Anatomy
Brian Reproduction- Bolt Clemson University Animal & Veterinary Sciences
AVS 150
Female Reproductive System Anatomy
AVS 150
Cow
Uterus type:
Duplex
oppossum, mouse, rabbit 2 cervixes, no uterine body, 1 or 2 vaginas
Bicornuate
cow, ewe, mare, sow, bitch 1 cervix, uterine body, developed uterine horns, 1 vagina
Simplex
primate 1 cervix, uterine body, no uterine horns, 1 vagina
*Sow has extremely long uterine horn (enables multiple births)
3.2 Reproduction- Anatomy
3
AVS 150
Sow
Broad ligaments: Hold uterine horn In place
3.2 Reproduction- Anatomy
4
AVS 150
Mare Cervical differences:
Cow, Ewe
annular rings, ewe has more obstacles
Mare
longitudinal folds
Sow
interdigitating prominences
3.2 Reproduction- Anatomy
5
AVS 150
3.2 Reproduction- Anatomy
6
AVS 150
Anatomy of Female Reproductive Tract
Vulva outer covering Labia interior of vulva (acts as a seal) Clitoris similar to penis in males, has no purpose Vagina interior, bladder stems off Cervix beyond vagina, made of cartilage Uterus (uterine body, uterine horns) semen deposited in uterus just beyond cervix during A.I. (cattle).
Bull, sheep ejaculation in vagina Boars ejaculate in cervix corkscrew penis
3.2 Reproduction- Anatomy
7
AVS 150
Anatomy of Female Reproductive Tract, cont.
Oviduct extends from horns to ovaries
1st part: isthmus 2nd part: ampula 3rd part: infundibulum
Ovaries located at the ends of the infundibulums Covers the ovaries Acts as a funnel and catches eggs as ovulation occurs
Ampulary-isthmic junction between the isthmus and the ampulla (where fertilization occurs)
3.2 Reproduction- Anatomy
8
AVS 150
Oviduct
3.2 Reproduction- Anatomy
9
AVS 150
Anatomy of Female Reproductive Tract, cont.
Uterotubal junction
Junction between the uterine horn and oviduct Acts as a door that pulsates, helps to ensure survival of the fittest (sperm) Thousands of sperm will arrive at the "door" but only a few hundred will be allowed to pass through
3.2 Reproduction- Anatomy
10
AVS 150
Ovaries and Eggs
Ovary: Gametogenic - produces ova and endocrine - produces hormones
Estrogen Progesterone
Females born with only so many eggs
3.2 Reproduction- Anatomy
11
AVS 150
Three Basic Structures of the Ovaries
Follicle: blister-like structure on ovary that contains maturing egg
When fully mature, follicle ruptures & releases egg
Corpus luteum: active tissue that develops on the ovary at the site where an ovum has been shed
If conception occurs, tissue becomes functional, producing progesterone
Corpus albicans: tiny scars that remain after complete regression of the earlier lutea; forms after the CL lyses
3.2 Reproduction- Anatomy
12
AVS 150
see Fig 10.5, p 173
Follicles are classified as normal (healthy) or atretic (degenerating)
3.2 Reproduction- Anatomy
13
AVS 150
Uterus
3.2 Reproduction- Anatomy
14
AVS 150
Male Reproductive Tract Anatomy
AVS 150
Male Anatomy
Mammalian testes (testis, singular; Latin = to testify or witness Paired Originate near kidneys Descent by birth except whales, dolphins, pachyderms, armadillo, birds continuous breeding scrotum seasonal breeding ascend / descend inguinal canal 4 to 8 degrees cooler than body temperature Cremaster muscle skeletal muscle, spermatic cord short term, fear / excitement Tunica dartos muscle smooth in scrotum long term contraction, function lost with castration Blood vessels as heat exchanger Pampiniform plexus necessary for spermatogenesis not testosterone production
NOT like ovaries do not remain in body cavity all potential gametes not present at birth
3.2 Reproduction- Anatomy
16
AVS 150
3.2 Reproduction- Anatomy
17
AVS 150
3.2 Reproduction- Anatomy
18
AVS 150
Nitric oxide (gas, NO) stimulates guanylate cyclase converts GTP to cGMP cGMP relaxes corporal sinusoid smooth muscle enlarge with blood, increase pressure
PDE5 phosphodiesterase 5 converts cGMP to GMP increased vascular tone outflow of blood -> flaccid
Viagra (sildenafil) blocks action of PDE5 prolongs cGMP effect would have no effect if NANC were not producing cGMP
3.2 Reproduction- 150
3.2 Anatomy
19
AVS Reproduction- Anatomy
20
AVS 150
Testes
Gametogenic produces sperm cells
(seminiferous tubules)
Endocrine produces hormones Testosterone (Leydig cells)
3.2 Reproduction- Anatomy
21
AVS 150
3.2 Reproduction- Anatomy
22
AVS 150
Epididymus
Tube (duct) leading from the testis Collects & stores sperm, which migrate through Slowly; divided into head, body, tail (caput, corpus, cauda) Tail = primary site of sperm storage. Head & Body: prepare sperm (maturation)
3.2 Reproduction- Anatomy
23
AVS 150
Secondary Sex Organs
Vas Deferens Tube passageway for sperm/ejaculate mix
Connects epididymus & urethra Contracts with peristaltic effect, causes ejaculation
When cut = Vasectomy. Urethra common passage for semen and urine. Penis organ of copulation.
