DETECTION OF ESTROUS-RELATED ODOR IN EWE URINE BY RAMS

The ability of rams to discriminate between urine odour of oestrous ew es and urine odours from ewes at other days of the oestrous cycle was determined using operant conditioning techniques. Rams could discrimin ate between the odour of urine of oestrous ewes and the odours of urin e from ewes at day 6 to day 1 before oestrus and from ewes at day 4 to day 10 after oestrus. Rams did not discriminate between odours of uri ne samples from different ewes in oestrus, or between urine odour of o estrous ewes (day 0) and urine odours from ewes at day 1 to day 3 afte r oestrus. These results support the hypothesis that ewes in oestrus p roduce an odour in wine that is detectable by rams.