Quote Originally Posted by TFX View Post
Nobody has ever centrifuged semen I have collected.

You really can't do it yourself. First of all, every extender "recipe" works differently with different animals. Ideally, you need to waste a collection testing extenders before you know which extender to use with each particular dog. The semen is frozen, thawed, and the several extender samples tested to see which extender has the best counts. Now you are set to freeze the next collections from the dog knowing which extender to use for guaranteed results.

Sperm count and motility will diminish in your proposed scenario, as Nash pointed out.
I have a lab and we collect from several dogs on a regular basis. Using the centrifuge before storing it is a must for many reasons. The main reason is seminal plasma (the material you spin off with the centrifuge separating it from the sperm) is "toxic" to sperm. Second reason is, im storing semen, not seminal plasma... no use for that. Lastly by centrifuging it and adding the correct ratio of extender you have an accurate count on the concentration of sperm in the straw. I dont think ive seen a freezing method that didnt require the collection to be centrifuged before freezing. Although im not licensed in this field, through research, trial, and error... the results achieved are sufficient for our needs.