vet-tech-therio-ch-11

  1. Normal anatomy of the queen
    • two ovaries
    • uterine tubes
    • uterus
    • cervix
    • vagina
    • mammary glands
  2. Ovaries
    dorsal (back) abdomen caudal to the kidneys
  3. Uterine tubes
    • fallopian tubes/oviducts
    • transport channel for ova between the ovaries and the uterus
  4. Uterus
    • Y-shaped
    • 2 uterine horns, uterine body
  5. Cervix
    thick-walled neck of the uterus connecting it to the vagina
  6. Vagina
    • extends caudally from the cervix
    • ends in the outermost portion fo the reproductive tract, the vulva (not as obvious in cat, even in heat)
  7. Mammary glands
    • 4 pairs
    • - 2 bilaterally symmetrical rows (ventral thoracic to ventral abdominal)
    • - right and left axillary (armpit), thoracic, abdominal and inguinal
    • - right and left mammary glands 1, 2, 3, and 4 (axillary to inguinal)
  8. Female cat is seasonably polyestrous
    • having estrous cycles during only part of the year
    • stimulated by increase in daylight
    • 16 hours daylight, will cycle throughout the year
    • can become pregnant again soon after parturition
  9. Spontaneous ovulation
    triggered by visual or pheromone
  10. Induced ovulator
    • ovulation is triggered by the act of mating
    • - once egg is released it is ready to be fertilized
    • - needs to be stimulated to release egg
    • in the absence of mating, the mature follicle regresses without ovulating
    • * different from the bitch
  11. Puberty
    • 4-18 months; usually 6-9 months
    • spay recommended 5-6 months
    • variation depends on:
    • - body weight - 2.3-2.5 kg (approx 5-6 lbs) in weight
    • - time of year - increasing daylight (winter may delay)
    • - breed - genetics
    • - nutrition - starvation will slow
    • long reproductive life
    • - often exceeds 14 or more years
    • - litter size may be reduced as queen ages - less eggs are ovulated
  12. Feline Estrous cycle
    • pro-estrus
    • estrus (behavioral estrus)
    • interestrus
    • anestrus
    • can/will spay cat in heat
  13. Pro-estrus
    • difficult to detect
    • first few days of heat, queen is calling but will not accept male's advances
    • ovarian follicles are beginning to grow, estrogen levels still low
  14. Estrus (behavioral estrus)
    • period (3-7 days) when the female will accept the male (tom)
    • follicles are mature, maximum level of secretion of estrogen from the follicles
    • raised levels of estrogen are necessary to:
    • - induce estrus behavior
    • - prime the anterior pituitary for the luteinizing hormone surge that causes ovulation
    • in the absence of mating, the follicles regress, estrogen levels fall, estrus suddenly ceases and the queen will stop calling
  15. Interestrus
    • shorter than anestrus - fine line between the two
    • period between one estrus and the next
    • absence of mating ... will come into season every 10-14 days
  16. Estrous cycle
    ~21 days long... 7 days of proestrus and estrus, plus 14 days of interestrus
  17. Anestrus
    • period during the winter where there is no ovarian activity
    • melatonin (pineal gland)
    • - secreted during the hours of darkness
    • - suppresses the release of gonadotropin releasing hormone (GnRH) from the hypothalmus
    • - the anterior pituitary gland does not release follicle stimulating hormone (FSH) and luteinizing hormone (LH) that would stimulate the ovaries
  18. Pro-estrus/early estrus
    • attracts male will vocalization and estrus odor - does not allow mating
    • may allow mating from several toms when she is receptive
  19. Ovulation
    • sucessive matings are important to trigger ovulation
    • vaginal stimulation at mating causes:
    • - reflex release of GnRH from the hypothalmus
    • - triggers luteinizing hormone (LH) release from the anterior pituitary
    • - LH is primed by the raised estrogen levels in estrus
    • - successive matings induce higher and higher peaks of LH until the ovulatory surge of LH occurs
