Equine Reproductive Procedures

Equine Reproductive Procedures is a user-friendly guide to reproductive management, diagnostic techniques, and therapeutic techniques on stallions, mares, and foals.  Offering detailed descriptions of 161 procedures ranging from common to highly specialized, the book gives step-by-step instructions with interpretative information, as well as useful equipment lists and references for further reading. Presented in a highly portable spiral-bound format, Equine Reproductive Procedures is a practical resource for daily use in equine practice.

Divided into sections on the non-pregnant mare, the pregnant mare, the postpartum mare, the stallion, and the newborn foal, the book is well-illustrated throughout with clinical photographs demonstrating procedures.  Equine Reproductive Procedures provides practical guidance for performing basic and advanced techniques associated with the medical management of horses.

• Language: English
• Publisher: Wiley
• Release date: Jun 23, 2014
• ISBN: 9781118813829

Book preview

Table of Contents

Cover

Title Page

Copyright

List of Contributors

Preface

Section I: Non-Pregnant Mare

Chapter 1: Reproductive Evaluation of the Mare

Introduction

Examination Technique

Other Tests

Additional Comments

Further Reading

Chapter 2: Teasing

Introduction

Technique

Additional Comments

Further Reading

Chapter 3: Tail Wrap and Preparation/Washing of the Perineum

Introduction

Placement of a Tail Wrap

Washing Perineum Technique

Interpretation

Chapter 4: Placement of a Tail Rope

Introduction

Technique for Tying a Tail Rope

Technique for Using an Elastic Cord to Tie the Mare's Tail to the Stocks

Further Reading

Chapter 5: Perineal Conformation Evaluation

Introduction

Technique

Interpretation

Chapter 6: Removal of a Persistent Hymen

Introduction

Technique

Interpretation

Chapter 7: Palpation of the Reproductive Tract of the Non-Pregnant Mare

Introduction

Palpation Technique

Additional Comments

Further Reading

Chapter 8: Ultrasound Evaluation of the Non-Pregnant Mare

Introduction

Technique

Interpretation

Further Reading

Chapter 9: Prediction of Ovulation

Introduction

Technique

Further Reading

Chapter 10: Speculum Examination of the Vagina

Introduction

Technique

Interpretation

Further Reading

Chapter 11: Digital Examination of the Vagina/Cervix

Introduction

Stage of Cycle

Technique

Interpretation and Additional Comments

Further Reading

Chapter 12: Uterine Culture Collection: Swab/Brush

Introduction

Technique

Interpretation

Further Reading

Chapter 13: Antimicrobiotic Sensitivity Testing

Introduction

Technique

Further Reading

Chapter 14: Microbiology: Microbial Culture

Introduction

Technique

Further Reading

Chapter 15: Microbiology: Gram Stain

Introduction

Technique

Interpretation

Further Reading

Chapter 16: qPCR Assay for the Diagnosis of Infectious Endometritis

Introduction

Sample Collection Technique

qPCR and DNA Sequencing: The Basics

Interpretation of qPCR Data

Additional Comments

Further Reading

Chapter 17: Uterine Cytology Collection: Swab/Brush

Introduction

Technique

Interpretation

Further Reading

Chapter 18: Uterine Culture/Cytology: Low Volume Lavage

Introduction

Technique

Interpretation

Further Reading

Chapter 19: Endometrial Biopsy

Introduction

Technique

Biopsy Interpretation

Chapter 20: Hysteroscopic Examination of the Uterus

Introduction

Technique

Additional Comments

Further Reading

Chapter 21: Endometrial Cyst Removal

Introduction

Techniques

Interpretation

Further Reading

Chapter 22: Chromosomal Analysis

Introduction

Technique

Additional Comments

Chapter 23: Endocrinological Examination

Introduction

Technique

Interpretation

Further Reading

Chapter 24: Laparoscopic Examination of the Uterus and Ovaries

Introduction

Technique

Further Reading

Chapter 25: Evaluation of the Mammary Gland

Introduction

Techinque

Further Reading

Chapter 26: Antisperm Antibody Testing

Introduction

Techniques

Additional Comments

Further Reading

Chapter 27: Starch Granule Test for the Evaluation of Oviductal Patency

Introduction

Technique

Additional Comments

Further Reading

Chapter 28: Fluorescent Microspheres Test for Evaluation of Oviductal Patency

Introduction

Transvaginal Ultrasound Technique

Laparoscope Technique

Additional Comments

Further Reading

Chapter 29: Oviductal Flush Procedure for the Evaluation of Oviductal Patency

Introduction

Retrograde Oviductal Flush Technique

Normograde Oviductal Flush (Laparotomy Approach) Technique

Normograde Oviductal Flush (Laparoscopic Approach) Technique

Chapter 30: Prostaglandin E2 Treatment for Blocked Oviducts

Introduction

Technique

Additional Comments

Chapter 31: Uterine Lavage

Introduction

Technique

Interpretation

Further Reading

Chapter 32: Uterine Infusion

Introduction

Technique

Interpretation

Further Reading

Chapter 33: Restraint for Breeding

Introduction

Technique

Interpretation

Chapter 34: Natural Service: Pasture Breeding

Introduction

Pasture Breeding Programs

Further Reading

Chapter 35: Natural Service: In-hand Breeding

Introduction

Technique

Additional Comments

Further Reading

Chapter 36: Breeding Stitches

Introduction

Technique

Additional Comments

Further Reading

Chapter 37: Reinforcement Breeding

Introduction

Technique

Additional Comments

Further Reading

Chapter 38: Breeding with Fresh or Cooled Semen

Introduction

Pre-Insemination Technique

Insemination Technique

Interpretation

Further Reading

Chapter 39: Insemination Through a Vaginal Speculum

Introduction

Technique

Additional Comments

Further Reading

Chapter 40: Breeding with Frozen Semen

Introduction

Administration of an Ovulation Induction Agent

Management Strategy with One Dose of Semen Available per Cycle

Management Strategy with Two Doses of Semen Available per Cycle

Breeding Technique

Interpretation

Further Reading

Chapter 41 41: Deep Horn Insemination

Introduction

Technique

Interpretation

Further Reading

Chapter 42: Hysteroscopic (Low Dose) Insemination

Introduction

Technique

Additional Comments

Further Reading

Chapter 43: Caslick Operation or Vulvoplasty

Introduction

Initial Stage of Technique

Temporary Staple Technique

Comments on the Staple Technique

Permanent Suture Technique

Comments on the Surgical Technique

Further Reading

Chapter 44: Contagious Equine Metritis Testing

Introduction

Mare Diagnosis

Mare Treatment

Stallion Diagnosis

Stallion Treatment

Further Reading

Chapter 45: Management of Seasonal Anestrus: Artificial Photoperiod

Introduction

Technique

Additional Comments

Further Reading

Chapter 46: Management of Seasonal Anestrus: Hormone Therapy

Introduction

Technique

Additional Comments

Further Reading

Chapter 47: Hormone Therapy in Cycling Mares

Introduction

Gonadotropin-Releasing Hormone and GnRH Agonists

Human Chorionic Gonadotropin

Follicle-Stimulating Hormone

Progesterone and Progestins

Estrogens

Prostaglandins

Oxytocin

Dopamine Antagonists (Domperidone and Sulpiride)

