Artificial Insemination

Question 1

What is Artificial Insemination? How much sperm is needed for successful AI of a mare?

Answer 1

• Deposition of an adequate number of progressively motile, morphologically normal, live sperm into the mare’s uterus at the optimal time

Question 2

How is semen processed for cooled storage?

Answer 2

• Following collection examine”
  
  • motility
  • concentration
  • Morphology
  • Determine PMMNS
• Dilute in a semen extender
  
  • dilute seminal plasma
  • Buffer to maintain pH
  • Energy source for spermatozoa (glucose)
  • antibiotics (penicillin, ticarcillin, amikacin, gentamicin)
  • Lipids in milk or egg yolk
    
    • stabilize sperm membrane during colling
    • prevent cold shock

Question 3

What is the purpose of semen extenders?

Answer 3

• prolong the life of the sperm
• protect sperm from the environment
• increase volume of the inseminate
• Permit antibiotic treatment of semen

Question 4

What temperature does semen need to be kept at when shipping?

Answer 4

4-6C

Question 5

When should the mare be bred with the different options (live cover, fresh semen, chilled semen, frozen semen)

Answer 5

• Follow mare closely to monitor follicle progression and predict ovulation
  
  • palpate and US daily to every other day
  • Follicles grow 3-5mm per day
  • Induce ovulation when follicle is ≥35 mm with uterine edema
  • Record findings
  • Monitor for fluid, air, cysts
• Natural service / fresh semen: w/in 48hrs prior to ovulation
• Fresh chilled semen: w/in 24-48hrs prior to ovulation
• Frozen semen: w/in 6hrs pre-ovulation or 6hrs post-ovulation
• Oocyte is viable for ~12hrs post-ovulation

Question 6

What are the criteria for breeding consideration

Answer 6

• ≥35mm follicle
• Mare ‘broken down’ if can tease
• Peak or waning uterine edema pattern
• softening cervix

Question 7

What are the signs of impending ovulation?

Answer 7

• Follicle becomes soft and may be painful on palpation
• Shape of follicle starts to change
• Change in wall character
• Increased echogenicity of follicular fluid
• Uterine edema pattern waning

Question 8

Describe the process of mare management when breeding with Fresh cooled semen?

Answer 8

• Once follicle is ≥35mm and the mare is in estrus:
  
  • call for semen collection and shipment
  • administer hCG or deslorelin once collection and shipment are confirmed
    
    • When semen arrive the next day breed the mare
  • OR Administer hCG or deslorelin when semen arrives and breed the mare
• Monitor post-breeding for PMIE and until ovulation

Question 9

What determines the fertility of cooled semen

Answer 9

• Target dose 500 million to 1 billion PMS
• Semen quality
• Timing of insemination
• Semen extender
• Proper dilution ratio based on extender used
  
  • ≥1:3 for most
  • ≥1:2 for INRA 96
• Cooling Rate
  
  • 0.05 - 0.1C/minute to desired temperature of 4-6C
• Shipping container and ambient temperature

Question 10

How should mares be managed when breeding with frozen semen?

Answer 10

• Examine the mare EOD until dominate follicle is about 35 mm then examine daily
• One follicle ≥ 35 mm and the mare is in estrus
  
  • Induce ovulation
• Option 1
  
  • Ultrasound every 6 hours
  • Inseminate w/in 6 hrs post-ovulation
• Option 2
  
  • inseminate 24-30 and 40 hrs after inducing ovulation
• Technique:
  
  • traditional insemination technique
  • Deep horn insemination techniqu