Semen extender is a product that can be mixed with semen to prevent it from deteriorating while it is being held or shipped for eventual insemination. Various types of semen extender are often used by animal breeders who may need to ship semen to other breeders across the country or even around the world. Semen extender is sometimes also used for preserving human semen. An extender works by preventing bacterial contamination, offering nutrition to the sperm and protecting the sperm against various types of shocks that can take place during the storage and shipping process. The ingredients in semen extender vary, but many include dairy products and egg yolks depending on how the semen is to be prepared or stored for shipping.
Many companies produce different types of semen extender, each best suited to a different type of sperm or a different method of storage. Breeders, or those involved with artificial insemination will need to choose the semen extender that is best suited to their needs. If a breeder, medical professional, or someone who is participating in artificial insemination plans to hold semen in a cold environment for a day or two, he or she may decide to use an extender that includes milk products. On the other hand, if the semen is to be frozen, egg yolk may be the nutrient of choice. In addition to commercial semen extenders, it is possible for breeders to mix their own product.
The importance of semen extender is significant because many livestock and domestic pet breeders rely on semen obtained from animals that they themselves do not own. Transporting an animal for breeding purposes is often time-consuming and expensive, and in the case of livestock, it is often much more efficient to use artificial insemination in order to increase one's herd. Breeders use various methods to collect sperm from their animals and may then deliver or mail the semen to other breeders or ranchers who can then use it in the insemination of their female animals. Domestic animal breeders will often do likewise, as in the world of competitive cat and dog breeding, in which careful breeding is both an art and a science. Human sperm donors may also make use of semen extender when sending their sperm by mail to women who live far away; In fact, there are commercially available “do it yourself” home insemination kits that include specially formulated semen extenders for human use.