Further Reading

Chapter 48: Estrus Suppression

Introduction

Technique

Additional Comments

Further Reading

Chapter 49: Use of an Intrauterine Ball in Estrus Suppression

Introduction

Technique of Intrauterine Ball Placement

Technique of Intrauterine Ball Removal

Interpretation

Chapter 50: Harvesting and Shipping Ovaries for Oocyte Recovery

Introduction

Technique

Further Reading

Section II: Pregnant Mare

Chapter 51: Embryo Collection

Introduction

Flush Procedure

Embryo Search

Extra Flush Procedure

Washing the Embryo

Interpretation

Futher Reading

Chapter 52: Embryo Evaluation

Introduction

Developmental Stages

Embryo Grading

Determination of Embryo Size

Further Reading

Chapter 53: Embryo Biopsy

Introduction

Technique

Further Reading

Chapter 54: Embryo Packaging for Cooled Transport

Introduction

Technique for Packaging Embryos for Cooled Transport

Technique for Receiving and Handling a Shipped Embryo

Additional Comments

Further Reading

Chapter 55: Embryo Cryopreservation

Introduction

Vitrification Technique

Warming (Thawing) and Transfer Technique

Additional Comments

Chapter 56: Non-Surgical Embryo Transfer

Introduction

Transfer Technique

Management of the Recipient Mare After Transfer

Additional Comments

Further Reading

Chapter 57: Palpation of the Pregnant Mare Per Rectum

Introduction

Technique

Interpretation and Additional Comments

Further Reading

Chapter 58: Ultrasound Examination of the Pregnant Mare

Introduction

Technique

Interpretation and Additional Comments

Further Reading

Chapter 59: Speculum Examination of the Pregnant Mare

Introduction

Technique

Interpretation

Additional Comments: Potential Risks

Further Reading

Chapter 60: Ultrasound Determination of Fetal Sex

Introduction

Technique: 55–90 Days of Gestation

Technique: 90–150 Days of Gestation

Technique: After 150 Days of Gestation

Interpretation

Chapter 61: Assessment of Fetal Well-being

Introduction

Technique

Interpretation

Chapter 62: Combined Thickness of the Uterus and Placenta

Introduction

Technique

Interpretation and Additional Comments

Chapter 63: Doppler Ultrasonography

Introduction

Technique for Assessing a Pregnant Mare and Fetus

Technique for Assessing a Stallion

Technique for Assessing Ovaries

Further Reading

Chapter 64: Prediction of Fetal Age

Introduction

Embryo Characteristics

Chapter 65: Twin Reduction: Manual Technique

Introduction

Technique

Additional Comments

Further Reading

Chapter 66: Twin Reduction: Transvaginal Aspiration

Introduction

Technique

Interpretation

Further Reading

Chapter 67: Twin Reduction: Cranio-Cervical Dislocation

Introduction

Technique

Interpretation

Additional Comments

Further Reading

Chapter 68: Twin Reduction: Transabdominal Fetal Cardiac Puncture

Introduction

Technique

Interpretation

Further Reading

Chapter 69: Elective Termination of Pregnancy

Introduction

Technique

Other Methods to Terminate an Equine Pregnancy

Interpretation

Further Reading

Chapter 70: Abortion Diagnostic Evaluation: Sample Collection in the Field and Submission

Introduction

Technique

Submission Protocols

Samples for Submission

Further Reading

Chapter 71: Endocrine Evaluation of Pregnancy

Introduction

Hormonal Tests for Pregnancy

Additional Comments

Chapter 72: Treatment of Vaginal Varicosities

Introduction

Technique for Endoscopic Examination

Technique for Laser Photocoagulation of Varicosities Using an Nd:YAG Laser

Interpretation

Chapter 73: Manual Correction of Uterine Torsion

Introduction

Technique for Manual Rotation of the Uterus Through the Cervix

Technique for Rolling (Plank in the Flank)

