Semen Storage	"A-Z" INDEX &   SEARCH Short Term Storage of Honey Bee Semen

Honey Bee Semen can be transmitted by post using readily available glass capillary tubes 100 mm in length and with a bore cross sectional area of 1 sq mm, which gives a convenient 100 µl volume. In practice the actual maximum volume of semen is around 85 µl as there is a plug of petroleum jelly in each end of the tube that acts as both a stopper and air excluder.

Petroleum jelly is known by various terms in various countries and can be translated as Petrolatum, Vaseline or PetJel.

The information reproduced below is partly taken from a leaflet that possibly was part of the instructions that come packed with Harbo syringes. The Harbo device is a micrometer driven syringe, however the text has been modified to suit any type of equipment or hydraulic saline driver.

The petroleum jelly seal that plugs each end of the semen filled capillary should be in direct contact with the semen without any air space.

Sealing the semen storage tube

1. After semen has been collected, draw the semen up into the capillary tube and remove, from the capillary, the glass tip and latex connector used for collection.
2. Remove the capillary tube from the collection mechanism, but do not detach it from the flexible tube connected to the micrometer driven syringe or other saline driving device.
3. Use the micrometer or driver to push the semen flush with the end of the capillary tube.
4. Detach the semen filled capillary tube from the syringe.
5. Petroleum jelly is then forced into the capillary tube from the end flush with semen. This is accomplished by holding the capillary tube vertical and forcing petroleum jelly (which has been placed on a flat surfaced spatula) into the tube which will push the semen column along making an airtight seal.
6. When the capillary tube contains approximately 7 mm. of petroleum jelly, slide the capillary tube sideways across the flat spatula to retain the seal.
7. Re-connect the sealed end of the capillary tube to the hydraulic driver and push the column of semen flush with the other end of the tube. If the tube is only partially filled it may be cut, leaving enough space for a seal at each end.
8. Repeat the above procedure to seal the second end of the capillary tube.

Storage

For best results honey bee semen should be stored at 21°C. Avoid direct sunlight and temperature extremes. Do not refrigerate the semen.

Removing a seal from a tube  (after transport or storage)

1. Assemble the syringe or holding device without the glass tip, leaving both petroleum jelly seals in the semen filled capillary tube. No air space is required, or desired, between the petroleum jelly and the saline driving solution when assembling the syringe. The petroleum jelly seal will serve to separate semen and solution, use it in the same manner as an air space.
2. After assembly of the syringe and before the tip is connected, use the micrometer or other driving device to push out the seal at the tip end of the capillary tube. The seal at the other end of the tube will remain in place during insemination, but will be displaced along the tube like a piston.
3. Take up several microlitres of saline solution leaving an air space between the semen and solution.
4. Attach the glass tip and use the solution to rinse the tip.
5. Perform the inseminations.
6. Do not use the last microlitre of semen. After the inseminations are performed, take up enough saline to suck the petroleum jelly seal from the tip and back into the capillary tube for disposal. Be sure not to get petroleum jelly in the narrow portion of the glass tip as this would then be very difficult to remove.
7. Clean the syringe and glass tip and store in a clean place.

Instead of using a spatula it is possible to use a 1 ml (or 0.5 ml) syringe that is fitted with a short latex, or silicone rubber, nipple to force the petroleum jelly into the end of the tube for sealing.