Semen Collection
in dogs
Semen is collected from dogs
for breeding soundness exams, as well as for artificial insemination.
Semen collected for insemination can be used fresh, or can be
cooled and shipped to another location. Canine semen can also
be frozen, allowing long term storage. Another indication for
collecting semen is to obtain prostatic fluid for culture or
cytology in cases of suspected prostatic disease.
Semen Collection
Semen can be collected from
most males without the need for a teaser bitch, particularly
if the male has had semen collected previously. However, use
of a bitch will almost certainly expedite the procedure and
allow more sperm to be harvested. Ideally the teaser should
be in estrus, but considering the length of the canine cycle,
that is often difficult to arrange, and a friendly, non-estrus
bitch will often serve the purpose. If a bitch is used, she
should be controlled with her rear quarters facing the male.
An alternative means of stimulating
the male is to present him with a vaginal swab from an estrous
bitch - for convenience, a number of such swabs can be prepared
from an estrous bitch and stored frozen until needed.
Canine semen is collected using digital pressure and massage.
Most failures arise because the male is shy or otherwise intimidated.
It helps to perform the collection on a non-slip surface such
as a carpet. If the male appears nervous or this is his first
time, a teaser bitch may help considerably.
Semen is collected without allowing
the male to mount. A latex collection cone with an attached
tube is commonly used. As an alternative, some people prefer
to use a disposable baby bottle liner. Both collection tools
are shown.
Collecting semen from dogs is
not difficult, but like many things, is much easier after you've
done it a time or two. The basic process is conducted in the
following series of steps:
- Grasp the prepuce and pull/push it back
to expose the tip of the penis.
- Slide the collection cone over the protruding
penis and slide it over the penis, pushing the prepuce back
over of the bulbis glandis (see images below).
- Lock your fingers in a ring around the
penis, essentially holding the bulbis glandis inside your
fist.
- Apply pressure with forward and backward
movement; in most cases, the male will begin to thrust back
and forth.
- Watch for semen to flow in the collection
tube. Most dogs stop thrusting as they begin to ejaculate.
- Continue to apply pressure until you observe
a crystal clear fluid (prostatic fluid) begin to flow into
the collection tube; at that time you can gently slide the
collection cone off the penis.
 |
 |
 |
|
Retraction of the prepuce |
Collection cone on and pressure being
applied |
After collection. Note the engorged bulbus
glandis |
A rather common problem encountered
in collecting canine semen is that the male develops an erection
prior to being able to extend the penis and bulbus glandis out
of the prepuce. Semen can be collected in this manner, but not
as easily. If this happens, simply take the male a distance
away to let him calm down, then try again.
Semen Evaluation
Dogs ejaculate semen as three
distinctive fractions. By using a clear plastic collection tube,
the delivery of these three fractions is easily monitored.
- Pre-sperm fraction: this is usually
slightly cloudy in appearance and has a volume of roughly
0.5 to 2 ml.
- Sperm-rich fraction: in normal dogs,
this fraction is distinctly milky in appearance.
- Prostatic fraction: this fraction
is recognized as a crystal clear fluid flowing into the
tube, and ejaculated slowing over a prolonged period of
time. In most cases, collection is stopped as soon as this
fraction is recognized.
Normal ranges for seminal characteristics
in dogs are described in the following table:
| Parameter |
Normal Values |
| Ejaculate volume (without prostatic fraction) |
1-6 ml |
| Sperm concentration |
100-500 million/ml |
| Total sperm per ejaculate |
300-2000 million |
| Progressive motility |
Greater than 70% |
| Morphology |
Greater than 80% normal |
article courtesy of CSU |