Broodmare Reproduction for the Equine Practitioner

Contents Section 1 Equine Reproductive Efficiency General Principles 3 Some Helpful Hints 3 Definitions 4 Rates, Terms, and Efficiency 6 Factors Influencing Pregnancy Rate 9 Causes of Early Embryonic Death (EED) 10 Section 2 Breeding Management Systems Terms and Terminology 16 Estrous Detection and Teasing Program 17 Behavior 20 Pasture Mating 21 Hand Mating 21 Artificial Insemination 23 Section 3 Preventive Medicine Program for Broodmares Biosecurity 28 Immunizations 31 Equine Influenza 38 Equine Herpesvirus 38 Equine Encephalitides 40 Equine Arteritis Virus 41 Rabies 42 Rotavirus 42 Equine Strangles 43 Anthrax 43 Potomac Horse Fever, Equine Monocytic Ehrlichiosis 44 Equine Protozoal Myelitis/Myeloencephalitis 45 Tetanus Toxoid 45 Botulism 46 Parasite Control 47 Nutrition 49 Section 4 Anatomy and Physiology Perineal Conformation and Anatomy 56 Vulva, Vestibule, and Vagina 57 Uterus, Uterine Tubes, Ovaries and Adnexa 60 Cervix 60 Uterus 61 Oviducts 64 Ovaries 66 Adnexa 67 Physiology of Ova Production and Fertilization 68 Folliculogenesis 68 Oogenesis 70 Fertilization 72 Section 5 Seasonality, the Estrous Cycle and its Manipulation and Artificial Control Seasonality 76 The Estrous Cycle 79 Points of Control 80 Progestogens 80 Prostaglandins 82 Gonadotropins 83 Options for Management 84 Estrous Synchronization Programs 84 Artificial Lighting 89 Estrus Suppression in Show and Performance Mares 90 Section 6 Breeding Serviceability Exam of the Mare History and Signalment 94 Physical Examination 95 External Perineum 96 Vaginal Examination 98 Rectal Exam and Ultrasonography 100 Endometrial Cytology 106 Endometrial Culture 110 Endometrial Biopsy 111 Hysteroscopy 114 Other Diagnostics 116 Section 7 Breeding Management Estrous Detection 118 Examinations 118 Records 120 Breeding by Live Cover 123 Breeding by Artificial Insemination 125 Fresh Semen on the Farm 125 Transported Extended Cooled Semen 127 Frozen Semen 128 Low-dose Hysteroscopic Insemination 129 Ovulation Management 130 hCG 130 Deslorelin 130 ProstaglandinF2-alpha 131 Post-Breeding Examination and Treatments 131 Section 8 Pregnancy Diagnosis Behavioral Signs of Pregnancy 134 Vaginoscopy 134 Rectal Examination for Signs of Pregnancy 135 Transrectal Ultrasonography 138 Hormonal Evaluations 141 Progesterone 141 Equine Chorionic Gonadotropin (eCG, PMSG) 142 Estogens 143 Tandem Hormons Assy 143 Relaxin 143 Management of Twin Conception 144 Early Intervention 145 Late Intervention 148 Fetal Sexing 149 Transabdominal Ultrasonography 150 Section 9 Early Embryonic Loss Early Pregnancy Considerations 154 Age Related Considerations 155 Uterine Tube Considerations 157 Uterine Environment Considerations 158 Section 10 Infectious Causes of Endometritis and Treatment Options Endometritis 162 Endometrosis 163 Anatomic Barriers of Defense 164 Physical Clearance Mechanism 166 Infectious Causes of Endometritis 167 Uterine Lavage 168 Uterine Ecbolics 170 Antimicrobial Therapy 170 Disinfectant Therapy 175 Alternative Therapies 176 Plasma 176 Colostrum 176 Mannose 176 Immunostimulants 177 Endometrial Curettage 177 Section 11 Non-infectious Causes of Infertility Cytogenetic Causes of Infertility 180 Definitions 180 Etiology 180 Three Groups of Individuals 181 Intersexuality 181 Gonadal Dysgenesis 184 Hybrids 185 Ovarian Tumors and Conditions 185 Granulosa Thecal Cell Tumors 185 Hematoma 185 Cystadenoma 187 Teratomas 187 Lymphosarcoma 188 Dysgerminoma 188 Arrhenoblastoma 188 Cystic Ovaries 188 Paraovarian Cyst 189 Other Causes of Non-Infectious Infertility 190 Twinning 190 Early Embryonic Death 190 Oviduct/Salpingitis 190 Uterine Cysts 191 Uterine Tumors 193 Abnormalities of the Cervix 194 Autoantibodies to the Zona Pellucida 194 Sperm Agglutinins 195 Hypothyroidism 195 Equine Cushing's Disease 195 Nutrition and Body Condition 196 Breeding Mismanagement 196 Transitional Season 197 Prolonged Lifespan of CL 197 Environmental Stress 197 Pregnancy 198 Section 12 Assisted Reproductive Technologies Components of ART 200 The Realities of ART 201 Why ART in Horses? 201 Limits Imposed 201 Artificial Insemination / Intrauterine Insemination 202 Embryo Transfer 203 Embryo Flushing Procedure 206 Embryo Shipment 209 Embryo Cryopreservation 209 Indications 210 Usual Procedure 210 Gamete Intrafallopian Transfer 211 Intracytoplasmic Sperm Injection 213 Intrafollicular Insemination 216 In Vitro Fertilization 216 Oocyte Retrieval / Ovum Pick-up / Follicular Aspiration 218 Oocyte Transfer or Intrafollicular Transfer of Oocytes 219 Oocyte Cryopreservation 219 Xenogeneic Gamete Intrafallopian Transfer 221 Zygote Intrafallopian Transfer 221 Glossary of Reproductive Terms 223 Index 235