The development and application of AI in the last four
to five decades especially in cattle have been most striking.
Much research has been stimulated by the rapid expansion
of this practice. Although the storage of semen for 3 to 4
days may be satisfactory for day-to-day requirements of an
AI centre, however, difficulty in maintaining its fertility for
a long time causes a serious wastage of semen form
valuable sires. With the growing realization of the
importance of progeny testing, it became evident that the
development of new methods of semen preservation could
benefit the existing AI semens. In this paper, an overview of
cryopreservation of cattle and buffalo bull semen is
discussed