Male Repro Flashcards
function of the testes
spermatogenesis and hormone production
spermatogenesis
spermatozoa produced in seminiferous tubules of testes
hormone production - testes
androgens (male sex hormones) produced in interstitial cells of the seminiferous tubules
- principal androgen = testosterone
what are testes
male gonads. repro cells formed in the testes, located outside of the body in the scrotum (need to be kept cooler than body temp to produce viable spermatozoa )
scrotum
cutaneous sac of skin outside of the body cavity which holds the testes in mammals - structure derived from skin and connective tissue from the abdominal wall to regulate temp
where do testes develop in utero?
inside abdominal cavity near the kidneys. they then move to the scrotum outside of the body cavity, need to pass through inguinal canal
are all testes located outside of the body?
some mammals and most birds have their balls on the inside
what are inguinal rings/canal
like some sort of spinchter, lil ring that closes around the testes - testes pulled through before birth or shortly after
gubernaculum
band of connective tissue that attaches testes to scrotum
balls dont descend in farm animal - consequences?
production and economic effects
- sterile
- no value as a breeding animal
cremaster muscle
passes through inguinal ring and attaches to scrotum, adjusts position of testes relative to the body - ensures viability for spermatozoa
seminiferous tubules
sperm production takes place in these u-shaped tubes.
1-25B a day in these tubes
testosterone production
in interstitial cells between semiferous tubules. responsible for male secondary sex characteristics/libido - enhanced muscle and bone development
testosterone implants
helps to increase gains, feed conversion, carcass weight/muscling
speeds bone development, decrease fat deposition
spermatic cord
suspends testis in scrotum, links them w the rest of the body, includes blood vessels and nerves etc - designed for heat control as well
seminiferous tubules structcture
coiled and tightly packed into oval shape of testis. long convoluted U. between the tubules are the interstitial cells which produce the hormones
tunica albuginea
beneath the tunics, encloses the testis. connective tissue. that contains the seminiferous tubules. protects and supports soft contents of the testis
epididymis - what
long tube that connects efferent ducts of the testis w the vas defrens, where spermatozoa are matured (10-15 days) before they can fertilize
epididymis sections
head, body, tail
- mature in head and body
- capable of fert once in the tail
- tail acts as storage site.
epididymis location
scrotum (what a funny sounding word)
sperm needs to be transported to urethra to jizz
ductus defines/vas deferens
tail of epidydimus to urethra
propels sperm using peristalsis to urethra
sperm road trip
produced in seminiferous tubule -> rete testis -> efferent ducts -> epididymis -> Vas deferens -> urethra
seminal fluid
manufactured by accessory glands (seminal vesicles, prostate gland, bulbourethral)
used to carry the sperm
alkaline to combat acidity
seminal vesicles
enters urethra at same area as bad defines, adds fluid to semen
prostate gland
surrounds urethra
urethra
located ventrally in the penis, usually carries urine. pumps out semen. can’t actively piss while humming.
penis!
breeding organ, made of muscle, erectile tissue, connective tissue. urethra runs down center
3 parts of the penis
roots, body, glands
penis roots
where it attaches to pelvis, has 2 bands of connective tissue.
muscles in the roots are trimmed during carcass dressing, dont eat the penis.
masculinity in relation to beef grading
graders will examine carcass for pronounced masculinity, look for ischiocavernous muscles, crest or neck muscles (increases w age), dark coloured/lean meat.
- beef from animals a pronounced masculinity may not be as tender, juicy, flavourful.
penis body
made of 2 bundles of tissue, firbrous tissue and blood-filled spaces.
non-erect - even blood flow into and out of tissue.
erect - inflow exceeds outflow.
penis tip
has rich supply of sensory nerve endings, sensitive to physical stim.
many species differences
retractor penis muscle
pulls penis beck to non-erect, s shape. bulls, rams, boars have more connective relative tissue than other species.
penis doesnt enlarge much w an erection
bulbourethral glands
in boars, very large, related to boar taint, attracts sows/ stimulates them to mate.
cryptorchids
in pigs called ridgelings, when movement of testes through inguinal canal is incomplete. infertile.
