Libido testing and the effect of exposing sexually naive Awassi rams to estrous ewes on sexual performance

The study was designed to test libido of Awassi rams and to detect whether their exposure to estrous ewes can improve their sexual performance. Twenty Awassi rams (yearlings and 2-year olds) were subjected to sexual performan ce tests. Yearlings were sexually naive at the beginning of the study. Rams were individually exposed to two estrous Awassi ewes for 30-min periods on five occasions each 2 days apart. Ram sexual behavior was recorded during each 30-min exposure. Yearling rams engaged in more (P<0.01) leg-kicking bo uts and showed higher mounting frequency (P<0.01). Two-year olds managed to raise the fat tail of females more than yearlings (P<0.05) while ejaculati on rate was the same between the two age groups. No ram age x test day inte ractions were detected (P>0.05), however, test day influenced the incidence of mounting (P<0.05) and tail-raising (P<0.01), and ejaculation rate (P<0. 01). Significant correlation (P<0.01) existed between bouts of leg kicking and anogenital sniffing (r=0.4) and between tail raising and ejaculation ra te (r=0.5). These results indicate that exposing sexually naive Awassi rams to estrous ewes before the breeding season may be necessary to improve the ir sexual performance. (C) 1999 Elsevier Science B.V. All rights reserved.