Preparing Your Mare for Breeding

1. Preparing Your Mare for Breeding Dr. John Henton University of TennesseeCollege of Veterinary Medicine

2. Review of Basic Reproductive Physiology

3. Seasonal Effects on Mares Seasonally polyestrous Winter Anestrous 50-150 days Affected by geographic latitude Inactive ovaries Cervix relaxed & pale Mare reacts indifferently to stallion

4. Seasonal Effects Spring Transition Estrus without ovulation Estrus activity erratic Longs period of estrus without ovulation Hormonal activity erratic High levels of FSH Low levels of LH

5. Physiologic Breeding Season April – September 95% of mares have normal cyclesand ovulate Hormonal events are very predictable Fertility is highest potential

6. Fall Transition Extended cycles Large non-ovulatory follicles “Autumn Follicles”

7. OperationalBreeding Season Traditional February – June Tennessee WalkingHorse Year around excepttwo weeks around“The Celebration”

8. Photoperiod Management Artificial light at end of day: Start mid November - early December 16 hours 200 watt bulb

9. Photoperiod Management 35 days starts cyclicity from anestrous Still has transitional period Increases effectiveness of other treatments Drugs PGF2 , Progesterone, etc Not proven as effective to lengthen Fall Breeding season

10. General Comments on Mare Management Maiden Mare: Mare which has never foaled What was her job? Why is she now a brood mare? Does she have any chronic non- Reproductive problems? Age Old mares which have never foaled have increases in early embryonic death.

11. General Comments on Mare Management Reproductive Exam: Assure normal reproductive tract. Rectal exam with ultrasound Vaginal exam –speculum & manual Examine cervix Break hymen

12. Maiden Mare Examination of Cervix

13. Vaginal Abnormalities Persistenthymen

14. Vaginal Abnormalities Persistent medial septum Cervical adhesions

15. Maiden Mare cont. Let Down: Mares from highly athletic backgrounds need time to adjust to life as a brood mare Let effects of drugs be removed from her system Anabolic steroids Drugs to suppress estrus

16. Maiden Mare Cont. Natural Breeding Need to intensify teasing May be difficult to detect estrus Jump with teaser

17. Dry or Barren Mares Mare which has foaled previously but is not currently in foal Why is she barren? Did not conceive last breeding season? Was not bred

18. Barren Mares Needs complete Breeding Soundness Examination PRIOR TO THE BREEDING SEASON!!!!! Rectal examination with ultrasound Vaginal examination speculum & manual

19. Vaginal Abnormalities Urine pooling Lacerations or scars of the cervix

20. Barren Mare If BSE indicate any problems Treatment can be complete prior to breeding season. Fall in traditional breeding seasons

21. Wet Mares Mare with nursing foal at her side Exam mare 1 day & 8 days after foaling First estrus after foaling 7-12 days

22. Foal Heat Breeding Henton’s Criteria for Foal Heat Breeding Good foaling history Normal foaling, no retained fetal membranes etc Normal Rectal Examination Follicle of adequate size Adequate uterine involution No hematoma (broad ligament –uterine wall)

23. Foal Heat Breeding Henton’s Criteria: Normal vaginal speculum examination No bruising of cervix or vagina No fluid in anterior vagina No vaginal discharge At least 9 days post foaling Mares bred earlier have high incidence of early embryonic death

24. Foal Heat Breeding If mare meets criteria- Most mares will have same conception rate as mares bred later If mare does not meet criteria- Wait until next normal estrus 30 days post foaling Wait 1 week and short cycle Give prostaglandin

25. Wet Mares Difficult to detect estrus Teasing with stallion Important in natural breeding Protective of their foals Remove foal Twitch mare and tease

26. Preparing Your Marefor Breeding Pre-breeding examination: If maiden or barren Rectal examination with ultrasound Identify and record uterine cysts Make sure not be confused with pregnancy Vaginal examination speculum & manual Know when to expect estrus next estrus

