Breeding Shed Lab Equipment
By: Nadine Hershey
The equipment contained in the
breeding lab at Penn
State is very functional
for the work done. Stallions at Penn
State are collected and
semen is either used fresh or extended, cooled, and shipped or stored for
later evaluation.
To process the sperm, many
different types of equipment are used. An incubator is used to keep equipment
at a constant body temperature. A
hemacytometer is used to occasionally standardize measures, but on a regular
basis the concentration of sperm in the ejaculate is measured using the
“Counter Point” by Hamilton Research Institute. The motility and progressive motility are observed using a microscope
and measured subjectively by an experienced technician. All of the devices used in the breeding
shed have positive and negative aspects, which will be further discussed.
Table of Contents:
1. Incubator
2. Microscope
3. Computer Analysis
4. Counter Point
5. Hemacytometer
 INCUBATOR
(see figure 1)
·
This is the incubator
that is utilized by Penn
State.
·
A benefit of this
incubator is that it is large enough for most breeding supplies.
·
This incubator could
possibly be more organized with extra shelving, but the large open space
allows for keeping the AV warm prior to filling.
·
Inside the incubator
is a thermometer for thermoregulation purposes. The incubator is usually set at about 37 degrees Celsius.
·
The purpose of the
incubator is to keep the processing tools at the stallion’s body
temperature.
·
The heating device in
the incubator should be precise to make sure the pipettes, slides,
coverslips, etc are exactly at, not above or below body temperature.
·
Attention to
maintaining supplies at the proper temperature helps to decrease the
likelihood of cold shock to the sperm.
Figure 1
Microscope:
·
This is the
microscope that the technicians at Penn
State use to evaluate
motility (see Figure 2)
·
Progressive motility
is observed directly, which allows for quick and easy evaluation
·
The semen is usually
evaluated under the 10X objective with a 10X eyepiece, so total magnification
is 100X
·
Problems with this
motility evaluation technique begin with the microscope not having a heated
stage. The change in temperature
could affect the sperm negatively. A
stage heater is commercially available.
One must be careful when purchasing a stage heater, however, because
the heating unit may put off heat in one central area only. The heat must be evenly distributed throughout
the stage.
·
Also, if multiple
individuals are measuring motility, the results are subjective.
Figure 2. Microscope
Alternative to simple subjective sperm motility analysis:
COMPUTER ANALYSIS
(see figure 3)
- A computer software device can be utilized to measure
progressive motility. A camera
projects the view of the sperm through the oculars to a computer screen
where the software objectively analyzes the movement of the sperm.
1.
If the sperm cells
have a very high velocity, they may be measured as moving in a circular
tract, which is not counted as progressive.
2.
The software and
equipment are extremely expensive, and most labs cannot justify the expense.
Figure 3
Counter
Point
(see figure 4)
- This is the Counter Point made by Hamilton
Research Institute.
- Penn State
utilizes this instrument to measure the number of sperm per
milliliter.
- The instrument gives us an accurate estimate of
sperm concentration that is quick and relatively easy by comparing the
density of sperm in the ejaculate to a set of standards.
Figure 4
HEMACYTOMETER
(see figure 5)
- Prior to the densimeter, semen concentration
was determined at Penn
State by using a
hemacytometer.
- This involved counting sperm in the well of a
slide using a gradient (the red dots on the picture mark the 5 squares
on the grid where sperm numbers are manually counted).
- Determining concentration using this method on
a regular basis was a tedious task that slows down the semen processing
procedure, but it can be used to confirm values determined using the
Counter Point.
Figure 5
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