Vie CONG. INTERN. REPROD. ANIM. INSEM. ARTIF., PARIS, 1968, VOL. Ii

The Preparation of Dairy Goat Semen for Freezing

C.A.V. Barker
Ontario Veterinary College, University of Guelph
Guelph, Ontario, Canada.

The preparation of dairy goat semen for freezing begins with the
preparation of the male for ejaculation and the correct use of the
artificial vagina.

The males should be trained to accept the presence of the
collector who kneels on the floor beside the rear quarters of the
teaser female or intersex (restrained in a stanchion). Quiet
surroundings are essential. One or two false mounts are conducive
to a good semen volume. Because bucks have a very short reaction
time the collector must be prepared to work quickly, positioning
the artificial vagina rapidly and holding it correctly. If the
collecting tube is shaken at or after ejaculation has occurred there
may be a deleterious effect on semen motility. Only semen with a
very high initial motility evaluation should be used for freezing.

Advance preparation should be made for evaluating the semen,
extending, glyerination and storage in suitable containers so that a
minimum period of time occurs between collection and freezing. Goat
semen is apparently a fragile substance after leaving the animal
body, severely affected by sudden temperature change and agitation.
It, therefore, is important that temperature control of the semen
collection room, processing laboratory, glassware contacting the
semen (whole and diluted semen) and careful handling be closely
watched. It is believed preferable to perform initial motility
examinations and extensions in a room at about 27°C. Extenders,
pipettes, mixing tubes should always be kept as near 35°C as possible.

Immediately after collection the ejaculate should be evaluated
microscopically and extension performed. An extender we have used
successfully is sterile skimmed milk. This is held in a water bath
at 35°C and extension made immediately the motility has been
evaluated. In the same water bath should be the 14% glycerinated
sterile skimmed milk. Glycerination should begin as soon as possible
after the initial extension, preferably in less than an hour. This
may be done at a room temperature of about 22°C or in acold room
at 5°C. Fractional addition in four increasing amounts during a
period of about 45 minutes is a satisfactory procedure.

The equilibration should be short, about 2 hours or slightly
longer, during which time the extended samples will cool slowly to
59CsSThe samples may be equilibrated either before or after placing
in the final container. We have used only 1.5 cc ampoules as
containers.

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