Effects of change of the stimulus ewe on sexual performance of crossbred rams

The purpose of this study was to investigate the effect of changing stimulus ewe on sexual performance of Arkharmerino×Moghani rams. Males were submitted to two different sexual stimulation procedures. At first procedure، the same ewe was used as the female stimulus for two consecutive presentations، but at second procedures the stimulus ewe was replaced after the first presentation by a new ewe. Sexual behaviors were recorded by observers outside the pen. The only significant difference showed between two sexual procedures about latency for first mount (91. 78 vs. 44. 15 second respectively for first and second sexual procedures، P<0. 05). However، the differences between any of the groups in terms of anogenital investigations without Flehmen، anogenital investigations with Flehmen، mount attempt، Foreleg kicks، latency for first ejaculation، time from the first ejaculation until next mount and mount without ejaculation were statistically insignificant. The results showed that under cold region، crossbred rams exhibit full repertoire of sexual behaviors، Hence، the changing of stimulus ewe could not be a positive influence on sexual performance of rams.