1. The Reproductive System

2. Canine Testis (104X) 1. Seminiferous tubules (showing spermatogenesis) 2. Interstitial tissue (with Leydig cells, which produce androgens

3. Positions of the Scrotum: A. Perineal (tomcat) B. Intermediate (dog) C. Inguinal (bull) 1.Testicular artery 2.Deferent duct (ductus deferens) 3.Testis 4.Pelvic symphysis

4. Equine Testis 1. Head of epididymis 2. body of epididymis 3. Pampiniform plexus

5. Equine testis 1. Testis 2. Epididymis 4. Deferent duct (ductus deferens) 5. Pampiniform plexus

6. Longitudinal section of testis and epididymis 1.Tunica albuginea 2.Mediastinum 3.Seminiferous tubules 4.Straight tubules 5.Rete testis 7. Deferent duct (ductus deferens) 8. Head of epididymis 9. Body of epididymis 10. Tail of epididymis

7. Canine testicle (corrosion cast) Testicular artery (red); Pampiniform plexus (blue) Deferent duct (yellow)

8. Scrotum of a bull Cremaster muscle contracted Stress or cold temperature

9. Bladder and Urethra (Equine), opened 6. Opening of ejaculatory duct 7. Openings of prostatic ducts 8. Openings of bulbourethral ducts 9. Vesicular gland 10 Prostate 11. Bulbourethral gland

10. Accessory Reproductive Glands A.Stallion B.Bull C.Boar D.Dog 4. Ampullary Gland 5 Vesicular Gland 6. Body of prostate 7. Bulbourethral gland

11. Male Urogenital Apparatus (dog) 2. Deferent duct 3. Urethra 5. Os penis 6’ bulb of penis 7. bulbis glandis (glans) 8. Prepuce 9. Prostate

12. Quiescent and erect penis (canine)

13. Urogenital organs of the tomcat 5. Testicle 6. Penis 7. Bulbourethral gland 8. Prostate 9. Deferent duct

14. Feline Penis 1.Prostate 3 Urethra 4. Bulbourethral gland 2.7. Testis 8. Prepuce 9. Glans (with spines)

15. Feline Glans Penis (Scanning Electron Micrograph)

16. Feline Penis (caudal view) 1. Tail (raised) 7. Penis 8. Retractor penis muscle 9. bulbourethral gland

17. Tomcat spraying (urine)

18. Feline Mating Posture

19. Equine Penis (out of sheath)

20. Bovine Penis

21. Bovine Penis and Surrounding structures

22. Reproductive organs of the Rooster 1. Testis; 2. Kidney; 3. Deferent duct; 4. Cloaca

23. Female Reproductive Tract 4. Ovary; 5 Fallopian Tube; 6 Uterus; 7. Cervix; 8. Vagina 12. Vulva

24. The bovine ovary 1. Ovarian Follicle (egg ready to be ovulated)

25. The ovary of a bitch (quiescent)

26. Canine ovary with multiple follicles Canines reproduce in litters, so multiple follicles mature at one time.

27. Ovary of the sow Do sows have singles or litters?

28. Diagram of stages of ovarian activity 1. Ovarian medulla; 5. Primordial follicle; 6. Primary follicle; 7. Secondary follicle; 8. early tertiary follicle; 9. mature follicle; 10. Oocyte; 11. Ruptured follicle; 13. Corpus luteum

29. Cow Reproductive tract 1.Ovary; 2. Infundibulum; 3. Uterine tube (Fallopian tube); 4. Horn of uterus; 6. Body of uterus; 8. Cervix; 10. Vagina; 12. External urethral opening; 14. Clitoris; 15. Vulva

30. The Reproductive Tract of the Bitch Vagina has been opened. 1. Ovaries 2. Uterine horns 3. Uterine body 4 Vagina

31. The reproductive tract of the mare 1. Right ovary 2. Uterine (Fallopian) tube 3. Horn of uterus 4. Body of uterus 5. Cervix 6. Vagina

32. Reproductive Tract of the Cow Vagina has been opened Note differing shapes of the uteri.

33. The Reproductive Tract of the Sow 1. Left ovary 4. Uterine (Fallopian) Tube 5. Uterine Horn (6. Broad Ligament) 7. Parallel segments of the uterine horns 8. Body of Uterus 9. Cervix 10. External uterine orifice 13. Vagina 16. Vestibule

34. Reproductive Tract of the Hen 1. Ovary with follicles in different stages of development 2. Oviduct 3. Uterus 4. Colon 5. Cloaca

35. Ventral view of reproductive organs in the hen 1. Ovary with follicles in different stages of development; 2. Oviduct; 3. Uterus; 4. Colon; 5. Cloaca

36. Variation in Uterine Shape by Species A. Uterus duplex (rabbit); B. Uterus bicornis (small body—sow and cow); C. Uterus bicornis (large— mare); D. Uterus Simplex (woman).