Interpretation

Further Reading

Chapter 74: Preparation of the Mare for Foaling

Introduction

Technique

Interpretation

Further Reading

Chapter 75: Assessment of Mammary Gland Secretions to Predict Foaling

Introduction

Technique

Further Reading

Chapter 76: Assessment of pH of Mammary Gland Secretions to Predict Foaling

Introduction

Technique

Additional Comments

Further Reading

Chapter 77: Monitoring of Peri-Parturient Mares Using Video and Web Cameras

Introduction

Wired Camera Systems

Wireless Camera Systems

Internet/Web-Based Camera Systems

Interpretation

Chapter 78: Foaling Alert: Vulvar Device

Introduction

Technique

Interpretation

Further Reading

Chapter 79: Positional Labor Alert Devices

Introduction

Halter Devices

Halter Device Technique

Girth Device Technique

Interpretation

Further Reading

Chapter 80: Induction of Parturition

Introduction

Technique

Interpretation

Further Reading

Chapter 81: Premature Separation of the Placenta

Introduction

Technique

Additional Comments

Further Reading

Chapter 82: Dystocia Management

Introduction

Technique

Additional Comments

Further Reading

Chapter 83: Dystocia Correction

Introduction

Technique

Further Reading

Chapter 84: Fetotomy

Introduction

Fetotomy Instruments

Technique

Specific Fetotomy Cuts

Interpretation

Further Reading

Chapter 85: Epidural

Introduction

Technique

Interpretation

Further Reading

Chapter 86: Induction of Lactation to Create a Nurse Mare

Introduction

Technique

Additional Comments

Further Reading

Chapter 87: Screening the Pregnant Mare to Prevent Neonatal Isoerythrolysis

Introduction

Technique

Additional Comments

Further Reading

Section III: Postpartum Mare

Chapter 88: Evaluation of Colostrum Specific Gravity

Introduction

Technique

Interpretation

Further Reading

Chapter 89: Evaluation of Colostrum Quality: Brix Refractometry

Introduction

Technique

Interpretation and Additional Comments

Further Reading

Chapter 90: Colostrum Banking

Introduction

Technique

Interpretation and Additional Comments

Further Reading

Chapter 91: Obtaining Milk from the Mare

Introduction

Hand Milking Technique

Milk Pump Technique

Comments

Further Reading

Chapter 92: Placental Evaluation

Introduction

Technique

Interpretation and Additional Comments

Further Reading

Chapter 93: Removal of Retained Placenta

Introduction

Technique

Interpretation

Further Reading

Chapter 94: Abdominocentesis in the Postpartum Mare

Introduction

Technique

Interpretation

Further Reading

Chapter 95: Uterine Prolapse Treatment

Introduction

Immediate Prolapse Treatment

Technique for Replacing a Uterine Prolapse

Interpretation

Further Reading

Chapter 96: Buhner Needle Placement of a Perivulvar Suture

Introduction

Technique

Interpretation

Section IV: Stallion

Chapter 97: Breeding Soundness Evaluation of the Stallion

Introduction

Examination Technique

Other Tests

Interpretation and Additional Comments

Chapter 98: Training of a Stallion to Use a Phantom

Introduction

Technique

Interpretation

Further Reading

Chapter 99: Missouri Artificial Vagina

Introduction

Technique

Interpretation

Further Reading

Chapter 100: Colorado Model Artificial Vagina

Introduction

Technique for Assembly of the Colorado Model Artificial Vagina

Additional Comments

Further Reading

Chapter 101: Roanoke Artificial Vagina

Introduction

Technique

Interpretation

Further Reading

Chapter 102: Hannover Artificial Vagina

Introduction

Technique

Additional Comments

Further Reading

Chapter 103: Teaser Stallions

Introduction

Technique

Additional Comments

Further Reading

Chapter 104: Standing Semen Collection

Introduction

Technique

Interpretation

Further Reading

Chapter 105: Chemical Ejaculation

Introduction

Technique

Additional Comments

Further Reading

Chapter 106: Preparation of a Jump Mare or a Mare for Natural Cover

Introduction

Technique

Interpretation

Chapter 107: Washing the Penis

Introduction

Technique

Interpretation

Further Reading

Chapter 108: Evaluation of Sexual Behavior in the Stallion

Introduction

Evaluation of Sexual Behavior

Further Reading

Chapter 109: Calibrated Spectrophotometer Evaluation of Sperm Concentration

Introduction

Technique Using a Spectrophotometer

Technique Using a Photometer

Interpretation

Further Reading

Chapter 110: Hemocytometer Evaluation of Sperm Concentration

Introduction

Technique

Interpretation

Further Reading

Chapter 111: NucleoCounter® Evaluation of Sperm Concentration and Viability

Introduction

Technique

Additional Comments

Further Reading

Chapter 112: Visual Evaluation of Sperm Motility

Introduction

Technique

Additional Comments

Further Reading

Chapter 113: Computer-Assisted Sperm Analysis

Introduction

Technique

Interpretation

Additional Comments

Further Reading

Chapter 114: Eosin-Nigrosin Staining in the Evaluation of Sperm

Introduction

Semen Staining Technique

Semen Smearing Technique

Interpretation

Further Reading

Chapter 115: Evaluation of Sperm Morphology

Introduction

Technique

Classification of Sperm Abnormalities

Abnormal Sperm Morphology

Interpretation

Additional Comments

Further Reading

Chapter 116: Determination of Daily Sperm Output

Introduction

Technique

Additional Comments

Chapter 117: Measurement of Testicular Size and Estimation of Daily Sperm Output

Introduction

Technique

Interpretation

Chapter 118: Wet Mount Evaluation of Sperm

Introduction

Preparation of a Wet Mount

Differential Interference Contrast Microscopy

Phase-Contrast Microscopy

Interpretation

Further Reading

Chapter 119: Diff-Quik® Evaluation of Round Cells and Sperm

Introduction

Technique to Assess Round Cells

Technique to Assess Spermatozoa

Rinsing of Slides

Interpretation

Further Reading

Chapter 120: Electron Microscopy of Semen

Introduction

Technique

Additional Comments

Further Reading

Chapter 121: Bacterial Culture in the Stallion

Introduction

Technique for Culturing a Stallion's External Genitalia

Technique for Culturing Fresh Cooled Semen

Technique for Culturing Frozen Semen

Interpretation

Further Reading

Chapter 122: Evaluation of pH and Osmolarity of Semen

Introduction

Technique

Additional Comments

Further Reading

Chapter 123: Alkaline Phosphatase: A Marker for Ejaculation

Introduction

Technique

Interpretation

Chapter 124: Diagnosis and Management of Urospermia

Introduction

Testing for Urospermia

Technique for the Management of Urospermia

Interpretation

Further Reading

Chapter 125: Semen Extenders and Sperm Media

Semen Extenders

Sperm Media

Chapter 126: Preparation of Semen for Cooled Transport

Introduction

Technique

Interpretation

Further Reading

Chapter 127: Packing Semen for Cooled Transport

Introduction

Technique

Interpretation

Further Reading

Chapter 128: Longevity Testing of Sperm

Introduction

Technique

Additional Comments

Further Reading

Chapter 129: Calculation of g Force for Centrifuging Semen

Introduction

Technique

Reference

Chapter 130: Centrifugation of Semen: Standard Technique

Introduction

Technique

Interpretation

Further Reading

Chapter 131: Centrifugation of Semen: Cushion Technique

Introduction

Technique

Additional Comments

Further Reading

Chapter 132: Centrifugation of Semen: Selection of Motile Sperm Using a Single Layer Colloid Technique

Introduction

Technique

Interpretation

Further Reading

Chapter 133: Semen Freezing

Introduction

Technique for Loading Straws with Extended Semen

Technique for Freezing Straws of Extended Semen

Additional Comments

Further Reading

Chapter 134: Thawing Frozen Semen

Introduction

Technique

Interpretation

Further Reading

Chapter 135: Preparing a Vapor Shipper

Introduction

Disinfection Technique

Filling Technique

Interpretation

Further Reading

Chapter 136: Loading a Vapor Shipper

Introduction

Technique

Interpretation

Further Reading

Chapter 137: Maintaining a Long-Term Frozen Semen Storage Tank

Introduction

Technique

Interpretation

Further Reading

Chapter 138: Harvesting and Shipping Testes

Introduction

Technique

Interpretation

Further Reading

Chapter 139: Epididymal Sperm Recovery

Introduction

Technique

Alternative Seminal Plasma Processing

Interpretation

Further Reading

Chapter 140: Endoscopic Examination of the Urethra

Introduction

Technique

Interpretation

Additional Comments

Further Reading

Chapter 141: Palpation and Ultrasonography of the Testis, Epididymis, and Spermatic Cord

Introduction

Safety and Restraint

Technique

Interpretation

Additional Comments

Further Reading

Chapter 142: Palpation and Ultrasonography of the Accessory Sex Glands

Introduction

Anatomy

Safety and Restraint

Technique

Interpretation

Additional Comments

Further Reading

Chapter 143: Radiographic Examination of the Penis

Introduction

Technique

Additional Comments

Further Reading

Chapter 144: Testicular Biopsy and Aspiration

Introduction

Technique for an Incisional (Wedge) Biopsy

Technique for a Split Needle Biopsy

Technique for Fine Needle Aspiration

Interpretation

Chapter 145: Assessment of Sperm Plasma Membrane Integrity and Viability: Propidium Iodide/SYBR-14

