Influence of ram presence (permanent vs. intermittent) on estrus parameters and behaviours in Kivircik ewes

Abstract

The present study was undertaken to investigate the effects of type of ram presence (permanent vs. intermittent) on estrus onset, estrus duration and frequency of sexual behaviours in Kivircik ewes. During the breeding season, 20 multiparous Kivircik ewes were divided into two groups of permanent (PR) and intermittent (IR) presence of ram. Estrus was synchronized with fluorgestone acetate intravaginal sponges left for 14 days, plus an injection of 600 IU PMSG at the time of sponge removal. PR ewes introduced with ram immediately after sponge removal and remained with the ram throughout the study (5 days). IR ewes were exposed to ram twice a day, only during the observation periods. Behavioural observations were performed twice a day (at 07:00 a. m. and 07:00 p. m.) for a 2-hour period. Estrus onset was 32.40 +/- 1.60 h for PR group and 27.60 +/- 2.40 h for IR group (p > 0.05). Estrus duration was 15.60 +/- 1.83 h and 34.80 +/- 2.15 h for the same groups, respectively (p < 0.001). Standing was the most frequently displayed behaviour in both groups. IR ewes displayed sexual (p < 0.001), eating (p < 0.001), standing (p < 0.001), walking (p < 0.001), urination (p < 0.001) and defecation (p < 0.05) behaviours much more than the PR ewes. Frequency of each sexual behaviour was higher in IR group compared with PR group throughout the study. Among the proceptive behaviours investigated, head-turning was the most frequently displayed behaviour in both groups. Soliciting, non-firm standing, sniffing scrotum and anogenital sniffing behaviours were also expressed by the ewes considerably. It is concluded that, if the ewes are exposed to ram intermittently, behavioural signs of estrus could be recognized more successfully. Furthermore, the possibility of insemination of estrous ewes becomes much higher by the intermittent presence of ram and thus reproductive performance of the herd could be improved.