Sexual behaviour of Ile-de-France rams receiving a short term flushing with lupins

This study investigated the effect of a short term (2 weeks) supplementary feeding on sexual behavior traits of Ile-de-France rams during late spring. Ten adult rams were fed a basal diet composed of 0.5 kg of straw, 0.8 kg of hay, 0.27 kg of barley, 0.05 kg of molasses and 0.01 kg of a mineral and vitamins supplement per day providing approximately the neat energy for maintenance according to INRA tables. During two weeks prior to joining, control rams (C) were offered the basal diet, while Supplemented (S) rams received the basal diet and were given 1 kg of lupins per ram per day. The rams were selected based on their sexual motivation and allocated to treatment groups balanced for live weight and testicular volume. Sexual activity of the rams was tested at the end of the supplementary period and following joining with a flock of Ile-de-France ewes. Rams were tested 3 times over a 2-day period. Supplementation did not affect changes in live weight or the testicular volume being 214±57.2 and 215±30 g for C and S rams for the latter trait. Latency to first activity, sniffing investigations, flehmen reaction and lateral approaches were not different between rams of the two groups. Nevertheless, total activity time tended to be longer for supplemented than control rams being 6.8±1.09 and 6.2±0.83 min respectively. Following joining, there was an overall tendency for supplementation to affect negatively sexual behavior traits. Sniffing investigations during the first 30 min of the test were 29.8 and 22 for C and S rams (P<0.05). Average numbers of lateral approaches during the first 180 minutes of the test reached 19 and 11 for C and S rams (P<0.05). Control rams also attempted more mounts without ejaculation than supplemented males. Preliminary conclusions point out to a possible relationship between short-term food supplementation and expression of sexual behavior of male sheep.