis

Answer 38

• serum neutralization or complement fixation
  
  • blood serum
• virus isolation or detection of viral nucleic acid
  
  • semen

Question 39

what does a BSE actually assess?

Answer 39

• fertility potential only, not actual fertility
• test results are only valid for the day of the exam
• cannot be used to guarantee what the animal will do in the future