    • successive matings must occur in a short period of time to avoid drops in LH levles (ovulatory peak not achieved)
    • LH surge lasts longer after multiple matings:
    • - optimum levels obtained if there are 4 matings within 2-4 hours
    • can occur without a mating taking place:
    • - physically induced by stroking the back and tail
    • - cats kept in colonies - pheromonal activity, activity of other females
  20. Ovulation rate
    • number of follicles ovulated varies
    • after ovulation, the queen goes out of estrus in 24-48 hours and a corpus luteum develops on each ovary
  21. Ovulation without fertilization
    • after ovulation:
    • - corpus luteum forms and produces progesterone
    • - will continue to develop in absence of fertilization for ~25 days - pseudocyesis
    • - life of the corpus luteum: non-pregnant cat shorter, dog longer
    • - after regression of the corpus luteum, short interestrus period, hormone levels fall back to normal
    • - FSH levels begin to rise again, queen will come back into heat (breeding season)
  22. Fertilization
    • can be fertilized immediately after ovulation
    • in uterine tubes (Fallopian tubes)
    • early embryos pass into uterine horns at 4-5 days
    • implantation occurs after 12-16 days - embryos evenly distributed in both uterine horns
    • gestation period - 64 days
    • corpus luteum - sole source of progesterone
    • day 20-30 placenta begins to produce relaxin (supports corpus luteum)
    • prolactin levels increase day 25-35 as relaxin levels are rising
    • - prolactin is luteotropic - helps to maintain corpus luteum
  23. Pregnancy diagnosis
    • abdominal palpation - at 3-4 weeks and after 6-7 weeks of gestation
    • transabdominal ultrasound
    • radiograph
    • relaxin levels
    • - pregnancy hormone
    • - produced by placenta
  24. Feline parturition
    • onset of parturition requires a live fetus
    • - secretions from fetus triggers a cascade of events leading to parturition
    • divided into 3 stages
    • usually complete within 6 hours of the onset of second stage labor
    • - should not be allowed to continue for more than 24 hours
  25. First stage labor
    • onset of increased uterine contractions
    • 6-12 hours, up to 36 hours
    • abdominal straining, queen will appear restless and uncomfortable
    • pre-parturient drop in BT not as obvious as in bitch
    • progesterone is converted to estrogen (by corticosteroids from fetus)
    • increased estrogen levels cause increased myometrial contractions leading to onset of parturition
  26. Second stage labor
    • begins when abdominal straining starts/becomes more pronounced
    • fetus in the pelvic canal - chorioallantoic membrane may rupture (reddish-brown fluid)
    • fetus expelled within amniotic membrane
    • queen breaks membrane, cleans newborn (neonate)
    • queen bites through umbilical cord
    • first kitten is usually expelled within an hour of second stage labor beginning
  27. Third stage labor
    • expulsion of fetal membranes - placenta
    • usually follows fetus within 15 miuntes
    • 2 or 3 fetuses may be born before placenta(s) appear
    • queen will often eat the placenta (may induce vomiting and diarrhea - V & D)
    • leave the queen to kitten in peace - check quietly once in a while to make sure everything's okay
  28. Care of the normal queen
    • delivered easily (usually)
    • queen's appetite returns within 25 hours after parturition
    • nursing queen - appetite may increase 2-4 times
    • colostrum produced by queen for 24-72 hours postpartum
    • queen may not leave kittens for 24 hours postpartum
  29. Postpartum disorders of the queen
    • retained placenta (oxytocin - make uterus contract)
    • uterine prolapse - uterus outside body
    • metritus
    • - inflammation of the uterus
    • - depression, anxiety, fever, neglect of kittens, sanguineous or purulent discharge
    • mastitis
    • - inflammation of the mammary glands
    • - warm, painful mammary glands; BT 103.5 - 106 degrees
  30. Disorders of pregnancy
    • infectious agents