Introduction

Stock Solutions

Technique

Interpretation

Further Reading

Chapter 146: Sperm Chromatin Structure Assay

Introduction

Technique

Interpretation

Further Reading

Chapter 147: Hypo-Osmotic Swelling Test

Introduction

Technique

Additional Comments

Further Reading

Chapter 148: Assessment of Sperm Acrosomal Status: FITC PNA

Introduction

Stock Solutions

Technique

Interpretation

Further Reading

Chapter 149: Assessment of Sperm Mitochondrial Function: JC-1 and Rhodamine 123

Introduction

Stock Solutions

Technique

Interpretation

Further Reading

Chapter 150: Equine Viral Arteritis Testing

Introduction

Technique

Treatment

Outcome and Prognosis

Prevention

Client Education

Chapter 151: Diagnostic Endocrinology: Baseline Hormone Levels

Introduction

Technique

Additional Comments

Further Reading

Chapter 152: Diagnostic Endocrinology: GnRH Stimulation Tests

Introduction

Technique

Additional Comments

Further Reading

Chapter 153: Diagnostic Endocrinology: hCG Stimulation Test

Introduction

Technique

Interpretation

Further Reading

Chapter 154: Diagnostic Endocrinology: Estrogen Conjugate Assay

Introduction

Technique

Additional Comments

Further Reading

Chapter 155: Probang Apparatus

Introduction

Technique

Interpretation

Further Reading

Chapter 156: Support Apparatus for Paraphimosis

Introduction

Technique

Interpretation

Further Reading

Section V: Newborn Foal

Chapter 157: Birth Resuscitation

Introduction

Birth Resuscitation Technique

Additional Comments

Further Reading

Chapter 158: Evaluation of Passive Transfer

Introduction

Technique

Interpretation and Additional Comments

Enzyme Immunoassay

Further Reading

Chapter 159: Colostral Administration via Naso-Gastric Intubation

Introduction

Technique

Interpretation

Further Reading

Chapter 160: Routine Care

Introduction

Technique

Additional Comments

Further Reading

Chapter 161: Foal Rejection

Introduction

Technique

Additional Comments

Further Reading

Section VI: Appendices

Appendix 1: Society for Theriogenology Stallion Reproductive Evaluation Form

Appendix 2: Mare Breeding Soundness Evaluation Form

Appendix 3: Formulary for Equine Reproduction

Appendix 4: Foaling Kit and Associated Equipment and Supplies

Index

End User License Agreement

List of Illustrations

Figure 2.1

Figure 2.2

Figure 3.1

Figure 3.2

Figure 3.3

Figure 3.4

Figure 3.5

Figure 3.6

Figure 3.7

Figure 3.8

Figure 3.9

Figure 3.10

Figure 3.11

Figure 4.1

Figure 4.2

Figure 4.3

Figure 4.4

Figure 4.5

Figure 4.6

Figure 4.7

Figure 4.8

Figure 5.1

Figure 5.2

Figure 5.3

Figure 5.4

Figure 6.1

Figure 6.2

Figure 7.1

Figure 7.2

Figure 7.3

Figure 7.4

Figure 7.5

Figure 7.6

Figure 8.1

Figure 8.2

Figure 8.5

Figure 8.6

Figure 8.9

Figure 8.10

Figure 8.11

Figure 8.12

Figure 9.1

Figure 10.1

Figure 10.2

Figure 10.3

Figure 12.1

Figure 12.2

Figure 12.3

Figure 13.1

Figure 13.2

Figure 14.1

Figure 14.2

Figure 14.4

Figure 14.5

Figure 15.1

Figure 15.2

Figure 16.1

Figure 17.1

Figure 17.2

Figure 17.3

Figure 17.4

Figure 17.5

Figure 17.6

Figure 17.7

Figure 17.8

Figure 17.9

Figure 17.10

Figure 17.11

Figure 18.1

Figure 18.2

Figure 18.3

Figure 19.1

Figure 20.1

Figure 20.2

Figure 20.3

Figure 20.4

Figure 20.5

Figure 20.6

Figure 20.7

Figure 20.8

Figure 21.1

Figure 22.1

Figure 22.2

Figure 22.3

Figure 24.1

Figure 24.2

Figure 24.3

Figure 25.1

Figure 25.2

Figure 25.3

Figure 25.4

Figure 25.5

Figure 25.6

Figure 29.1

Figure 30.1

Figure 31.1

Figure 31.2

Figure 31.3

Figure 31.4

Figure 31.5

Figure 32.1

Figure 32.2

Figure 33.1

Figure 33.2

Figure 33.3

Figure 34.1

Figure 34.2

Figure 35.1

Figure 35.2

Figure 35.3

Figure 36.1

Figure 38.1

Figure 38.2

Figure 38.3

Figure 38.4

Figure 39.1

Figure 39.2

Figure 40.1

Figure 40.2

Figure 40.3

Figure 41.1

Figure 41.2

Figure 42.1

Figure 42.2

Figure 42.3

Figure 42.4

Figure 43.1

Figure 43.2

Figure 43.3

Figure 43.4

Figure 43.5

Figure 43.6

Figure 43.7

Figure 44.1

Figure 44.2

Figure 44.3

Figure 44.4

Figure 44.5

Figure 45.1

Figure 45.2

Figure 47.1

Figure 49.1

Figure 49.2

Figure 49.3

Figure 50.1

Figure 51.1

Figure 51.2

Figure 51.3

Figure 51.4

Figure 51.5

Figure 51.6

Figure 52.1

Figure 52.2

Figure 52.3

Figure 52.4

Figure 52.5

Figure 52.6

Figure 52.7

Figure 53.1

Figure 54.1

Figure 54.2

Figure 54.3

Figure 54.4

Figure 54.5

Figure 55.1

Figure 55.2

Figure 55.3

Figure 55.4

Figure 56.1

Figure 57.1

Figure 58.1

Figure 58.2

Figure 58.3

Figure 58.4

Figure 58.5

Figure 58.6

Figure 58.7

Figure 58.8

Figure 58.9

Figure 58.10

Figure 60.1

Figure 60.2

Figure 60.3

Figure 60.4

Figure 60.5

Figure 60.6

Figure 60.7

Figure 60.8

Figure 61.1

Figure 61.2

Figure 62.1

Figure 62.2

Figure 62.3

Figure 62.4

Figure 62.5

Figure 63.1

Figure 63.2

Figure 63.3

Figure 64.1

Figure 64.2

Figure 64.3

Figure 65.1

Figure 65.2

Figure 66.1

Figure 66.2

Figure 67.1

Figure 67.2

Figure 67.3

Figure 68.1

Figure 68.2

Figure 70.1

Figure 70.2

Figure 71.1

Figure 71.2

Figure 72.1

Figure 72.2

Figure 72.3

Figure 72.4

Figure 73.1

Figure 73.2

Figure 73.3

Figure 74.1

Figure 74.2

Figure 74.3

Figure 74.4

Figure 75.1

Figure 75.2

Figure 75.3

Figure 75.4

Figure 75.5

Figure 75.6

Figure 76.1

Figure 76.2

Figure 76.3

Figure 77.1

Figure 77.2

Figure 77.3

Figure 78.1

Figure 78.2

Figure 79.1

Figure 79.2

Figure 79.3

Figure 80.1

Figure 80.2

Figure 80.3

Figure 81.1

Figure 81.2

Figure 81.3

Figure 81.4

Figure 81.5

Figure 82.1

Figure 82.2

Figure 82.3

Figure 83.1

Figure 83.2

Figure 83.3

Figure 83.4

Figure 83.5

Figure 83.6

Figure 83.7

Figure 83.8

Figure 84.1

Figure 84.2

Figure 84.3

Figure 84.4

Figure 84.5

Figure 84.6

Figure 84.7

Figure 84.8

Figure 84.9

Figure 84.10

Figure 84.11

Figure 84.12

Figure 85.1

Figure 86.1

Figure 86.2

Figure 87.1

Figure 88.1

Figure 88.2

Figure 88.3

Figure 88.4

Figure 88.5

Figure 89.1

Figure 89.2

Figure 89.3

Figure 90.1

Figure 90.2

Figure 90.3

Figure 91.1

Figure 91.2

Figure 92.1

Figure 92.2

Figure 92.3

Figure 92.4

Figure 92.5

Figure 92.6

Figure 92.7

Figure 92.8

Figure 92.9

Figure 92.10

Figure 93.1

Figure 93.2

Figure 93.3

Figure 95.1

Figure 96.1

Figure 98.1

Figure 98.2

Figure 98.3

Figure 98.4

Figure 98.5

Figure 99.1

Figure 99.2

Figure 99.3

Figure 100.1

Figure 100.2

Figure 100.3

Figure 100.4

Figure 100.5

Figure 101.1

Figure 101.2

Figure 101.3

Figure 102.1

Figure 102.2

Figure 103.1

Figure 104.1

Figure 104.2

Figure 104.3

Figure 104.4

Figure 105.1

Figure 105.2

Figure 105.3

Figure 106.1

Figure 107.1

Figure 107.2

Figure 107.3

Figure 107.4

Figure 108.1

Figure 108.2

Figure 109.1

Figure 109.2

Figure 109.3

Figure 109.4

Figure 109.5

Figure 110.1

Figure 110.2

Figure 110.3

Figure 111.1

Figure 111.2

Figure 111.3

Figure 112.1

Figure 113.1

Figure 113.2

Figure 113.3

Figure 114.1

Figure 114.2

Figure 114.3

Figure 114.4

Figure 114.5

Figure 114.6

Figure 114.7

Figure 115.1

Figure 115.2

Figure 115.3

Figure 116.1

Figure 117.1

Figure 117.2

Figure 117.3

Figure 117.4

Figure 118.1

Figure 118.2

Figure 118.3

Figure 119.1

Figure 119.2

Figure 120.1

Figure 120.2

Figure 121.1

Figure 121.2

Figure 122.1

Figure 122.2

Figure 124.1

Figure 124.2

Figure 124.3

Figure 125.1

Figure 126.1

Figure 127.1

Figure 127.2

Figure 127.3

Figure 127.4

Figure 127.5

Figure 127.6

Figure 127.7

Figure 127.8

Figure 127.9

Figure 127.10

Figure 127.11

Figure 127.12

Figure 127.13

Figure 127.14

Figure 127.15

Figure 129.1

Figure 129.2

Figure 130.1

Figure 130.2

Figure 130.3

Figure 130.4

Figure 130.5

Figure 130.6

