Frozen bovine semen
The first such cooperative in America was organized at Clinton, New Jersey, through efforts of Enos J. Perry, Extension Dairyman, New Brunswick, and began operations May 17, 1938.
Osborndale Ivanhoe, who was probably the most famous Holstein bull of the early semen era, died in November 1963.
His grandsons who have dominated the Holstein breed include Carlin-M Ivanhoe Bell, and Round Oak Rag Apple Elevation.
It was placed in containers called glass ampules, sealed, frozen in dry ice and alcohol and kept in that type of solution until it was needed for insemination.
Later the liquid nitrogen refrigerator was invented by Union Carbide with money given to them by John Rockefeller Prentice, who used it exclusively for his bull stud before a number of years later giving it to the entire artificial insemination (A.I.)
Other semen packages that have been tried include the "Magic Wand" developed by Badger Breeders Co-op in the mid-1960s.
Then the straw was placed into a water bath for a period of time to plug the end sealed.
In the late 1960s, a new straw packaging method involving a fully automatic filling and sealing machine was patented by the German vet Ludwig Simmet.
He founded the German company Minitüb, which is since a provider of semen straws and equipment to the industry.
This machine has the capability to print the desired information on each straw, like bull and stud identification, the date of production and even barcodes.
Automatic filling, sealing and printing equipment is today a standard in each bull semen processing lab.
Bull semen can be collected by using an artificial vagina (AV), electro-ejaculator, or by manual massage.
A small screw cap attachment is fitted or drilled preferably in the middle of the housing.
A piece of latex or silicone rubber (usually rough inside, but some cases smooth) then is put through the hose and pulled up at both ends.
Another latex or silicone cone shaped attachment is placed on one end of the AV an held by a rubber band.
On the end of the cone a glass or plastic centrifuge tube is attached usually 15ml size).
A small amount of K-Y jelly or Vaseline is placed just inside on the unconed end and then it is smeared with a pipette or greasing stick.
This will help prevent cold shock to the semen by keeping the cone and tube warm.
After the bull has dismounted, the AV should be held in the upright position so the semen runs into the tube onto the end of the cone.
In some cases where there is not a significant population of females in a particular breed, a bull may have a designated supply of semen collected and then be sent to slaughter.
