Custom collection and processing of bull semen

Three systems of custom collection and processing of semen are reported. In the first system, semen was collected, evaluated and partially diluted and returned to a central Government laboratory for final dilution and freezing. In the second system the procedure was similar to the first except the semen was returned to the author's laboratory for final dilution and freezing. System 2 reduced the failure to process rate from 20.4% to 6%, but did not significantly improve fertility (64% v's 68% for systems 1 and 2 respectively). A single-stage diluent was used in system 3 and the time from collection to freezing in the author's laboratory was reduced. Both the failure to process rate (0.1%) and the fertility rate of the semen (76%) improved over the other 2 systems.