Sexually mature ewes cycle through heat every seventeen days, on average. In reality, that means that any one ewe’s cycle can last anywhere from two to three weeks in length. Without a ram, there is no way to know when a ewe comes into heat; unlike with other mammals, there is no external sign that the ewe is receptive and fertile.
Sheep recognize breeding very much by scent. I’ve been told that a ram can smell a ewe in heat from about a mile away. We’ve never tested this, but I know from experience that they can certainly tell when there is a ewe cycling on the other end of our acreage – and that is a quarter mile – so I don’t doubt that they have a good sense of smell for this specific purpose.
But it isn’t only the ewes who produce the scent of pheromones to induce breeding. Beginning at about this time of years, rams begin to produce a strong “rammy” smell that follows them as they pass by. When we handle the rams to change coats or for health reasons, others can always tell that we have done so, since we walk away with that same rammy scent that pervades the senses and just doesn’t seem to leave us until we scrub it off in the shower!
Ewes are attracted to this scent and it makes them more receptive for breeding. In fact, it is not uncommon for ewes who are not yet cycling to begin to do so simply because a ram has been placed nearby to introduce his scent to the ewes. The smell is seasonal, and strongest just before and during fall breeding – the reason we shear our rams after spring rains have had a chance to wash the scent out of the wool. Adult rams generally have a stronger odor than the ram lambs, which can make things difficult for a lamb trying to work in a group. It isn’t uncommon for the ewes to prefer the smelliest ram – and because the ram lamb’s scent is not nearly so strong yet, the cycling ewe in his group will often walk the fenceline that separates her from the adult rams.
Ram lambs actually have a dual problem: not only do the adult rams in neighboring fields overpower the ram lamb with their scent, attracting his ewes, but he also has no experience doing what it is he needs to do. The drive to procreate is strong, but it often takes him a while to figure out where the attracting scent is coming from and what it is that he is driven to do about it. If the ram lamb’s group is in a large field, it can be especially difficult for him to figure things out.
In our own groups this fall, we will be running one ram lamb in our Romney groups (our Romeldale groups will all be led by adult rams), and I’ve been working on ways to manage things to try to aim for success. The ram lamb in question, named Quest, was a large newborn at over seventeen pounds, and has continued with impressive growth to date. He has lustrous, crimpy, long-stapled fleece on a structurally sound body. We measured his scrotum weeks ago and he was definitely within the realm of a young working ram, so he will get a chance to show us what he can do. In order to help smooth his introduction, I’ve decided to cut our smallest field (the East Pasture) in half even though he will have one of our larger groups. In only half of the East Pasture, his somewhat diminished scent (due to his young age and developing levels of testosterone) should overpower the much more distant scents of the other working rams wafting in from other fields. It will also put him within a very short distance of each and every one of his ewes, so he should easily recognize the scent of any ewe who may be in heat. It is about all I can do – the rest is up to him!
This year, our breeding season begins on Saturday, September 16th, and will run for 6-7 weeks until around November 1 – the exact length will depend upon Quest. If we find that he is marking his ewes very early on, then he can have them for the four early weeks, and then we will shift them in with the working adult rams for the final three weeks of the overall seven. If, however, Quest seems lost among the ewes, wandering about and crying for his male flock-mates or eating without checking his ewes, then after an attempt of two or three weeks, we will break down his group and put his ewes in among the other three Romney groups. If we move them fairly early, we will run our groups for just six weeks total, since the adult rams will need only a single cycle at that point to cover the additions to their groups.
Each ewe has been placed into the group that I believe will have the best chance of producing the best combination of traits in the resulting lambs – but only time will tell if I have chosen correctly. This is an exciting time for the shepherd as we look forward and anticipate the lambs to come and the progress our flock may make because of them. It is an exciting time for the rams as they begin to scent the ewes, now always grazed nearly 1/4 mile away to make illicit breeding less possible. The rams stand at the nearest fenceline with noses to the breeze and upper lip curled in the Flehmen response to expose the vomeronasal organ that picks up that heady scent of a ewe in heat. They know that this is the season – they can smell it! And the ewes, too, know the time is near – the scent of the rams is strong and getting stronger by the day. I watch the calendar and know that we all have only two weeks left to wait!