Artificial insemination (AI) is the manual collection of semen and placement of semen in the reproductive tract of the female by a method other than natural mating. During the process, the semen has been inspected strictly to assure the quality. AI enables breeding between animals in different geographic locations, or at different time. Moreover, the productivity profit can be increased by using semen from males of high genetic merit for superior females. Because of the increase of breeding efficiency, the cost for raising of male livestock can be decreased by reducing the quantity being raised. (To know more, there are five better ways to improve pig productivity.)

The frequencies of semen collection and preservation methods are different form from species to species. Bulls can produce 10 billion sperms everyday, and they can ejaculate about 5-10 billion sperms each time. Therefore, semen of the bulls under good feeding condition can be collected every other day. For the preservation of bull semen, the canister should be an insulated container with vacuum insulation and filled with liquid nitrogen, which preserves the doses of semen frozen at a temperature of -196℃.

Equine can ejaculate about 5 billion sperms each time and their semen is collected three times a week. Equine semen can be stored at 5℃ and the fertility of the cooled semen remains for approximately 24h. Frozen equine semen is used infrequently. Swine can ejaculate about 100-300 million sperms each time; usually collect their semen is collected twice to five times a week. Swine semen can be stored at 15℃ and the fertility of the cooled semen maintains for 2 days.

Besides the development of semen storage technology, the quality of semen extender is also a key point of artificial insemination. Good semen extender should provide nutrients, protects the sperm cells from cold shock and osmotic shock during the chilling and shipping process, and inhibit bacterial growth. 1ml original semen of a bull can be diluted to 65 folds of its volume. Equine semen can be diluted up to 40 folds, while swine semen can be diluted up to 40 folds.

Before and after dilution, semen concentration and motility should be measured to ensure the sperm is used effectively. In addition to using well-established tools, such as CASA (Computer-assisted sperm analysis) systems or photometer to analyze sperm quality, iSperm analyzer (Aidmics Biotechnology) can analyze sperm's morphology, concentration and motility right on iPad mini. iSperm is user-friendly and minimum training is required. With iSperm, breeders can now check semen quality along the way of artificial insemination whenever they are in need.

Reference

1. Foote, R. H. and G. W. 1968.Trimberger.Artificial insemination. ln:Reproductionin FarmAnimals.
2. Standard Operating Procedures for Bull Management. http://ppt.cc/uFZt6
3. Artificial Insemination in Farm Animals.2011. http://www.intechopen.com/books/artificial-insemination-in-farm-animals