Veterinary Andrology and Reproductive Techniques

INDIVIDUAL MOTILITY

• Motility is the most common and extensively used tool for estimating the semen quality.
• The movement of individual sperm is taken into consideration while estimating the motility.
• To assess the individual motility diluted semen (diluted with physiological saline/3% sodium citrate/tris buffer/tris-egg yolk extender) is kept on a warm slide and covered with cover slip.

• Individual/initial motility assess the progressive movement of sperms.
• The assessment is made in diluted semen sample.
• The judgement should be made after estimating the sample in at least 3-5 different places at the centre of the slide.

• The slide is kept on the stage warmer of the phase contrast microscope and examined under high power. The various types of motility observed may be
  • Progressive movement - sperms with very rapid straight forward direction
  • Click here for video:
    • Initial motilty 10-20%,
    • Initial motilty 30-40%,
    • Initial motilty 60-70%,
    • Initial motilty 70-80% and
    • Initial motilty 80%
  • Circular movement - sperms with movement in circular path (Click here to view video)
  • Reverse movement - sperms moving in reverse manner
  • Oscillatory movement - sperms with jerky movement (Click here to view video )
• The progressively motile are sperms only taken into account while estimating the initial motility.
• The progressive sperms will cover a distance of 100-120 µ in a second.

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• Based on progressive motility, the semen samples are graded as follows.

S.No	Progressive motility	Grade
1	90 - 100%	Excellent
2	70 - 80%	Good
3	50 - 60%	Fair
4	30 - 40%	Por
5	0 - 20%	Very poor

• The semen collected after long period of time will have more dead sperms.
• The sperm with circular motility indicates cold shock to the sperms.
• The heat/thermal shock also affects the sperm motility.

A good semen sample should have an initial progressive motility of 70%.

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