Intra-uterine insemination of ewes with frozen semen

There have been a number of reports on the frozen storage of ram semen, and artificial insemination with frozen semen has been performed on an experimental basis in several countries. Intensive laboratory studies led to considerable progress regarding the freezing and thawing procedures (Salamon Colas, 1975). However, fertility following insemination tends to be considerably lower than for fresh or chilled semen (Maxwell et al. 1980).