Male Repro Flashcards
Describe what male fertility requires.
- spermatogenesis
-endocrine reg
-thermoreg
-spermatocytogenesis (mitosis & meiosis)
-spermiogenesis (morphological) - delivery system
-accessory gland
-erection, ejaculation
-libido
Describe the scrotum.
-blood supply = external pudendal a.
-nerve = genitofemoral n.
-lymph drain = superficial inguinal
-scrotal skin = thin, sweat gland, tunica dartos
Describe the testes.
-oval, lateral
-vertical in bull/ram & horizontal in dogs, cats, horse, pig
-testicular a.
-testicular v. = pampiniform plexus
-lymph drain = lumbar LN
Describe the testicular thermoregulation.
-testes 4c lower than body temp
-pampiniform plexus = countercurrent arterio-venous exchange
-cremaster muscle
-whole bod response = rise in temp = rise in respiratory rate
Describe pampiniform plexus.
-thermoregulation = countercurrent
-conc of T4 = countercurrent
-reduced pulsatility = long & contorted
Describe the testis.
-seminiferous tubules
>sertoli
>spermatogenic cells
-rete testis
-efferent ducts
-interstital cell of leydig = make T4
Describe the blood testis barrier.
-mature germ cells
-protect germ cell from immune system
-nonfenestrated
-BM
-junction between Sertoli cells
Describe the epididymis.
-head, body, tail (tail has fertile sperm)
-sperm maturation, storage, transit (2 wks)
-androgen (T4) dependent
Describe male accessory glands & their function.
-ampulla, prostate, vesicular gland, bulbourethal gland
(Dog only has prostate)
FUNCTION: produce seminal plasma
Describe the penis.
-2 types:
1. Musculocavernous = stallions, dog, cat (blood engorgement)
2. Fibrous = ruminants, boar, camelids (dont need blood)
-nerve = dorsal n. (Responsible for ejaculation)
-corpus cavernosum = body of penis
-corpus spongiosum = surrounds urethra
Describe the endocrinology of male reproduction.
-AMH
-GnRH
-LH
-FSH
-T4
-E2
-INH
Describe the 7 hormones found in male reproduction.
- AMH
-low level postnatal
-made by sertoli
-increase in cryptochoridism - LH
-leydig = T4 - Prolactin
-pituitary
-enhance LH - FSH
-act on sertoli = promote protein synthesis (ABP) - Androgen binding protein (ABP)
-secreted in seminiferous tubules (high conc of T4) for epididymus function - T4
-made by leydig
-neg feedback = decrease GnRH & FSH & LSH by pituitary (surge) - DHT
-more potent than testosterone
Describe seasonality.
gonadotropin conc decrease in non breeding season due to photoperiod on pineal gland by melatonin
Describe the hypothalamic centers.
-tonic (males) = regulate low GnRH pulses
-surge (females) = respond to high E2 & release high GnRH pulse
*regulate by levels of T4 & E2
Describe spermatogenesis.
-testis & epididymis
-spermatocytogenesis = form spermatids from spermatogonia
-spermiogenesis = spermatid to spermatozoa
-60d
-waves, stages, cycles
*’spermatogonia’ ->MITOSIS-> primary spermatocytes ->MEIOSIS I-> 2 ‘secondary spermatocytes’ ->MEIOSIS II-> 2 spermatids ->MORPHOLOGICAL-> 4 ‘spermatozoa’
