Artificial Insemination first began in the 1950's using Frozen bovine semen. This began with artificial insemination companies, that started selling frozen semen. These companies, were known for selling cattle semen from the Holstein breed, known for producing the most amount of milk. In the United States and Canada, these companies sold semen from inbred bulls, known to have 'conquered' the breed and later be the 'Father's' of the major Holstein cows today. The following bulls above, are the most important artificial insemination Holstein bulls of the last century, that have improved the breed worldwide. From 1950's-1960's *Burkgov Inka de Kol *Osborndale Ivanhoe *Rosafe Citation R
From 1960's-1970's *No-Na-Me Fond Matt *Seiling Rockman *Sunnyside Standout-Twin *Pennstate Ivanhoe Star *Pawnee-Farm Arlinda Chief *Roybrook Telstar *Paclamar Astronaut *Paclamar Bootmaker *Round Oak Rag Apple Elevation (Abreviatted RORA Elevation) *Glendell Arlinda Chief *Milu Betty Ivanhoe Chief *Northcroft Admiral Citation *Roybrook Starlite
From 1970's-1980's *Wapa Arlinda Conductor *Marshfield Elevation Tony *Hanoverhill Triple-Threat-Red *Puget-Sound Sheik *Ca-lill Standout Cavalier *Rockalli Son of Bova *S-W-D Valiant *Ocean-View Sexation *Carlin-M Ivanhoe Bell *Leadfield Columbus *Sweet-Haven Tradition *Wagnerscrest Ivanhoe Astronaut *Arlinda Rotate *Cal-Clark Board Chairman *Bridon Astro Jet *Butlerview Mattador *Glenafton Enhancer *Hardys Starwars *Walkway Chief Mark *Hanoverhill Starbuck *Robe-Jan Skylar Chief *Whittier-Farms Ned Boy
From 1980's-1990's *Mel-Est Valiant Iros Melvin *Applenotch Valiant Calypso *Tesk-Holm Valiant Rockie *Exranco Thor *Hanoverhill Inspiration *Utag Valiant Fancy Paul *Exels S-W-D Eagle *Arlinda Melwood *Kinglea Leader *Meadolake Jubilant *Cypress-Hill Laban *Bis-May Tradition Cleitus *Emprise Bell Elton *To-Mar Blackstar *Southwind Bell of Bar-Lee *Townson Lindy *Osdel-Endeavour Bova Cubby *Madawaska Aerostar *Hanoverhill Skybuck *Rothrock Tradition Leadman *To-Mar Wister *Donnandale Skychief *Mark CJ Gilbrook Grand