37. The Estrus Cycle Canine Estrous Cycle Graphs contributed by Bruce E Eilts on 12-July-01 modified by Eric Huey Proestrus, estrus (during which ovulation occurs), diestrus, metestrus (quiet phase between cycles) Compare & Save

38. Some Specific Reproductive Parameters (Table 5-1, page 206) SpeciesPubertyCycle Estrus DurationOvulationPregnancy Dog6-9 mo>90d9 days3 days after62 days Cat6-9 movaries7-10 days24 hrs after63-65 Horse20 mo19-22d5-6 days1-2 d before end330d/11mo Cattle6-18 mo18-24d18 hours10-12 hrs bef end280d/9 mo Sheep6-12 mo16-18d24-36 hours30-36 hrs after150d/5mo Goat4-8 mo21d24-36 hours30-36 hrs after150d/5mo Pig5-10 mo19-21d48-72 hours35-45 hrs after114d (!4 mo)

39. Pregnancy Compare & Save

40. Formation of Extraembryonic Membranes 1. Embryo 2. Chorion 4. Yolk sac 5. Allantois 6. Amnion 7. Chorioallantois

41. Zonary Placenta (carnivores) The zonary placenta has the closest and most interaction between the fetal membranes and the endometrium. Compare & Save

42. Equine Placentation The equine placenta is not very complex. The villi do not penetrate deeply into the endometrium.

43. Equine Placentation Endometrial cups (mare) during early pregnancy. These cups are responsible for the production of pregnant mare's serum gonadotropin (PMSG). Compare & Save

44. Porcine Placentation Like the horse, this a relatively simple placenta

45. Ruminant Placentation (bovine) Ruminants have a cotyledonary placenta with many placentomes Compare & Save

46. Partial separation of the maternal and fetal placentome This placentome is partially separated, showing the interdigitation of the maternal and fetal parts

47. Equine fetus 1. Yolk sac; 2. Chorionic girdle; 3. Allantochorion

48. Discoidal placenta of a rat.

49. The outside of the cow placenta showing cotyledons

50. Separating the fetal membranes from the placenta

51. Peeling the placental cotyledon away from the fetal membrane. Note how interlaced the capillaries are; this is where nutrient exchange can take place.

52. Parturition

53. Note Stage 1 (restlessness, rolling), Stage 2 (active contractions, expulsion of the fetus) and Stage 3 (expulsion of fetal membranes, not shown)

54. Newborn foal with dam Developmental status shortly after birth. A, Neonatal foal with mother (the mare has yet to discharge the fetal membranes [after birth]). Compare & Save Compare & Save

55. Neonatal Guinea Pigs Developmental status shortly after birth. B, Newborn guinea pigs, which are born in a more developed state. Compare & Save

56. Neonatal Kittens with Queen Developmental status shortly after birth in altricial species. A, Newborn kittens. Compare & Save

57. Tree-Day-Old Mouse Pups Developmental status shortly after birth in altricial species. B, Three-day-old mouse pups. Compare & Save

58. Skeletal Ossification (canine) Progress of skeletal ossification in puppy. C, 1, 14, and 28 days after birth, respectively. Compare & Save Compare & Save

59. Lactation Provides colostrum and nutrition Compare & Save

60. Mammary Gland Distribution Distribution of mammary glands in certain mammals. The dots indicate the number of orifices on the teat. A, Sow. B, Bitch. C, Cat. D, Woman. E, Cow. F, Ewe and she-goat. G, Mare.

61. Holstein Udder Holstein cow with well-developed udder. 1, Mammary vein.

62. The Bovine Udder Transverse section of the abdominal floor and cranial quarters of the bovine udder. 1, External abdominal oblique; 2, internal abdominal oblique; 3, rectus abdominis; 4, peritoneum; 5, linea alba; 6, lymph vessel; 7, external pudendal vein; 8, external pudendal (mammary) artery; 9, medial laminae of suspensory apparatus; 10, lactiferous sinus; 11, papillary duct; 12, lateral laminae of suspensory apparatus.

63. Mammary Tissue Section of (A) nonlactating and (B) lactating mammary glands; a compound tubuloalveolar gland (70×). 1, Alveolus; 2, interlobular septum.