In short, yes. But, it’s not as cut and dry and “only in the 24 hours of estrous”. There are secretions before that, and a buck can detect when a doe is ready to breed, or not quite ready. That’s why they (and other ruminants) scent check females and that’s the purpose of the Flehman response. If you were to take urine from a hot doe straight from the bladder, you would get the same response as urine from June.