Figure 131.1

Figure 131.2

Figure 132.1

Figure 132.2

Figure 132.3

Figure 133.1

Figure 133.2

Figure 133.3

Figure 133.4

Figure 133.5

Figure 133.6

Figure 133.7

Figure 133.8

Figure 133.9

Figure 134.1

Figure 134.2

Figure 134.3

Figure 135.1

Figure 135.2

Figure 135.3

Figure 135.4

Figure 135.5

Figure 136.1

Figure 137.1

Figure 137.2

Figure 138.1

Figure 139.1

Figure 139.2

Figure 140.1

Figure 140.2

Figure 140.3

Figure 140.4

Figure 140.5

Figure 141.1

Figure 141.2

Figure 141.3

Figure 141.4

Figure 141.5

Figure 141.6

Figure 141.7

Figure 141.8

Figure 141.9

Figure 142.1

Figure 142.2

Figure 142.3

Figure 142.4

Figure 142.5

Figure 142.6

Figure 144.1

Figure 145.1

Figure 146.1

Figure 146.2

Figure 147.1

Figure 147.2

Figure 148.1

Figure 149.1

Figure 150.1

Figure 153.1

Figure 153.2

Figure 155.1

Figure 155.2

Figure 155.3

Figure 155.4

Figure 155.5

Figure 156.1

Figure 156.2

Figure 156.3

Figure 156.4

Figure 156.5

Figure 157.1

Figure 157.2

Figure 157.3

Figure 158.1

Figure 158.2

Figure 159.1

Figure 160.1

Figure 160.2

Figure 160.3

Figure 160.4

Figure 160.5

Figure 160.6

Figure 160.7

Figure 161.1

Figure 161.2

List of Tables

Table 1.1

Table 2.1

Table 8.1

Table 8.2

Table 8.3

Table 9.1

Table 9.2

Table 14.1

Table 14.2

Table 16.1

Table 17.1

Table 19.1

Table 22.1

Table 23.1

Table 46.1

Table 47.1

Table 47.2

Table 52.1

Table 57.1

Table 58.1

Table 64.1

Table 64.2

Table 71.1

Table 80.1

Table 82.1

Table 88.1

Table 89.1

Table 90.1

Table 97.1

Table 112.1

Table 123.1

Table 123.2

Table 124.1

Table 125.1

Table 125.2

Table 125.3

Table 131.1

Table 132.1

Table 145.1

Table 146.1

Table 153.1

Table 153.2

Table 158.1

Table 158.2

Equine Reproductive Procedures

John J. Dascanio, VMD

Diplomate ACT and ABVP (Equine)

Professor

Ross University School of Veterinary Medicine

Department of Clinical Sciences

Basseterre, St Kitts, West Indies

Lincoln Memorial University – College of Veterinary Medicine

Harrogate, TN, USA

Patrick M. McCue, DVM, PhD

Diplomate ACT

Professor

Department of Clinical Sciences

College of Veterinary Medicine and Biomedical Sciences

Colorado State University

Fort Collins, CO, USA

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Library of Congress Cataloging-in-Publication Data

Dascanio, John J. (John Joseph), 1961– author.

Equine reproductive procedures / John J. Dascanio, Patrick M. McCue.

pages cm

Includes bibliographical references and index.

ISBN 978-0-470-96039-4 (pbk.)

1. Horses—Reproduction. 2. Horses—Breeding. I. McCue, Patrick M., author. II. Title.

[DNLM: 1. Horses—physiology. 2. Reproduction—physiology. 3. Breeding. 4. Reproductive Techniques, Assisted—veterinary. SF 768.2.H67]

SF768.2.H67D37 2014

636.1′082—dc23

2014005684

Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books.

Cover image: All photos provided by editor.

Cover design by Jennifer Miller Designs.

1 2014

List of Contributors

Fausto Bellezzo, DVM

Department of Clinical Sciences

College of Veterinary Medicine and Biomedical Sciences

Colorado State University

Fort Collins, CO, USA

Jillian Bishop, BS

Equine Reproduction Laboratory

Colorado State University

Fort Collins, CO, USA

Etta A. Bradecamp, DVM

Diplomate ACT and ABVP (Equine)

Rood and Riddle Equine Hospital

2150 Georgetown Road

Lexington, KY, USA

Leonardo Brito, DVM, PhD

Diplomate ACT

US Laboratory Manager

ABS Global, Inc.

1525 River Road

DeForest, WI, USA

Julie T. Cecere, DVM, MS

Diplomate ACT

Clinical Assistant Professor

Department of Large Animal Clinical Sciences

Virginia-Maryland Regional College of Veterinary Medicine

Blacksburg, VA, USA

John J. Dascanio, VMD

Diplomate ACT and ABVP (Equine)

Professor

Ross University School of Veterinary Medicine

Department of Clinical Sciences

Basseterre, St Kitts, West Indies

Current Address: Lincoln Memorial University – College of Veterinary Medicine

Harrogate, TN, USA

Ryan A. Ferris, DVM, MS

Diplomate ACT

Assistant Professor

Department of Clinical Sciences

College of Veterinary Medicine and Biomedical Sciences

Colorado State University

Fort Collins, CO, USA

Amanda I. Glazar, PhD

Director, Adult Learning and Outcomes

Global Education Group Ltd

2629 West Main Street

Littleton, CO, USA

Richard D. Holder, DVM

Hagyard Equine Medical Institute

4250 Iron Works Pike

Lexington, KY, USA

G. Reed Holyoak, DVM, PhD

Diplomate ACT

Department Head and Professor

Department of Veterinary Clinical Sciences

Okalahoma State University

Stillwater, OK, USA

Teri L. Lear, PhD

Associate Professor

Department of Veterinary Science

Gluck Equine Research Center

University of Kentucky

Lexington, KY, USA

Charles Love, DVM, PhD

Associate Professor

Large Animal Clinical Sciences

College of Veterinary Medicine

Texas A&M University

College Station, TX, USA

Patrick M. McCue, DVM, PhD

Diplomate ACT

Professor

Department of Clinical Sciences

College of Veterinary Medicine and Biomedical Sciences

Colorado State University

Fort Collins, CO, USA

Charles F. Scoggin, DVM, MS

Diplomate ACT

Resident Veterinarian

Claiborne Farm

Lexington, KY, USA

Sofie Sitters, DVM

Department of Equine Sciences

Faculty of Veterinary Medicine

Utrecht University

Utrecht, the Netherlands

D. N. Rao Veeramachaneni, PhD

Professor

Department of Biomedical Sciences

Colorado State University

Fort Collins, CO, USA

Karen Wolfsdorf, DVM

Diplomate ACT

Hagyard Equine Medical Institute

4250 Iron Works Pike

Lexington, KY, USA

Preface

The goal of this book, Equine Reproductive Procedures, is to provide equine professionals with practical clinical information on basic and advanced techniques in the field of equine reproduction. This book should be of assistance to veterinary students, graduate students, researchers, and equine practitioners.

The book contains chapters on reproductive management, diagnostic techniques, and therapeutic procedures on stallions, mares, and newborn foals. In our opinion, approximately 90% of reproductive procedures used in the horse industry are nearly identical throughout the world. However, it is the other 10% that is of major interest and may provide opportunities to expand one's clinical repertoire. Consequently, while the objective of this book is to provide examples of how reproductive procedures may be performed, it should not be construed that these are the only methods to achieve diagnostic or therapeutic goals.

We would like to thank our many mentors and colleagues for providing academic and clinical guidance over the years. We owe our professional careers to their collective wisdom. We would also like to thank our families for their unwavering support.

John J. Dascanio

Patrick M. McCue

Section I

Non-Pregnant Mare

Chapter 1

Reproductive Evaluation of the Mare

Patrick M. McCue

Department of Clinical Sciences, Colorado State University, USA

Introduction

The goals of a mare reproductive evaluation or breeding soundness examination (BSE) are to identify known or potential reproductive abnormalities and to evaluate the potential of a mare to become pregnant and carry a foal successfully to term. Mare reproductive examinations are performed in open (non-pregnant) mares prior to the onset of the breeding season, in problem mares during the breeding season, in barren mares at the end of the breeding season, as well as in mares with a history of embryonic loss, abortion, or other reproductive problems, or as part of a pre-purchase examination. The goal of this chapter is to provide an overview of the mare breeding soundness evaluation. Details on specific examinations will be covered in other chapters.