    • - feline leukemia virus (FeLV)
    • - feline immunodeficiency virus (FIV)
    • - feline herpes virus
    • - feline infectious peritonitis (FIP)
    • - panleukopenia
    • - chlamydia
  31. Feline leukemia virus (FeLV)
    • "unfriendly disease"
    • embryonic reabsorption, fetal abortion, birth of infected kittens
    • viral particles cross placenta
    • test before breeding
  32. Feline immunodeficiency virus (FIV)
    • "friendly disease" - how its transmitted
    • transmitted in semen
    • passed transplacentally, nursing or grooming
    • stillborn kittens, arrested fetal development, abortion, delivery of FIV infected kittens
  33. Feline Herpes virus
    • abortion, fetal death, placental necrosis, persistent infection in kittens
    • transmitted via respiratory secretions
    • vaccinate for herpes (all breeding animals)
  34. Chlamydia
    abortion
  35. Vaccination of pregnant queen
    • do NOT vaccinate pregant queen for FVRCP
    • can cause cerebellar hypoplasia in kittens
  36. Nursing assistance
    • may need to break amniotic membrane
    • - kittens need to gain oxygen via lungs once placental exchange of oxygen has been compromised
    • fetal airways may be blocked with fetal fluids and mucus
    • - clear airways from obstructions to allow breathing
    • - gentle suction with a plastic pipette or gravity (carefully)
    • may need to cut umbilicus
    • - clamp with sterile forceps, tie with umbilical tape
    • - 2 cm of umbilical cord should be left attached to the kitten to avoid an umbilical hernia
    • - in C-section need to support forceps - can cause umbilical hernia
  37. Prevention of pregnancy
    • prostaglandin
    • - stimulate contractility of smooth muscle (abortion)
    • prolactin antagonist - cabergoline
    • - luteolysis
    • - suppresses progesterone (abortion)
  38. Manipulation of reproduction
    • induction of ovulation
    • suppression of estrus - progesterone
    • cats in colonies
    • constant daylight length of 16 hrs
    • - stops melatonin from suppressing hypothalmus, thus queens will come into season throughout the year
  39. The Tom
    sexually active the whole year
  40. Puberty in the tom
    • when the cat starts to produce spermatozoa in the ejaculate
    • - 8-12 months old usually
    • - 7-18 months
    • penis begins to develop cornified pappillae
    • - penile spikes - androgen dependent - develop as testosterone levels begin to rise
    • - spikes regress rapidly following castration
  41. Reproductive organs in the tom
    • testes
    • spermatic cord
    • epididymus
    • vas deferens
    • accessory glands
    • penis
    • prepuce
  42. Testes
    • spherical, ovoid structures
    • produce sperm (testosterone)
    • descend into scrotum at birth
    • - can retract into inguinal ring at will until about 4-6 months of age
    • - worry if not descended by approx 8 months
    • cryptorchidism - unilateral - descended testicle will produce spermatozoa
  43. Spermatic cord
    • extends from deep inguinal ring to the testes
    • comprises the ductus deferens, testicular artery and vein, etc
  44. Epididymus
    site of sperm maturation and storage
  45. Vas deferens
    excretory duct of the testes
  46. Accessory glands
    • prostate gland, bulbourethral glands
    • androgen dependent
  47. Penis
    located ventral to the scrotum
  48. Prepuce
    skin covering the free portion of the penis
  49. Mating
    • rapid
    • small amount (1 or 2 drops) of ejaculate (not fractioned)
  50. Secondary sex characteristics
    • thickened skin on cheek pouches and scruff of neck caused by increased subcutaneous connective tissue
    • - can bend 22 gauge needles
    • more muscular appearance of male (anabolic steroid effects of testosterone)
    • typical "tomcat odor"
  51. Manipulation of reproduction
    • castration
    • - removes the source of sperm and testosterone
Author
darlene.m.nelson
ID
120125
Card Set
vet-tech-therio-ch-11
Description
vet tech theriogenology chapter 11 reproductive anatomy and physiology of the cat set
Updated