Storing, shipping and handling embryos

Most semen today can be shipped via Federal Express or U P S in special containers known as “vapor phase” shippers.    These specialized tanks  (MVE calls them “Doble” tanks)  have liners that absorb the liquid nitrogen, and release nitrogen vapor into the center chamber where your semen is placed.    Upon arrival, the correct procedure is to add nitrogen to the center chamber and then transfer the shipment into standard liquid nitrogen semen tanks.

Why add liquid nitrogen into a vapor shipper on arrival?     Liquid Nitrogen is 320F below zero while Nitrogen Vapor is only 140F below zero.     Sperm cells are a simpler cell than an embryo (which has gone through a week of cell division before freezing) and are safe at vapor temps.  However, moving semen canes from vapor temps into the ambient air temp can raise semen temps enough to cause crystalline shifts in the fluids.    This can dislodge essential acrosomal caps on the heads of the sperm cells.    It is the acrosome that enables fertilization of the ovum (merely having “motile” sperm is not enough).

It is for this reason that we suggest your CATTLE VISION semen come through us, as we always have nitrogen at the office to pour into shippers to cool semen down to the liquid temps.    As an added bonus, our volume of orders from C V means you will get “free” shipping, so lowers your total cost.     Maintaining semen quality up to the point of insemination is our goal.

EMBRYOS  ARE  SO  MUCH  TOUCHIER

Optimal storage and transport of embryos is to be in the liquid nitrogen at all times.    While they are often shipped in vapor shippers, here it is essential to have liquid nitrogen to charge that vapor shipper before moving the embryos into your tank storage.

An embryo is eight days old at the time it has been collected and frozen, so have gone through much cell division and is a “layered” cell, 20x the size of a sperm cell.    All those interior walls of membrane are more fragile than the simple tail, body and acrosome cap of a sperm.    Longer storage in vapor (rather than liquid) will cause deterioration of the embryo.

Thus, in our route delivery system, with so many of you storing embryos on the farm, we stick with the eight week recharge interval for your storage tanks, even though the newest models could hold semen safely for twice as long between recharges.     This is designed so that older models and large mouth models, typically only rated for twelve weeks holding, still have that margin of safety that supports long term storage of semen.    BUT if you are storing embryos, your longest holding tanks is where they belong.   In this way, enbryos will always be deep in the liquid volume of the tank not subject to that 180 degree transition from vapor to liquid nitrogen temperature.

WHAT ABOUT THOSE ¼ CC SEXED STRAWS?

These have a minimal of extender and a lower concentration of sperm cells than unsexed straws