Semen Collection - Anatomy & Physiology

Artificial Vagina

Introduction

  • Simulates the vaginal conditions of a female in oestrus.
  • Generally consist of
    • Outer casing of reinforced rubber
    • Rubber liner that can be lubricated
  • Temperature and pressure are controlled by water placed between the casing and liner.
  • One end is attached to a funnel-like cone that is attached to a collection vessel, usually a non-breakable test tube.


  • The desgin of the artificial vagina should accomplish the following:
    • Provide a suitable environment for stimulation of the glans penis.
    • Provide an environment that prevents damage to the penis.
    • Provide an environment that maximizes sperm recovery and minimizes sperm insult.


Advantages and Disadvantages of Using a Surrogate Stimulus

  • Males need training to mount a surrogate animal or 'dummy'.


  • Advantages of a surrogate animal:
    • Ease of cleaning
    • Minimizes risk of injury
    • Minimizes risk of disease transmission
    • Surrogate animals do not require feed input, housing or labour for maintenance.
    • Size can be easily adjusted to accommodate various males.
    • Can be mobile, so location can be changed with ease. This avoids changing location of the male - which is more dangerous, especially with Bulls.


  • Disadvantages of a surrogate animal:
    • Changing the location of teasers is difficult.
    • Requires previous training of the male


Species Differences

  • Stallion:
    • Leather outer casing equiped with a port to drain water.
    • Collection vessel and protective covering
    • Ideally, ejaculation takes place in a collection cone so that most semen drains directly into the collection vessel.
    • Surrogate stimulus used to collect semen from the Stallion is referred to as a 'phantom'.
      • Phantom has a biting belt to provide the stallion with a surface to bite during mounting thus providing a means for natural behaviour.
    • It is possible to palpate the urethra at the base of the penis to detect ejaculation. There may also be associated tail movements.
  • Bull:
    • Black casing
    • Rubber liner
    • Collection cone and collection vessel
    • Water is placed between the casing and the liner.
    • Proper temperature critical for successful ejaculation.
    • Protective covering placed over the cone and collection vessel to prevent cold shock of the semen.
  • Boar:
    • Bulb that can apply pressure to the artificial vagina.
      • High pressure is obligatory for stimulation of the glans penis and ejaculation in the boar.
    • Outer casing and liner
    • Protective covering that houses the collection vessel.
  • Ram and Buck:
    • Rubber casing with a valve through which water can be added or emptied.
    • Rubber liner and collection vessel.
    • Protective covering

Electroejaculation

  • Electrical stimulation of the accessory sex glands and the pelvic urethra.
  • Used in males of high genetic value that cannot physically perform mounting and ejaculation.
  • Electric probe is inserted into the rectum adjacent to the prostate.
  • Probe delivers a single electric current of around 15 volts under general anaesthetic.
  • Simulates nearby nerves, resulting in contraction of the pelvic muscles and ejaculation.


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