Equipment and Supplies

Obstetrical sleeve (non-sterile), obstetrical lubricant (non-sterile), tail wrap, metal bucket and garbage bag liner, non-irritant soap, roll cotton, vaginal speculum, obstetrical lubricant (sterile), obstetrical sleeve (sterile), uterine culture device, culture transport system (optional), uterine cytology device, glass slides, uterine biopsy forceps, formalin.

Examination Technique

Identification

All mares should be properly identified, and the breed, registration name, registration number, and date of birth recorded. Photographs should be taken or accurate drawings of markings and tattoos recorded.

Reproductive History

A complete breeding history should be obtained, including current reproductive status (maiden, barren, pregnant, or foaling), number of cycles bred during the last season, date of last breeding, breeding technique used (artificial insemination, natural cover, or pasture breeding), number of stallions, date of last foal, number of previous foals, and any previous history of abnormal estrous cycles, uterine infections, embryonic loss, or abortion.

Physical Examination

A general physical examination should be performed to assess whether the mare has the capacity to carry a foal to term. The evaluation should include, but is not limited to, examination of the oral cavity, eyes, and the respiratory, cardiac, and musculoskeletal systems. In addition, diet and body condition should be evaluated.

Perineal Conformation

The external genitalia (vulva) should be evaluated for conformation and muscular tone. The optimal perineal conformation consists of a vulva in a nearly vertical position with at least 70% of the vulva ventral to the brim of the pelvis. The muscular tone of the vulva should be sufficient to prevent or minimize aspiration of air into the vestibule or vagina. Horizontal sloping of the vulva secondary to recession of the anus or poor muscular tone to the labia of the vulva may predispose the mare to an ascending infection of the uterus.

Estrous Detection

The mare should be exposed to a stallion with good libido to evaluate estrous cycle stage. Adequate time should be taken to allow shy or nervous mares to express behavioral estrus. When teasing a mare with a foal, the foal must be restrained, and the mare may need to be restrained with a twitch before signs of estrus are exhibited.

Palpation Per Rectum

The entire reproductive tract, including the cervix, uterus, and ovaries, should be thoroughly and systematically examined by palpation per rectum. The tone of the uterus and cervix, size and consistency of ovarian follicles, and the presence of a recent ovulation or a corpus hemorrhagicum should be recorded. The presence of abnormal ovarian, parovarian (i.e., fimbrial cysts), or uterine structures should be recorded.

Ultrasonography Per Rectum

Manual palpation should be followed by a systematic ultrasound evaluation of the entire reproductive tract. Ultrasound is used in broodmares to visualize structures in the reproductive tract that cannot be palpated or differentiated on palpation per rectum, and in the early diagnosis of pregnancy, diagnosis of twins, and evaluation of potential ovarian or uterine pathology.

Vaginal Speculum Examination

A vaginal speculum examination is performed to evaluate the anatomy of the vagina and the external os of the cervix. Speculum examination is useful in determination of the stage of the estrous cycle (via cervical morphology and vaginal mucous membrane changes), and detection of urine pooling and the presence of cervical/vaginal inflammation or discharge.

Digital Examination of the Cervix

After the speculum examination is completed, the cervix should be examined manually for patency and the presence of abnormalities, such as adhesions, lacerations, or other cervical defects.

Uterine Culture

Culture of the uterine lumen is usually performed in conjunction with cytology for the diagnosis of endometritis. Endometritis can be suspected in mares that exhibit an abnormally short estrous cycle, vaginal or cervical discharge, inflamed cervix on speculum examination, and free fluid in the uterus during diestrus detected on ultrasound.

Endometrial Cytology

Cytologic evaluation of the uterus involves the collection and interpretation of cells lining the uterus (endometrium) and within the uterine lumen. Cytology is used in conjunction with culture and biopsy in the diagnosis of endometritis. Advantages of endometrial cytology for the diagnosis of endometritis include the ease of sample collection, low cost, and rapid availability of results.

Endometrial Biopsy

Endometrial biopsy involves collection of a small sample of the uterine lining (endometrium) for histologic evaluation. It is primarily used as an aid in the diagnosis of uterine disease and as a prognostic indicator of the ability of a mare to carry a foal to term. An endometrial biopsy can also be used as the sample source for culture and cytologic evaluation.

Other Tests

The standard examination procedures in the mare BSE may not identify the cause of subfertility. Consequently, other examinations may be indicated (Table 1.1).

Table 1.1 Diagnostic tests that may be performed in addition to the standard tests in a mare breeding soundness evaluation.

Additional Comments

Interpretation of the results of a mare BSE should take into account the mare's age, reproductive history, breed, stallion, breeding management, and other factors. Ultimately the goals are to determine the potential for fertility and detect abnormalities that may be associated with reduced fertility. Management and therapeutic options may be outlined to help optimize a successful outcome. It is important to emphasize that a mare BSE is only an evaluation of potential fertility and that the true assessment of fertility is the ability of the mare to conceive and carry a foal to term.

Further Reading

LeBlanc MM, Lopate C, Knottenbelt D, Pascoe R. 2003. The Mare. Equine Stud Farm Medicine and Surgery. London: Elsevier, pp. 113–213.

McCue PM. 2008. The problem mare: management philosophy, diagnostic procedures, and therapeutic options. J Eq Vet Sci28: 619–26.

Chapter 2

Teasing

Patrick M. McCue

Department of Clinical Sciences, Colorado State University, USA

Introduction

The 21-day equine estrous cycle can be divided into two phases: estrus and diestrus, based on sexual receptivity to a stallion. Estrus is the period during which a mare is sexually receptive to the advances of a stallion. Behavioral estrus is stimulated by increasing levels of estradiol produced by the developing dominant follicle in the absence of progesterone. The average length of estrus has been reported to be 6.5 days, with a range of 4.5–8.9 days. Ovulation typically occurs 24–48 hours before the end of estrus. An increase in progesterone from the developing corpus luteum is responsible for the cessation of behavioral estrus. Behavioral diestrus largely overlaps the physiological luteal phase associated with high levels of progesterone produced by the corpus luteum.

Equipment and Supplies

Stallion, lead shank, helmet.

Technique

A mare should be teased with a stallion that exhibits good libido in order to successfully evaluate estrous cycle stage.

Adequate time should be taken to allow shy or nervous mares to express behavioral estrus.

Knowledge of the mare's previous behavioral patterns may be helpful.

In addition, observation of the mare's behavior with other horses in a pasture or paddock may indicate when a mare is in estrus.

Individual Teasing

An individual mare should be exposed to a stallion for an interval of time that is long enough for her to show estrous or diestrous types of behavior. It is preferable to have both the mare and stallion restrained for individual teasing; however, if only one handler is present, it is better to have the stallion restrained with the mare loose so that abnormal behaviors in the stallion may be corrected. Mares that remain indifferent may need to be teased longer, teased with a different stallion, or may just show more subtle signs. Mares may be reluctant initially and yet later show frank estrous behavior (i.e., break down). Sometimes full behavioral estrus is only expressed within a few hours of ovulation. It is also not unusual for a mare to fail to show signs of estrus while being directly teased to a stallion, and then break down as the stallion leaves. Mares may also display estrus at the mere sound or sight of a stallion. Mares with a foal by their side may be reluctant to display estrous behavior readily as they are concerned for their foal's safety.

Group Teasing

A stallion may be used to tease more than one mare concurrently if he is brought to the edge of a pen or turned out adjacent to a group of mares. Mares are allowed to approach the stallion at will in such a teasing program. However, some mares will not approach the stallion and will not express estrus when teased as part of a group. It may be necessary to tease such mares individually.

It is often not very efficient to tease mares as a group, since often the only mares that come to the fence or tease rail are assertive mares in heat or mares that want to attack the stallion. One may not be able to determine the heat status of mares that remain a distance from the stallion. It is generally more effective, but certainly more time consuming, to tease mares individually. Mares that are less dominant mares or further away from the fence or tease rail should still be observed for estrous behavior.

