TY - JOUR
T1 - Prior exposure of maiden ewes to rams enhances their behavioural interactions with rams but it is not a pre-requisite to their endocrine response to the ram effect
AU - Hawken, Penny
AU - Evans, A.C.O.
AU - Beard, A.P.
PY - 2008
Y1 - 2008
N2 - In this study, we tested whether prior experience with rams would modify the behavioural and endocrine responses of maiden ewes to rams. During mid-anoestrus, sexually naive, maiden ewes were exposed to rams for 7 days (ram experienced, RE; n = 61) or isolated from rams (ram naive, RN; n = 63). All ewes were subsequently isolated from rams. In Experiment 1, RE (n = 55) and RN (n = 57) ewes were introduced to rams during late anoestrus. RE ewes had more total and positive interactions with rams than RN ewes (P <0.00 1). RE ewes showed more ram seeking behaviour and spent more time in proximity of rams than RN ewes (at least; P <0.05). In Experiment 2, RE (n = 6) and RN (n = 6) ewes were introduced to rams midway through a frequent blood sampling regime in late anoestrus. Ram introduction stimulated an increase in LH pulse frequency and basal LH in both RE and RN ewes (at least P <0.05). RE ewes had an increase in mean LH concentrations (P <0.01) that failed to reach significance in RN ewes (P <0.1). There was no significant effect of prior experience with rams on LH pulse frequency, amplitude or whether ewes had an LH surge. In conclusion, prior experience with rams is important in developing appropriate ewe-ram interactions but is not a pre-requisite to the endocrine response to the ram effect. (c) 2007 Elsevier B.V. All rights reserved.
AB - In this study, we tested whether prior experience with rams would modify the behavioural and endocrine responses of maiden ewes to rams. During mid-anoestrus, sexually naive, maiden ewes were exposed to rams for 7 days (ram experienced, RE; n = 61) or isolated from rams (ram naive, RN; n = 63). All ewes were subsequently isolated from rams. In Experiment 1, RE (n = 55) and RN (n = 57) ewes were introduced to rams during late anoestrus. RE ewes had more total and positive interactions with rams than RN ewes (P <0.00 1). RE ewes showed more ram seeking behaviour and spent more time in proximity of rams than RN ewes (at least; P <0.05). In Experiment 2, RE (n = 6) and RN (n = 6) ewes were introduced to rams midway through a frequent blood sampling regime in late anoestrus. Ram introduction stimulated an increase in LH pulse frequency and basal LH in both RE and RN ewes (at least P <0.05). RE ewes had an increase in mean LH concentrations (P <0.01) that failed to reach significance in RN ewes (P <0.1). There was no significant effect of prior experience with rams on LH pulse frequency, amplitude or whether ewes had an LH surge. In conclusion, prior experience with rams is important in developing appropriate ewe-ram interactions but is not a pre-requisite to the endocrine response to the ram effect. (c) 2007 Elsevier B.V. All rights reserved.
U2 - 10.1016/j.anireprosci.2007.06.031
DO - 10.1016/j.anireprosci.2007.06.031
M3 - Article
SN - 0378-4320
VL - 108
SP - 13
EP - 21
JO - Animal Reproduction Science
JF - Animal Reproduction Science
ER -