Copulatory Behaviour - Anatomy & Physiology

Mounting

• Elevation of the front legs of the male to straddle the posterior region of the female.
• Learned behaviour

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Intromission

• Successful entrance of the penis into the vagina.

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Ejaculation

• The reflex expulsion of spermatozoa and seminal plasma from the male reproductive tract.
• Sensory stimulation, primarily to the glans penis causes a series of coordinated muscular contractions.
• Once intromission has been achieved, reflex impulses are initiated.
  • Neural impulses derived mainly from sensory nerves in the glans penis.
• Upon threshold stimulation, impulses are transmitted from the glans peinis by the internal pudendal nerve to the lumbosacral region of the spinal cord.
• Sensory impulses result in firing of nerves in the spinal cord.
• Forcing of semen into the urethra by nerves in the hypogastric plexus innervating target muscles.
  • Urethralis muscle
  • Ischiocavernosus muscle
  • Bulbospongiosus muscle
• Emission and ejaculation
  • Emission is the movement of seminal fluids from the accessory sex glands into the pelvic urethra so that they can mix with spermatozoa.
  • Emission occurs before and during ejaculation.

Dog

• Bitch in Oestrus spots bloody fluid just before the receptive stage.
• Male identifies the female.
  • Dogs are very aware of a bitch in oestrus and can detect them from 500-600 meters away.
• Bitch adopts receptive posture ('stands')
• Dog mounts and thrusts to achieve intromission.
• Intromission with a partially erect penis aided by the Os Penis
• Vulval erectile tissue of the bitch grips the penis.
• Penis achieves full erection (the 'Tie')
• Dog then turns to face the opposite direction (the 'Turn')
• Ejaculation

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Cat

• Queen 'calls'
• Male identifies female
• Queen crouches in lordosis
• Tom bites scruff of queen
• Tom mounts and thrusts to gain intromission
• If queen is in oestrus she will submit to allow full intromission.
• Tom ejaculates
• Female emits a yowl and rolls over, attempting to swipe the tom with her claws.
• Tom retires to a safe distance

For a video demonstration of copulation in the cat, follow either of the following links:

• Video of Copulation in the Cat
• Video of Copulation in the Cat