27. Preparing Your Marefor Breeding Get requirements of breeding farm Uterine Culture Negative culture required by some farms prior to breeding Some require statement by a veterinarian that mare appears “ reproductive healthy” Need to correlate palpation, ultrasound, culture, & cytology

28. Guarded Culture Instruments

29. Types of Equine Breeding Today

30. Traditional Breeding Farm

31. Natural breeding or artificial insemination Pre & post breeding management determined by farm staff & their veterinarian Mares usually return home after determined to be pregnant 18-35 days

32. Predict ovulation Detect abnormalities Pregnancy diagnosis Usually every day or every other day while in heat

33. All mares in estrus All mares which should be in estrus 8-10 days post foaling and not teasing Mares which foaled 28-30 days ago and are not teasing and were not bred on the first post partum estrus (Foal Heat) Mares which have been on the farm for more than 30 days and have not teased

39. 14-18 days post breeding Ultrasound and characteristic change in uterine and cervical tone Ultrasound mares with history of twining before 18 days Non twining mares Ultrasound at 18 days post breeding Should be in estrus if not bred Have time to rebred if not pregnant

40. 30 - 40 days post breeding A significant percentage of mares have early embryonic death and will not be pregnant Fall Identify mares which have lost their pregnancies Give enough time to perform diagnostic work up and prepare for breeding early next season Uterine culture and biopsy Adjust weight if necessary Have mare loss weight and then have increasing nutrition during breeding season

41. Ultrasound Uterus Pregnancy DX 10-14 days Edema of uterine folds Fluid Cysts

43. Endometral cysts: often confused with pregnancy

44. Breeding with Fresh Chilled or Frozen Semen

45. Mare usually stays at home May be in local veterinary facility for short time For rectal palpations and prediction of ovulations Insemination

46. Advantages: No shipment of mares/foals to breeding farms Less exposure to disease & injury Increases stallion selection

47. Disadvantages: Not all stallions tolerate chilling of their semen Poor conception rates as compared to natural or AI breeding

48. No teaser available Frequent palpations Hormonal synchronization Know when she should be in estrus

49. Loss of control by breeding farm Assuring proper parentage Semen bred to correct mare Semen from correct stallion Most breeds require DNA testingof foal

50. Availability of semen on dates needed Many farms collect Mon.,Wed., & Fri. Holidays and Mondays are difficult Expensive Many rectal palpations(trip charges?)

51. Procedure for Breeding with Fresh Shipped Semen Predict ovulation Mare is rectally palpated daily often with assistance of ultrasound When the mare is determine to likely ovulate within 48 hours The semen is ordered The goal is to breed 12-24 hours before ovulation

52. Determines motility & concentration Extends semen Ships at least 1 billion spermatozoa

53. Containers especially made to control rate of cooling & protect semen form temperature shock Cool to 40°F or 4°C Equitainer Disposable

54. Chilled semen is placed in the mare’s uterus Gradual warming A small portion is saved to check motility of extended semen The mare is palpated daily to assure ovulation

55. If ovulation does not occur, reorder semen for shipment

56. External Examination Conformation Croup & rump High tail head Urine pooling vulvar lips Straight up & down Tight vulvar sphincter “Wind sucking test”

57. Causes of Bacterial Endometritus Recessed anus Old-thin mares Treat-caslicks Abnormal anatomy Poor perineal conformation Tilted vulva

60. External Exam Exudates Tail Vulvar lips Between legs

63. Problem Mares

64. Early Embryonic Death

65. Early Embryonic Death Mares conceive and lose the pregnancy before 40 days Many times associated with endometrial fibrosis Older mares Treat with supplement progesterone Low grade infection

66. Delayed Uterine Clearance Mares unable to evacuate uterus More motility Especially after breeding Chronic inflammation Treat with large volume uterine lavages Before and after breeding

67. The End