The preservation of semen for several days is possible by spinning it immediately after collection and adding an chilled semen extender and gradually cooling it to 4 degrees centrigrade. Depending on the quality of the semen, the extender and the cooling curve it is possible to keep up the motility till 10 days. The capability of fertilizing ova is most of the time much less. Up to 5 days maximum is more realistic.
We use different extenders depending on the needed time to cover and the specific semen factors. The extenders are : Canirep, Mofa and Minitube.
Right after the collection we do a quality assessment before and after extending. We can send this digitally to the owner of the male and the receiving party before sending the semen. Also it is possible to email the moving images and the morphology images. In that way an objective documentation is warranted.
Chilled semen is very easy to use in case of a short period of stocking the semen or for distribution within Europe and to other countries where no quarantine regulations make it impossible to do so. The USA and Canada are countries where we can send chilled canine semen to with good results.
For the actual transportation at 4 degrees Centrigrade we use a disposable box that can hold the semen cooled for 2 days. For most destinations this is enough to send the semen without loss of quality. A photo of the box you can see here. After arriving at the destination the semen can be stored in the refrigerator if more time is needed for the female to reach the optimum timeperiod.
The costs of using chilled semen in total (collection, extending, packaging, transportation) are less then using frozen semen. The price of freezing is higher then chilling and the transportation of frozen semen is more costly because of the need of using special containers with liquid nitrogen (dryshippers).
Another advantage of using chilled semen is the use of the total collection for shipping and insemination while in case of frozen semen a collection most of the time is divided into several breeding-units. This is the minimal amount of semen needed for fertilization (100-150 million sperms with good motility and morphology).
For optimal results the best way to organise matings with chilled semen is that there is a maximum timeframe between the collection and the insemination of 36 hours. The shorter the better. In general the results of inseminations with chilled semen can be just as good as a natural mating if the semen after collection is of good quality, the timing is good and the insemination is done by TCI. Hereby the semen is deposited directly in the uterus by means of an endoscopically guided flexible catheter.