Wk 6- Feline Repro Queens

Feline Reproduction Overview

  • Discusses the key aspects of feline reproductive biology including the estrous cycle, pregnancy, parturition, and infertility.

Terminology

  • Female: Queen

  • Male: Tom

  • Cats are seasonally polyestrous, meaning they have repeated estrous cycles during a part of the year (similar to horses and sheep).

  • They are long day breeders, meaning they breed in the spring and summer.

  • Puberty starts as early as 4 months.

Estrous Cycle Phases

  1. Proestrus

    • Behavior: Attractive to males but will not allow mating.

    • Hormonal changes: Estrogen is high; no visible vulvar discharge.

    • Anatomy: Ovarian follicular growth.

    • Duration: 0-2 days, may not be observed.

  2. Estrus

    • Behavior: Allows mating; singing and affectionate.

    • Hormonal changes: Peaks of estrogen.

    • Anatomy: Ovarian follicular growth.

    • Duration: 2-19 days.

  3. Postestrus (Interestrus)

    • Occurs after estrus if ovulation does not occur.

    • Behavior: Not receptive to mating.

    • Hormonal changes: No production of estrogen or progesterone.

    • Anatomy: Regression of follicles.

    • Duration: 8-10 days, based on individual cat.

  4. Diestrus

    • Behavior: Not receptive to mating; occurs if ovulation has happened.

    • Hormonal changes: Progesterone production from corpus luteum (CL).

    • Anatomy: Corpora lutea (after follicles ovulate, becomes CL).

    • Duration: Pregnant - 2 months, non-pregnant - 40-50 days.

  5. Anestrus

    • Behavior: Non-receptive.

    • Hormonal changes: No estrogen or progesterone production.

    • Anatomy: Inactive ovaries.

    • Duration: Seasonal pattern; common in fall/winter.

Ovulation and Mating Behavior

  • Cats are induced ovulators, meaning ovulation occurs post-mating due to sufficient vaginal stimulation.

    • Causes GnRH release and LH surge.

    • Best chance is 4 matings in 2 hours

  • Mating involves:

    • Male (Tom) grasps the Queen's neck.

    • Vocalizations by the Queen during mating.

    • Following mating, the Queen exhibits behaviors like rolling and licking, indicating aggression towards the male post-copulation.

Persistent Estrus

  • Repeating follicular waves with overlap.

  • Estrogen-induced signs of “heat” do not subside.

  • Causes:

    • Estrogen-secreting follicular ovarian cysts

    • Ovarian neoplasia

      • Granulosa cell tumor (GCT)

    • Exogenous hormone exposure

Pregnancy and Gestation

  • Length of gestation: 56-71 days (Average: 65-67 days).

  • Superfecundation: Offspring in a litter may have different fathers due to fertilization by multiple males.

  • Diagnostic indicators of pregnancy include:

    • Relaxin hormone presence in the blood and urine after 28 days.

    • Physical changes including mammary gland development (3 weeks).

    • Palpation can confirm pregnancy as early as 2-3 weeks post-mating.

      • Palpate enlarged uterus at 3.5 weeks.

      • Can palpate fetal heads at 7 weeks.

    • Ultrasonography can confirm as early as 2.5 weeks

      • 3mm anechoic vesicles (fluid-filled) past 9 days.

      • Fetal heartbeat past 16 days.

      • Limb buds at 20 days.

      • Bladder at 30 days.

      • Kidneys at 40 days.

      • Renal cortex and medulla at 50 days.

    • Radiology can be used to see skull after 38 days.

      • Fetal molars at 56-63 days.

      • Crown rump length can be used to estimate the gestational age.

  • Queens can show estrus during pregnancy.

  • Placenta: Zonary, Endotheliochorial, Deciduate

Nutrition During Pregnancy

  • Switch to kitten chow by 2/3 gestation (need taurine).

  • Increased feeding:

    • 1.5x the maintenance amount during second trimester (4-6 weeks).

    • 2x the maintenance amount during last trimester (>6 weeks).

Parturition (Kittens Birth)

  • Typically similar to sheep behaviors:

    • Stage I: Nesting and pacing behavior.

    • Stage II: Active labor, which may last hours to a day.

    • Stage III: Expulsion of fetal membranes.

  • Dystocia (difficult birth) is rare but may occur in certain cat breeds (Devon Rex and short and long headed breeds).

Infertility

  • Causes of feline infertility can include:

    • Estrous cycle issues, mating issues, infections, anatomical or chromosomal abnormalities.

  • Diagnostic tools include abdominal ultrasound, exploratory surgery for anatomical issues, and karyotyping.

Key Concepts Recap

  • Understanding of the feline estrous cycle phases is vital for proper breeding management and feline health.

  • Be aware of the hormonal cycles and their effect on behavior.

  • Recognize symptoms of pregnancy and prepare for parturition correctly.

  • Infertility can often be mitigated through proper diagnosis and intervention strategies.