Transcript Semen Analysis

Semen Analysis
Clinical Pathology
Semen Collection
Semen is often collected into an artificial
vagina, usually while a teaser bitch is
present.
 An artificial vagina may be made of latex
or disposable plastic.
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May use electoejaculation in which a
probe is attached to the pelvic nerves to
stimulate ejaculation.
Semen (3 fractions)
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1st- mainly prostatic fluid, few sperm
– Released during the period of vigorous thrusting
2nd- Sperm rich portion of ejaculate
 3rd- Mainly prostatic fluid, few sperm, majority of
total volume of ejaculate.
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– Buck, bulls, tom, ram you should collect all three
– Stallions, dogs, boars- collect 2nd and 3rd portions
seperately
Semen Handling Techniques
Avoid marked temperature changes
 Avoid exposure to water, disinfectants
 Use clean, dry, warm equipment (37 C or
98 F)
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– Slides, coverslips, pipettes, stains.
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Process soon after collection
Semen Evaluation
Color and consistency (normal is milky and
moderately viscous)
 Volume
 Wave motion/sperm motility
 Spermatozoa concentration
 Morphology
 Ratio live:dead
 Presence of foreign cells/material
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Volume of Ejaculate
Measured in volumetric flask
 Method of collection affects volume
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– Electroejaculation- volume is larger
– Teasing with a female-volume is larger
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Species variation
– Dogs: 10-40 ml
– Stallion: 65 ml
– Tom: 0.5 ml
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Volume does not necessarily correlate with
fertility
Sperm Motility
Motility correlates with fertility
 Improper handling can affect motility
 Evaluate immediately after collection
 Place a drop of semen on a warm slide,
immediately cover with coverslip
 Dilute with warm saline if high
concentration of sperm
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Classes of Sperm Motility
Can be classified as good, very good, fair,
or poor.
 Normal sperm should have greater than
70% motility
 Examine under 100 x, may need to dilute
concentrated samples
 Poor is when there is less than 40%
motility
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Wave Motion
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Under low power 40x, look for swirling
– Progressive motility- sperm are moving
around all over slide
– Non-progressive motility- sperm are only
swimming in a similar pattern
Sperm Concentration
Most important characteristic
 Dilute a portion 1:100 with saline or red cell
Unopette.
 Using a hematocytometer, count total of sperm
in the central grid
 Multiply the number by 2 million
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Boars/Stallions: 150 M/ml
Bulls: 1200 M/ml
Dogs: 300 M/ml
Cats: 1700 M/ml
Live:Dead Sperm Ratio
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Place 1 drop eosin/nigrosin stain (make sure it is
warm) and mix gently with a drop of semen on a
warm slide.
After several seconds, smear like blood smear.
Live sperm resist staining-appear white against a
blue-black background
Dead sperm take up the eosin and stain pinkish
red
Examine and observe 200 cells
Sperm Morphology
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Can examine on eosin/nigrosin stained smear
Other stains: india ink, H&E, Wrights
Observe 100-500 cells
Record % of abnormal cells
Divide problems into head, neck, midpiece, and
tail problems.
Primary abnormalities occur during sperm
production.
Secondary occur from storage in the epididymis
until the smear is made
Double headed Sperm
Misshapen Head
Elongated Head
Pear shaped head and bent
midpiece
Proximal Droplet
Distal Droplet
Detached Head
Bent Tail or Midpiece
Coiled Tail
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http://www.vivo.colostate.edu/hbooks/pat
hphys/reprod/semeneval/conc.html