Animal Dairy Science 434 Comparative Male Anatomy Testis

Animal / Dairy Science 434 Comparative Male Anatomy

Testis Species Testis Wt. % Of Orientation (grams) Body Wt. bull 300+ . 03 vertical ram 250 . 3 vertical boar 350 . 2 oblique stallion dog rabbit human 200 25 2. 5 25 . 03 horizontal . 2 oblique/horz. . 1 vertical. 03 vertical

Reproductive Organs of the Bull Rectum Seminal Vesicles Prostate Cowpers Gland Ampulla Bladder Vas Deferens Glans Penis Retractor Penis Muscle Sigmoid Flexure Caput Epididymis Scrotum Prepuce Testis Gubernaculum Cauda Epididymis

Reproductive Organs of the Bull Vertical

Ram Vertical

Boar Oblique

Anatomy of the Dog Oblique to Horizontal

Stallion Horizontal

Human Vertical

Testis Orientation Bull Tail Head

Testis Species Testis Wt. (grams) bull 300+ . 03 vertical ram 250 . 3 vertical boar 350 . 2 oblique stallion 200 . 03 horizontal 25 . 2 oblique/horizontal . 1 vertical . 03 vertical dog rabbit human 2. 5 25 % Of Orientation Body Wt.

Seminal Vesicles Ram Ampulla Bladder Vas Deferens Pelvic Urethral Muscle Cowper’s Gland Prostate Bulbospongiosus Muscle No Body of the Prostate

Cowper’s Gland Seminal Vesicles Prostate Vas Deferens No Ampulla Large Cowper’s Bulbospongiosus Muscle Pelvic Urethral Muscle

Seminal Vesicles Prostate Cowper’s Gland Ampulla No Disseminate Prostate Vas Deferens Bulbospongiosus Muscle Pelvic Urethral Muscle

Human No Disseminate Prostate

Anatomy of the Dog No ampulla, seminal vesicles, disseminate prostate or Cowper’s gland

Cat (Tom) Reproductive Tract Vas Deferens Prostate Cowper’s Gland Corpus Cavernosum Crus Penis Ampulla Glans Penis No Seminal Vesicles or Disseminate Prostate

Cat (Tom) Reproductive Tract Note how close the cowper’s gland is to the penis in the cat.

Cat Glans Penis

Feline Anatomy: Erection and Mating

Accessory Glands Species Seminal Vesicles Prostate. Cowper's body disseminate bull ++ + ram + - + ++ boar +++ + + +++ stallion +++ ++ - (+) dog - ++ - Cat - ++ - human + ++ - +

Accessory Gland Secretions Species Seminal Prostate Cowper's Vesicles Bull No Clot Material Ram No Clot Material Boar Stallion Gel Mucous Dog Human No Clot Material Clot-Enzyme

Penis Types Muscular-Vascular Fibroelastic

Human Penis Cross Section Blood Vessels Corpus Cavernosum Muscular. Vascular or Fibroelastic? Corpus Spongiosum Large Veins Urethra

Internal Prepuce Raphe Urethral Process Stallion Bull Free End of Penis Glans Penis Human Filiform Appendage Ram Cat Boar No picture Dog

Comparison of Penis Types

Human

Dog Anatomy Bulbus Glandis

Sigmoid Flexure Boar Bull Fibroelastic Penis

Muscular. Vascular Penis Type Stallion

The Penis Species Sigmoid Type Erectile Glans Flexure Tissue Bull Ram Boar yes yes FE FE FE + + + Glans not distinct Stallion Dog Cat no no no MV MV MV Large Glans+ Human no MV +++ +++ Spines +++ Large Glans

Erection and Ejaculation Characteristics Male Speed Erection Ejac. Time Semen Sperm Vol. Conc. bull rapid short medium med. -high medium rapid short small high medium boar rapid long large low high stallion slow moderate large low medium dog slow long large low cat slow moderate small high low human slow moderate medium low Large Testes = high sperm numbers Large accessory glands = large volume of the ejaculate with lower concentration of sperm Sperm Num.

Seminiferous Tubule Primary Spermatocyte Spermatogonium Sertoli Cells » Support spermatogenesis Myoid Cells Secondary Spermatocyte Leydig Cells » Testosterone synthesis Round Spermatids Basement Membrane Capillary

Seminiferous Tubules

Seminiferous Tubule

Sertoli Cell

Interstitial Tissue (space) Capillary Leydig Cell

Capillary Leydig Cells

Epididymis Principal Cell Basal Cell Stereo-Cillia

Cauda Epididymis near Vas Deferens

Sperm Smooth Muscle Vas Deferens