3.2 Reproduction- Anatomy
24
AVS 150
Penis
Fibroelastic bull, ram, boar More cartilaginous (doesn't require as much blood
flow for erection S-shaped, sigmoid flexure when relaxed straightens when erect. Retractor penis muscle restores sigmoid flexure.
Vascular stallion, dog, cat, man
Enlarged by engorgement of blood. Dog has os penis bone.
3.2 Reproduction- Anatomy
25
AVS 150
Penis - Copulatory organ
Shaft
corpus cavernosum spongy, erectile tissue - majority corpus spongiosum around penile urethra
Glans penis sensory, homologue of clitoris (female) Variable cat (tom) spines, disappear with orchidectomy pig (boar) corkscrew
Prepuce (sheath, foreskin)
3.2 Reproduction- Anatomy
26
AVS 150
Accessory Sex Glands
All contribute to seminal fluid volume, support nutrition of sperm and act as buffers. Seminal vesicles paired glands, attached to urethra near bladder, produce large volume of fluid; flushes urethra; acts as vehicle for sperm transport; also contains fructose. Prostate gland compound gland lying over urethra at neck of bladder; secretions stimulate sperm activity.
Bulbouretheral (Cowper's) glands lie below prostate on either side of urethra; produces lubricating and cleansing fluid just prior to ejaculation.
3.2 Reproduction- Anatomy
27
AVS 150
Protective, Supporting Structures
Scrotum thermosensor, radiator, protective sac Spermatic cord contains testicular artery, spermatic vein, nerves, vas deferens, external and internal cremaster muscle
External cremaster & Tunica dartos muscle regulates temperature by moving testes closer to or farther from body wall. Pampiniform plexus heat exchange, testosterone exchange, pulse pressure eliminator Sheath correct angulation desired
3.2 Reproduction- Anatomy
28
AVS 150
Repro tract similar to bull. Glans penis has hairlike appendage (~1")
3.2 Reproduction- Anatomy
29
AVS 150
Boar reproductive tract
Compare to bull: Large testes, inverted with tail of epididymus uppermost. Large bulbourethral glands (gelatinous secretion). Pronounced preputial pouch (contributes to boar odor).
3.2 Reproduction- Anatomy
30
AVS 150
Stallion
Compare to bull, boar: Nearly horizontal testes. Vascular penis; no sigmoid flexure.
3.2 Reproduction- Anatomy
31
AVS 150
Rooster
Testes inside body cavity.
No penis. Hen & rooster invert cloaca; rudimentary copulatory organ of rooster transports sperm.
Figure 10.13
3.2 Reproduction- Anatomy
32
AVS 150
Sperm production
Controlled by FSH (follicle stimulating hormone) Testosterone production stimulated by LH (leutinizing hormone) Some seasonal effects (especially stallion)
Spermatgenesis (sperm maturation): 50 60 days
3.2 Reproduction- Anatomy
33
AVS 150
Cycle of sperm production 45 to 61 days depending on species consequences of a problem
Sperm / gram (106) Sperm / day (109)
Man Rooster
4 100
0.13 2.5
Stallion
Bull Boar
3.2 Reproduction- Anatomy
16
11 beef 12 dairy 12
34
5
6 7.5 16
AVS 150
Semen Volumes and Sperm Concentrations
Species Bull Ram Buck goat Stallion Boar Rooster Volume (mL) 2 - 10 0.7 2.0 0.6 1.0 30 - 300 150 - 500 0.2 1.5 106 sperm Per mL 300 -2000 2000 - 5000 2000 3500 30 - 800 25 - 300 0.5 - 60
Sperm -> acrosome, head, midpiece, tail mature in epididymis motile and fertile
3.2 Reproduction- Anatomy
35
AVS 150