Behavioral Responses

Common behavioral responses of mares in estrus and diestrus are listed in Boxes 2.1 and 2.2 and shown in Figures 2.1 and 2.2.

c02f001

Figure 2.1 Mare in estrus (i.e., teasing in heat). Note the base-wide stance, raised tail, and urination.

c02f002

Figure 2.2 Mare in diestrus (i.e., out of heat). Note the ears and aggressive stance.

Box 2.1 Common Behavioral Characteristics of Mares in Estrus

Tail raised and arched or deviated to one side

Rhythmic eversion of the labia and exposure of clitoris (winking)

Passive urination

Ears relaxed and either held forward or in a neutral position

Rear limbs slightly abducted (i.e., wide-based stance)

Stifles and hocks flexed

Lowering of the pelvis (i.e., squatting)

Leaning into fence or gate

Vocalization (squealing)

Calm behavior; does not try to bite or strike stallion

Box 2.2 Common Behavioral Characteristics of Mares in Diestrus

Tail held down or aggressively switched from side to side

Ears pinned back

Aggressive toward advances of the stallion

Biting at the stallion

Attempt to move away from the stallion

Squealing or vocalization

Calm behavior; does not try to bite or strike stallion

It should be noted that expression of estrus does not always indicate that a mare is in the follicular phase of the estrous cycle. Seasonally anovulatory mares, ovariectomized mares, and pregnant mares have all been reported to occasionally show signs of estrus when teased with a stallion. This may be due to submissive behavior or a lack of progesterone.

Records

Maintaining an accurate record of teasing behavior will be helpful when monitoring the estrous cycle of a mare. Notations can be made as to whether or not the mare exhibits overt, subtle, or no signs of estrus throughout a cycle (Table 2.1).

Table 2.1 Abbreviations for responses of a mare to a stallion (i.e., teasing behavior).

Silent Estrus

Maiden mares may not show heat well and foaling mares may not show heat at all unless the foal is restrained and/or safely away from the stallion. Subordinate mares may be inhibited from expressing estrus in the presence of a dominant mare. In addition, a mare may have a preference for, or an aversion toward, an individual stallion. Mares with silent estrus may have lower concentrations of estradiol 17β than mares expressing normal estrus.

Additional Comments

There are many systems used for teasing mares, including chutes, rails, fences, pens, and paddocks. Keys to successful teasing are patience, persistence, and knowing the behavioral characteristics of each mare. Consequently, it is advantageous for the same individual(s) to tease mares each day, so that slight variations in individual responses can be recognized.

Further Reading

Ginther OJ. 1979. Reproductive Biology of the Mare: Basic and Applied Aspects. Ann Arbor, MI: McNaughton and Bunn, pp. 59–68.

McCue PM, Scoggin CF, Lindholm ARG. 2011. Estrus. In: McKinnon AO, Squires EL, Vaala WE, Varner DD (eds). Equine Reproduction, 2nd edn. Ames, IA: Wiley Blackwell, pp. 1716–27.

Chapter 3

Tail Wrap and Preparation/Washing of the Perineum

John J. Dascanio

Lincoln Memorial University—College of Veterinary Medicine, USA

Introduction

The perineum should be washed prior to any internal reproductive procedure in the mare and in preparation for foaling to remove gross debris and to reduce bacterial numbers. In addition, the perineum is washed prior to perineal surgery such as the placement of a Caslick suture (vulvoplasty). The perineum is also washed as part of the minimum contamination breeding technique to reduce contamination of the uterus during natural cover or artificial insemination.

Equipment and Supplies

Tail wrap, tail rope, non-irritant soap, roll cotton, stainless steel bucket, plastic bag/bucket liner, paper towels, examination gloves.

Placement of a Tail Wrap

A tail wrap should be placed prior to washing of the perineum. This may be a reusable neoprene wrap, Velcro wrap, gauze wrap, flexible elastic wrap (Vetrap™), or an obstetric sleeve.

Gauze is placed on the tail for a wrap using one of two techniques. With both techniques the wrap goes from the base of the tail to a level just below the ventral commissure of the vulva. Technique one is to start at the top of the tail and with every circumferential wrap, flip some tail hairs upward so that they become trapped between successive layers (Figure 3.1). This prevents the tail wrap from slipping down the tail. This tail wrap must be unwound to remove. The second type of gauze wrap starts at about the level of the ventral vulvar commissure (Figure 3.2). A small piece of gauze is left hanging and the wrap placed around the tail, moving upward to the tail base. Hair should not be included between layers, with each layer overlapping the previous slightly. Once at the tail base, the gauze is twisted 360 degrees so that the twisted part is on the dorsal tail, while the ventral aspect of the wrap remains flat and untwisted. This allows the twist to bite into the tail hair on the dorsum, preventing slippage of the wrap, while the flat underneath aspect prevents blood occlusion. The wrap is continued downward and is twisted upon every circumferential wrap ending at the point where the wrap began. The small hanging piece of gauze from the beginning is tied to the remaining wrap to prevent the wrap from coming loose. This wrap may be pulled from the top to slide down the tail and removed without having to unwind the wrap when the procedure is completed.

If an obstetrical sleeve is used for a tail wrap, the tail is placed entirely inside the sleeve. The sleeve may be split at the tail base and tied together to close the sleeve around the tail base, or elastic adhesive tape or an elastic band and clamp may be used to wrap around the sleeve at the tail base to secure it. This type of tail wrap is useful for mares with diarrhea to prevent spoilage of the tail hairs.

If a flexible elastic wrap is used such as Vetrap™, the wrap may either be used to wrap the entire tail or the upper portion (Figure 3.3). The entire tail is wrapped for a dystocia or a fetotomy to prevent tail hairs from interfering with the procedure. To place the entire tail in a wrap, fold the tail hairs so that the hairs do not extend beyond the tail stump. Wrap the elastic wrap around the tail/tail hairs so that no hair is visible along the entire tail length. This in effect creates a club with the tail wrapped completely.

After wrapping, the tail is held to the side so that the perineum can be washed or the tail is tied to the mare (Figure 3.4).

Alternative tail wrap techniques include use of a sock held in place by 2 inch medical tape (Figure 3.5) or a plastic bag (75 × 25 cm) held in place by 2.5 cm rubber tubing and a clamp (Figure 3.6). The wrapped tail can be held out of the way by using an elastic cord (Figure 3.7) or being tied to the mare as previously described. A neoprene Velcro lower leg wrap may also be used as a reusable tail wrap, but must be disinfected properly between mares.

c03f001

Figure 3.1 Gauze tail wrap with tail hairs flipped up to prevent sliding of the wrap down the tail.

c03f002

Figure 3.2 Gauze tail wrap twisted 360 degrees on the dorsum of the tail while the ventral aspect is wide.

c03f003

Figure 3.3 Elastic tail wrap encompassing the entire tail.

c03f004

Figure 3.4 Tail wrap tied to the mare with quick release knots.

c03f005

Figure 3.5 Tail wrap using a sock and secured with medical tape.

c03f006

Figure 3.6 Tail wrap using a plastic bag and secured with rubber tubing and a clamp. An extra clamp is shown above the tail.

c03f007

Figure 3.7 Wrapped tail held out of the way using an elastic cord.

Washing Perineum Technique

Feces should be evacuated from the rectum prior to washing the perineum.

The perineum is usually washed using one of two techniques: a bucket technique or a water hose technique.

The bucket technique requires a clean bucket with a disposable liner. A small clean garbage bag works as a liner (Figure 3.8). The liner can be filled with warm water and the top tied to prevent spillage when carrying or to prevent dirt and dust from blowing into the water in a barn environment (Figure 3.9). When ready to use, simply open the plastic bag over the bucket. This also provides some biosecurity, with a new disposable liner used between horses or farms. The classic clean hand, dirty hand technique is used to wash the mare. Handfuls of loose cotton are placed into the bucket of water. The person washing the mare wears disposable examination gloves. The clean hand retrieves a piece of cotton and holds it away from the bucket over the dirty hand and allows the water to drip over the dirty hand. The dirty hand is massaged under the water flow to clean it of any dirt or debris. The cotton piece is then dropped from the clean hand into the dirty hand. The dirty hand is then used to

wash the mare's perineum using concentric circles going outward from the vulva. A mild detergent may be used to help remove smegma and organic debris. The perineum is successively washed until the cotton washing the vulva appears clean after performing the wash. Typically three to four wash/rinse cycles are needed for the average mare. It is important to insure that all soap is rinsed from the perineum.

