Fertility following deposition of equal numbers of frozen-thawed ram spermatozoa by single and double insemination

Abstract

Fertility results are presented for 90, 180 and 360 x lo6 total frozen-thawed motile spermatozoa deposited by single or double insemination. There was no difference between the mean lambing results for single (44.4%, 59/133) and double insemination (46.2%, 61/132). Number of inseminations within the sperm dose had no effect on fertility. Increasing the number of motile spermatozoa improved the fertility, the mean lambing rates for 90, 180 and 360 x l06 spermatozoa being 32.5% (29/89), 47.7% (42/88) and 55.7% (49/88) respectively.