Semen

[inyati13]

Semen is a complex fluid containing much more than spermatozoa. Besides the gonads, other glands discharge into the fluid that ultimately becomes semen. Such as, enzymes, lubricants, buffering compounds and food (for example fructose) to promote the survival of spermatozoa and provide a medium through which they move.
My question is this: Is the content of a semen straw, the same as the content of the bull's natural semen or do they concentrate it providing more spermatozoa per unit of volume? The purpose of the question, I am wondering that since AI is done on the uterine side of the cervix versus the vaginal side as a bull would do in nature, is there a lessor need for the constituents in the semen that promote mobility, provide nutrients and buffering compounds, and ensure the viability of the spermatozoa when and if they reach the oocyte.

 

[dun]

It has stuff added to dilute it, usually antibiotics and some form of food/nutrition. Not sure what else may be in there

 

[Fire Sweep Ranch]

It's been years, but if I remember correctly, semen extender has different properties to it depending on the manufacturer. Some straws of semen are white, some yellow. That is because of the base of the extender - egg yolk or milk. Genex uses milk, if I remember correctly. The purpose of the extender is to take the ejaculate and extend it so you can get more pregnancies from it. So in the extender is a food source for the semen when it is thawed, along with an antibiotic. I think there is also a content that helps the covering over the sperm head break down so that when it reaches the oocyte, after the zona pellucida is worn down, it can penetrate the oocyte. Along with a preservative to help the spermatozoa survive the freezing process. YEARS ago I worked at ARS, a reproductive company that makes semen extenders and "blue box" that measures an ejaculate (http://www.arssales.com/b-590b.html). I also had to come up with the formulation to mass produce rooster semen extender, but it was all chemical analysis stuff. I did learn how to ejaculate a rooster from that experience.... probably something I will never use again!

 

[cow pollinater]

I'll add to what's already been said that the quarter cc straws have less extender than the half cc straws but the same amount of viable sperm.
Also, the amount of semen that needs to be in each straw has been a known variable for quite a while now. I don't remember the exact numbers but we know that there has to be at least X number of sperm cells in a straw to consistantly impregnate cows and in order to improve conception we would have to add X more.

 

[inyati13]

Thanks dun, you are always there. Hope I meet you some day. Fire Sweep, you are on your game, gal.