The water hose technique is less labor intensive and involves fewer materials than the bucket technique and works well where there are stationary horse stocks. A gentle stream of water or a shower-type water nozzle should be used. Disposable examination gloves are placed on the hands and the perineum is rinsed with water to remove any gross debris. A mild detergent soap is placed directly on the labia or is placed on the back of the hand. The back of the hand and knuckles are used to vigorously scrub the perineum, using concentric circles going outward from the vulva (Figure 3.10). The gloved hand used to wash the mare is rinsed with the water hose. When rinsing the perineum with the water hose, the back of the hand/fingers may be used to help remove soap residue (Figure 3.11). The perineum is scrubbed until clean, usually involving three to four wash/rinse cycles.

Once the mare has been cleaned adequately, a final wetted cotton piece is squeezed to remove most of the water and the lips of the vulva are separated. The cotton piece is then swiped from the dorsal to the ventral commissure just inside the mucosa to remove any debris that wicked in between the labia. This is done usually only once so as to avoid trauma to the mucosa. The perineum is dried with a clean paper towel in the same outward concentric pattern used to wash the mare.

c03f008

Figure 3.8 Bucket with liner to provide clean water for washing mares. All materials are disposed of between horses.

c03f009

Figure 3.9 Bucket with liner closed to prevent dirt from contaminating water or to prevent water spillage when walking quickly with the bucket.

c03f010

Figure 3.10 Washing the perineum with a gloved hand.

c03f011

Figure 3.11 Rinsing the perineum with a gloved hand and a gentle shower spray. Note Velcro/neoprene tail wrap.

Interpretation

When washing the mare, care should be taken so that water running down the back legs does not cause the mare to kick outward.

A disinfectant soap should not be routinely used in order to prevent killing normal skin flora and to prevent overgrowth of a pathogenic bacteria. A disinfectant soap may be used for surgical procedures.

The perineum should be scrubbed from the labia to 15–30 cm outward from the labia so that if the mare moves when entering the vulva with a gloved arm, the gloved arm will remain clean.

Chapter 4

Placement of a Tail Rope

John J. Dascanio

Lincoln Memorial University—College of Veterinary Medicine, USA

Introduction

The mare's tail is often tied to the side to keep it from interfering with access to the rectum or reproductive tract. Horse tail hairs can be very abrasive to mucosal tissue or could lead to bacterial contamination from dirt/fecal contamination. In most cases the mare's tail should be tied to her body so that if she were to fall down or jump out of stocks, the tail would not be injured. If the tail is tied to a rigid structure, such as the stocks, it should be tied with an elastic cord that is attached to a lightweight piece of twine that would break when significant tension is placed on it.

Equipment and Supplies

Tail rope equal to 2× the length of the mare, bungee cord, tail wrap, twine.

Technique for Tying a Tail Rope

Being careful to not stand behind the mare, the tail is grasped and the tail dock (or end) is located.

The running end of the rope (short end) is laid across the tail hairs just caudal to the tail dock (Figure 4.1).

The tail hairs are flipped upward and over the rope (Figure 4.2).

The running end of the rope is passed under the tail and over the flipped tail hairs (Figure 4.3).

A bight (loop) from the running end of the rope is tucked under the rope encompassing the tail and the standing part of the rope (longer end) is pulled to tighten the tail rope (Figures 4.4 and 4.5).

The standing part of the rope is then passed over the mare's back so that if the tail is moved to the

left side of the mare's body, the rope is passed over her back to her right shoulder. The rope is then passed between her front legs. It is then passed over her back and tied with a quick release knot at her back (Figure 4.6).

This method works well when having to breed one mare, especially if there are no stocks around.

Care should be exercised as some mares may find the rope around their chest constricting and may need time to acclimatize to it.

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Figure 4.1 Running end of the rope (short end) is laid across the tail hairs just caudal to the tail dock.

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Figure 4.2 Tail hairs are flipped upward and over the rope.

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Figure 4.3 Running end of the rope is passed under the tail and over the flipped tail hairs.

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Figure 4.4 A bight (loop) from the running end of the rope is tucked under the rope encompassing the tail.

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Figure 4.5 Standing part of the rope (longer end) is pulled to tighten the tail rope.

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Figure 4.6 Standing part of the rope is passed over the mare's back to her right shoulder. The rope is then passed between her front legs. It is then passed over her back and tied with a quick release knot at her back.

Technique for Using an Elastic Cord to Tie the Mare's Tail to the Stocks

The mare's wrapped tail is encompassed by a stretchy cord such as a bungee cord with both ends of the bungee remaining free (Figure 4.7).

The bungee cord is hooked to a loop of twine attached to the stocks (Figure 4.8). The twine will break if too much tension is placed on it (due for example to the mare jumping out of the stocks). The bungee cord should never be directly attached to the stocks.

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Figure 4.7 Mare's wrapped tail is encompassed by a stretchy cord such as a bungee cord with both ends of the bungee remaining free.

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Figure 4.8 Bungee cord is hooked to a loop of twine attached to the stocks.

The bungee cord is a much quicker method of holding the tail out of the way, especially if a Velcro reusable tail wrap is used. This method works well when multiple mares are checked for cyclicity.

Further Reading

Leahy JR, Barrow P. 1953. Restraint of Animals, 2nd edn. Ithaca, NY: Cornell Campus Store.

Chapter 5

Perineal Conformation Evaluation

John J. Dascanio

Lincoln Memorial University—College of Veterinary Medicine, USA

Introduction

Perineal conformation evaluation is an integral part of the mare breeding soundness examination and should be performed in any mare presented for reproductive evaluation. While there could be defects present in the perineal area, such as from trauma, most commonly evaluation is directed to the vulva. The vulva serves as the first barrier to contamination of the reproductive tract. Defects in perineal conformation may predispose the reproductive tract to inflammation and infection.

Defects in perineal conformation are most often remedied by performing vulvoplasty (Caslick operation). Alternative surgical perineal procedures include the Pouret operation, Slusher vestibuloplasty, or Gadd technique.

Equipment and Supplies

Tail wrap, exam gloves, flashlight.

Technique

Wearing examination gloves, hold the tail to the side so as to visualize the anus, perineum, and vulva.

Visualize the declination of the vulvar lips from vertical (Figure 5.1).

Note any disruption to the labia such as from previous trauma or surgeries.

Note any discharges from the vulva or on the skin ventral to the vulva. Purulent discharges may accumulate as a crusty discharge on the skin of the vulva and ventral perineum (Figure 5.2). Since the tail is usually relaxed and lying against the vulva, discharges often accumulate on the ventral aspect of the tail in the tail hairs. This area should be examined prior to placement of a tail wrap as a clue that there is a passive vaginal discharge.

Normal urine crystal/mucus accumulation on the ventral labia may appear as a chalky white discharge, especially evident when mares are in heat (Figure 5.3). There should be no discharge on the ventral skin or in the tail hairs since this is a normal discharge.

Wearing exam gloves push the index fingers on either side of the labia to determine the relationship of the vulvar opening to the ventral pelvis.

Place the thumbs on either side of the labia and pull the labia apart, exposing the vestibule to perform the Windsucker test (Figure 5.4).

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Figure 5.1 Normal conformation with two thirds of the vulvar opening lying below the level of the pelvic brim.

(Used with permission from: Equine Reproduction, McKinnon, Squires, Vaala, Varner 2013.)

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Figure 5.2 Mare with a purulent vaginal discharge and dried discharge on the inner aspect of the hind