Last night at the Beef Improvement Federation annual meeting in Oklahoma City I got a real education on sexed semen.

It's a technology that's seen major improvements in the last 10 years or so and one I have really intended to research but kept putting on the back burner.

If I understand correctly -- and a web search appears to back this up -- pretty much all commercial semen sexing is being done now by Sexing Technologies, a firm based in Navasota, Texas. In turn, that company contracts with nearly all the major genetics companies to sex-sort semen for them and their customers.

The sorting process is the nifty technology I'll share here. I think it's pretty fascinating how they do it, regardless of whether you'll ever choose sexed semen and/or artificial insemination for your operation or not.

Dustin Dean, director of beef programs for Sexing Technologies, explained how the sorting process works, step by step.

1. They collect semen from up to 50 bulls per day.

2. The semen must pass quality control for semen motility. (Some 22-23% of beef bulls cannot pass this motility test.)

3. The semen is dyed with a red florescent stain, of which the "female" cells soak up a larger amount.

4. A device with a piezo electric crystal shakes 90,000 times per second and creates tiny droplets of seminal fluid with one sperm cell per droplet.

5. As these tiny droplets fall, a grouping of lasers shines through each one and an optical device determines by the color whether it is an X-bearing or a Y-bearing sperm cell.

6. Depending on how the computer has been programmed, the droplet and cell are given an electrical charge, either positive or negative.

7. A magnet pulls the droplet and cell into one stream or another for collection. Sorting can be for female only, male only or both separately. Any droplets/cells that don't quite meet predetermined parameters go into a waste stream and are discarded.

8. A record of what has been sorted off and how it ranks by the preset parameters is displayed on a flat screen by the computer, which tracks all this. It also ranks them for probability of life.

Dean said each collection typically makes 103 straws, which are immediately frozen. The next day the company thaws one and ranks it for purity of sex. Then it thaws another and tests it immediately after thawing for motility. That ranking must be 50% motility to be approved for sale. Then the company thaws a third straw and tests it three hours later for motility. That test must show 30% motility for approval. That leaves 100 saleable straws.

Sexed semen still has slightly lower conception rates than normally frozen semen but only slightly in cows which are truly in estrous. Dean said the rate depends on each individual bull but it will usually be 85% of what that bull's unsexed semen produces.

Also, sexed semen is typically about 90% pure, Dean said, although the company can dictate the purity level within reasonable limits.

Willie Altenburg, associate vice president of beef marketing for Genex, gave this cost example: If a bull's conventional semen sells for $25 per straw then his sexed semen will sell for about $38 per straw.

A simplified movie of the Sexing Technologies sorting process is on the company's website.